Anich N.M.,501 Golf Course Road |
Worland M.,07 Sutliff Avenue |
Martin K.J.,801 Progress Road
Wilson Journal of Ornithology | Year: 2013
Spruce Grouse (Falcipennis canadensis) are listed as threatened in Wisconsin, and the boreal habitats in which they occur are likely to be threatened by changing climatic conditions. However, the limited information available on Spruce Grouse in the Upper Great Lakes region makes it unclear which habitat features are important for Spruce Grouse nesting in Wisconsin. We radiotracked 30 female Spruce Grouse in northern Wisconsin from 2007-2012 and located 25 nests. Eighteen of 25 nests were beneath black spruce (Picea mariana) trees. Only three nests were in upland, and only one in a stand of jack pines (Pinus banksiana), in contrast to studies from Michigan and Ontario. Overall concealment was a good predictor of nest sites for Spruce Grouse, but not a good predictor of nest survival. Nest survival was associated with moderately dense and uniform 0-0.5 m lateral vegetation cover. Seventeen of 25 nests were successful, with a daily survival rate of 0.985, overall productivity of 1.0 young/female, and 1.9 young/successful nest. Annual survival of adult males was estimated at 54%, adult females at 40%, and juvenile survival at 14% and 24% by two different methods. Estimates of λ of 0.65 and 0.67 suggest a declining population, but the upper confidence limit exceeds 1, not ruling out a stable or slightly increasing population. Protecting black spruce swamps will protect important nesting habitat for Spruce Grouse in Wisconsin. © 2013 by the Wilson Ornithological Society.
Anich N.M.,501 Golf Course Road |
Worland M.,07 Sutliff Avenue |
Martin K.J.,801 Progress Road
Wildlife Society Bulletin | Year: 2013
Spruce grouse (Falcipennis canadensis) habitat use varies widely across their range and is not well-understood near the southern extent of their range. Threats to conifers from climate change make understanding habitat use at the southern edge of the range increasingly important. We obtained habitat information on 55 radiocollared spruce grouse in northern Wisconsin, USA from 16 May 2007 to 10 July 2012. Black spruce (Picea mariana) and tamarack (Larix laricina) were the most common habitat components. Some of our findings differed from previous reports, including little use of eastern hemlock (Tsuga canadensis) or northern white cedar (Thuja occidentalis), use of tamarack in summer more than any other tree species, and winter roosting and feeding in red pine (Pinus resinosa), especially where jack pine (P. banksiana) was not available. Male display points contained fewer small broadleaf saplings (x = 652 trees/ ha), greater percent conifer (87%), more jack pine (x = 148 trees/ha), and denser canopy (x = 65% closure) compared with random points (3,288 small broadleaf saplings/ha, 70% conifer, 7 jack pine/ha, and 51% closure). Dense ground cover was the best predictor of brood points, although brood points were similar to random points. Winter flock points were typified by dense canopy cover (x = 76% closure) and more jack pine (x = 407/ha). Management should be focused on areas with extensive conifer, especially near black spruce-tamarack swamps. Retaining or establishing closed-canopy coniferous uplands, especially jack pine stands 15-30 years old, adjacent to lowland conifer swamps should benefit spruce grouse populations. © 2013 The Wildlife Society.
Anhalt C.M.,University of Wisconsin - Madison |
van Deelen T.R.,University of Wisconsin - Madison |
Schultz R.N.,770 Highway J |
Wydeven A.P.,501 Golf Course Road
Human-Wildlife Interactions | Year: 2014
Bioboundaries, also called biofences, are deterrents that attempt to exploit certain innate behaviors to exclude wildlife from target areas. We hypothesized that human-deployed scent marks and playbacks of foreign howls could simulate a territorial gray wolf (Canis lupus) pack impinging on a resident pack, thereby causing the resident pack to move. During summer 2010, we deployed a simulated-pack bioboundary near 3 wolf packs in northern Wisconsin and monitored their movements relative to 3 wolf packs experiencing a sham treatment, to control for effects of human presence. We analyzed wolves' locations (≥1 location per week) and used linear models with mixed effects to examine distance from the rendezvous site as a function of treatment (sham or experimental) and phase of treatment (before or after treatment was initiated), while accounting for variations in individual wolves. We found little evidence that biofences, as configured and deployed in this study, caused wolves to change use of their territory.
Everitts J.L.,Arkansas State University |
Benson T.J.,University of Illinois at Urbana - Champaign |
Bednarz J.C.,University of North Texas |
Anich N.M.,501 Golf Course Road
Wildlife Society Bulletin | Year: 2015
Prescribed fire is an often-used tool for managing or manipulating wildlife habitats. However, studies on the effects of prescribed fire on conservation-priority songbirds are limited. We examined effects of low-intensity prescribed burns on vegetation structure and composition, and on habitat use of 45 radiotagged male Swainson's warblers (Limnothlypis swainsonii) during the 2008 and 2009 breeding seasons in the St. Francis National Forest in eastern Arkansas, USA. We found that home ranges in areas with extensive burning (>50% burned) were significantly larger (x¯ = 14.4 ha, SE = 3.5, n = 13) than home ranges in areas with partial burning (<50% burned; x¯ = 6.1 ha, SE = 1.3, n = 5) and unburned home ranges (x¯ = 8.5 ha, SE = 1.1, n = 27). Burning decreased understory vegetation density, leaf-litter depth, and cover, but had no effect on density of woody stems, including giant cane (Arundinaria gigantean; a native bamboo that is thought to benefit from fire). Swainson's warblers did not completely avoid burned regions of their home ranges, but individuals selected dense understory habitats in burned and unburned areas, and burning appeared to intensify selection for areas with less-variable litter depth. Low-intensity burning appeared to have minimal impacts on Swainson's warbler habitat use, but did result in increased home-range size, possibly to compensate for burn-impacted habitat patches and to enable warblers to acquire adequate food resources. Based on our findings, we suggest that high-intensity fires or frequent burning could have significant negative impacts on Swainson's warbler habitat. Also, prescribed burning alone was not sufficient to restore remnant populations of cane or a dense understory. We suggest management involving canopy openings in combination with low-intensity fire may more likely promote the development of dense understory habitat, including giant cane preferred by Swainson's warblers and other understory-dependent birds. © 2015 The Wildlife Society. © The Wildlife Society, 2015.
Stenglein J.L.,University of Wisconsin - Madison |
Gilbert J.H.,Great Lakes Indian Fish and Wildlife Commission |
Wydeven A.P.,501 Golf Course Road |
Van Deelen T.R.,University of Wisconsin - Madison
Ecological Modelling | Year: 2015
Gray wolves (. Canis lupus) have complex life-histories due, in part, to mating systems that depend on intra-group dominance hierarchies set within an inter-group (pack) social structure linked to philopatric territories. In addition to this spatially oriented social structure, mortality risk associated with interactions with humans varies spatially. We developed an individual-based spatially explicit (IBSE) model for the southern Lake Superior wolf population to better capture the life-history of wolves in a harvest model. Simulated wolves underwent an annual cycle of life-history stage-dependent mate-finding, dispersal, reproduction, and aging on a simulated landscape reflecting spatially explicit state and water boundaries, Indian reservation boundaries and ceded territories, wolf harvest zones, livestock depredation areas, and a spatial mortality risk surface. The latter 3 surfaces were linked to mortality events for simulated wolves. We assessed our IBSE model and conducted a sensitivity analysis of the most uncertain parameters with a categorical calibration of patterns observed at the individual, pack, population, and landscape level. We found that without recreational harvest, the Wisconsin wolf population grew to an average carrying capacity of 1242 wolves after 50 years and breeding pairs persisted for a mean 1.8 years. We simulated 6 recreational harvest scenarios with varying rates and timings of harvest and assessed effects on population size, pack sizes, age ratios, dispersal and immigration rates, and breeding pair tenures of the Wisconsin wolf population. The simulated harvest with rates of 14% which corresponded to the 2012 harvest in Wisconsin reduced the populations 4% in the first year of harvest and equilibrated to the pre-harvest population size after 20 years of harvest, on average. A 30% harvest rate across the simulation on average reduced the populations by 65% after 20 years with some populations going extinct before 100 years. In general, harvest increased the proportion of pups in the simulated populations and decreased breeding pair tenure. Targeted lethal control was more effective than harvest for reducing the number of wolves near known livestock depredation sites. Our model facilitates prediction of important population patterns that is simultaneously dependent on complexities associated with spatially structured life history and mortality. © 2015 Elsevier B.V.