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Populational genetic structure of free-living maned wolves (Chrysocyon brachyurus) determined by proteic markers
De Mattos, P. S. R.;Del Lama, M. A.;Toppa, R. H.;Arno Rudi Schwantes, A. R.;
Brazilian Journal of Biology , 2004, DOI: 10.1590/S1519-69842004000400011
Abstract: electrophoretic analysis of presumptive twenty gene loci products was conducted in hemolisates and plasma samples of twenty-eight maned wolves (chrysocyon brachyurus) from an area in northeastern s?o paulo state, brazil. the area sampled was divided into three sub-areas, with the mogi-gua?u and pardo rivers regarded as barriers to the gene flow. the polymorphism degree and heterozygosity level (intralocus and average) estimated in this study were similar to those detected by other authors for maned wolves and other species of wild free-living canids. the samples of each sub-area and the total sample exhibited genotype frequencies consistent with the genetic equilibrium model. the values of the f-statistics evidenced absence of inbreeding and population subdivision and, consequently, low genetic distances were found among the samples of each area.
Comparison of two methods for glucocorticoid evaluation in maned wolves
Vasconcellos, Angélica S;Chelini, Marie-Odile M;Palme, Rupert;Guimar?es, Marcelo A.B.V;Oliveira, Cláudio A;Ades, César;
Pesquisa Veterinária Brasileira , 2011, DOI: 10.1590/S0100-736X2011001300013
Abstract: analysis of faecal glucocorticoid metabolites provides a powerful noninvasive tool for monitoring adrenocortical activity in wild animals. however, differences regarding the metabolism and excretion of these substances make a validation for each species and sex investigated obligatory. although maned wolves (chrysocyon brachyurus) are the biggest canids in south america, their behaviour and physiology are poorly known and they are at risk in the wild. two methods for measuring glucocorticoid metabolites in maned wolves were validated: a radio- and an enzyme immunoassay. an acth challenge was used to demonstrate that changes in adrenal function are reflected in faecal glucocorticoid metabolites. our results suggest that both methods enable a reliable assessment of stress hormones in maned wolves avoiding short-term rises in glucocorticoid concentrations due to handling and restraint. these methods can be used as a valuable tool in studies of stress and conservation in this wild species.
Population Dynamics of Wolves and Coyotes at Yellowstone National Park: Modeling Interference Competition with an Infectious Disease  [PDF]
Krystal Blanco,Kamal Barley,Anuj Mubayi
Quantitative Biology , 2014,
Abstract: Gray wolves were reintroduced to Yellowstone National Park (YNP) in 1995. The population initially flourished, but since 2003 the population has experience significant reductions due to factors that may include disease-induced mortality, illegal hunting, park control pro- grams, vehicle induced deaths and intra-species aggression. Despite facing similar conditions, and interference competition with the wolves, the coyote population at YNP has persisted. In this paper we introduce an epidemiological framework that incorporates natural, human-caused and disease-induced mortality as well as interference competition between two species of predators. The outcomes generated by this theoretical framework are used to explore the impact of competition and death-induced mechanisms on predators coexistence. It is the hope that these results on the competitive dynamics of carnivores in Yellowstone National Park will provide park management insights that result in policies that keep the reintroduction of wolves successful.
Effects of Wolves on Elk and Cattle Behaviors: Implications for Livestock Production and Wolf Conservation  [PDF]
Isabelle Laporte,Tyler B. Muhly,Justin A. Pitt,Mike Alexander,Marco Musiani
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0011954
Abstract: In many areas, livestock are grazed within wolf (Canis lupus) range. Predation and harassment of livestock by wolves creates conflict and is a significant challenge for wolf conservation. Wild prey, such as elk (Cervus elaphus), perform anti-predator behaviors. Artificial selection of cattle (Bos taurus) might have resulted in attenuation or absence of anti-predator responses, or in erratic and inconsistent responses. Regardless, such responses might have implications on stress and fitness.
Arctic Lineage-Canine Distemper Virus as a Cause of Death in Apennine Wolves (Canis lupus) in Italy  [PDF]
Daria Di Sabatino, Alessio Lorusso, Cristina E. Di Francesco, Leonardo Gentile, Vincenza Di Pirro, Anna Lucia Bellacicco, Armando Giovannini, Gabriella Di Francesco, Giuseppe Marruchella, Fulvio Marsilio, Giovanni Savini
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0082356
Abstract: Canine distemper virus (CDV) infection is a primary threat affecting a wide number of carnivore species, including wild animals. In January 2013, two carcasses of Apennine wolves (Canis lupus) were collected in Ortona dei Marsi (L'Aquila province, Italy) by the local Veterinary Services. CDV was immediately identified either by RT-PCR or immunohistochemistry in lung and central nervous tissue samples. At the same time, severe clinical signs consistent with CDV infection were identified and taped (Videos S1–S3) from three wolves rescued in the areas surrounding the National Parks of the Abruzzi region by the Veterinary Services. The samples collected from these symptomatic animals also turned out CDV positive by RT-PCR. So far, 30 carcasses of wolves were screened and CDV was detected in 20 of them. The sequencing of the haemagglutinin gene and subsequent phylogenetic analysis demonstrated that the identified virus belonged to the CDV Arctic lineage. Strains belonging to this lineage are known to circulate in Italy and in Eastern Europe amongst domestic dogs. To the best of our knowledge this is the first report of CDV Arctic lineage epidemics in the wild population in Europe.
The need for the management of wolves — an open letter
Arthur T. Bergerud
Rangifer , 2007,
Abstract: The Southern Mountain and Boreal Woodland Caribou are facing extinction from increased predation, predominantly wolves (Canis lupus) and coyotes (Canis latrans). These predators are increasing as moose (Alces alces) and deer (Odocoileus spp). expand their range north with climate change. Mitigation endeavors will not be sufficient; there are too many predators. The critical habitat for caribou is the low predation risk habitat they select at calving: It is not old growth forests and climax lichens. The southern boundary of caribou in North America is not based on the presence of lichens but on reduced mammalian diversity. Caribou are just as adaptable as other cervids in their use of broadleaf seed plant as forage. Without predator management these woodland caribou will go extinct in our life time.
Phylogeographic history of grey wolves in Europe
Ma?gorzata Pilot, Wojciech Branicki, W?odzimierz J?drzejewski, Jacek Goszczyński, Bogumi?a J?drzejewska, Ihor Dykyy, Maryna Shkvyrya, Elena Tsingarska
BMC Evolutionary Biology , 2010, DOI: 10.1186/1471-2148-10-104
Abstract: We found that haplotypes representing two haplogroups, 1 and 2, overlap geographically, but substantially differ in frequency between populations from south-western and eastern Europe. A comparison between haplotypes from Europe and other continents showed that both haplogroups are spread throughout Eurasia, while only haplogroup 1 occurs in contemporary North American wolves. All ancient wolf samples from western Europe that dated from between 44,000 and 1,200 years B.P. belonged to haplogroup 2, suggesting the long-term predominance of this haplogroup in this region. Moreover, a comparison of current and past frequencies and distributions of the two haplogroups in Europe suggested that haplogroup 2 became outnumbered by haplogroup 1 during the last several thousand years.Parallel haplogroup replacement, with haplogroup 2 being totally replaced by haplogroup 1, has been reported for North American grey wolves. Taking into account the similarity of diets reported for the late Pleistocene wolves from Europe and North America, the correspondence between these haplogroup frequency changes may suggest that they were associated with ecological changes occurring after the Last Glacial Maximum.Historical processes during the Pleistocene glaciations had a profound effect on intra-specific genetic differentiation [1-3]. In many extant species, distinct mitochondrial (mt) DNA lineages have non-overlapping geographic distribution, which may result from their isolation in different glacial refugia during the Last Glacial Maximum (LGM, 21,000 - 17,000 years B.P.) [4]. Genetic divergences between these mtDNA lineages are often dated to early Pleistocene or Pliocene [1-5], which may suggest their long-term geographic separation.However, recent studies based on mtDNA preserved in remains of Late Pleistocene mammals showed that an association between phylogenetic structure and geography does not necessarily imply long-term genetic isolation [6-9]. In cave hyenas Crocuta crocuta spel
Birth and mortality of maned wolves Chrysocyon brachyurus (Illiger, 1811) in captivity
MAIA, O. B.;GOUVEIA, A. M. G.;
Brazilian Journal of Biology , 2002, DOI: 10.1590/S1519-69842002000100004
Abstract: the aims of this study were to verify the distribution of births of captive maned wolves chrysocyon brachyurus and the causes of their deaths during the period from 1980 to 1998, based on the registry of births and deaths in the international studbook for maned wolves. to determine birth distribution and average litter size, 361 parturitions were analyzed for the 1989-98 period. to analyze causes of mortality, the animals were divided into four groups: 1. pups born in captivity that died prior to one year of age; 2. animals born in captivity that died at more than one year of age; 3. animals captured in the wild that died at any age; and 4. all animals that died during the 1980-98 period. in group 1, the main causes of mortality were parental incompetence (67%), infectious diseases, (9%) and digestive system disorders (5%). the average mortality rate for pups was 56%. parental incompetence was responsible for 95% of pup deaths during the first week of life. in group 2, the main causes were euthanasia (18%) and disorders of the genitourinary (10%) and digestive systems (8%). euthanasia was implemented due to senility, congenital disorders, degenerative diseases, and trauma. in group 3, the main causes were digestive system disorders (12%), infectious diseases (10%), and lesions or accidents (10%). the main causes of mortality of maned wolves in captivity (group 4) were parental incompetence (38%), infectious diseases (9%), and digestive system disorders (7%).
Birth and mortality of maned wolves Chrysocyon brachyurus (Illiger, 1811) in captivity  [cached]
MAIA O. B.,GOUVEIA A. M. G.
Brazilian Journal of Biology , 2002,
Abstract: The aims of this study were to verify the distribution of births of captive maned wolves Chrysocyon brachyurus and the causes of their deaths during the period from 1980 to 1998, based on the registry of births and deaths in the International Studbook for Maned Wolves. To determine birth distribution and average litter size, 361 parturitions were analyzed for the 1989-98 period. To analyze causes of mortality, the animals were divided into four groups: 1. pups born in captivity that died prior to one year of age; 2. animals born in captivity that died at more than one year of age; 3. animals captured in the wild that died at any age; and 4. all animals that died during the 1980-98 period. In group 1, the main causes of mortality were parental incompetence (67%), infectious diseases, (9%) and digestive system disorders (5%). The average mortality rate for pups was 56%. Parental incompetence was responsible for 95% of pup deaths during the first week of life. In group 2, the main causes were euthanasia (18%) and disorders of the genitourinary (10%) and digestive systems (8%). Euthanasia was implemented due to senility, congenital disorders, degenerative diseases, and trauma. In group 3, the main causes were digestive system disorders (12%), infectious diseases (10%), and lesions or accidents (10%). The main causes of mortality of maned wolves in captivity (group 4) were parental incompetence (38%), infectious diseases (9%), and digestive system disorders (7%).
Response of Wolves to Corridor Restoration and Human Use Management  [cached]
Brenda Shepherd,Jesse Whittington
Ecology and Society , 2006,
Abstract: Corridor restoration is increasingly being used to connect habitat in mountainous areas where rugged topography and increasing human activity fragment habitat. Wolves (Canis lupus) are a conservation priority because they avoid areas with high levels of human use and are ecologically important predators. We examined how corridor restoration through a golf course changes the distribution of wolves and their prey in Jasper National Park, Alberta, Canada. We followed and recorded wolf paths in the snow both within the corridor and in the surrounding landscape before and after a corridor was re-established. Track transects were used to estimate prey abundance and snow depths, and trail counters measured human activity. We compared resources on wolf paths to available movement routes using conditional logistic regression and also compared resources used by wolves before and after restoration. We addressed potential confounding effects of prey abundance, snow depths, and levels of human use by testing for changes in these variables. Prior to restoration, wolves traveled around the golf course and used the mountainside to connect valley-bottom habitat. Conversely, elk (Cervus elaphus) densities were highest in the golf course. After restoration, wolves shifted most of their movement to the golf course corridor, whereas elk dispersed along the corridor and mountainside. When traveling through the study area, wolves selected for areas with high prey abundance, low elevations, and low levels of human activity. Corridor restoration increased the area of high quality habitat available to wolves and increased their access to elk and deer at low elevations. Our results corroborate other studies suggesting that wolves and elk quickly adapt to landscape changes and that corridor restoration can improve habitat quality and reduce habitat fragmentation.
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