James R. Heffelfinger

Species‐wide phylogeography of North American mule deer (Odocoileus hemionus): cryptic glacial refugia and postglacial recolonization

Quaternary climatic oscillations greatly influenced the present‐day population genetic structure of animals and plants. For species with high dispersal and reproductive potential, phylogeographic patterns resulting from historical processes can be cryptic, overshadowed by contemporary processes. Here we report a study of the phylogeography of Odocoileus hemionus, a large, vagile ungulate common throughout western North America. We examined sequence variation of mitochondrial DNA (control region and cytochrome b) within and among 70 natural populations across the entire range of the species. Among the 1766 individual animals surveyed, we recovered 496 haplotypes. Although fine‐scale phylogenetic structure was weakly resolved using phylogenetic methods, network analysis clearly revealed the presence of 12 distinct haplogroups. The spatial distribution of haplogroups showed a strong genetic discontinuity between the two morphological types of O. hemionus, mule deer and black‐tailed deer, east and west of the Cascade Mountains in the Pacific Northwest. Within the mule deer lineage, we identified several haplogroups that expanded before or during the Last Glacial Maximum, suggesting that mule deer persisted in multiple refugia south of the ice sheets. Patterns of genetic diversity within the black‐tailed deer lineage suggest a single refugium along the Pacific Northwest coast, and refute the hypothesis that black‐tailed deer persisted in one or more northern refugia. Our data suggest that black‐tailed deer recolonized areas in accordance with the pattern of glacial retreat, with initial recolonization northward along a coastal route and secondary recolonization inland.

Influence of precipitation timing and summer temperatures on reproduction of Gambel's quail

We analyzed the influence of rainfall and temperature patterns on Gambels quail (Callipepla gambelii) to better understand variability in call counts and reproduction. Based on data collected in Arizona during 1978-96, midwinter (Dec-Jan) precipitation invoked a stronger calling response than early-winter (Oct-Nov) or late-winter (Feb-Mar) rainfall Reproductive failure (< I juv/ad) was associated with low rainfall in October-March and high mean daily temperatures during June-July. Moderate production (1-2 juv/ad) occurred under low rainfall in winter, if June-July temperatures were cool. For any rainfall pattern, higher temperatures in July were associated with lower age ratios.

The role of hunting in North American wildlife conservation

Regulated hunting is the foundation of the North American Model of Wildlife Conservation. This conservation paradigm arose out of a movement, lead by prominent hunters, to stop over-exploitation of wildlife by market hunters and the desire to have wildlife accessible to all people. Since then, hunters have contributed billions of dollars to wildlife management that benefit countless wildlife species. These funds support wildlife management agencies which manage all wildlife species, not just those that are hunted. This unique and successful conservation paradigm is responsible for supporting a wide variety of conservation activities, including law enforcement, research, information and education, habitat management and acquisition, as well as wildlife population restoration and management. Although wildlife conservation activities embrace far more than the hunted species, hunters continue to be the primary agents of financial support, management assistance and organized advocacy.

Hybrid swarm between divergent lineages of mule deer (Odocoileus hemionus)

Studies of hybrid zones have revealed an array of evolutionary outcomes, yet the underlying structure is typically characterized as one of three types: a hybrid zone, a hybrid swarm or a hybrid taxon. Our primary objective was to determine which of these three structures best characterizes a zone of hybridization between two divergent lineages of mule deer (Odocoileus hemionus), mule deer and black‐tailed deer. These lineages are morphologically, ecologically and genetically distinct, yet hybridize readily along a zone of secondary contact between the east and west slopes of the Cascade Mountains (Washington and Oregon, USA). Using microsatellite and mitochondrial DNA, we found clear evidence for extensive hybridization and introgression between lineages, with varying degrees of admixture across the zone of contact. The pattern of hybridization in this region closely resembles a hybrid swarm; based on data from 10 microsatellite loci, we detected hybrids that extend well beyond the F1 generation, did not detect linkage disequilibrium at the centre of the zone and found that genotypes were associated randomly within the zone of contact. Introgression was characterized as bidirectional and symmetric, which is surprising given that the zone of contact occurs along a sharp ecotone and that lineages are characterized by large differences in body size (a key component of mating success). Regardless of the underlying mechanisms promoting hybrid swarm maintenance, it is clear that the persistence of a hybrid swarm presents unique challenges for management in this region.

Infectious Keratoconjunctivitis in Bighorn Sheep, Silver Bell Mountains, Arizona, USA

An infectious keratoconjunctivitis (IKC) epizootic in bighorn sheep (Ovis canadensis) occurred in the Silver Bell Mountains, Arizona, USA, from 1 December 2003 to 31 March 2004. We used standard culture methods and polymerase chain reaction (PCR) amplification of the 16S rRNA gene to test for the causative agents of IKC and other diseases reported to be associated with bighorn sheep populations. All bighorn sheep and domestic goat test results were negative except for Mycoplasma spp. and Branhamella spp. The culture and PCR results differed. Conjunctival swabs from four of 19 IKC-affected bighorn sheep tested by culture were positive for Mycoplasma spp., whereas 22 of 22 bighorn sheep samples tested by PCR were positive for Mycoplasma spp. None of 13 domestic goats tested positive by culture for Mycoplasma spp., whereas five of 16 tested positive by PCR. Three of 16 domestic goats and seven of 24 IKC-affected bighorn sheep tested positive for Branhamella spp. by culture. Bighorn sheep began showing clinical signs of IKC between 21 and 28 days following initial detection of domestic goats in bighorn sheep habitat. The IKC epizootic lasted 122 days, and individual bighorn sheep were blind for an average of 38.4 days. Given the clear potential for disease transmission to bighorn sheep, we recommend that land managers not allow the pasturing of domestic goats near occupied bighorn sheep habitat.

Range-wide analysis of genetic structure in a widespread, highly mobile species (Odocoileus hemionus) reveals the importance of historical biogeography

Highly mobile species that thrive in a wide range of habitats are expected to show little genetic differentiation across their range. A limited but growing number of studies have revealed that patterns of broad‐scale genetic differentiation can and do emerge in vagile, continuously distributed species. However, these patterns are complex and often shaped by both historical and ecological factors. Comprehensive surveys of genetic variation at a broad scale and at high resolution are useful for detecting cryptic spatial genetic structure and for investigating the relative roles of historical and ecological processes in structuring widespread, highly mobile species. In this study, we analysed 10 microsatellite loci from over 1900 samples collected across the full range of mule deer (Odocoileus hemionus), one of the most widely distributed and abundant of all large mammal species in North America. Through both individual‐ and population‐based analyses, we found evidence for three main genetic lineages, one corresponding to the ‘mule deer’ morphological type and two to the ‘black‐tailed deer’ type. Historical biogeographic events likely are the primary drivers of genetic divergence in this species; boundaries of the three lineages correspond well with predictions based on Pleistocene glacial cycles, and substructure within each lineage demonstrates island vicariance. However, across large geographic areas, including the entire mule deer lineage, we found that genetic variation fit an isolation‐by‐distance pattern rather than discrete clusters. A lack of genetic structure across wide geographic areas of the continental west indicates that ecological processes have not resulted in restrictions to gene flow sufficient for spatial genetic structure to emerge. Our results have important implications for our understanding of evolutionary mechanisms of divergence, as well as for taxonomy, conservation and management.

Serologic Survey for Antibodies to Canine Distemper Virus in Collared Peccary (Tayassu tajacu) Populations in Arizona

In 1989, a disease outbreak was observed among collared peccaries (javelina, Tayassu tajacu) in southern Arizona (USA) and canine distemper virus (CDV) was isolated from affected animals. Subsequently, 364 sera were collected from hunter-harvested javelina over a 4 yr period (1993–96) and were tested for antibody to CDV. Neutralizing antibody to CDV was detected in 58% of the serum samples suggesting that CDV infection is probably enzootic in the collared peccary populations of southern Arizona.

POPULATION GENETIC ANALYSIS OF SONORAN PRONGHORN (ANTILOCAPRA AMERICANA SONORIENSIS)

Abstract The endangered Sonoran pronghorn (Antilocapra americana sonoriensis) consists of only 2 small populations, 1 in Arizona and 1 in Mexico. Mitochondrial DNA sequence data and 5 microsatellite loci were used to compare levels of genetic diversity and differentiation between the 2 Sonoran pronghorn populations and between this subspecies and other selected pronghorn populations, both proximate and distant to the Sonoran pronghorns current range. The data support a history of recent isolation of Sonoran pronghorn populations from those in Arizona, New Mexico, and Texas. Loss of genetic diversity due to bottlenecks and drift has been severe in both populations of the Sonoran pronghorn, but is most pronounced in the Arizona population. These results are discussed in terms of conservation management strategies.

INFLUENCE OF MINING ON BEHAVIOR OF BIGHORN SHEEP

Abstract Mining has been cited as detrimental to bighorn sheep (Ovis canadensis), but little research exists that has demonstrated those effects. We compared behavior of bighorn sheep while individuals were inside and outside of an active copper mine to determine if individual animals were altering their behavior relative to the active mine. We conducted this study in the Silver Bell Mountains, Arizona, from December 2003 to January 2005. We observed 3 radiocollared subadult males, 4 adult males, and 5 females, and recorded behavior throughout the daylight period. After accounting for differences by sex-age class (i.e., subadult male, adult male, female) and season (i.e., breeding, non-breeding), bighorn sheep fed less (6%) while inside the mine perimeter. Other behaviors (e.g., bedding, standing, alert, and interacting) were observed for similar amounts of time while within and outside the mine perimeter. Within sex-age classes, there were few differences in behavior. Subadult males fed less (mean difference  =  −18.6%, 95% C.I.  =  −43.1–6.0) and bedded more (mean difference  =  14.3%, 95% C.I.  =  −40.9–69.4) while inside the mine. During the breeding season, adult males were alert less and interacted less (alert, mean difference  =  4.1%, 95% C.I.  =  −1.63–9.9; interacting, mean difference  =  3.1%, 95% C.I.  =  −5.7–11.9) while inside the mine. Females interacted more (mean difference  =  0.37%; 95% C.I.  =  −0.01–0.8) while inside the mine area. Elements of modern mining activity (e.g., vehicular traffic, humans afoot near vehicles, sounds) might be predictable to bighorn sheep allowing them to habituate to those human activities.

Bighorn Sheep Selection of Landscape Features in an Active Copper Mine

Abstract Bighorn sheep (Ovis canadensis) and Dalls sheep (O. dalli) use mining areas despite high human activity. We studied bighorn sheep selection of landscape features within a mine in a desert environment to determine those important for bighorn sheep and to enhance reclamation efforts of mines in desert environments. We collared and observed 8 male and 6 female bighorn sheep from December 2003 to January 2005 in the Silver Bell Mountains, Arizona, USA. We classified 13 unique features within a mine landscape based on topography, hydrology, and vegetation. Subadult male, adult male, and female bighorn sheep used desert islands (54, 76, and 54%, respectively) followed by highwalls (14, <10, and 11%, respectively). Subadult male, adult male, and female bighorn sheep selected for desert islands, and subadult males and females also selected for highwalls, whereas adult males did not. We did not observe bighorn sheep using leach ponds, pit bottoms, or tailings dumps. Bighorn sheep behavior while on desert islands was similar to behavior recorded when outside the mine perimeter. Subadult male and female bighorn sheep fed and were alert less and socially interacted more on highwalls than they did while outside the mine perimeter. Bighorn sheep in mines select areas similar to conspecifics outside of mined areas. In areas where mining and bighorn sheep are in proximity, mining engineers and wildlife biologists should work together to design reclamation plans that benefit bighorn sheep. In places where revegetation is difficult (i.e., deserts), mine engineers should design infrastructure (i.e., roadways, waste dumps, buildings) to minimize the unnecessary destruction of native slopes and vegetation.