Adrian P. Wydeven

Causes and Implications of Species Restoration in Altered Ecosystems

gered Species Act of 1973 one year after passage. Since that time, natural recolonization and population recovery of wolves in the western Great Lakes region of the United States (the Lake States-Minnesota, Wisconsin, and Michigan) has been a notable success of the Act (Refsnider 1994). At the time of listing, the wolf was extirpated throughout the United States outside Alaska except for remnant populations in northeast Minnesota and on Isle Royale, in Lake Superior (Mech 1970). Since protection under the Act, the wolf population has in-

The Effects of Breeder Loss on Wolves

Abstract Managers of recovering wolf (Canis lupus) populations require knowledge regarding the potential impacts caused by the loss of territorial, breeding wolves when devising plans that aim to balance population goals with human concerns. Although ecologists have studied wolves extensively, we lack an understanding of this phenomenon as published records are sparse. Therefore, we pooled data (n = 134 cases) on 148 territorial breeding wolves (75 M and 73 F) from our research and published accounts to assess the impacts of breeder loss on wolf pup survival, reproduction, and territorial social groups. In 58 of 71 cases (84%), ≥1 pup survived, and the number or sex of remaining breeders (including multiple breeders) did not influence pup survival. Pups survived more frequently in groups of ≥6 wolves (90%) compared with smaller groups (68%). Auxiliary nonbreeders benefited pup survival, with pups surviving in 92% of cases where auxiliaries were present and 64% where they were absent. Logistic regression analysis indicated that the number of adult-sized wolves remaining after breeder loss, along with pup age, had the greatest influence on pup survival. Territorial wolves reproduced the following season in 47% of cases, and a greater proportion reproduced where one breeder had to be replaced (56%) versus cases where both breeders had to be replaced (9%). Group size was greater for wolves that reproduced the following season compared with those that did not reproduce. Large recolonizing (>75 wolves) and saturated wolf populations had similar times to breeder replacement and next reproduction, which was about half that for small recolonizing (≤75 wolves) populations. We found inverse relationships between recolonizing population size and time to breeder replacement (r = −0.37) and time to next reproduction (r = −0.36). Time to breeder replacement correlated strongly with time to next reproduction (r = 0.97). Wolf social groups dissolved and abandoned their territories subsequent to breeder loss in 38% of cases. Where groups dissolved, wolves reestablished territories in 53% of cases, and neighboring wolves usurped territories in an additional 21% of cases. Fewer groups dissolved where breeders remained (26%) versus cases where breeders were absent (85%). Group size after breeder loss was smaller where groups dissolved versus cases where groups did not dissolve. To minimize negative impacts, we recommend that managers of recolonizing wolf populations limit lethal control to solitary individuals or territorial pairs where possible, because selective removal of pack members can be difficult. When reproductive packs are to be managed, we recommend that managers only remove wolves from reproductive packs when pups are ≥6 months old and packs contain ≥6 members (including ≥3 ad-sized wolves). Ideally, such packs should be close to neighboring packs and occur within larger (≥75 wolves) recolonizing populations.

Forecasting Environmental Hazards and the Application of Risk Maps to Predator Attacks on Livestock

Environmental hazards are distributed in nonrandom patterns; therefore, many biologists work to predict future hazard locations from the locations of past incidents. Predictive spatial models, or risk maps, promise early warning and targeted prevention of nonnative species invasion, disease spread, or wildlife damage. The prevention of hazards safeguards both humans and native biodiversity, especially in the case of conflicts with top predators. Top predators play essential ecological roles and maintain biodiversity, but they can also threaten human life and livelihood, which leads people to eradicate predator populations. In the present article, we present a risk map for gray wolf (Canis lupus) attacks on livestock in Wisconsin between 1999 and 2006 that correctly identified risk in 88% of subsequent attack sites from 2007 to 2009. More-open habitats farther from any forest and closer to wolf pack ranges were the riskiest for livestock. Prediction promotes prevention. We recommend that the next generation of risk mappers employ several criteria for model selection, validate model predictions against data not used in model construction before publication, and integrate predictors from organismal biology alongside human and environmental predictors.

Ungulate Habitat Relationships in Wind Cave National Park

Etude du chevauchement des ressources alimentaires chez Cervus elaphus, Odocoileus hemionus, Antilocapra americana, Bison bison dans cette reserve du Dakota. Il existe une faible competition parmi ces especes, sauf pour B.b. et A.a.

History, Population Growth, and Management of Wolves in Wisconsin

While we were growing up in Wisconsin during the 1950s and 1960s, gray wolves (we always called them timber wolves, Canis lupus) were making their last stand in northern Wisconsin. Wolves were considered a wilderness-dependant relic of Wisconsin’s frontier past that no longer belonged in our state. We did not expect wolves to ever again return to the state, at least not in any sizeable numbers. Among us, Dick Thiel was the most tenacious about trying to find evidence of wolves in Wisconsin, even as a student in the 1960s and 1970s. When wolves began returning during the mid-1970s, we dared not hope for any more than a token population of wolves to reestablish. The recovery of wolves in Wisconsin has succeeded beyond our wildest dreams. We have had the pleasure to document and track the amazing return of this powerful predator to our state.

Recolonizing wolves trigger a trophic cascade in Wisconsin (USA)

Summary 1. We tested the hypothesis that wolves are reducing local browse intensity by white-tailed deer, thus indirectly mitigating the biotic impoverishment of understorey plant communities in northern Wisconsin. 2. To assess the potential for such a top-down trophic cascade response, we developed a spatially and temporally explicit model of wolf territory occupancy based on three decades of wolf monitoring data. Using a nested multiscale vegetation survey protocol, we compared the understorey plant communities of northern white cedar wetlands found in high wolf areas with control sites found in low wolf areas. 3. We fit species–area curves for plant species grouped by vegetation growth form (based on their predicted response to release from herbivory, i.e. tree, seedling, shrub, forb, grass, sedge or fern) and duration of wolf territory occupancy. 4. As predicted for a trophic cascade response, forb species richness at local scales (10 m 2 ) was significantly higher in high wolf areas (high wolf areas: 10.7 � 0.9, N = 16, low wolf areas: 7.5 � 0.9, N = 16, P < 0.001), as was shrub species richness (high wolf areas: 4.4 � 0.4, N = 16, low wolf areas: 3.2 � 0.5, N = 16, P < 0.001). Also as predicted, percentage cover of ferns was lower in high wolf areas (high wolf areas: 6.2 � 2.1, N = 16, low wolf areas: 11.6 � 5.3, N = 16, P < 0.05). 5. Beta richness was similar between high and low wolf areas, supporting earlier assumptions that deer herbivory impacts plant species richness primarily at local scales. Sampling at multiple spatial scales revealed that changes in species richness were not consistent across scales nor among vegetation growth forms: forbs showed a stronger response at finer scales (1–100 m 2 ), while shrubs showed a response across relatively broader scales (10–1000 m 2 ). 6. Synthesis. Our results are consistent with hypothesized trophic effects on understorey plant communities triggered by a keystone predator recovering from regional extinction. In addition, we identified the response variables and spatial scales appropriate for detecting such differences in plant species composition. This study represents the first published evidence of a trophic cascade triggered by wolf recovery in the Great Lakes region.

Experimental use of dog-training shock collars to deter depredation by gray wolves

Abstract We examined the use of dog shock collars on 2 different wolves (Canis lupus) over a 4-year period to assess whether this system could be used to reduce wolf depredation on livestock. In 1998 we used human-induced shock and determined that the shock collar could keep a depredating wolf off a farm while maintaining normal den- and rendezvous-site attendance, but it did not seem to have a long-term effect on the wolfs behavior. In 1999 we captured a wolf prior to any depredations and used a command center with a beeper that remotely shocked the wolf while also providing aversive stimuli; no depredations occurred in 1999. We used the beeper unit alone in 2000, when only 2 calves were killed. A second wolf was captured in 2001 after depredations began, and although it was kept off the farm, other pack members caused further depredation and were removed from the farm. It appears that in some situations shock collars with a command center and beeper device may be useful for reducing wolf depredations, but more research is needed.

Change in Occupied Wolf Habitat in the Northern Great Lakes Region

The concept of w olf habitat and relative suitability has changed significantly over the past several decades. In large part, this occurred because of insights gained during expansion of the wolf population in the northern Great Lakes states (Mech 1970 ; Erb and DonCarlos, this volume; Beyer et al., this volume; Wydeven et al., this volume). Protection from intentional killing of wolves since 1974, under the Endangered Species Act of 1973, began the process of wolf population growth and expansion in northeastern Minnesota, with eventual recolonization of northern Wisconsin and upper Michigan (Beyer et al., this volume; Wydeven et al., this volume). In 1955, W isconsin game manager John Keener wrote about wolves, “This animal is a symbol of the true wilderness. He cannot tolerate the advancing civilization of his wild home” (Keener 1955 : 22). As late as the 1980s it was still generally believed that wolves required wilderness to survive, though research was beginning to show otherwise (Mech et al. 1988 ; Mech 1989) . This concept lasted for so long in part because wolves had persisted only in the Boundary Waters Canoe Area Wilderness and adjacent areas of the Superior National Forest in northeastern Minnesota (Erb and DonCarlos, this volume), as well as Isle Royale National Park in Lake Superior (Vucetich and Peterson, this volume). Gradually, it became clearer that the role of wilderness was largely one of protection for wolves from killing through reduced human accessibility, rather than any innate requirements of wolves and their behavior (Mech 1995) . With protection, wolves colonized areas with greater human presence. At the same time, remoteness clearly has a positive effect on wolf survival because of reduced conflict with humans, reduced accidental killing of wolves (such as by vehicles), and perhaps less disease, as well as less intentional illegal killing. Remoteness provides one relative factor in defining degrees of habitat suitability for wolves. The other important factor is prey abundance. Ironically, in today’s human-dominated landscape, these factors are often in conflict. Human-dominated landscapes, both forests subject to harvesting and re-growth and agricultural lands, support high levels of prey (white-tailed deer,

Wolf–Human Conflicts and Management in Minnesota, Wisconsin, and Michigan

Recovery of gray wolves (Canis lupus) in the Great Lakes region has been accompanied by an increase in wolf—human conflicts. The interface between owners of domestic animals and wolf recovery presents unique challenges for wildlife management. Investigating wolf complaints, explaining wolf ecology, conservation goals, and litigation that has impacted wolf management to people who have had domestic animals killed by wolves are challenges faced by those involved with managing wolf—human conflicts. In this chapter, we describe wolf—human conflicts and management, focusing on the period 1974-2006, when wolves were protected under the Federal Endangered Species Act (ESA). The patterns of European settlement and wolf persecution were similar in Minnesota, Wisconsin. and Michigan. Minnesota maintained a bounty system for wolves from 1849 to 1965, aerial hunting of wolves persisted until 1956, from 1965 to 1973 wolves could be harvested for fur, and depredation control existed through a state program until May 1974, removing —250 wolves per year (Minnesota Department of Natural Resources [MNDNRI 2001; United States Fish Wildlife Service [USFWS] 2007). Wisconsin maintained a bounty system for predators, including wolves, from 1839 to 1957. A wolf bounty was the ninth law passed by the first Michigan legislature in 1838. By 1910, wolves were extirpated from Michigans Lower Peninsula. The bounty continued until 1922. From 1922 to 1935, a state trapper system was in effect. The bounty was reinstated in 1935 and repealed in 1960, after wolves were nearly extirpated from Michigan. In 1915, the United States Congress appropriated funds for a federal wolf control program administered by the United States Department of Agriculture. Bureau of Biological Survey (Young and Goldman 1944). Managers quickly recognized that public acceptance and effective depredation management were necessary for wolf recovery (USFWS 1978a, 1992; Peek et al. 1991). During recovery, depredation management was an important component of federal and state wolf management plans (USFWS 1992; Michigan Department of Natural Resources [MIDNR] 1997; Wisconsin Department of Natural Resources [WDNR] 1999, 2006; MNDNR 2001).

FOOD HABITS OF ELK IN THE NORTHERN GREAT PLAINS

Food habits of elk (Cervus elaphus nelsoni) were determined by 92 feeding-site examinations and examination of 30 rumen samples. Graminoids were the major forage class eaten in spring and summer. Forbs were the most important forage class in fall and winter, but moderate amounts of graminoids also were eaten. Elk seldom fed on browse throughout the year. Major plants eaten by elk included big bluestem (Andropogon gerardi), Louisiana sagewort (Artemisia ludoviciana), and threadleaf sedge (Carex filifolia). J. WILDL. MANAGE. 47(4):916-923 Food habits of elk have been exten- sively studied in the Rocky Mountain re- gion (Kufeld 1973), but few studies have been conducted on the Great Plains. Buechner (1950) conducted a 7-week study of elk food habits in Oklahoma, and Mackie (1970) analyzed elk food habits at the edge of the Great Plains in the Mis- souri Breaks of central Montana. We con- ducted a study of elk food habits in Wind Cave National Park (WCNP), South Da- kota, from July 1976 to August 1977 to determine elk feeding patterns through- out the year and to identify key forage species.