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Assembling a safe and effective toolbox for integrated flea control and plague mitigation: Fipronil experiments with prairie dogs

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Free PMC article

Abstract

Background: Plague, a widely distributed zoonotic disease of mammalian hosts and flea vectors, poses a significant risk to ecosystems throughout much of Earth. Conservation biologists use insecticides for flea control and plague mitigation. Here, we evaluate the use of an insecticide grain bait, laced with 0.005% fipronil (FIP) by weight, with black-tailed prairie dogs (BTPDs, Cynomys ludovicianus). We consider safety measures, flea control, BTPD body condition, BTPD survival, efficacy of plague mitigation, and the speed of FIP grain application vs. infusing BTPD burrows with insecticide dusts. We also explore conservation implications for endangered black-footed ferrets (Mustela nigripes), which are specialized predators of Cynomys.

Principal findings: During 5- and 10-day laboratory trials in Colorado, USA, 2016-2017, FIP grain had no detectable acute toxic effect on 20 BTPDs that readily consumed the grain. During field experiments in South Dakota, USA, 2016-2020, FIP grain suppressed fleas on BTPDs for at least 12 months and up to 24 months in many cases; short-term flea control on a few sites was poor for unknown reasons. In an area of South Dakota where plague circulation appeared low or absent, FIP grain had no detectable effect, positive or negative, on BTPD survival. Experimental results suggest FIP grain may have improved BTPD body condition (mass:foot) and reproduction (juveniles:adults). During a 2019 plague epizootic in Colorado, BTPDs on 238 ha habitat were protected by FIP grain, whereas BTPDs were nearly eliminated on non-treated habitat. Applications of FIP grain were 2-4 times faster than dusting BTPD burrows.

Significance: Deltamethrin dust is the most commonly used insecticide for plague mitigation on Cynomys colonies. Fleas on BTPD colonies exhibit the ability to evolve resistance to deltamethrin after repeated annual treatments. Thus, more tools are needed. Accumulating data show orally-delivered FIP is safe and usually effective for flea control with BTPDs, though potential acute toxic effects cannot be ruled out. With continued study and refinement, FIP might be used in rotation with, or even replace deltamethrin, and serve an important role in Cynomys and black-footed ferret conservation. More broadly, our stepwise approach to research on FIP may function as a template or guide for evaluations of insecticides in the context of wildlife conservation.

Conflict of interest statement

The authors have declared that no competing interests exist.

Reevaluation of the Role of Blocked Oropsylla hirsuta Prairie Dog Fleas (Siphonaptera: Ceratophyllidae) in Yersinia pestis (Enterobacterales: Enterobacteriaceae) Transmission.

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Miarinjara A(1)(2), Eads DA(3), Bland DM(1), Matchett MR(4), Biggins DE(3), Hinnebusch BJ(1). Author information: (1)Laboratory of Bacteriology, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, NIH, Hamilton, MT, USA. (2)Department of Environmental Sciences, Emory University, Atlanta, GA, USA. (3)U.S. Geological Survey, Fort Collins Science Center, Fort Collins, CO, USA. (4)U.S. Fish and Wildlife Service, Lewistown, MT, USA. Prairie dogs in the western United States experience periodic epizootics of plague, caused by the flea-borne bacterial pathogen Yersinia pestis. An early study indicated that Oropsylla hirsuta (Baker), often the most abundant prairie dog flea vector of plague, seldom transmits Y. pestis by the classic blocked flea mechanism. More recently, an alternative early-phase mode of transmission has been proposed as the driving force behind prairie dog epizootics. In this study, using the same flea infection protocol used previously to evaluate early-phase transmission, we assessed the vector competence of O. hirsuta for both modes of transmission. Proventricular blockage was evident during the first two weeks after infection and transmission during this time was at least as efficient as early-phase transmission 2 d after infection. Thus, both modes of transmission likely contribute to plague epizootics in prairie dogs. Published by Oxford University Press on behalf of Entomological Society of America 2022. DOI: 10.1093/jme/tjac021 PMID: 35380675

A novel mechanism of streptomycin resistance in Yersinia pestis: Mutation in the rpsL gene

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Abstract

Streptomycin is considered to be one of the effective antibiotics for the treatment of plague. In order to investigate the streptomycin resistance of Y. pestis in China, we evaluated strep- tomycin susceptibility of 536 Y. pestis strains in China in vitro using the minimal inhibitory concentration (MIC) and screened streptomycin resistance-associated genes (strA and strB) by PCR method. A clinical Y. pestis isolate (S19960127) exhibited high-level resis- tance to streptomycin (the MIC was 4,096 mg/L). The strain (biovar antiqua) was isolated from a pneumonic plague outbreak in 1996 in Tibet Autonomous Region, China, belonging to the Marmota himalayana Qinghai–Tibet Plateau plague focus. In contrast to previously reported streptomycin resistance mediated by conjugative plasmids, the genome sequenc- ing and allelic replacement experiments demonstrated that an rpsL gene (ribosomal protein S12) mutation with substitution of amino-acid 43 (K43R) was responsible for the high-level resistance to streptomycin in strain S19960127, which is consistent with the mutation reported in some streptomycin-resistant Mycobacterium tuberculosis strains. Streptomycin is used as the first-line treatment against plague in many countries. The emergence of strep- tomycin resistance in Y. pestis represents a critical public health problem. So streptomycin susceptibility monitoring of Y. pestis isolates should not only include plasmid-mediated resistance but also include the ribosomal protein S12 gene (rpsL) mutation, especially when treatment failure is suspected due to antibiotic resistance.

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Two fatal cases of plague after consumption of raw marmot organs

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Emerg Microbes Infect. 2020; 9(1): 1878–1880.
Published online 2020 Aug 21. doi: 10.1080/22221751.2020.1807412
PMCID: PMC7473306
PMID: 32762515
Jan Kehrmann,a Walter Popp,b,c Battumur Delgermaa,d Damdin Otgonbayar,d Tsagaan Gantumur,e Jan Buer,a and Nyamdorj Tsogbadrakhd

ABSTRACT

Marmots are an important reservoir of Yersinia pestis and a source of human plague in Mongolia. We present two fatal cases of plague after consumption of raw marmot organs and discuss the distribution of natural foci of Y. pestis in Mongolia.

Letter

Plague, caused by Yersinia pestis, is one of the most dreaded diseases in the world and has killed millions of people over the centuries [1]. Y. pestis has acquired virulence factors that make it a unique member of the family of Yersiniaceae, transmitted as a predominantly vector-borne pathogen. Plague is an endemic disease in many parts of the world. Wild rodents are an important reservoir of Y. pestis and its maintenance relies on flea vectors and climate [2]. Climate conditions affect all three components of the plague cycle: bacteria, vectors and animal hosts. Marmots are the main reservoir of Y. pestis in Mongolia and are an important source of human infection [3,4]. Y. pestis is commonly transmitted by fleabites. However, plague after the consumption of raw meat has rarely been reported [5-7]. Here, we present two fatal cases of plague caused by eating raw marmot organs, and we discuss the epidemiology of Y. pestis infection of small rodents in Mongolia.

A 38-year old Mongolian resident of Kazakh ethnicity from Bayan Ulgii aimag (province) in western Mongolia worked as a border guard. He called the emergency medical service from his home, reporting fever, abdominal pain, and bloody vomitus. Soon after his call, he died (28 April 2019). He had hunted and prepared marmots on 22 and 25 April and had been vaccinated with an EV76 Y. pestis vaccine one year previously. He and his 37-year old wife had consumed meat and raw marmot organs (kidney, stomach and gallbladder) on 22, 23, and 25 April. His wife visited a physician daily from 26 to 28 April because of fever, diarrhoea, abdominal pain, vomiting, and headache. She reported celebrating with friends between 22 and 25 April but concealed her contact with and consumption of raw marmot meat. Retrospective interviews with neighbours and older children revealed that the man and his wife were the only persons in the group of friends who had consumed raw marmot meat. The wife refused in-hospital diagnostic tests and was treated as outpatient with erythromycin and anti-inflammatory drugs. After the husband died at home, a tentative diagnosis of plague was made for the wife, and she was treated in the hospital with intravenous gentamicin and ceftriaxone. However, she died on 1 May. The couple left behind four children aged between nine months and twelve years.

Autopsy of the husband on 29 April found no fleabites or enlarged lymph nodes. His inner organs (stomach, oesophagus, liver, kidneys, and lungs) were enlarged and blood-filled and showed signs of inflammation. Y. pestis was cultured on Hottinger blood agar and detected by PCR with Pla1 (5’GAATGAAAATCTCTGAGG3’) and Pla2 (5’TCCAGCGTTAATTACGG3’) and pFRA1 (5’TCAGTTCCGTTATCGCC3’) and pFRA2 (5’GTTAGATACGGTTACGGT3’) primers from blood, liver, spleen, lung, kidney, stomach, brain and bone marrow. The identification was confirmed by phage lysis according to the Mongolian national guidelines. The wife presented with pharyngeal inflammation and swollen cervical lymph nodes. Y. pestis was detected by PCR and by culture of samples from an enlarged cervical lymph node. Y. pestis was also detected in swab specimens from the inflamed throat, blood, and gut.

Although both cases involved zoonotic and not interhuman infections, the detection of Y. pestis in the lungs during autopsy prompted the authorities to follow infection prevalence measures. Because it was possible that both patients had contracted secondary pneumonic plague, the authorities followed the Mongolian national plague guidelines for pneumonic plague. All 124 persons who had come into close contact with the couple between 22 and 28 April were treated prophylactically with doxycycline or ciprofloxacin. Ulgii city (34,000 residents) was quarantined from 1 to 6 May. F1-antigen tests were performed on throat swab specimens of 198 close contact persons, family members, friends, colleagues, and medical staff at least six days after the last contact, and all results were negative.

Annual surveys of the prevalence of Y. pestis in Mongolia from 2012 to 2019 found that 137 soums (districts) of 13 aimags have natural plague foci, with a high infection prevalence for Bayan Ulgii in the western part of the country (Figure 1(A)). The infection prevalence of marmots and their associated fleas in Bayan Ulgii aimag was 20.2% in 2018 and 16.8% in 2019. It was determined from testing 287 small rodents and 261 fleas in 2018 and 397 small rodents and 312 fleas in 2019 in this area by serologic tests and PCR: in case of positivity, bacteriologic culture was performed additionally.

A. Geographic distribution of natural foci of plague in Mongolia as assessed from 2012 to 2019. Categorization of prevalence took into account the extent and continuity of Y. pestis infection of small rodents in various regions of Mongolia over the past eight years. For each aimag (province), a minimum of 80–100 small rodents and fleas associated with the rodents in an area 100–120 kilometres square were examined annually with serologic tests (F1-antigen and plague specific antibody test) and polymerase chain reaction (PCR). Positive samples were subjected to bacteriologic culture. B. Picture of Marmota sibirica. C and D. Preparation of traditional marmot boodog: Burning furs with flame (C) and cooked marmot boodog (D).

Of the 73 reported cases of plague in Mongolia since 1998, 59% have been associated with close contact with infected marmots and 7% with eating raw marmot organs (data provided by National Centre for Zoonotic Diseases, Ministry of Health, Ulaanbaatar, Mongolia).

The rapid clinical course of the disease and the absence of signs of lymphadenitis with the detection of Y. pestis in the blood indicate that the husband died of septicaemic plague caused by the consumption of raw marmot infected with Y. pestis. Y. pestis infection occurred even though the man had received an EV76 vaccine one year previously. There is no evidence showing that the available Y. pestis vaccines provide humans with long-lasting immunity and protection from plague [8,9].

The combination of pharyngeal inflammation, swollen cervical lymph nodes, detection of the pathogen in cervical lymph node tissue and pharyngeal swab specimens, and the absence of fleabites indicate that the wife was also infected by consuming raw marmot meat. Pharyngeal inflammation and swollen cervical lymph nodes have previously been reported among patients who have consumed raw marmot meat [5,6,10]. The wifés concealment of consumption of raw marmot meat contributed to a delayed diagnosis. Because hunting marmots has been prohibited by the Mongolian government since 2014, Mongolians fear punishment when they admit this activity. Marmot, prepared as boodog (filled with hot stones), is a national dish in Mongolia (Figure 1(B–D)), and, because Mongolians assume that boodog has healthful benefits, marmot hunting is a covert activity. When marmots are prepared for boodog, especially before the fur is burnt away with a blowtorch, fleas infected with Y. pestis may change their host, thereby typically causing bubonic plague. Marmota sibirica, a species that also lives in Western Mongolia, exhibits a relatively high resistance to plague (50%–80% survive infection), a feature that has been suggested to play an important role in the persistence of the pathogen [3].

The habit of eating infected raw marmot meat is a possible means of infection with plague in Mongolia. Cooking efficiently inactivates Y. pestis [11]: thus, infections in Mongolia are associated with consumption of raw meat, not with the consumption of cooked boodog. The most important mode of Y. pestis infection in Mongolia is close contact with infected marmots. A study from Zambia [12] found that the risk of transfer of Y. pestis from infected fleas on captured animals to humans is higher during hunting and transporting of marmots rather than during preparation of animals for food. That study showed that hunting behaviour, mode of transportation of carcasses, and method of preparation of carcasses may substantially influence the risk of flea transmission.

A diagnosis of plague should be considered in areas with active plague foci, including the Bayan Ulgii aimag in the western part of Mongolia [3,13] where the dead couple resided. Only few reports of plague connected with the consumption of raw meat have been published to date; most cases are associated with the consumption of raw or undercooked camel meat [5–7,10]. The patients reported here had no fleabites and their predominant symptoms were bloody vomitus and sepsis in one case and gastrointestinal symptoms and pharyngeal inflammation in the other. Therefore, we conclude that the infections were caused by the consumption of raw marmot meat.

Marmot meat is considered a delicacy in Mongolia, but its consumption confers a risk of Y. pestis infection. In plague-endemic districts, healthcare professionals obtaining a patient´s medical history should ask about consumption of marmot and plague should be considered as a tentative diagnosis. Communicating the risk of Y. pestis infection after close contact with or consumption of marmot meat, especially raw meat, may increase the awareness of plague among the population.

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References

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Emerg Microbes Infect. 2020; 9(1): 1878–1880.
Published online 2020 Aug 21. doi: 10.1080/22221751.2020.1807412
PMCID: PMC7473306
PMID: 32762515
Jan Kehrmann,a Walter Popp,b,c Battumur Delgermaa,d Damdin Otgonbayar,d Tsagaan Gantumur,e Jan Buer,a and Nyamdorj Tsogbadrakhd


FLEA PARASITISM AND HOST SURVIVAL IN A PLAGUE-RELEVANT SYSTEM: THEORETICAL AND CONSERVATION IMPLICATIONS.

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Author information:
1. US Geological Survey, Fort Collins Science Center, 2150 Centre Avenue, Building C, Fort Collins, CO 80526, USA’.
2. US Geological Survey, National Wildlife Health Center, 6006 Schroeder Road, Madison, WI 53711, USA

Abstract

Plague is a bacterial zoonosis of mammalian hosts and flea vectors. The disease is capable of ravaging rodent populations and transforming ecosystems. Because plague mortality is likely to be predicted by flea parasitism, it is critical to understand vector dynamics. It has been hypothesized that paltry precipitation and reduced vegetative production predispose herbivorous rodents to malnourishment and flea parasitism, and flea parasitism varies directly with plague mortality. We evaluated these hypotheses on five colonies of Utah prairie dogs (UPDs; Cynomys parvidens), on the Awapa Plateau, Utah, USA, in 2013-16. Ten flea species were identified among 3,257 fleas from UPDs. These 10 flea species parasitize prairie dogs, mice, rats, voles, ground squirrels, chipmunks, and marmots, all known hosts of plague. The abundance of fleas on individual UPDs (1,198 observations) varied inversely with UPD body condition; fleas were most abundant on lightweight, malnourished UPDs. Flea abundance on UPDs was highest in dry years that were preceded by wet years. Increased precipitation and soil moisture in the prior year might generate humid microclimates in UPD burrows (that could facilitate flea survival and reproduction) and paltry precipitation in the current year could predispose UPDs to malnourishment and flea parasitism. Annual re-encounter rates for UPDs (1,072 observations) were reduced in wetter years preceded by drier years; reduced precipitation and vegetative production might kill UPDs, and increased flea densities in drier years could provide conditions for plague transmission (and UPD mortality) when moisture returns. Re-encounter rates were reduced for UPDs carrying at least one flea compared to UPDs with no detected fleas. These results support the hypothesis that reduced precipitation in the current year predisposes UPDs to flea parasitism. Our results also suggest a link between flea parasitism and UPD mortality. Given documented connections between flea parasitism and plague transmission, our results point toward an effect of flea parasitism on plague-related deaths for individual UPDs, a phenomenon rarely investigated in nature.

 

PMID: 31880988

Plague-Positive Mouse Fleas on Mice Before Plague Induced Die-Offs in Black-Tailed and White-Tailed Prairie Dogs.

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Bron GM 1, 2, Malavé CM 1, Boulerice JT 3, Osorio JE 2, Rocke TE 1.

Author information:
1. 1 U.S. Geological Survey National Wildlife Health Center, Madison, Wisconsin.
2. 2 Department of Pathobiological Sciences, University of Wisconsin-Madison, School of Veterinary Medicine, Madison, Wisconsin.
3. 3 Wyoming Game and Fish Department, Laramie, Wyoming.

Abstract

Plague is a lethal zoonotic disease associated with rodents worldwide. In the western United States, plague outbreaks can decimate prairie dog (Cynomys spp.) colonies. However, it is unclear where the causative agent, Yersinia pestis, of this flea-borne disease is maintained between outbreaks, and what triggers plague-induced prairie dog die-offs. Less susceptible rodent hosts, such as mice, could serve to maintain the bacterium, transport infectious fleas across a colony, or introduce the pathogen to other colonies, possibly facilitating an outbreak. Here, we assess the potential role of two short-lived rodent species, North American deer mice (Peromyscus maniculatus) and Northern grasshopper mice (Onychomys leucogaster) in plague dynamics on prairie dog colonies. We live-trapped short-lived rodents and collected their fleas on black-tailed (Cynomys ludovicianus, Montana and South Dakota), white-tailed (Cynomys leucurus, Utah and Wyoming), and Utah prairie dog colonies (Cynomys parvidens, Utah) annually, from 2013 to 2016. Plague outbreaks occurred on colonies of all three species. In all study areas, deer mouse abundance was high the year before plague-induced prairie dog die-offs, but mouse abundance per colony was not predictive of plague die-offs in prairie dogs. We did not detect Y. pestis DNA in mouse fleas during prairie dog die-offs, but in three cases we found it beforehand. On one white-tailed prairie dog colony, we detected Y. pestis positive fleas on one grasshopper mouse and several prairie dogs live-trapped 10 days later, months before visible declines and plague-confirmed mortality of prairie dogs. On one black-tailed prairie dog colony, we detected Y. pestis positive fleas on two deer mice 3 months before evidence of plague was detected in prairie dogs or their fleas and also well before a plague-induced die-off. These observations of plague positive fleas on mice could represent early spillover events of Y. pestis from prairie dogs or an unknown reservoir, or possible movement of infectious fleas by mice.

Prairie Dogs, Persistent Plague, Flocking Fleas, and Pernicious Positive Feedback.

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1. Front Vet Sci. 2019 Mar 28;6:75. doi: 10.3389/fvets.2019.00075. eCollection 2019.
Biggins DE 1, Eads DA 1, 2.

Author information:
1. United States Geological Survey, Fort Collins Science Center, Fort Collins, CO, United States.
2. Department of Biology, Colorado State University, Fort Collins, CO, United States.

Abstract

Plague (caused by the bacterium Yersinia pestis) is a deadly flea-borne disease that remains a threat to public health nearly worldwide and is particularly disruptive ecologically where it has been introduced. We review hypotheses regarding maintenance and transmission of Y. pestis, emphasizing recent data from North America supporting maintenance by persistent transmission that results in sustained non-epizootic (but variable) rates of mortality in hosts. This maintenance mechanism may facilitate periodic epizootic eruptions “in place” because the need for repeated reinvasion from disjunct sources is eliminated. Resulting explosive outbreaks that spread rapidly in time and space are likely enhanced by synergistic positive feedback (PFB) cycles involving flea vectors, hosts, and the plague bacterium itself. Although PFB has been implied in plague literature for at least 50 years, we propose this mechanism, particularly with regard to flea responses, as central to epizootic plague rather than a phenomenon worthy of just peripheral mention. We also present new data on increases in flea:host ratios resulting from recreational shooting and poisoning as possible triggers for the transition from enzootic maintenance to PFB cycles and epizootic explosions. Although plague outbreaks have received much historic attention, PFB cycles that result in decimation of host populations lead to speculation that epizootic eruptions might not be part of the adaptive evolutionary strategy of Y. pestis but might instead be a tolerated intermittent cost of its modus operandi. We also speculate that there may be mammal communities where epizootics, as we define them, are rare or absent. Absence of plague epizootics might translate into reduced public health risk but does not necessarily equate to inconsequential ecologic impact.

PMCID: PMC6447679 Free PMC Article

Effects of Deltamethrin Treatment on Small Mammal and Ectoparasite Population Dynamics and Plague Prevalence in a North American Mixed-Grass Prairie System.

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Maestas LP1, Britten HB1.

Author information

Department of Biology, University of South Dakota, Vermillion, South Dakota.

Abstract

Sylvatic plague affects many species in North American prairie ecosystems. Deltamethrin is commonly used to manage fleas in potential outbreak areas. Understanding the role of small mammals and their ectoparasites in sylvatic plague maintenance is pertinent to understanding the ecology of plague and its persistence in nature. This study examined the effects of plague management using deltamethrin on communities of small mammals, their flea faunas, and Yersinia pestis prevalence. We trapped small mammals from 2014 to 2016 on the Lower Brule Indian Reservation (LOBR), South Dakota, and analyzed the effects of deltamethrin treatment on small mammal populations, flea loads, and Y. pestis prevalence. We collected higher flea loads from small mammals on sites not treated with deltamethrin (1.10 fleas per animal) than from deltamethrin-treated sites (1.03 fleas per animal). We observed significant negative trends in mean flea load per animal between pre- and post-treatment collections. We detected no significant effects of deltamethrin treatment on animal captures pre- and post-treatment, but observed significant differences in animal captures by experimental unit. We detected no serological evidence for the presence of Y. pestis antibodies in small mammals and 1.2% Y. pestis prevalence across all sampled fleas. Although there is little overlap in the species of fleas infesting small mammals and prairie dogs, the occurrence of flea spillover has been documented. In our study, treatment with deltamethrin reduced flea loads on small mammals by up to 49%. Our data suggest that although the efficacy of deltamethrin on the LOBR-a mixed-grass system-may not be as high as that found in a comparable study in a short-grass system, deltamethrin is still a useful tool in the management of plague.

KEYWORDS:

; South Dakota; deltamethrin; fleas; plague management; small mammals

Third cat tests positive for bubonic plague in Wyoming

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For the third time in recent months, a cat has tested positive for bubonic plague in Wyoming, the state’s Department of Health reports. No human cases have been identified, but health officials warn the disease can be passed to people from infected animals.

 The most recent case involved a cat in the small town of Kaycee. Officials said the animal was known to wander outdoors. The disease was confirmed by the Wyoming State Veterinary Laboratory in Laramie.

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Evaluation of Five Pulicides to Suppress Fleas on Black-Tailed Prairie Dogs:

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1. Vector Borne Zoonotic Dis. 2019 Jan 8. doi: 10.1089/vbz.2018.2339. [Epub ahead of

print]
Evaluation of Five Pulicides to Suppress Fleas on Black-Tailed Prairie Dogs:
Encouraging Long-Term Results with Systemic 0.005% Fipronil.
Eads DA(1), Biggins DE(2), Bowser J(2), Broerman K(2), Livieri TM(3), Childers
E(4), Dobesh P(5), Griebel RL(5).
Author information:
(1)1 Department of Biology, Colorado State University, Fort Collins, Colorado.
(2)2 U.S. Geological Survey, Fort Collins Science Center, Fort Collins, Colorado.
(3)3 Prairie Wildlife Research, Wellington, Colorado.
(4)4 National Park Service, Badlands National Park, Interior, South Dakota.
(5)5 U.S. Forest Service, Wall, South Dakota.
Plague, a flea-borne disease, hampers efforts to restore populations of
black-footed ferrets (Mustela nigripes), which occupy colonies of prairie dogs
(Cynomys spp.) in North America. Plague is managed by infusing prairie dog
burrows with DeltaDust® 0.05% deltamethrin, a pulicide that kills fleas.
Experiments are needed to identify pulicides that can be used in rotation with
DeltaDust for integrated plague management. In South Dakota, USA, we tested the
efficacy of four pulicide dusts when applied at a rate of 8
g per burrow on
colonies of black-tailed prairie dogs (Cynomys ludovicianus): Sevin® 5% carbaryl;
Dusta-cide® 6% malathion; Alpine® 0.25% dinotefuran with 95% diatomaceous earth;
and Tri-Die® 1% pyrethrum with 40% amorphous silica and 10% piperonyl butoxide.
We also tested systemic 0.005% fipronil, which was distributed as
½
cup of laced
grain per burrow. We sampled prairie dogs on 3294 occasions and detected 10,041
fleas. Sevin and Dusta-cide suppressed fleas but only for 1 month. Neither Alpine
nor Tri-Die had any noticeable, consistent effect on fleas. Fipronil suppressed
fleas by 97-100% for 3 months. The residual effect of fipronil persisted for
∼
12
months. Efficacy of fipronil seems comparable with DeltaDust, which exhibited a
residual effect for
∼
10 months in prior studies. Continued research is needed to
optimize fipronil treatments for plague management on prairie dog colonies.
DOI: 10.1089/vbz.2018.2339
PMID: 30620249
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Parasitism of Black-Tailed Prairie Dogs by Linognathoides cynomyis (Phthiraptera: Polyplacidae).

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Abstract

The following study investigates louse parasitism of black-tailed prairie dogs (Cynomys ludovicianus (Ord, Rodentia: Sciuridae)) on 20 plots at 13 colonies in the short-grass prairie of New Mexico, USA, June-August, 2011-2012. Among 124 lice collected from 537 prairie dogs during 1,207 sampling events in which anesthetized animals were combed for ectoparasites, all of the lice were identified as Linognathoides cynomyis (Kim, Phthiraptera: Polyplacidae). Data were analyzed under an information-theoretic approach to identify factors predicting louse parasitism. Lice were most prevalent on plots with high densities of prairie dogs. At the scale of hosts, lice were most abundant on prairie dogs in poor body condition (with low mass:foot ratios) and prairie dogs harboring large numbers of fleas (Siphonaptera, mostly Oropsylla hirsuta (Baker, Siphonaptera: Ceratophyllidae) and Pulex simulans (Baker,Siphonaptera: Pulicidae)). Lice have been implicated as supplemental vectors of the primarily flea-borne bacterium Yersinia pestis (Yersin, Enterobacteriales: Yersiniaceae), a re-emerging pathogen that causes sylvatic plague in prairie dog populations. Coparasitism by lice and fleas, as found herein, might enhance plague transmission. L. cynomyis deserves attention in this context.

Read more:  Parasite

4,000-year-old genomes point to origins of bubonic plague

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Geneticists are a step closer to understanding how plague evolved into one of the great scourges of human history. Yersinia pestis, the bacterium that causes bubonic plague, spreads through the bites of infected fleas. In the flea’s gut, plague bacteria multiply until a mass of bacteria blocks the passage to the flea’s stomach. The starving flea bites a host and feeds frantically, but since it can’t swallow its meal, it ends up regurgitating blood and bacteria back into its prey’s bloodstream, spreading the disease to a new host.

Read more:  Plague

Impact of Sylvatic Plague Vaccine on Non-target Small Rodents in Grassland Ecosystems.

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Abstract

Oral vaccination is an emerging management strategy to reduce the prevalence of high impact infectious diseases within wild animal populations. Plague is a flea-borne zoonosis of rodents that often decimates prairie dog (Cynomys spp.) colonies in the western USA. Recently, an oral sylvatic plague vaccine (SPV) was developed to protect prairie dogs from plague and aid recovery of the endangered black-footed ferret (Mustela nigripes). Although oral vaccination programs are targeted toward specific species, field distribution of vaccine-laden baits can result in vaccine uptake by non-target animals and unintended indirect effects. We assessed the impact of SPV on non-target rodents at paired vaccine and placebo-treated prairie dog colonies in four US states from 2013 to 2015. Bait consumption by non-target rodents was high (70.8%, n = 3113), but anti-plague antibody development on vaccine plots was low (23.7%, n = 266). In addition, no significant differences were noted in combined deer mice (Peromyscus maniculatus) and western harvest mouse (Reithrodontomys megalotis) abundance or community evenness and richness of non-target rodents between vaccine-treated and placebo plots. In our 3-year field study, we could not detect a significant positive or negative effect of SPV application on non-target rodents.

Read more:  Vaccine

RESISTANCE TO DELTAMETHRIN IN PRAIRIE DOG ( CYNOMYS LUDOVICIANUS) FLEAS IN THE FIELD AND IN THE LABORATORY.

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Abstract

Sylvatic plague poses a substantial risk to black-tailed prairie dogs ( Cynomys ludovicianus) and their obligate predator, the black-footed ferret ( Mustela nigripes). The effects of plague on prairie dogs and ferrets are mitigated using a deltamethrin pulicide dust that reduces the spread of plague by killing fleas, the vector for the plague bacterium. In portions of Conata Basin, Buffalo Gap National Grasslands, and Badlands National Park, South Dakota, 0.05% deltamethrin has been infused into prairie dog burrows on an annual basis since 2005. We aimed to determine if fleas ( Oropsylla hirsuta) in portions of the Conata Basin and Badlands National Park have evolved resistance to deltamethrin. We assessed flea prevalence, obtained by combing prairie dogs for fleas, as an indirect measure of resistance. Dusting was ineffective in two colonies treated with deltamethrin for >8 yr; flea prevalence rebounded within 1 mo of dusting. We used a bioassay that exposed fleas to deltamethrin to directly evaluate resistance. Fleas from colonies with >8 yr of exposure to deltamethrin exhibited survival rates that were 15% to 83% higher than fleas from sites that had never been dusted. All fleas were paralyzed or dead after 55 min. After removal from deltamethrin, 30% of fleas from the dusted colonies recovered, compared with 1% of fleas from the not-dusted sites. Thus, deltamethrin paralyzed fleas from colonies with long-term exposure to deltamethrin, but a substantial number of those fleas was resistant and recovered. Flea collections from live-trapped prairie dogs in Thunder Basin National Grasslands, Wyoming suggest that, in some cases, fleas might begin to develop a moderate level of resistance to deltamethrin after 5-6 yr of annual treatments. Restoration of black-footed ferrets and prairie dogs will rely on an adaptive, integrative approach to plague management, for instance involving the use of vaccines and rotating applications of insecticidal products with different active ingredients.

Read more:  PubMed

Treatment of black-tailed prairie dog burrows with deltamethrin to control fleas (Insecta: Siphonaptera) and plague.

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Abstract

Burrows within black-tailed prairie dog (Cynomys ludovicianus) colonies on the Rocky Mountain Arsenal National Wildlife Refuge, Colorado, were dusted with deltamethrin insecticide to reduce flea (Insecta: Siphonaptera) abundance. Flea populations were monitored pre- and posttreatment by combing prairie dogs and collecting fleas from burrows. A single application of deltamethrin significantly reduced populations of the plague vector Oropsylla hirsuta, and other flea species on prairie dogs and in prairie dog burrows for at least 84 d. A plague epizootic on the Rocky Mountain Arsenal National Wildlife Refuge caused high mortality of prairie dogs on some untreated colonies, but did not appear to affect nearby colonies dusted with deltamethrin.

Read more: PubMed

SEASON OF DELTAMETHRIN APPLICATION AFFECTS FLEA AND PLAGUE CONTROL IN WHITE-TAILED PRAIRIE DOG (CYNOMYS LEUCURUS) COLONIES, COLORADO, USA.

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Abstract

In 2008 and 2009, we evaluated the duration of prophylactic deltamethrin treatments in white-tailed prairie dog ( Cynomys leucurus ) colonies and compared effects of autumn or spring dust application in suppressing flea numbers and plague. Plague occurred before and during our experiment. Overall, flea abundance tended to increase from May or June to September, but it was affected by deltamethrin treatment and plague dynamics. Success in trapping prairie dogs (animals caught/trap days) declined between June and September at all study sites. However, by September trap success on dusted sites (19%; 95% confidence interval [CI] 16-22%) was about 15-fold greater than on undusted control sites (1%; CI 0.3-4%; P≤0.0001). Applying deltamethrin dust as early as 12 mo prior seemed to afford some protection to prairie dogs. Our data showed that dusting even a portion of a prairie dog colony can prolong its persistence despite epizootic plague. Autumn dusting may offer advantages over spring in suppressing overwinter or early-spring flea activity, but timing should be adjusted to precede the annual decline in aboveground activity for hibernating prairie dog species. Large colony complexes or collections of occupied but fragmented habitat may benefit from dusting some sites in spring and others in autumn to maximize flea suppression in a portion of the complex or habitat year-round.

Read more:  PubMed

Flea abundance, diversity, and plague in Gunnison’s prairie dogs (Cynomys gunnisoni) and their burrows in montane grasslands in northern New Mexico.

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Abstract

Plague, a flea-transmitted infectious disease caused by the bacterium Yersinia pestis, is a primary threat to the persistence of prairie dog populations (Cynomys spp.). We conducted a 3-yr survey (2004-2006) of fleas from Gunnison’s prairie dogs (Cynomys gunnisoni) and their burrows in montane grasslands in Valles Caldera National Preserve in New Mexico. Our objectives were to describe flea communities and identify flea and rodent species important to the maintenance of plague. We live-trapped prairie dogs and conducted burrow sweeps at three colonies in spring and summer of each year. One hundred thirty prairie dogs and 51 golden-mantled ground squirrels (Spermophilus lateralis) were captured over 3,640 trap nights and 320 burrows were swabbed for fleas. Five flea species were identified from prairie dogs and ground squirrels and four were identified from burrow samples. Oropsylla hirsuta was the most abundant species found on prairie dogs and in burrows. Oropsylla idahoensis was most common on ground squirrels. Two colonies experienced plague epizootics in fall 2004. Plague-positive fleas were recovered from burrows (O. hirsuta and Oropsylla tuberculata tuberculata) and a prairie dog (O. hirsuta) in spring 2005 and summer 2006. Three prairie dogs collected in summer 2005 and 2006 had plague antibody. We found a significant surge in flea abundance and prevalence, particularly within burrows, following plague exposure. We noted an increased tendency for flea exchange opportunities in the spring before O. hirsuta reached its peak population. We hypothesize that the role of burrows as a site of flea exchange, particularly between prairie dogs and ground squirrels, may be as important as summer conditions that lead to buildup in O. hirsuta populations for determining plague outbreaks.

Read more:  PubMed

Burrow Dusting or Oral Vaccination Prevents Plague-Associated Prairie Dog Colony Collapse.

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Abstract

Plague impacts prairie dogs (Cynomys spp.), the endangered black-footed ferret (Mustela nigripes) and other sensitive wildlife species. We compared efficacy of prophylactic treatments (burrow dusting with deltamethrin or oral vaccination with recombinant “sylvatic plague vaccine” [RCN-F1/V307]) to placebo treatment in black-tailed prairie dog (C. ludovicianus) colonies. Between 2013 and 2015, we measured prairie dog apparent survival, burrow activity and flea abundance on triplicate plots (“blocks”) receiving dust, vaccine or placebo treatment. Epizootic plague affected all three blocks but emerged asynchronously. Dust plots had fewer fleas per burrow (P < 0.0001), and prairie dogs captured on dust plots had fewer fleas (P < 0.0001) than those on vaccine or placebo plots. Burrow activity and prairie dog density declined sharply in placebo plots when epizootic plague emerged. Patterns in corresponding dust and vaccine plots were less consistent and appeared strongly influenced by timing of treatment applications relative to plague emergence. Deltamethrin or oral vaccination enhanced apparent survival within two blocks. Applying insecticide or vaccine prior to epizootic emergence blunted effects of plague on prairie dog survival and abundance, thereby preventing colony collapse. Successful plague mitigation will likely entail strategic combined uses of burrow dusting and oral vaccination within large colonies or colony complexes.

Read More:  PubMed

Plague in a Colony of Gunnison’s Prairie Dogs ( Cynomys gunnisoni) Despite Three Years of Infusions of Burrows with 0.05% Deltamethrin to Kill Fleas.

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Abstract

  At Valles Caldera National Preserve in New Mexico, US, infusing Gunnison’s prairie dog ( Cynomys gunnisoni) burrows with an insecticide dust containing 0.05% deltamethrin killed fleas which transmit bubonic plague. The reduction in the number of fleas per prairie dog was significant and dramatic immediately after infusions, with a suggestion that the reduction persisted for as long as 12 mo. Despite the lower flea counts, however, a plague epizootic killed >95% of prairie dogs after 3 yr of infusions (once per year). More research is necessary for a better understanding of the efficacy of insecticide dusts at lowering flea counts and protecting prairie dogs from plague.

PMID:
29286262
DOI:
10.7589/2017-04-089

Read more:  PubMed

Return of BLACK DEATH? Scientists uncover PLAGUE in soil and water after over 200 DEATHS

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DEADLY bacteria that triggers a plague could be hiding in soil and water sources across the globe, causing a serious risk to the public’s health, after the disease tore across Madagascar last year killing 202 people, it has been claimed.

By Thomas Mackie
There have also been outbreaks in the US, with 16 cases including four deaths in 2015.

Read more:  Plague

Medieval diseases are making a grim comeback

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The Black Death was little short of a bacterial apocalypse. The outbreak of bubonic plague, imported along the Silk Road, is thought to have killed between 25m and 50m people as it rampaged through 14th-century Europe. The disease thence resurfaced sporadically: the Great Plague of London, for example, felled a fifth of city dwellers in the 1660s.

While the plague seems to us a medieval affliction, it has never fully disappeared. On average, about 500 cases are documented globally each year, mostly in Africa, South America and India. The infection is treatable with antibiotics if caught early.

Read More:  Plague

3 People Have Caught Plague in New Mexico This Month

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Three people in New Mexico have been infected with plague this month, which is close to the number of plague cases that the state saw in all of 2016, according to health officials.

This week, the New Mexico Department of Health (NMDOH) reported two cases of plague — one in a 52-year-old woman and one in a 62-year-old woman, both living in Santa Fe County, in the northern part of the state. Earlier in June, the state reported a case of plague in a 63-year-old man, also living in Santa Fe County. All three people were hospitalized, but all of them survived, NMDOH officials said.

Read more:  Plague

 

 

Fleas that bite rodents infected with the bacteria that cause the plague can transmit the disease to people.

Credit: Janice Haney Carr/CDC

 

Expansion of prairie dog vaccine proposed

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Use of an oral vaccine that protects prairie dogs from the plague will be expanded on the Charles M. Russell and UL Bend National Wildlife Refuges in Montana under a plan proposed by the U.S. Fish and Wildlife Service.

The new plan would allow for vaccine distribution on wilderness areas within the refuges and on nearby private lands when requested by landowners. The Service has completed an environmental assessment for the action and is seeking public comment on the proposal.

Read more:  Vaccine

Swabbing Prairie Dog Burrows for Fleas That Transmit Yersinia pestis: Influences on Efficiency.

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This message contains search results from the National Center for Biotechnology Information (NCBI) at the U.S. National Library of Medicine (NLM). Do not reply directly to this message

Sent on: Sun May 14 05:04:19 2017

1 selected item: 28486652

PubMed Results

Item 1 of 1    (Display the citation in PubMed)

1. J Med Entomol. 2017 May 9. doi: 10.1093/jme/tjx090. [Epub ahead of print]

Eads DA1.

Author information:

1Department of Biology, Colorado State University, Fort Collins, CO 80523 (daeads@colostate.edu).

Abstract

Scientists and health-care professionals sometimes use a swabbing technique to collect fleas from rodent burrows, and later test the fleas for Yersinia pestis, the causative agent of plague. Detection of Y. pestis is enhanced when large pools of fleas are available. The following study investigated factors that might affect the rate at which fleas are collected from burrows in colonies of black-tailed prairie dogs (Cynomys ludovicianus). Data were collected from 13 colonies in New Mexico during 0600-1000 hours, June-August 2010-2011. Fleas were scarce on swabs inserted into burrows that were not actively used by prairie dogs; fleas are presumably suppressed in burrows that are void of hosts and might have begun to collapse due to a lack of maintenance. Fleas were scarce on swabs inserted into burrows with little sunlight entering the tunnel; many species of fleas use changes in light intensity to locate objects, but if light is limited, it might be difficult to locate a swab. Fleas were scarce on swabs inserted to shallow depths underground, especially during hot mornings, and during the hottest portions of mornings; when conditions are hot above ground, ectothermic fleas might migrate into the deep components of burrows, or become less willing to jump onto hosts, making it difficult to collect the fleas with swabs. If the swabbing technique is used to survey for Y. pestis on colonies of black-tailed prairie dogs, investigators might use the results of this study to modify their methods and increase the number of fleas collected.

© The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
PMID: 28486652
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Responses of Juvenile Black-Tailed Prairie Dogs ( Cynomys ludovicianus ) to a Commercially Produced Oral Plague Vaccine Delivered at Two Doses.

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This message contains search results from the National Center for Biotechnology Information (NCBI) at the U.S. National Library of Medicine (NLM). Do not reply directly to this message

Sent on: Sun May 7 04:19:27 2017

1 selected item: 28463626

PubMed Results

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1. J Wildl Dis. 2017 May 2. doi: 10.7589/2017-02-033. [Epub ahead of print]

Responses of Juvenile Black-Tailed Prairie Dogs ( Cynomys ludovicianus ) to a Commercially Produced Oral Plague Vaccine Delivered at Two Doses.

Cárdenas-Canales EM1, Wolfe LL1, Tripp DW1, Rocke TE2, Abbott RC2, Miller MW1.

Author information:

11 Colorado Division of Parks and Wildlife, Wildlife Health Program, Foothills Wildlife Research Facility, 4330 Laporte Ave., Fort Collins, Colorado 80521-2153, USA.22 United States Geological Survey, National Wildlife Health Center, 6006 Schroeder Road, Madison, Wisconsin 53711, USA.

Abstract

We confirmed safety and immunogenicity of mass-produced vaccine baits carrying an experimental, commercial-source plague vaccine (RCN-F1/V307) expressing Yersinia pestis V and F1 antigens. Forty-five juvenile black-tailed prairie dogs ( Cynomys ludovicianus ) were randomly divided into three treatment groups (n=15 animals/group). Animals in the first group received one standard-dose vaccine bait (5×107 plaque-forming units [pfu]; STD). The second group received a lower-dose bait (1×107 pfu; LOW). In the third group, five animals received two standard-dose baits and 10 were left untreated but in contact. Two vaccine-treated and one untreated prairie dogs died during the study, but laboratory analyses ruled out vaccine involvement. Overall, 17 of 33 (52%; 95% confidence interval for binomial proportion [bCI] 34-69%) prairie dogs receiving vaccine-laden bait showed a positive anti-V antibody response on at least one sampling occasion after bait consumption, and eight (24%; bCI 11-42%) showed sustained antibody responses. The STD and LOW groups did not differ (P≥0.78) in their proportions of overall or sustained antibody responses after vaccine bait consumption. Serum from one of the nine (11%; bCI 0.3-48%) surviving untreated, in-contact prairie dogs also had detectable antibody on one sampling occasion. We did not observe any adverse effects related to oral vaccination.
PMID: 28463626

Burrowing Owls, Pulex irritans, and Plague.

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This message contains search results from the National Center for Biotechnology Information (NCBI) at the U.S. National Library of Medicine (NLM). Do not reply directly to this message

Sent on: Sat Apr 22 08:14:51 2017

1 selected item: 26367482

PubMed Results

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1. Vector Borne Zoonotic Dis. 2015 Sep;15(9):556-64. doi: 10.1089/vbz.2015.1772. Epub 2015 Sep 14.

Belthoff JR1, Bernhardt SA2, Ball CL3, Gregg M4, Johnson DH5, Ketterling R6, Price E7, Tinker JK7.

Author information:

11 Department of Biological Sciences and Raptor Research Center, Boise State University , Boise, Idaho.22 Department of Biology, Utah State University , Logan, Utah.33 Idaho Bureau of Laboratories , Boise, Idaho.44 US Fish and Wildlife Service, Mid-Columbia River National Wildlife Refuge Complex , Burbank, Washington.55 Idaho Cooperative Fish and Wildlife Research Unit, University of Idaho, Moscow, Idaho and Global Owl Project , Alexandria, Virginia.66 Idaho Bureau of Laboratories and Idaho State University , Boise, Idaho.77 Department of Biological Sciences, Boise State University , Boise, Idaho.

Abstract

Western Burrowing Owls (Athene cunicularia hypugaea) are small, ground-dwelling owls of western North America that frequent prairie dog (Cynomys spp.) towns and other grasslands. Because they rely on rodent prey and occupy burrows once or concurrently inhabited by fossorial mammals, the owls often harbor fleas. We examined the potential role of fleas found on burrowing owls in plague dynamics by evaluating prevalence of Yersinia pestis in fleas collected from burrowing owls and in owl blood. During 2012-2013, fleas and blood were collected from burrowing owls in portions of five states with endemic plague-Idaho, Oregon, Washington, Colorado, and South Dakota. Fleas were enumerated, taxonomically identified, pooled by nest, and assayed for Y. pestis using culturing and molecular (PCR) approaches. Owl blood underwent serological analysis for plague antibodies and nested PCR for detection of Y. pestis. Of more than 4750 fleas collected from owls, Pulex irritans, a known plague vector in portions of its range, comprised more than 99.4%. However, diagnostic tests for Y. pestis of flea pools (culturing and PCR) and owl blood (PCR and serology) were negative. Thus, even though fleas were prevalent on burrowing owls and the potential for a relationship with burrowing owls as a phoretic host of infected fleas exists, we found no evidence of Y. pestis in sampled fleas or in owls that harbored them. We suggest that studies similar to those reported here during plague epizootics will be especially useful for confirming these results.
PMID: 26367482 [Indexed for MEDLINE]
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Verify: Prairie dogs, the plague and you

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OK it’s rare, but how deadly is it if you catch it?

The plague was lethal in Europe during the Middle Ages, “but now it’s different. We have a lot fewer cases in humans,” Chase said.

And we have antibiotics to treat the illness if you do happen to catch it.

The deadliness of the disease depends on which strain you have.

The most common is the bubonic plague. Chase said this strain is treatable with antibiotics.

Septicemic plague is when the bacteria enters the bloodstream. This is a rare but serious form of the plague and is usually fatal without treatment.

And then there’s pneumonic plague, which is when the bacteria gets in your lungs.

“That is almost always fatal if it’s not treated right away,” Chase said.

All good information, but remember it is a course of intravenous antibiotics that is needed. If you have symptoms and suspect you may have been infected to the the Emergency Room, and not your GP or urgent care.

 

Read More:  Plague

3 dogs test positive for plague in East Mountains

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EDGEWOOD, N.M. (KRQE) – Three dogs tested positive for plague in the East Mountains.

State health officials say the dogs were from within several miles of Edgewood, but say Bernalillo and Santa Fe counties are also affected.

Plague is a bacterial disease transmitted by infected fleas and rodents.

Officials recommend cleaning near the house where rodents could live, such as woodpiles and abandoned cars.

East Mountains

Dog Infects Humans With Plague for First Time in US

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Health officials told ABC News that this the first report of a dog infecting a human with the plague in the U.S.

The dog, a 2-year-old American pit bull terrier, became sick last summer with a fever and jaw rigidity, among other symptoms. The dog’s health declined so quickly that it was euthanized the following day at a local vet’s office, health officials said.

Read more:  Dogs

RESEARCHERS FINDING SUCCESS FIGHTING PLAGUE IN PRAIRIE DOG COLONIES

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GUNNISON, Colo. – Work to protect the Gunnison’s prairie dog by Colorado Parks and Wildlife has proven successful during the last four years and biologists are continuing with more research to improve methods to sustain populations.

“In some situations prairie dogs can be seen as pests, but they are critical in the environment and help to promote survival of numerous other species such as burrowing owls, badgers and raptors,” said Dan Tripp, a wildlife disease researcher with Colorado Parks and Wildlife.

In Colorado there are three species of prairie dogs. The Gunnison’s prairie dog resides primarily in the southwest portion of the state. The others are the white-tailed prairie dog which lives mainly in northwestern Colorado, and the black-tailed prairie dog which inhabits areas along the Front Range and eastern plains.

Plague, caused by a non-native bacteria carried by fleas, has been identified as a threat to the stability of Gunnison’s prairie dog populations in Colorado. Outbreaks of plague frequently kill every prairie dog in a colony. To treat the sickness, agency scientists are spraying prairie dog burrows with a flea-killing pesticide powder. Researchers are also testing the efficiency of oral vaccination baits for preventing plague in animals. Even though researchers are conducting trials to develop potentially useful vaccinations, such tests and investigations require government funding to be carried out. Several steps in the procedure necessitate the purchase of 25l distilled water in bulk in order to clean the equipment, such as beakers, test tubes, and other lab apparatus. Aside from that, funds are required to purchase chemicals and drugs for testing. That is why it is always said that with government support only, vaccines for different illnesses, including the plague, may be effectively created.

It’s interesting to know that the bacteria that causes plague was transported to North America around 1900 and was subsequently found in Colorado around 1940. Because prairie dogs did not evolve with the bacteria, they carry little immunity to fight off the disease.

“The plague bacteria is a non-native invasive species that devastates prairie dogs and other wildlife species. We’re not attempting to upset nature’s balance with these treatments. We are working to restore balance in the environment and reduce the risk of major plague outbreaks in prairie dog colonies,” Tripp said. “We lose a lot of resilience in the environment when we lose prairie dogs.”

Controlling plague in prairie dogs may also help limit potential exposure to people and their pets.

In 2010, CPW biologists started dusting some burrows in the Gunnison Basin with an insecticide that kills fleas. The experiment has worked. In some cases, nearby colonies that were not dusted were wiped out by plague while colonies that were dusted remain healthy. Biologists also said that they’re seeing many more prairie dogs in more areas in the basin this year compared to five years ago.

Although the insecticide is not harmful to other species, applying it is labor intensive and expensive. For dusting to be effective every burrow in a colony must receive an application annually.

A potentially promising treatment is the oral sylvatic plague vaccine, Tripp said. Developed by the U.S. Geological Survey’s National Wildlife Health Center, the vaccine-still in the experimental stage-works well in the laboratory. It is administered in a cube flavored with peanut butter. The baits also contain a red dye that adheres to animals’ coats which helps researchers track the prairie dogs that eat the bait. This is only the second year that the vaccine has been tested in the field in Colorado. Longer term monitoring will be needed to determine its efficacy.

“So far, we’re encouraged by the results and we are optimistic that the vaccine will be effective in limiting future plague outbreaks,” Tripp said.

In the Gunnison area, four prairie dog colonies are being used for vaccine testing. Two colonies are receiving the vaccine bait, two are receiving no treatment. In Teller County the test is being conducted with two colonies.

The vaccine is also being tested in Arizona, Montana, South Dakota, Texas, Utah, and Wyoming. The experiment will continue for another two years and is a collaborative effort among more than 30 federal, state and tribal agencies and nongovernmental organizations.

In Colorado, the vaccine research in Gunnison’s prairie dogs is occurring on public land-state wildlife areas, BLM and National Park Service property.

Contrary to public perception, prairie dogs don’t reproduce prolifically. Females have only one litter of 3-5 pups each year and the natural mortality rate of the young is about 50 percent. Consequently, the colonies generally do not spread rapidly over wide areas. Tripp explained that few connections between colonies across a landscape exist; so when a colony is wiped out it may have little chance of being re-colonized.

“By preventing plague we can have healthy, stable prairie dog colonies that we can manage on public lands,” Tripp said.

The conservation work is aimed at preserving the ecological niche of prairie dogs and preventing a listing of the Gunnison’s prairie dog under the federal Endangered Species Act. If the animal is listed it could lead to various land-use restrictions.

J Wenum, area wildlife manager in Gunnison, explained that when landscapes are restored to a more natural condition, more uses can be accommodated.

“If you have healthy, functioning landscapes you don’t have to be focused on limiting uses,” Wenum said. “A healthy landscape will accommodate agriculture, recreation and wildlife.”

The testing of the oral vaccine will continue for a few more years, and biologists are cautiously optimistic that the vaccine will prove to be effective at limiting plague.

“We won’t be able to prevent plague in every colony. But this work will help to stabilize the overall population at its current distribution and benefit this important species,” Tripp said.

For more information about prairie dogs and other wildlife species, see cpw.state.co.us.

With 150 species of mammals, New Mexico is prone to plague fleas

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New Mexico has 150 known species of mammals, one of the highest numbers in the country. Eighty-two species of mammals are known to be hosts of fleas. We have 107 species of fleas in New Mexico.

We have plenty of mammals and plenty of fleas. This can be a big worry for homeowners who may get fleas into their homes if a prairie dog comes into their home or they have had contact with a person who has unknowingly transported them into their house. If this was to happen then calling in a pest control company like https://www.pestcontrolexperts.com/local/alabama/ or one in closer proximity, will help them get rid of these fleas and keep their house safe from a severe infestation.

Several dogs in New Mexico have been diagnosed with plague. Plague is primarily a disease of wild animals, especially rodents. Some species are particularly susceptible. Prairie dogs, particularly the Gunnison’s prairie dog, are uniformly susceptible to fatal infections of the plague, and large proportions or even entire populations have been destroyed in a single plague event.

Plague is caused by the bacterium Yersinia pestis. It is of Old World origin and throughout history has been referred to as “Black Death.”

Plague was first discovered in North America from California ground squirrels in 1905 and first detected in New Mexico rodents in 1938. As of 1982, 18 species of rodents, two species of rabbits and nine species of carnivores have been infected by plague in New Mexico.

Plague is spread by fleas. The normal cycle of plague transmission is between wild rodents and their fleas in nature. When fleas ingest bacteria along with blood from infected rodents, the bacteria multiply rapidly in the gut of the flea. New Mexico has a high case rate of plague. For example, during 1988-2002, 112 human cases of plague were reported from 11 Western states. The majority, 97, of the cases were in Arizona, California, Colorado and New Mexico and 48 of those cases were from New Mexico.

 

Read More: Bugman

Praire dog plague

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PIERRE, S.D. (AP) — Sylvatic plague that has devastated prairie dog colonies across western South Dakota since 2007 has spread north and east, and the disease is now affecting colonies in the Fort Pierre National Grassland image1in the central part of the state.

Prairie dog towns are becoming fewer and farther between, grassland wildlife biologist Ruben Mares told the Capital Journal (http://bit.ly/1jep2Wz ). Last year, one colony he monitors had shrunk from 30 acres to 5 acres, he said.

Read more:  Plague

SEASON AND APPLICATION RATES AFFECT VACCINE BAIT CONSUMPTION BY PRAIRIE DOGS IN COLORADO AND UTAH, USA.

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Abstract

Abstract

Plague, a zoonotic disease caused by the bacterium Yersinia pestis, causes high rates of mortality in prairie dogs (Cynomys spp.). An oral vaccine against plague has been developed for prairie dogs along with a palatable bait to deliver vaccine and a biomarker to track bait consumption. We conducted field trials between September 2009 and September 2012 to develop recommendations for bait distribution to deliver plague vaccine to prairie dogs. The objectives were to evaluate the use of the biomarker, rhodamine B, in field settings to compare bait distribution strategies, to compare uptake of baits distributed at different densities, to assess seasonal effects on bait uptake, and to measure bait uptake by nontarget small mammal species. Rhodamine B effectively marked prairie dogs’ whiskers during these field trials. To compare bait distribution strategies, we applied baits around active burrows or along transects at densities of 32, 65, and 130 baits/ha. Distributing baits at active burrows or by transect did not affect uptake by prairie dogs. Distributing baits at rates of ≥65/ha (or ≥1 bait/active burrow) produced optimal uptake, and bait uptake by prairie dogs in the autumn was superior to uptake in the spring. Six other species of small mammals consumed baits during these trials. All four species of tested prairie dogs readily consumed the baits, demonstrating that vaccine uptake will not be an obstacle to plague control via oral vaccination.

More:  Plague

States test a new prairie dog plague vaccine

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Dressed in long pants, long-sleeve shirts and closed-toed shoes, a team of researchers from Colorado Parks and Wildlife 5eb1329b-258e-4e6f-8187-8e76aae44b8dgathered in a sagebrush-grass meadow near Gunnison, Colo. this summer, each with a GPS in hand. Lining up 10 meters apart along the border of a virtual grid, they walked straight lines over a Gunnison’s prairie dog colony and dropped quarter-sized peanut butter cubes behind them. It was one of three Gunnisons colonies where the delectable cubes became just a treat for any animal that found them, but at another three, the cubes contained a vaccine against sylvatic plague, which has ravaged the West’s prairie dog populations.

Read more:  Plague

Prairie Dogs FAQ

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750px-Prairiehondjes1Prairie dogs are burrowing rodents who live on the plains of North and Central America. They were first documented by Lewis and Clark in their 1804 journals from their journey across the United States. Lewis recognized the similarity between prairie dogs and squirrels (both rodents) and called it the barking squirrel.

Prairie dogs belong to the order Rodentia, the family Sciuridae (along with squirrels and chipmunks), and the genus Cynomys (which means “mouse dog”).

Within that genus are a number of species, including the Gunnison’s prairie dog (Cynomys gunnisoni), the white-tailed prairie dog (Cynomys leucurus), the black-tailed prairie dog (Cynomys ludovicianus), the Mexican prairie dog (Cynomys mexicanus) and the Utah prairie dog (Cynomys parvidens).

Gunnison’s Prairie Dogs live in Utah, Colorado, New Mexico and Arizona. Gunnison’s prairie dogs hibernate from November through March. They are yellow-tan in color, slightly paler than other prairie dog species, and have a short white-tipped tail.

In early 2008, the U.S. Fish and Wildlife Service determined that populations of the Gunnison’s prairie dog located in central and south-central Colorado and north-central New Mexico are warranted for protection under the Endangered Species Act, but they could not be listed as endangered because they were deemed a lower priority than other species.

Today, Gunnison’s prairie dogs have no form of federal protection whatsoever. The only exception to this is a protected colony living in Petrified Forest National Park.

DO PRAIRIE DOGS DRINK WATER?

Not usually, but they will. In the wild, they get enough moisture from the native grasses and weeds that they normally eat. In Albuquerque during a drought, they will eat cactus to receive their needed moisture and to prevent starvation. Supplemental water is needed in barren areas and during drought conditions.

IS IT OK TO FEED THEM?

If they have native grasses and weeds (even goathead greens) they don’t need to be fed. However, if their area is barren of foods native to their diet it is ok to feed them. Grass cuttings and alfalfa are the closest foods to their natural diet. Sweets are not natural for them but they love sunflower seeds, corn on the cob, lettuce, peaches, strawberries, watermelon and apples. They don’t like broccoli, zucchini and potatoes.

Picture 449WHY DO THEY NEED POPULATION CONTROL AND WHERE DO YOU TAKE THEM?

“City” prairie dogs are trapped in small areas and have no predators other than man and automobiles to maintain their population. Eventually they reach maximum population and must be thinned out on parkland in Albuquerque. They are relocated by our volunteers to a refuge south of the city. The ideal time is in June, July or August although they can be relocated in April before the babies are born.

DON’T THEY CARRY THE PLAGUE?

Plague is not carried by prairie dogs but by fleas that can infect all mammals. If a prairie dog is infected by plague carrying fleas, it, and the whole colony, will die. According to the Environmental Health Department, they are not carriers of the Hanta Virus. If prairie dogs are “frisky”, they are healthy.

CAN THEY TRANSMIT RABIES?

While all mammals are believed to be susceptible to rabies, there have been no recorded cases of prairie dogs transmitting rabies to humans. Most likely the animal is killed in the initial attack by a rabid animal, or dies shortly thereafter, before it can develop rabies. Never the less any rabid animal is potentially capable of rabies virus transmission. If the prairie dogs appear to be “frisky” they are most likely healthy and free of disease. Regardless of their condition, prairie dogs, like other wild animals, should not be handled.

WHAT KIND OF PRAIRIE DOGS LIVE IN ALBUQUERQUE?

Gunnisons or white-tailed which are one of five species of ground squirrels. The Black-tailed prairie dogs are no longer found in the Albuquerque area.

DO PRAIRIE DOGS HIBERNATE?

The Gunnison prairie dogs in Albuquerque do … Usually between November and March. Black-tailed prairie dogs do not.

HOW OFTEN DO PRAIRIE DOGS HAVE BABIES?

The usual litter is 3 to 5 pups once a year in May. The babies come above ground in June and begin to eat grasses and weeds instead of nursing. Only about 50% will survive more than 6 months.

Find out more about them by visiting some of our fact sheets here and here and here!

Gunnison’s Prairie Dogs

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Description: Yellowish buff mixed with black above, slightly paler below. Short, white-tipped tail. Terminal half of tail grayish white in center. 12-14″ in height, weighing 23-42 ounces. Lives 3-5 years in the wild, longer in captivity.

Similar Species: White-tailed and Utah prairie dogs have white in center of tail rather than grayish. Black-tailed Prairie Dog’s tail has black tip.

Breeding: 1 litter per year of 1–8 young, born in early May; gestation 27–33 days, pups emerge mid June.

Habitat: Short grass prairies in high mountain valleys and plateaus of southern Rocky Mountains at elevations of 6,000–12,000’ (1,800–3,600 m). Habitat is much more variable topographically and vegetationally than that of the Black-tailed Prairie Dog, which occurs at lower elevations.

Range: Southeastern Utah, south and central Colorado, northeast and central Arizona, and northwest New Mexico.

Discussion: The Gunnison’s Prairie Dog, like the rest of its kin, is active only when the sun is up, and is most energetic near dawn and dusk. It is constantly vigilant while aboveground, often sitting upright on its hind feet while it pursues its main activities: mainly feeding, but also grooming and playing. This animal generally is seen from April to October. It hibernates (torpor) in winter, living on stored body fat. It usually emerges in April, though they will emerge earlier if the winter is mild. Gunnison’s Prairie Dog feeds on green vegetation, particularly grasses, but also forbs, sedges, and shrubs, as well as a few insects. Its colonies are generally smaller and less closely knit than those of other prairie dogs, resembling ground squirrel aggregations, with fewer than 50 to 100 individuals. The animals in the colony cannot always see one another because their habitat is in such varied and patchy terrain, which is caused in part by human activities. On flat ground and where this prairie dog is protected colonies are much larger and more extensive. This species’ burrow systems can be up to 80 feet long and 16 feet deep in well-established colonies. Burrows can have food storage, flood, nesting, communal and excrement chambers. Territoriality is not well developed in Gunnison’s Prairie Dog, although old males may defend small areas outside their burrows. Mother-young relationships form the basic social unit. Newborns remain in the burrow about three weeks before emerging and are weaned about three weeks later. The female sits almost straight up on her haunches to nurse her young, who suckle either pectoral or inguinal (hind leg) nipples. Gunnison’s alarm call, distinctive among prairie dogs, is important to the survival and structure of the community. It is a series of high-pitched barks of one or two distinct syllables, with the second syllable lower and more guttural. The call may be repeated frequently and may continue for as long as half an hour. It increases in intensity as danger escalates, and ends in chatter as the animal enters its burrow. Predators include American Badgers, Coyotes, weasels, and raptors. Plague (Yersina pestis), carried by fleas, can decimate populations of this species. However, humans, through their extermination programs, are the chief enemy of Gunnison’s Prairie Dog.

About Prairie Dogs

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My goal in writing this article is to help educate people about prairie dogs, and to provide people with objective information backed by valid scientific research. As many of us in New Mexico live among prairie dogs, I feel it is especially critical that people are well educated about these native animals.

What are prairie dogs?

Prairie dogs are large, colonial, ground-nesting squirrels. They live in large communities (colonies) in grassland habitats. They are highly social animals, and have evolved a complex language system. Prairie dogs eat grasses and weeds, and they will clip grasses to enable them to detect predators. They live in family units called coteries that consist of usually one male and several females. Females often remain in the same burrow system during their lifetime and juvenile males leave the burrow during their first year. Prairie dogs usually live for about 5 years in the wild.

What species do we have in New Mexico?

Both black-tailed prairie dogs and Gunnison’s prairie dogs occur within New Mexico.

Black-tailed prairie dogs are the most social of all the prairie dog species, and occur in the Great Plains region. They used to be common in the eastern and southwestern part of New Mexico, but have been eliminated from most of their native habitat within the state.

Gunnison’s prairie dogs occur throughout the four corners region and are found in Santa Fe, Albuquerque, Socorro, Gallup, and Grants. Gunnison’s prairie dogs also have declined significantly, and have been petitioned to be listed under the endangered species list.

Prairie dog reproduction

Prairie dogs are not prolific breeders. They only have one litter per year, consisting of about four young, of which only two usually survive.

The ecological role of prairie dogs

Prairie dogs were once among the most numerous and widespread herbivores in North American grasslands. Human activities such as habitat destruction and poisoning efforts have significantly reduced prairie dog populations. Three of the five species are federally listed as threatened or endangered. The most widespread species, the black-tailed prairie dog, now occupies less than 2% of its historical range. Scientists studying prairie dogs have estimated that at least 163 animal species are associated with prairie dog colonies, indicating that the prairie dog is a “keystone” (i.e., critically important) species in these ecosystems. Prairie dogs create ecological disturbances resulting in a diverse landscape that provides a variety of habitats for many plant and animal species, including black-footed ferrets, rabbits, squirrels, lizards, snakes, burrowing owls, and invertebrates. Prairie dogs also affect grassland plant species composition and vegetation structure and enhance soil and plant nutritional quality, which benefits antelope, bison, and cattle.

Prairie dog eradication has caused significant biological degradation and decline in biological diversity on grasslands in North America. Research has found that prairie dogs inhibit woody plants from invading grasslands, and has indicated that the elimination of these rodents has played a significant role in desertification of grasslands. In addition, removal of prairie dogs causes secondary extinctions of other species, altering the entire food web associated with prairie dogs. For example, the black-footed ferret, burrowing owl, mountain plover, and ferruginous hawk are among the most endangered prairie dog-dependent species. Despite their importance, people often want to exterminate prairie dogs because of misconceptions about proliferation, children being bitten, destruction of landscaped areas, plague, competition for forage with livestock, and animals breaking their legs in the burrows.

Are they dangerous to humans?

Prairie dogs are not a threat to children. They are timid animals, and when approached by humans, prairie dogs quickly scurry into the safety of their burrows. People should never hand feed prairie dogs or try to grab them. Hand feeding may cause the animals to be accustomed to humans, and result in bites when humans get too close.

Prairie dogs and hantavirus

Prairie dogs are not known to contract or transmit hantaviruses. Worldwide, hantaviruses are associated with deer mice and other rodents in the family Muridae, which are distant relatives of prairie dogs (Squirrels, in the family Sciuridae).

Prairie dogs and plague

Prairie dogs do not carry plague. Plague is a non-native disease, introduced to North America from Europe by humans. Prairie dogs have not evolved immunity to plague, and therefore, it kills 99% of the individuals in an infected colony. Plague has been a major contributor to causing the decline in prairie dog populations.

Fleas carry the plague. These fleas can be found on many wild animals, and are not limited to prairie dogs. Killing prairie dogs just causes fleas to search for another host, and is not recommended by the Center for Disease Control (CDC) as an effective method of plague control. The key to preventing plague is to control fleas, not prairie dogs. Avoiding contact with dead wild animals and dusting pets and rodent burrows with flea powder can successfully prevent plague. Plague is also easily overcome with antibiotics when detected early, so people should educate themselves about the symptoms of plague. A colony of active prairie dogs is indicative of healthy, plague-free prairie dogs, and should not cause concern.

What if they are damaging the landscape in your yard?

If prairie dogs are causing damage to landscaped areas, you can use visual barriers such as vegetation or low walls and additional below ground barriers to contain the animals. Prairie dogs are highly discouraged by tall vegetation, so plant native shrubs and do not mow native grasses. Xeriscaping the area will also help discourage prairie dogs, and conserve water.

How to get rid of prairie dogs

Rat poison should not be used to kill prairie dogs because it causes secondary poisoning of dogs, cats, and other animals, and is dangerous to children. The only legal method for killing prairie dogs involves the use of poisonous gas by licensed professionals (in most states), which is costly. The poisonous gases used are inhumane, causing slow and painful deaths, and can take up to 72 hours to induce death in an animal. During which time the animals suffer from burning of the mucus membranes to paralysis.

The best recommendation is to learn to live with these native animals, and, if for some reason, prairie dogs must be removed, you can contact professional relocators in the state that can be referred by People for Native Ecosystems (PNE) (505) 982-0496 or the City of Santa Fe Permit Development and Review (505) 955-6480. Prairie Dog Pals of Albuquerque also conducts some relocations, though mostly on public lands.

Shooting prairie dogs

Shooting is often used as a means of reducing the size of a prairie dog colony. Varmint hunters gather together in many states where prairie dogs occur to shoot them. They do not eat the prairie dogs; rather, they shoot them with rifles for target practice fun. In our national grasslands, bullet shells and literally exploded prairie dogs can be found littering the colonies. It is important to keep in mind that that these are highly social animals that are greatly affected by the shooting of their family members. Prairie dogs have become threatened species and are not prolific breeders, so sport shooting should be banned.

Do prairie dogs compete with cattle for forage?

Recent research has found that prairie dogs compete little for forage with cattle (~5%). In fact, by clipping grasses, prairie dogs eliminate old plant tissue and stimulate new plant growth. New plant growth contains more protein, so the nutritional quality of the vegetation on prairie dog colonies is greater than off colonies, despite the lower quantity of vegetation. Cattle have been found to gain similar to more weight when foraging on prairie dog colonies than off. Keep in mind that prairie dogs and bison have coexisted for millions of years, and bison and other ungulates consistently prefer to graze on prairie dog colonies.

What about falling into prairie dog holes?

The myth that cattle fall into prairie dog holes apparently began in the late 1800’s. During this time, cattle were over-stocked on rangeland here in the Southwest. Cattle were overgrazing the lands, and combined with a 25 year drought period at the end of the century, many of the grasslands became desertified. There was little forage for cattle to eat and many became sick and lethargic, causing some of the cattle to apparently fall into the burrows. A healthy cow slowly grazes with its head down and does not fall into burrows. Remember, bison evolved along with prairie dogs.

Some people like to ride their horses in the mountains but feel they can’t because prairie dog burrows are present. My advice is not to run your horse on a prairie dog colony, and find an alternative place to ride. These animals no longer occur in large colonies due to their population declines, and therefore, it should not be difficult to find an alternative place to ride. If we live in the mountains or are recreationally enjoying them it is important to remember that wildlife are present in these areas and we need to learn how to live with them, not eliminate them because they are in our way.

Prairie dogs as pets

Prairie dogs express social behavior that humans can relate to, but they do not make good pets. Because they are highly social animals, they should never be kept in isolation. Prairie dogs require considerable attention, and also are highly active with lots of energy and desire to chew and dig. They often will chew furniture when let out of their cage and will dig at rugs, tearing them up. In addition, prairie dogs have a breeding season each year, during which their hormones change and they can become aggressive. During this time even friendly prairie dogs can bite. Moreover, most prairie dogs sold as pets are taken directly from the wild. They have not been bred in captivity for generations, unlike most animals that we have for pets. Keep in mind that dogs have been domesticated for 10,000 years. Because prairie dogs have not been domesticated, they exhibit wild tendencies and may not always be friendly to the people they live with.

Wild prairie dogs sold for pets are often collected from areas where landowners want to reduce or eliminate the prairie dog population on their land. These prairie dogs have been acquired through unregulated harvest to provide profit for the pet trade. Some of the methods used to obtain prairie dogs for pets, such as removing prairie dogs with a “sucker truck,” a truck with a vacuum hose, are inhumane. The pet trade contributes to the decline of the species. If prairie dogs must be removed or controlled in an area, the animals should be humanely relocated to appropriate areas where their populations are desired.

Current efforts to protect prairie dogs within the state

Currently there are no efforts established to protect the Gunnison’s prairie dogs. However, both the city of Albuquerque and of Santa Fe do not allow the poisoning of this species within the city limits. The US Fish and Wildlife Service (USFWS) has determined that black-tailed prairie dogs have declined significantly throughout their range and that their status as a threatened species is “warranted but precluded.” Meaning that there are significant threats affecting the long-term viability of the black-tailed prairie dog, but there are insufficient resources to protect this species. The limited funds available to the USFWS for threatened and endangered species is currently being used for species that are of greater concern.

Game and fish departments from most states in which prairie dogs occur have established black-tailed prairie dog working groups. These working groups are designed to develop a management plan to reduce the decline of prairie dogs so that listing will not be necessary.

Why are they endangered? I see so many of them!

Often people think that because they see “lots” of prairie dogs that they couldn’t be declining. Keep in mind that they once occurred in huge numbers (~5 billion) throughout most of the grasslands in the central United States. They have declined greatly relative to their former abundance. There are many large threats affecting their populations: continued poisoning and shooting, habitat loss through development and desertification, and plague. In addition, many animal species that are dependent on the prairie dog require large colonies in order to support them. Most of the prairie dog colonies have become fragmented and isolated from one another, which lowers the long-term viability of maintaining the population and the other species dependent on them. The plight of the prairie dog is analogous to the passenger pigeon, once one of the most abundant and common species that has now become extinct due to human persecution.

How you can help

People are greatly needed to help in education, legislation, and relocation efforts. Contact a local wildlife organization such as Prairie Dog Pals or People for Native Ecosystems (contact info above) if you have an interest in helping the prairie dogs. You can also find more information about prairie dogs on the web at http://www.prairiedogs.org  and http://www.gprc.org  .

Ana D. Davidson, Ph.D.

Department of Biology

The University of New Mexico

Prairie Dog Talking Points

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  • Prairie dogs are a keystone species with up to 205 associated vertebrates (9 considered dependent) living with them, using their burrows, or predating upon them
  • There are 5 species of prairie dogs. The ones in Albuquerque are Gunnison’s, the others include Mexican, Utah, white and black tailed.
  • Gunnison’s prairie dogs hibernate during the winter months.
  • Over the last 100 years prairie dogs have been reduced to 1% of their former range and 2% of their population.
  • Some of the species are listed under the Endangered Species Act. Others are being considered for listing.
  • New Mexico has the smallest remaining acreage of prairie dogs.
  • Prairie dogs are territorial and will remain in or near their ancestral habitat if at all possible. The prairie dogs you see here in Albuquerque are the remnants of vast prairie dog towns that existed for hundreds of years.
  • Prairie dogs live an average of 3-5 years in the wild.
  • Prairie dogs are annual breeders. 50% of females over 2 years of age will breed and produce an average of 4 pups.
  • Pups are usually born in early May and will emerge from their burrows after about thirty days.
  • Prairie dogs have the most complex language of any animal ever studied.
  • They have over 200 words and can form sentences identifying intruders by color, size and type of risk.
  • Burrows are complex with a different area for each function of life. There are living chambers, sleeping and nesting rooms, a food storage area,
  • toilet rooms, and flood chambers. The burrows themselves generally include a second entrance or escape way, air chambers, and listening posts in addition to the main entrance.
  • As with humans, prairie dogs are the victims of plague. Virus carrying fleas are brought into the colony by wild animals or off leash cats or dogs.
  • As they have no immunity to the plague they will die within days.
  • Poisoning prairie dogs in both cruel and ineffective. The poison causes a slow agonizing death that may take up to three days.
  • A mature colony tends to expand at approximately 2% annually. A poisoned colony can expand at an annual rate of 70%. Additionally the poison can pose a danger to humans, cats, dogs, and other animals in the area.

Prairie Dogs and Plague

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PRAIRIE DOGS DO NOT TRANSMIT DISEASE TO HUMANS!

In the wild, prairie dogs are the victims of only one disease, plague. Plague was introduced to the west by settlers near the turn of the century and, “…we gave it to the prairie dogs”(1). It was first discovered in New Mexico in 1938(2). This non-native disease is spread by fleas and is carried into prairie dog towns by other animals such as mice, coyotes, and domestic dogs and cats. All mammals are capable of contracting plague. Once the fleas are present in a prairie dog colony, the entire town will perish within days, and individuals live for only a few hours.

Thus, if the plague is present, there are no active prairie dogs within about one week’s time. Such cases suggest that dogs infected with these diseases should be checked and admitted to a veterinary clinic as soon as possible. To prevent the spread of the plague, infected dogs can be euthanized humanely and compassionately if treatment is not possible. For more info on euthanization, visit this article.

Proven cases of human plague contracted from prairie dogs are virtually non-existent. The Centers for Disease Control and the department of health continually reinforce this fact. The CDC’s official position on destroying Prairie Dogs to control plague is, ” We do not recommend routine destruction of prairie dog colonies”(3). One CDC report specifically on plague says, “Plague in Cynomys Gunnisoni (Gunnison’s Prairie Dog) is devastating. Mortality during a plague epizootic typically exceeds 99%. Although mortality is great and flea infection rates may reach tremendous levels, human cases resulting from prairie dog plague are relatively few….and result from direct contact with an infected animal…Opisocrostis spp, (the fleas), maybe reluctant to bite humans”(4).

Cases of people contracting plague from live prairie dogs are non-existent. People who have been known to contract plague from prairie dogs can be traced to handling the corpse of an infected animal (5).

Some states have no record of anyone ever contracting disease from prairie dogs. The chances of contracting plague from a live prairie dog are so infinitesimally slim, it is simply a non-issue. Fleas will only seek a new host if the original host is deceased. For this reason, The Colorado Department of Health states, ...poisoning of burrowing rodents should not be routinely employed because this could release fleas into the environment and cause an increased risk to humans and pets” (6). Poisoning causes fleas to leave prairie dogs and other rodents in their burrows. This is the only time when a human health risk becomes a factor. Common sense points to the fact that having dozens of corpses present in an area is not a healthy environment for human activity. In contrast, everyone who regularly works with prairie dogs is vitally healthy. The writers of this plan have handled thousands of prairie dogs and they are all alive and well today. Nobody who regularly works with prairie dogs has ever suffered health complications of any kind. Though nearly impossible, if plague did strike in our times, plague is not synonymous with death. The disease can be treated with modern antibiotics and recovery rate is high, recovery time fairly brief.

Existing prairie dog colonies in Albuquerque neither have plague or would infect humans. One value of ‘city dogs’ is that if there is a large plague outbreak in an ecologically significant colony, these healthy animals can be reintroduced to prevent the collapse of the ecosystem. Plague can be controlled or prevented by using proper flea powder in prairie dog burrows once or twice per year (7). This practice is common in New Mexico and is generally conducted by the Department of Health or Environmental Divisions.

May we take this opportunity to reinforce the fact that prairie dogs are not able to become infected by or transmit any other disease including rabies or hanta virus. Plague is just another, tremendous threat against the survival of prairie dogs and their ecosystem. Gunnison’s prairie dogs, the variety in Albuquerque, are down to about 2% of their historical range (8) and are under consideration for listing under the Endangered Species Act (9).

Find out more about the dynamics of a plague outbreak here.

Literature Cited

1. Coniff, Richard 1998. Citing Pape, John. Epidiologist for Co Dept. of Health. Quoted on Wildlife Adventures, “Underdogs, Prairie Dogs Under Attack” Turner Productions, TBS

2. Cully, Jack. 1986 Metapopulation Characteristics of Sylvatic Plague Among Gunnison’s Prairie Dogs In the Moreno Valley, NM.(Citing Webber, 1978) Museum for Southwestern Biology, Department of Biology, University of New Mexico, Albuquerque, NM.

Cully, Jack F., Williams, Elizabeth S. 2001.Interspecific Comparisons of Sylvatic Plague in Prairie Dogs. Journal of Mammalogy. 82: 894-905

3. Reply letter to Prairie Ecosystems regarding official position of the CDC on prairie dogs and plague. Kathleen Orloski, DVM, MS, Epidemic Intelligence Service Officer. April 26, 1995.

4.. Centers for Disease Control Morbidity and Mortality Weekly Report. “Human Plague”, April 8, 2004, Vol. 43, No 13.

5.. Rocky Mountain News Spotlight article, “Dogs of War” quoting John Pape, Infectious Disease Specialist for The Colorado Dept. of Health. May 4, 1998.

6. Colorado Department of Health brochure, “Facts About Plague”, 1993.

7. Department of Health regular practice for controlling fleas. Rocky Mountain Arsenal National Wildlife Refuge and Plains Conservation Center have had tremendous success in controlling the spread of plague to reintroduced prairie dogs through this technique.

8. Knowles, C. 2001. Status of the Gunnison’s prairie dog. FWS & NWF.

9. Forest Guardians. 2004. Petition to List the Gunnison’s Prairie Dog as Threatened or Endangered Throughout its Range. Feb 23, 2004. www.fguardians.org

Prepared by: Prairie Ecosystems

 

Caregiver Protocols

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In 2008, Prairie Dog Pals submitted a proposal to the city for the rescue and relocation of prairie dogs. The RFP (Request for Proposals) contained some interesting language that gave us cause to review and update some of our procedures. The RFP required that we determine the necessary vaccinations for handling prairie dogs. While we were not aware of any requirements we researched CDC files and talked with our local health officials.

There are no vaccination requirements (please refer to the letter from the city regarding this.)

Based on the letter and our review of CDC recommendations for handling animals during rescue operations, we’ve developed our own protocol to protect our  volunteers.

Personal Protection for Caretakers

• Wash hands with soap and water:

  1. Before and after handling each animal
  2. After coming into contact with animal urine, feces, or blood
  3. After cleaning cages
  4. Before eating meals, taking breaks, smoking, or leaving the shelter
  5. Before and after using the restroom

• Use anti-bacterial cleanser after washing.

• Wear heavy protective gloves when handling prairie dogs.

• Wear surgical gloves when handling sick or wounded animals.

• Wear surgical and protective gloves when cleaning cages.

• Consider use of goggles or face protection if splashes from contaminated surfaces may occur.

• Do not allow rescued animals to bite or scratch you.

• Do not eat in animal care areas.

• Pregnant women and immuno-compromised persons should not volunteer for positions involving direct animal contact.

Optional

• Bring a change of clothes to wear home at the end of the day.

• Bag and thoroughly clean clothes worn at the shelter.

• Whenever possible, caretakers should have completed a 3-dose prophylactic vaccination series for rabies.

• Whenever possible, caretakers should have a tetanus shot to protect against infections from accidental scratches or bites.

Required

• In the event that a person is bitten by a prairie dog that appears to be ill or acting strangely, the animal will be surrendered for rabies testing and the person be given prophylactic vaccination as a precaution. In addition, the testing should include plague/tularemia screening in case the sick animal represents the first stage of a plague epizootic.