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Propagation programs contribute to the conservation of a species by preserving genetic and demographic stock that maybe used to reinforce or re-establish wild populations. Identifying traits that affect reproductive success is essential to achieve this goal. Longitudinal reproductive events of the captive population of endangered red wolves (Canis rufus Audubon and Bachman, 1851) were investigated to determine whether parental age, breeding experience, and rearing type were factors in reproduction, litter size, and sex ratio, as well as viability of offspring. Younger wolves were more likely to reproduce and produce larger litters than were older individuals. The age of the female, but not the male, had a negative effect on pup survival. Wolves that had prior experience in offspring production were more likely to reproduce again than were individuals that had no prior reproductive success, but prior sexual experience alone was not a factor in offspring production. Parental breeding experience had a negative effect on pup survival, but no apparent relationships with litter size or sex ratio. Declines in reproduction, fitness, and survival with advancing age suggest the effect is due to senescence, the onset of which occurs at 8 years of age in females. The results are consistent with the breeding-experience hypothesis. Key words: reproductive experience, breeding-experience hypothesis, senescence, age hypothesis, reproduction, red wolf, Canis rufus. Les programmes de propagation contribuent a la conservation des especes en preservant des stocks genetiques et demographiques pouvant etre utilises pour renforcer ou retablir les populations sauvages. L'identification des caracteres qui ont une incidence sur le succes de reproduction est essentielle a l'atteinte de cet objectif. Les evenements de reproduction longitudinaux de la population captive de loups roux (Canis rufus Audubon et Bachman, 1851) ont ete etudies dans le but de determiner si l'age des parents, leur experience en matiere de reproduction et le type d'elevage avaient une incidence sur le succes de reproduction, la taille et le rapport de masculinite de la portee, ainsi que la viabilite des louveteaux. Les jeunes loups etaient plus susceptibles de se reproduire et de produire de grandes portees que les loups plus ages. Il y avait une correlation negative entre l'age de la femelle, mais pas celui du male, et la survie des louveteaux. Les loups ayant deja produit une progeniture etaient plus susceptibles de se reproduire a l'avenir que les individus qui ne s'etaient pas encore reproduits avec succes, mais l'experience sexuelle seule n'avait pas d'incidence sur la production de petits. Il y avait une correlation negative entre l'experience parentale de reproduction et la survie des louveteaux, mais aucun lien apparent avec la taille ou le rapport de masculinite de la portee. Des baisses de la reproduction, de l'aptitude et de la survie avec l'age donnent a penser que cet effet est du a la senescence, qui commence a l'age de huit ans chez les femelles. Ces resultats sont compatibles avec l'hypothese de l'experience de reproduction. [Traduit par la Redaction] Mots-cles: experience de reproduction, hypothese de l'experience de reproduction, senescence, hypothese de l'age, reproduction, loup roux, Canis rufus., Introduction The red wolf (Canis rufus Audubon and Bachman, 1851) is a critically endangered canid (IUCN 2013) that was once widely distributed across the eastern and south-central United States (for [...]

ABSTRACT: Movement connects otherwise isolated populations, influencing demographic persistence and promoting gene flow. We evaluated the effect of movement on the genetic and demographic viability of the red wolf (Canis rufus) and tested the application of metapopulation theory to management of this endangered predator. The establishment of a captive subpopulation in the 1970s allowed persistence of the species and facilitated a reintroduction program that supported 2 wild subpopulations, one of which persists today. We assessed the effect of historical and potential future movement between the wild and captive subpopulations on the genetic and demographic viability of the metapopulation. We analyzed approximately 30 years of individual‐level data to quantify the effects of historical movement among subpopulations and constructed an individual‐based metapopulation model to predict the effects of future potential movement (i.e., releases of captive wolves) on the species’ persistence and genetic diversity. Counter to theory, increased movement has had positive demographic effects, with higher per capita movement rates leading to increased metapopulation growth and decreased subpopulation synchrony. These counter‐theoretical results are likely due to differences in reproduction and survival rates among subpopulations and the small size of the metapopulation. Furthermore, higher rates of movement did not increase retention of genetic diversity, likely because of the active pedigree‐based breeding management of the species already maximizing gene retention. Our model indicates that future releases of captive wolves are necessary, but not sufficient, for the survival of the species, and must be combined with changes to demographic rates in both the captive and northeastern North Carolina subpopulations. Our results highlight the need for models and field data that more adequately describe the viability of small metapopulations. © 2017 The Wildlife Society. [ABSTRACT FROM AUTHOR]

The taxonomic status of the red wolf (Canis rufus) is heavily debated, but could be clarified by examining historic specimens from the southeastern United States. We analyzed mitochondrial DNA (mtDNA) from 3 ancient (350-1900 year olds) putative wolf samples excavated from middens and sinkholes within the historic red wolf range. We detected 3 unique mtDNA haplotypes, which grouped with the coyote mtDNA clade, suggesting that the canids inhabiting southeastern North America prior to human colonization from Europe were either coyotes, which would vastly expand historic coyote distributions, an ancient coyote--wolf hybrid, or a North American evolved red wolf lineage related to coyotes. Should the red wolf prove to be a distinct species, our results support the idea of either an ancient hybrid origin for red wolves or a shared common ancestor between coyotes and red wolves. [ABSTRACT FROM AUTHOR]

Infectious diseases pose a significant threat to global biodiversity and may contribute to extinction. As such, establishing baseline disease prevalence in vulnerable species where disease could affect persistence is important to conservation. We assessed potential disease threats to endangered red wolves (Canis rufus) by evaluating regional (southeastern United States) disease occurrences in mammals and parasite prevalence in red wolves and sympatric coyotes (Canis latrans) in North Carolina. Common viral pathogens in the southeast region, such as canine distemper and canine parvovirus, and numerous widespread endoparasites could pose a threat to the red wolf population. The most prevalent parasites in red wolves and sympatric coyotes were heartworm (Dirofilaria immitis), hookworm (Ancylostoma caninum), and Ehrlichia spp.; several red wolves and coyotes were also positive for bacteria causing Lyme disease (Borrelia burgdorferi). Coyotes had a more species-rich parasite community than red wolves, suggesting they could harbor more parasites and act as a disease reservoir. Species identity and sex did not significantly affect parasite loads, but young canids were less likely to have heartworm and more likely to have high levels of endoparasites. Continued disease monitoring is important for red wolf recovery because low levels of genetic variability may compromise the wolves' abilities to combat novel pathogens from closely related species, such as domestic dogs and coyotes. [ABSTRACT FROM AUTHOR]

By the 1970s, government-supported eradication campaigns reduced red wolves to a remnant population of less than 100 individuals on the southern border of Texas and Louisiana. Restoration efforts in the region were deemed unpromising because of predator-control programs and hybridization with coyotes. The U.S. Fish and Wildlife Service (USFWS) removed the last remaining red wolves from the wild and placed them in a captive-breeding program. In 1980, the USFWS declared red wolves extinct in the wild. During 1987, the USFWS, through the Red Wolf Recovery Program, reintroduced red wolves into northeastern North Carolina. Although restoration efforts have established a population of approximately 70-80 red wolves in the wild, issues of hybridization with coyotes, inbreeding, and human-caused mortality continue to hamper red wolf recovery. We explore these three challenges and, within each challenge, we illustrate how research can be used to resolve problems associated with red wolf-coyote interactions, effects of inbreeding, and demographic responses to human-caused mortality. We hope this illustrates the utility of research to advance restoration of red wolves. [ABSTRACT FROM AUTHOR]