The natural history and ecology of melanism in red wolf and coyote populations of the southeastern United States – evidence for Gloger’s rule

Background: Gloger’s rule postulates that animals should be darker colored in warm and humid regions where dense vegetation and dark environments are common. Although rare in Canis populations, melanism in wolves is more common in North America than other regions globally and is believed to follow Gloger’s rule. In the temperate forests of the southeastern United States, historical records of red wolf (Canis rufus) and coyote (Canis latrans) populations document a consistent presence of melanism. Today, the melanistic phenotype is extinct in red wolves while occurring in coyotes and red wolf-coyote hybrids who occupy the red wolf’s historical range. To assess if Gloger’s rule could explain the occurrence and maintenance of melanistic phenotypes in Canis taxa, we investigated differences in morphology, habitat selection, and survival associated with pelage color using body measurements, GPS tracking data, and long-term capture-mark-recapture and radio-telemetry data collected on coyotes and hybrids across the southeastern United States. Results: We found no correlation between morphometrics and pelage color for Canis taxa. However, we observed that melanistic coyotes and hybrids experienced greater annual survival than did their gray conspecifics. Furthermore, we observed that melanistic coyotes maintained larger home ranges and exhibited greater selection for areas with dense canopy cover and wetlands than did gray coyotes. Conclusions: In the southeastern United States, pelage color influenced habitat selection by coyotes and annual survival of coyotes and hybrids providing evidence that Gloger’s rule is applicable to canids inhabiting regions with dense canopy cover and wetlands. Greater annual survival rates observed in melanistic Canis may be attributed to better concealment in areas with dense canopy cover such as coastal bottomland forests. We suggest that the larger home range sizes of melanistic coyotes may reflect the trade-off of reduced foraging efficiency in lower quality wetland habitat for improved survival. Larger home ranges and differential use of land cover by melanistic coyotes may facilitate weak assortative mating in eastern coyote populations, in which melanistic animals may have lower success of finding compatible mates in comparison to gray conspecifics. We offer that our observations provide a partial explanation for why melanism is relatively low (\u3c 10%) but consistent within coyote populations throughout southeastern parts of their range

Crossing Paths: Gray Wolves and Highways in the Minnesota-Wisconsin Border Region

Highways may threaten wolf (Canis lupus) habitat connectivity in the Great Lakes Region. Highways may further define the useable amount and arrangement of habitat within areas identified as suitable habitat. The two papers of this thesis explored wolf habitat with respect to roads by: (1) inferring wolf habitat connectivity across a major highway from predictions of crossing habitat, and (2) identifying how highways influenced suitable habitat choices and within-territory movements. Track searches, radio-telemetry, and observations identified 62 crossings of 4 major highways in northwestern Wisconsin between March 1991 and February 1999. Selected crossings (n=33) were visited to identify local crossing site characteristics. Compared to paired random sites wolves were equally likely to cross through forested and open landscapes (p = 0.192). In their immediate crossing environment, wolves favored factors related to visibility and ease of movement - less visual obscurity (p = 0.003) and less deciduous canopy cover (p = 0.038). Among the variables not significantly correlated with crossing sites were margin slope, maximum distance visible, shrub cover, and the presence/absence of trails or fences nearby. Satellite imagery data were used to map habitat composition and pattern within 25-400 ha of crossing sites. Patch density, an index to human-induced fragmentation, was the most significant and consistent indicator of crossing habitat across 5 landscape sampling resolutions (p < 0.005). Crossing landscapes had fewer patches, less open water, less developed land, and more forested or unforested wetlands than the available landscape matrix. Generally predictive ability increased with increased sampling area indicating that wolves perceived and reacted to landscape pattern at larger-spatial scales. Some differences between highways were noted, e.g., traffic volume and resident wolf activity in neighboring habitat, but the model captured elements of habitat selection specific to individual highways and common to all. Disperser and resident wolf crossings were equally represented by the model. Along U.S.H. 53 (a recently widened highway which bisects the primary wolf dispersal corridor in WI) the model mapped 68% of the road-adjacent habitat to have moderate-high crossing potential indicating a high degree of habitat connectivity. Highway crossing mitigations, e.g., widened medians and a highway underpass, were located where crossing potential was at least moderate. Only 20% (14 km) of the highway had high crossing potential of which 2 areas did not have any structural mitigations to aid crossings. The model was proved valid by 19 crossings reserved from analyses. Highway design may prove critical for continued connectivity as recreational and commercial use of the landscape increases in combination with increased traffic volume and vehicle speeds. Along the Minnesota-Wisconsin border, individual wolves from 4-12 wolf packs were radio-monitored between 1992-96. Resident wolf locations (n=3,448) were compared to unused locations (n=3,535)- outside of known wolf territories -with respect to the amount of major highways, minor highways, and non-highway public roads found within 200-ha of each location. Univariate logistic regression models indicated that highways did not strongly influence suitable habitat choices (less than 22% accuracy for unused habitats) but the density of non-highway public roads did (74% overall accuracy). Overall road density was still the best predictor of suitable habitat (77% overall accuracy). No improvement in classification accuracy was achieved by segregating highways from non-highway public roads. Males and pups demonstrated less tolerance for roads than females and older wolves (p < 0.001 ). All wolves combined demonstrated less tolerance for roads during the breeding and nomadic months (p < 0.001). These results indicated that not all habitats were equally available to wolves at all times - a critical consideration when estimating the total amount of useable wolf habitat in a given area. Sequential radio-locations (12-48 hours apart) were connected to investigate how often wolves crossed roads within their annual home ranges. Although highways were not a major factor in population-level habitat selection they strongly influenced within-territory movements (p < 0.001) which in tum affects the geographic arrangement of wolf territories in the landscape. All territories contained some nonhighway public roads, and wolves were either indifferent or attracted towards such roads. In contrast only one-half of the territories contained a major highway. Minor highways were strongly avoided in regular movements (p < 0.00 I). Potential highway tolerance limits for this population were identified as 0.09 km/km2 of major highways and 0.15 km/km2 of minor highways within territories. Considering the amount and arrangement of highways in the landscape could further help to define the subset of "suitable" wolf habitat (based on overall road densities) which is truly "useable" habitat to the population

Hierarchical, memory-based movement models for translocated elk (cervus canadensis)

The use of spatial memory is well-documented in many animal species and has been shown to be critical for the emergence of spatial learning. Adaptive behaviors based on learning can emerge thanks to an interdependence between the acquisition of information over time and movement decisions. The study of how spatio-ecological knowledge is constructed throughout the life of an individual has not been carried out in a quantitative and comprehensive way, hindered by the lack of knowledge of the information an animal already has of its environment at the time monitoring begins. Identifying how animals use memory to make beneficial decisions is fundamental to developing a general theory of animal movement and space use. Here we propose several mobility models based on memory and perform hierarchical Bayesian inference on 11-month trajectories of 21 elk after they were released in a completely new environment. Almost all the observed animals exhibited preferential returns to previously visited patches, such that memory and random exploration phases occurred. Memory decay was mild or negligible over the study period. The fact that individual elk rapidly become used to a relatively small number of patches was consistent with the hypothesis that they seek places with predictable resources and reduced mortality risks such as predation

Scales of movement by elk (Cervus elaphus) in response to heterogeneity in forage resources and predation risk

Animals may respond to spatial and temporal heterogeneity by altering their movement patterns. The time an animal spends in an area of a given size is termed 'first-passage time' and can be used to identify the scales at which different movement processes occur. Using first-passage time and 2-h observations, we identified nested spatial scales representing three movement behaviours for elk (Cervus elaphus) - inactive/resting (moves < 50 m), active/foraging (x̄ = 276.7 m, SD = 56.6), and active/relocating (x̄ = 1628.3 m, SD = 436.6). Our ability to identify inactive behaviour was limited by GPS accuracy. The scale separating relocating and foraging behaviour ranged 550-1650 m across individuals and varied quadratically with the mean patch size of cutover forest in an animal's home range. We classified path segments into the 3 movement behaviours and related behaviours to local environmental conditions. Elk were likely to be inactive in areas having a low predicted use by wolves (Canis lupus), farther than 50 m from anthropogenic linear clearings, and where microclimatic conditions were cool (high shrub cover and north to east-facing slopes). In contrast, elk were most likely to forage in areas having intermediate levels of herbaceous biomass and low movement costs. Elk were most likely to be relocating when in areas of high wolf use, when close to linear clearings, and in energetically costly situations such as moving upslope. We discuss how elk use of potential foraging habitats may be restricted in this landscape by risks imposed by predators, humans, or both

Value of protected areas to avian persistence across 20 years of climate and land-use change

Establishing protected areas, where human activities and land cover changes are restricted, is among the most widely used strategies for biodiversity conservation. This practice is based on the assumption that protected areas buffer species from processes that drive extinction. However, protected areas can maintain biodiversity in the face of climate change and subsequent shifts in distributions have been questioned. We evaluated the degree to which protected areas influenced colonization and extinction patterns of 97 avian species over 20 years in the northeastern United States. We fitted single-visit dynamic occupancy models to data from Breeding Bird Atlases to quantify the magnitude of the effect of drivers of local colonization and extinction (e.g., climate, land cover, and amount of protected area) in heterogeneous landscapes that varied in the amount of area under protection. Colonization and extinction probabilities improved as the amount of protected area increased, but these effects were conditional on landscape context and species characteristics. In this forest-dominated region, benefits of additional land protection were greatest when both forest cover in a grid square and amount of protected area in neighboring grid squares were low. Effects did not vary with species’ migratory habit or conservation status. Increasing the amounts of land protection benefitted the range margins species but not the core range species. The greatest improvements in colonization and extinction rates accrued for forest birds relative to open-habitat or generalist species. Overall, protected areas stemmed extinction more than they promoted colonization. Our results indicate that land protection remains a viable conservation strategy despite changing habitat and climate, as protected areas both reduce the risk of local extinction and facilitate movement into new areas. Our findings suggest conservation in the face of climate change favors creation of new protected areas over enlarging existing ones as the optimal strategy to reduce extinction and provide stepping stones for the greatest number of species

S4 Data -

(CSV)</p

Fig 4 -

A) Predicted white-tailed deer density (individuals/km2) for 1 km2 grids across the Adirondack Park, New York, USA, from a density surface model using distance sampling data via aerial surveys conducted during winter 2016. B) Map of the coefficients of variation for the selected model. High uncertainty occurs in areas where there was low sampling effort (Fig 1).</p

S2 Data -

(CSV)</p

Parameter estimates for the most parsimonious detection model for surveying white-tailed deer via helicopter during 2016 in Adirondack Park, New York.

Cover was a categorical variable and, when significant in a model, hardwood cover served as the reference category. Shown are β coefficients and standard error (SE).</p

Partial effects of statistically significant predictors on winter abundance of white-tailed deer in the Adirondack Park, New York during 2016 according to the best fitting generalized additive model (GAM).

A) Two‐dimensional plot of the bivariate geographic coordinates. The solid black lines represent the smooth functions. The locations of each 2.5-km2 survey segment are plotted as small dots. The dotted red and green lines represent −1 standard error and +1 standard error, respectively. The number on the lines indicate whether geographic coordinates had a positive effect (e.g., +1), a negative effect (e.g., −1), or were neutral (0) on deer abundance. B) Smooth function for the mean effect of the first principal component (PC1) (thermal cover and anthropogenic cover). The shaded area represents the 95% confidence intervals for the mean effect. The rug ticks at the bottom of the plot indicate the coverage of the range of values of each variable in the units surveyed. The number in parentheses on the y-axis indicate the effective degrees of freedom (a measure of flexibility) of each term.</p