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In 1995, eight female pumas from Texas (Puma concolor stanleyana) were introduced into five areas in South Florida to remediate morphological and biomedical correlates of inbreeding depression that threatened the long-term survival of Florida panthers (P. c. coryi). Initial analysis of the results of this genetic introgression initiative has highlighted its success, including growth of the population, increased genetic heterozygosity, and reduced frequencies of physical traits associated with inbreeding, including cryptorchidism. However, panthers remain isolated from other puma populations and natural gene flow is not currently plausible. Using data collected from 65 panthers in the post-genetic introgression era (1998–2020), we assessed the benefits accrued to male panther reproductive parameters via this management initiative, the effect of genetic variables, and compared results to historic data. Microsatellite data were used to determine individual heterozygosity levels and qualify panther genetic ancestry as admixed (i.e., panthers descended from crosses with female Texas puma) or canonical (i.e., panthers that comprised most of the population prior to genetic introgression). A total of 47 admixed and 10 canonical panthers were identified; mean individual heterozygosity of canonical panthers (0.39) was significantly different from admixed panthers (0.63; t54= 4.7, P-value < 0.001). Admixed panthers exhibited higher mean values for total testicular volume, structurally normal spermatozoa, and total sperm in comparison to canonical panthers. The progressive improvement of sperm metrics demonstrates that the benefits of genetic introgression continue to have a positive impact on the population >25 years since the release of the Texas pumas. However, the Florida panther population remains small, isolated, and vulnerable to deterministic and stochastic events that warrants continued monitoring to assess when additional genetic introgression initiatives will need to be implemented in the future.

Movement patterns can influence an animal’s ability to secure food, find mates, and avoid enemies, potentially affecting individual fitness. We studied movement patterns of 10 male and 3 female endangered Florida panthers (Puma concolor coryi) using location data collected from a long-term (2005–2012) GPS collar study. Males traveled faster and covered longer daily distances than females during both the wet and dry seasons (wet:dry—males 289:372 m/h and 4,616:6,701 m; females 186:280 m/h and 2,629:5,239 m). Panthers occupying higher-selected habitat traveled faster, but with shorter daily movement distances in comparison to habitats that were less frequently selected. An index of risk (derived using traffic volume and road density) that was linked to habitat predicted to be avoided by panthers was associated with reduced daily movement distances. Our results suggest that Florida panthers alter their movement patterns in response to environmental change and anthropogenic disturbances.

The breeding population of the endangered Florida panther (Puma concolor coryi) is confined to the southern portion of the Florida peninsula. During the 20th century, a combination of isolation and small population size resulted in increased inbreeding. This ultimately led to a genetic restoration program in 1995 to alleviate correlates of inbreeding depression and avert extinction of the Florida panther. Genetic restoration involved the release of 8 female Texas pumas into the wild Florida population, a management initiative that has significantly improved the outlook for recovery. It is unknown whether genetic restoration changed the distinctive cranial morphology of the Florida panther; and whether some metrics that were historically used to differentiate Florida panthers from other subspecies of P. concolorare still valid. We used a high-resolution digital imaging system to compare cranial morphology from several groupings of Florida panthers that were defined by genetic restoration to elucidate any morphological changes this event may have had on cranial profile. Our results indicated that cranial measurements of Florida panthers were not significantly altered by genetic restoration.

Understanding the social dynamics of large carnivores is critical to effective conservation and management planning. We made the first attempt to delineate both paternity and relatedness for a population of cougar (Puma concolor) using microsatellite data. We analyzed a long-term genetic dataset collected from a hunted population in the Garnet Mountains of western Montana. We assigned paternity for 62.5% of litters sampled using both exclusion and likelihood analyses. Attempts at reconstructing unsampled paternal genotypes resulted in delineating possible sires for 8 more litters. Sires were on average younger than reported for males involved in pairings assessed via field data in other cougar populations. Although most mating pairs were unrelated, 5 of 17 pairings involved cougars with levels of relatedness corresponding to half-sibling and full-sibling or parent offspring relationship (r?=?0.215–0.575). Relatedness among adult and subadult males was higher than relatedness levels among adult and subadult females. Relatedness among males in the Garnet population differed from patterns hypothesized to occur under male-biased dispersal theories for cougars. The long-term impact of the turnover of resident cougars in hunted populations is still unclear and warrants additional research. Our results highlight the utility of monitoring cougar demographic parameters using a combination of genetic and field data that in turn may assist managers with determining cougar harvest quotas or strategies, harvest seasons, sustainable harvest, and the appropriate management level of cougar populations. © 2011 The Wildlife Society.

Abstract:Florida panthers (Puma concolor coryi) are listed as an endangered subspecies in the United States and they exist in a single Florida population with <100 individuals; all known reproduction occurs south of Lake Okeechobee. Habitat loss is the biggest threat to this small population and previous studies of habitat selection have relied on very high frequency (VHF) telemetry data collected almost exclusively during diurnal periods. We investigated habitat selection of 12 panthers in the northern portion of the breeding range using 1) Global Positioning System (GPS) telemetry data collected during nocturnal and diurnal periods and 2) VHF telemetry data collected only during diurnal periods. Analysis of both types of telemetry data yielded similar results as panthers selected upland (P< 0.001) and wetland (P< 0.001) forested habitat types. Our results indicated that forests are the habitats selected by panthers and generally support the current United States Fish and Wildlife Service panther habitat ranking system. We suggest that future studies with greater numbers of panthers should investigate panther habitat selection using GPS telemetry data collected throughout the range of the Florida panther and with location attempts scheduled more evenly across the diel period. Global Positioning System radiocollars were effective at obtaining previously unavailable nocturnal telemetry data on panthers; however, we recommend that panther researchers continue to collect VHF telemetry data until acquisition rates and durability of GPS collars improve. (JOURNAL OF WILDLIFE MANAGEMENT 72(3):633–639; 2008)

A comparison of the sampling effectiveness of a backpack electroshocker and small-mesh seine was conducted on the upper Cahaba River in the Valley and Ridge physiographic province of north-central Alabama. Each of 15 sites was sampled once during fall 1995 (20 September–23 October), spring 1996 (2 May–20 June), and fall 1996 (20 September–16 October). Sampling was conducted with both gears on the same day, and the same amount of sampling time was allocated to each gear. Samples were segregated into seven groups (Cyprinidae, Catostomidae, Percidae, Centrarchidae [further subdivided into sunfish-crappie and bass categories], and other families as a group), and comparisons of the percent relative abundance (PRA) of groups were made between gears at each sampling station. The PRAs of the groups differed significantly between gears at all 15 stations. Cyprinid PRAs were consistently higher in seine collections, whereas percids, sunfish-crappie, and bass PRAs were higher in electroshocker collections. The seine collected more cyprinid species, the electroshocker more centrarchid species. No difference between gears was observed in the species richness of percids and catostomids collected. The abundances of species collected by each gear were significantly correlated at only one site, indicating that the gears were capturing species in different proportions. Use of both sampling gears in this ecoregion produced more complete samples in terms of species richness and abundance than either gear would have produced on its own.

Natural recolonization by large carnivores has rarely been documented. American black bears (Ursus americanus) recently (1988-present) recolonized portions of their former range in western Texas. We used mtDNA sequence data (n = 144 bears) from 7 populations of southwestern black bears in New Mexico, Texas, and northern Mexico to test predictions regarding metapopulation structure of the species in this region and the source of recolonization in western Texas. Six variable nucleotides were detected, resulting in 5 mtDNA haplotypes. Although within-site diversity of haplotypes (h) and nucleotides (p) was low, a high degree of genetic partitioning among sites was detected (ϕST = 0.6301). Analyses pinpointed northern Mexico as the source of black bears for western Texas. Female-mediated gene flow is proceeding slowly in this system (Nfm = 0.4961 individuals/generation), but its occurrence was inferred via field observations. Nested clade analyses indicated that populations of bears in the Mexico–Texas region (area that encompasses mountain ranges within Nuevo Leon and Coahuila, Mexico, northward to smaller ranges located in the Trans-Pecos region of western Texas) were connected via restricted gene flow due to isolation by distance. Long-distance colonization is the likely cause of extant geographical associations between New Mexican and Mexico–Texas populations. The naturally fragmented, xeric environment of the Chihuahuan Desert impedes colonization, but is not a complete barrier to this process. Conservation initiatives concerning recolonization by black bears within the Mexico– Texas mainland–island metapopulation should focus on preventing human–bear interactions and maintaining corridors for dispersal between the mainland populations in Mexico and the island populations in western Texas.