Population Estimate for the Bluenose-East Caribou Herd Using Post-calving Photography

Genetic and spatial analyses suggest that what was previously described as the Bluenose herd of barren-ground caribou (Rangifer tarandus groenlandicus) comprises three separate populations. Of these, the Bluenose-East caribou herd (BECH) has received little coverage in past surveys. Existing estimates of abundance suggested that current harvest rates of Bluenose-East caribou (~5000 animals/year) might be excessive. We used post-calving photography in June-July 2000 to estimate the size of the BECH. A maximum of 33 radio-collared caribou were available for location in June 2000. We located 30 of these caribou and photographed distinct groups containing 23 collared individuals. Excluding caribou assumed to belong to the neighboring Bluenose-West herd, we photographed a minimum of 84 412 adult and 4193 calf caribou. Using a simple mark-recapture model to account for caribou associated with collared individuals not photographed, we calculated an estimate of 104 000 ± 22 100 (95% CI 84 412 - 126 100) non-calf caribou. A recently published stochastic model produced a considerably higher and more variable estimate of 208 700 (95% CI 112 600 - 474 700). In March 2001, we deployed seven more radio collars in anticipation of repeating the census in 2001, but poor weather conditions precluded the formation of large aggregations. Present densities of Bluenose-East caribou seem high, and we recommend regular monitoring of body condition to assess the potential for a forage-induced population crash.Des analyses génétiques et spatiales suggèrent que ce que l'on a décrit précédemment comme le troupeau de caribous des toundras Bluenose (Rangifer tarandus groenlandicus) est en fait composé de trois populations distinctes. De ces trois hardes, le troupeau de caribous Bluenose de l'Est (TCBE) n'a pas reçu beaucoup d'attention au cours des relevés antérieurs. Les estimations d'abondance qui existent ont suggéré que le taux de prélèvement actuel de ce caribou (~ 5000 animaux/an) pourrait être excessif. On a eu recours à des clichés pris immédiatement après la mise bas en juin-juillet 2000 pour évaluer la taille du TCBE. En juin 2000, un maximum de 33 caribous munis de colliers émetteurs étaient disponibles pour la localisation. On en a repéré 30 et on a photographié des groupes distincts contenant 23 individus équipés de colliers émetteurs. Si l'on exclut les caribous qui feraient partie de la harde voisine Bluenose de l'Ouest, on a photographié un minimum de 84 412 adultes et 4193 veaux. En utilisant un simple modèle de marquage-recapture pour tenir compte des caribous reliés aux individus munis de colliers émetteurs non photographiés, on en arrive à une estimation du nombre de caribous excluant les veaux de 104 000 ± 22 100 (intervalle de confiance de 95 %: 84 412 - 126 000). Un modèle probabiliste publié récemment a donné une estimation nettement plus élevée et plus variable de 208 700 (intervalle de confiance de 95 %: 112 600 - 474 700). En mars 2001, on a eu recours à sept colliers émetteurs supplémentaires en prévision d'une reprise du recensement en 2001, mais le mauvais temps a empêché la formation de grands regroupements. Les densités actuelles du caribou Bluenose de l'Est semblent élevées, et on recommande une surveillance continue de l'état corporel afin d'évaluer le potentiel d'un effondrement de la population dû à un manque de fourrage

Estimating the potential impact of canine distemper virus on the Amur tiger population (Panthera tigris altaica) in Russia

Lethal infections with canine distemper virus (CDV) have recently been diagnosed in Amur tigers (Panthera tigris altaica), but long-term implications for the population are unknown. This study evaluates the potential impact of CDV on a key tiger population in Sikhote-Alin Biosphere Zapovednik (SABZ), and assesses how CDV might influence the extinction potential of other tiger populations of varying sizes. An individual-based stochastic, SIRD (susceptible-infected-recovered/dead) model was used to simulate infection through predation of infected domestic dogs, and/or wild carnivores, and direct tiger-to-tiger transmission. CDV prevalence and effective contact based on published and observed data was used to define plausible low- and high-risk infection scenarios. CDV infection increased the 50-year extinction probability of tigers in SABZ by 6.3% to 55.8% compared to a control population, depending on risk scenario. The most significant factors influencing model outcome were virus prevalence in the reservoir population(s) and its effective contact rate with tigers. Adjustment of the mortality rate had a proportional impact, while inclusion of epizootic infection waves had negligible additional impact. Small populations were found to be disproportionately vulnerable to extinction through CDV infection. The 50-year extinction risk in populations consisting of 25 individuals was 1.65 times greater when CDV was present than that of control populations. The effects of density dependence do not protect an endangered population from the impacts of a multi-host pathogen, such as CDV, where they coexist with an abundant reservoir presenting a persistent threat. Awareness of CDV is a critical component of a successful tiger conservation management policy

Wildlife Trade and Human Health in Lao PDR: An Assessment of the Zoonotic Disease Risk in Markets.

Although the majority of emerging infectious diseases can be linked to wildlife sources, most pathogen spillover events to people could likely be avoided if transmission was better understood and practices adjusted to mitigate risk. Wildlife trade can facilitate zoonotic disease transmission and represents a threat to human health and economies in Asia, highlighted by the 2003 SARS coronavirus outbreak, where a Chinese wildlife market facilitated pathogen transmission. Additionally, wildlife trade poses a serious threat to biodiversity. Therefore, the combined impacts of Asian wildlife trade, sometimes termed bush meat trade, on public health and biodiversity need assessing. From 2010 to 2013, observational data were collected in Lao PDR from markets selling wildlife, including information on volume, form, species and price of wildlife; market biosafety and visitor origin. The potential for traded wildlife to host zoonotic diseases that pose a serious threat to human health was then evaluated at seven markets identified as having high volumes of trade. At the seven markets, during 21 observational surveys, 1,937 alive or fresh dead mammals (approximately 1,009 kg) were observed for sale, including mammals from 12 taxonomic families previously documented to be capable of hosting 36 zoonotic pathogens. In these seven markets, the combination of high wildlife volumes, high risk taxa for zoonoses and poor biosafety increases the potential for pathogen presence and transmission. To examine the potential conservation impact of trade in markets, we assessed the status of 33,752 animals observed during 375 visits to 93 markets, under the Lao PDR Wildlife and Aquatic Law. We observed 6,452 animals listed by Lao PDR as near extinct or threatened with extinction. The combined risks of wildlife trade in Lao PDR to human health and biodiversity highlight the need for a multi-sector approach to effectively protect public health, economic interests and biodiversity

Adenovirus and Herpesvirus Diversity in Free Ranging Great Apes in the Sangha Region of the Republic of Congo

Infectious diseases have caused die-offs in both free-ranging gorillas and chimpanzees. Understanding pathogen diversity and disease ecology is therefore critical for conserving these endangered animals. To determine viral diversity in free-ranging, non-habituated gorillas and chimpanzees in the Republic of Congo, genetic testing was performed on great-ape fecal samples collected near Odzala-Kokoua National Park. Samples were analyzed to determine ape species, identify individuals in the population, and to test for the presence of herpesviruses, adenoviruses, poxviruses, bocaviruses, flaviviruses, paramyxoviruses, coronaviruses, filoviruses, and simian immunodeficiency virus (SIV). We identified 19 DNA viruses representing two viral families, Herpesviridae and Adenoviridae, of which three herpesviruses had not been previously described. Co-detections of multiple herpesviruses and/or adenoviruses were present in both gorillas and chimpanzees. Cytomegalovirus (CMV) and lymphocryptovirus (LCV) were found primarily in the context of co-association with each other and adenoviruses. Using viral discovery curves for herpesviruses and adenoviruses, the total viral richness in the sample population of gorillas and chimpanzees was estimated to be a minimum of 23 viruses, corresponding to a detection rate of 83%. These findings represent the first description of DNA viral diversity in feces from free-ranging gorillas and chimpanzees in or near the Odzala-Kokoua National Park and form a basis for understanding the types of viruses circulating among great apes in this region

Using Mathematical Models In A Unified Approach To Predicting The Next Emerging Infectious Disease

Emerging infectious diseases (EIDs) pose a significant threat to human health, global economies, and conservation (Smolinski et al. 2003). They are defined as diseases that have recently increased in incidence (rate of the development of new cases during a given time period), are caused by pathogens that recently moved from one host population to another, have recently evolved, or have recently exhibited a change in pathogenesis (Morse 1993; Krause 1994). Some EIDs threaten global public health through pandemics with large-scale mortality (e.g., HN/AIDS). Others cause smaller outbreaks but have high case fatality ratios or lack effective therapies or vaccines (e.g. Ebola virus or methicillin-resistant Staphylococcus aureus). As a group, EIDs cause hundreds of thousands of deaths each year, and some outbreaks (e.g., SARS, H5N1) have cost the global economy tens of billions of dollars. Emerging diseases also affect plants, livestock, and wildlife and are recognized as a Significant threat to the conservation of biodiversity (Daszak et al. 2000). Approximately 60% of emerging human disease events are zoonotic, and over 75% of these diseases originate in wildlife (Jones et al. 2008). The global response to such epidemics is frequently reactive, and the effectiveness of conventional disease control operations is often too little, too late\u27: With rising globalization, the ease with which diseases spread globally has increased dramatically in recent times. Also, interactions between humans and wildlife have intensified through trade markets, agricultural intensification, logging and mining, and other forms of development that encroach into wild areas. Rapid human population growth, land use change, and change in global trade and travel require a shift toward a proactive, predictive, and preventive approaches for the next zoonotic pandemic