Bear baiting may put hunting dogs at risk from wolves

Bear hunters will tell you that a good way to attract a bear is to put out bait. And in 10 states, including Michigan and Wisconsin, that's perfectly legal. Hunting dogs are another useful technique in the bear-hunter's toolkit, and 17 states say that's just fine.

But who else likes bear bait? Gray wolves, that's who. And wolves that are feeling territorial about a bear bait stash can—and sometimes do—kill hunting dogs released at the bait site.

Like most interactions between wildlife and human beings, wolf attacks on hunting dogs illustrate a tangled trade-off: attracting bears for the hunters, attracting danger for their dogs.

Seeking possible ways to reduce potentially lethal encounters between wolves and bear hunting dogs, researchers at Michigan Technological University and the Michigan Department of Natural Resources compared bear hunting practices and regulations in Michigan and Wisconsin.

Joseph K. Bump, a Michigan Tech wildlife ecologist; Dean Beyer Jr. and Brian J. Roell from the Michigan DNR, and students Chelsea Murawski and Linda Kartano report their findings in the April 17, 2013 issue of the Public Library of Science (PLOS) journal PLOS ONE.

The researchers analyzed and compared a variety of factors in Michigan and Wisconsin, from regulations on bear baiting and compensation for hunting dog attacks to statistics such as the ratio of hunters to wolves and percentage of hunters using dogs to hunt bear.

They found that the neighboring states, with similar wolf and bear populations and similar numbers of bear-hunting permits issued per wolf, report dramatically different numbers of wolf attacks on hunting dogs. Wisconsin's relative risk of attack is two to seven times higher than Michigan's.

Bear baiting begins earlier in Wisconsin and lasts longer, the scientists note. "The longer you bait, the more opportunity you provide for wolves to discover and potentially defend bear-bait sites," says Bump. "Most hunters release their dogs at bait sites, and the longer the bait has been around, the more likely hunting dogs are to encounter territorial wolves who have found and are possibly defending the bait. So it appears that baiting is an important factor."

Wisconsin also compensates dog owners $2,500 per hunting dog killed by wolves. In fact, the Wisconsin DNR data show that compensation for wolf attacks on hounds costs the state more than it has spent for wolf attacks on any other category of domesticated animal, including calves, missing calves or cattle.

Michigan does not compensate dog owners for wolf attacks.

"Compensation can have multiple effects," Bump points out. " It is a reporting incentive, but it also creates an incentive for abuse. The net effect of compensation is far from clear, and it is an important factor to study further."

What can be done about wolves that prey on hunting dogs? One quick and obvious response appears to be to reduce the wolf population. In fact, the Wisconsin DNR has announced its intention to reduce the statewide population of wolves by half, from approximately 700 to approximately 350.

Bump and his co-authors recommend more conservation-friendly alternatives such as adjusting baiting regulations to start baiting later and allow it for a shorter time. "If a reduction in depredations is the goal, actions aside from (or in addition to) reducing wolf abundance might achieve that goal," they wrote in the PLOS ONE article.

"If stakeholders are serious about minimizing wolf depredations on bear-hunting dogs, then careful examination of the potentially exacerbating effects of bear baiting would appear to be a good idea," the wildlife ecologist suggests.

Black Bears: Here, Gone, and Back Again

A new study from the Wildlife Conservation Society (WCS) and the Nevada Department of Wildlife ( NDOW) has pieced together the last 150 years of history for one of the state’s most interesting denizens: the black bear.

The study, which looked at everything from historic newspaper articles to more recent scientific studies, indicates that black bears in Nevada were once distributed throughout the state but subsequently vanished in the early 1900s. Today, the bear population is increasing and rapidly reoccupying its former range due in part to the conservation and management efforts of NDOW and WCS.__Compelled in part by dramatic increases in human/bear conflicts and a 17-fold increase in bear mortalities due to collisions with vehicles reported between the early 1990s and mid- 2000s, WCS and NDOW began a 15-year study of black bears in Nevada that included a review of the animal’s little-known history in the state.

Over the course of the study, black bears were captured both in the wild and at the urban interface in response to conflict complaints. The captured animals used in the study (adult males and females only) were evaluated for multiple physiological indicators including condition, sex, reproductive status, weight, and age, prior to being released. From the information gathered, the population size in the study area was estimated to be 262 bears (171 males, 91 females).

Confirmed sightings and points of capture from 1988 to present were mapped and presented in the report to illustrate current population demographics, and will be used to inform bear management in Nevada.

“It’s critical to understand the population dynamics in a given area in order to make informed decisions regarding management,” said WCS Conservation Scientist Jon Beckmann. “This includes decisions on everything from setting harvest limits to habitat management to conservation planning in areas where people will accept occupation by bears. We used this long-term study to determine if reported incidences were due to an increasing or expanding bear population, or people moving to where bears are located. The answer is both.”

The study area extended from the Carson Range of the Sierra Nevada eastward to the Virginia Range and Pine Nut Mountains, and from Reno south to Topaz Lake—an area collectively referred to as the Carson front. Because many captures were in response to conflicts, the urban interfaces of cities and towns of the Lake Tahoe Basin were included.

Nevada’s Black Bear History Unraveled

In looking to integrate information on the historical demographics of black bears into their study, the authors found that little published scientific research or data was available and that the species’ history in Nevada went largely ignored until 1987— when complaints arising from sightings and road collisions with vehicles began.

Historical records compiled by retired NDOW biologist Robert McQuivey that included old newspaper articles, pioneer journals dating as far back as 1849, and NDOW records that had long been unavailable, were reviewed and confirmed that black bears were present throughout the state until about 1931. At that point, the authors concluded that “the paucity of historical references after 1931 suggest extirpation of black bears from Nevada’s interior mountain ranges by this time.”

“The historical records paint a very different picture of Nevada’s black bear than what we see today. This new perspective is a good indication of what bear management in this state could involve should the population continue to expand,” said the study’s lead-author Carl Lackey of NDOW.

The authors believe that while over-hunting and conflicts with domestic livestock contributed to the bear’s local extinction in the Great Basin, landscape changes due to clear-cutting of forests throughout western and central Nevada during the mining booms of the late 1800s played an important role as well. But as fossil fuels replaced timber as a heat and energy source, forestry and grazing practices evolved, and reforestation and habitat regeneration occurred in parts of the their former range, the bears rebounded.__Using the information gathered in their review of historic documents, the scientists mapped the distribution of black bears within the interior of Nevada during the 1800s and early 1900s. They recommend that historical range maps for the species in North America be revised to include the information produced as part of the study.__The study, Bear Historical Ranges: Expansion of an Extirpated Bear Population, appears in the current online edition of the Journal of Wildlife Management. Co-authors include Carl W. Lackey of the Nevada Department of Wildlife, Jon P. Beckmann of the Wildlife Conservation Society, and James Sedinger of the University of Nevada, Reno.

Carnivores, livestock and people manage to share same space study finds

In the southern Rift Valley of Kenya, the Maasai people, their livestock and a range of carnivores, including striped hyenas, spotted hyenas, lions and bat-eared foxes, are coexisting fairly happily according to a team of coupled human and natural systems researchers.

“I wouldn’t call the results surprising,” said Meredith Evans Wagner, a visiting scholar from the University of Florida in the Center for Systems Integration and Sustainability (CSIS) at Michigan State University and part of the research team. “Other research has shown that people and carnivores can coexist, but there is a large body of thought that believes carnivores need their own protected space to survive.”

The paper “Occupancy patterns and niche partitioning within a diverse carnivore community exposed to anthropogenic pressures” was recently published in Biological Conservation. Other authors are Paul Schuette and Scott Creel, of Montana State University, and Aaron Wagner, postdoctoral researcher in the BEACON Center for the Study of Evolution in Action at Michigan State.

The paper’s findings echo results of a study published in PNAS in September 2012 by Jianguo “Jack” Liu and Neil Carter of CSIS: namely that tigers and people are sharing the same space in Chitwan National Park in Nepal, albeit at different times.

Wagner and her colleagues spent just over two years documenting the carnivores of the southern Rift Valley, using motion-detecting camera traps to captures images of the creatures and people using four different areas of land: a conservation area with no human settlements, a grazing area that also had no human settlements, a permanent settlement area, and a buffer zone between the grazing and conservation areas that included seasonal human settlements.

While most of the results were expected – the majority of carnivore photos were taken after dark, most of the larger predators, such as lions and spotted hyenas, tended to be found in the conservation area that didn’t include any human settlements – there were some intriguing results.

“We found that while there were more striped hyenas in the conservation area, there were also striped hyenas in the buffer zone, close to the human settlement area,” Wagner explained. “The hyenas weren’t avoiding that area; they were using the settlement area as a resource in addition to hunting.”

When the Maasai slaughtered an animal for food, they throw the scraps out their back doors, which are at the edge of the buffer zone, where the striped hyenas were happy to eat them.

“Carnivores aren’t a problem for this group of Maasai,” Wagner said. “They’ve made a conscious decision to not hunt carnivores. If one of their livestock is killed by a carnivore, people don’t go out and kill a carnivore in retaliation. It’s a little bit unusual in that way. But in our study, we found that carnivores killing livestock didn’t happen a lot.”

“Wildlife is clearly driven away from the permanent settlement areas," said Aaron Wagner. "But the seasonal human migration out of the buffer zone keeps that area viable for wildlife. Numbers drop when the cattle and people move in, but the striped hyenas seem to have habits that allow them to compensate. They do scavenge around bomas [Maasai settlements] when the pickings are good, but they hunt, too. Even with the people around, there are enough prey left, or enough trickling in from the conservation area, that they have plenty to hunt. More often than not, when following a striped hyena that’s foraging (or playing at a den) at 3 a.m., there’s no indication that people are so close.”

Why Wolves are Forever Wild, But Dogs Can Be Tamed

Dogs and wolves are genetically so similar, it’s been difficult for biologists to understand why wolves remain fiercely wild, while dogs can gladly become “man’s best friend.” Now, doctoral research by evolutionary biologist Kathryn Lord at the University of Massachusetts Amherst suggests the different behaviors are related to the animals’ earliest sensory experiences and the critical period of socialization. Details appear in the current issue of Ethology.

Until now, little was known about sensory development in wolf pups, and assumptions were usually extrapolated from what is known for dogs, Lord explains. This would be reasonable, except scientists already know there are significant differences in early development between wolf and dog pups, chief among them timing of the ability to walk, she adds.

To address this knowledge gap, she studied responses of seven wolf pups and 43 dogs to both familiar and new smells, sounds and visual stimuli, tested them weekly, and found they did develop their senses at the same time. But her study also revealed new information about how the two subspecies of Canis lupus experience their environment during a four-week developmental window called the critical period of socialization, and the new facts may significantly change understanding of wolf and dog development.

When the socialization window is open, wolf and dog pups begin walking and exploring without fear and will retain familiarity throughout their lives with those things they contact. Domestic dogs can be introduced to humans, horses and even cats at this stage and be comfortable with them forever. But as the period progresses, fear increases and after the window closes, new sights, sounds and smells will elicit a fear response.

Through observations, Lord confirmed that both wolf pups and dogs develop the sense of smell at age two weeks, hearing at four weeks and vision by age six weeks on average. However, these two subspecies enter the critical period of socialization at different ages. Dogs begin the period at four weeks, while wolves begin at two weeks. Therefore, how each subspecies experiences the world during that all-important month is extremely different, and likely leads to different developmental paths, she says.

Lord reports for the first time that wolf pups are still blind and deaf when they begin to walk and explore their environment at age two weeks. “No one knew this about wolves, that when they begin exploring they’re blind and deaf and rely primarily on smell at this stage, so this is very exciting,” she notes.

She adds, “When wolf pups first start to hear, they are frightened of the new sounds initially, and when they first start to see they are also initially afraid of new visual stimuli. As each sense engages, wolf pups experience a new round of sensory shocks that dog puppies do not.”

Meanwhile, dog pups only begin to explore and walk after all three senses, smell, hearing and sight, are functioning. Overall, “It’s quite startling how different dogs and wolves are from each other at that early age, given how close they are genetically. A litter of dog puppies at two weeks are just basically little puddles, unable to get up or walk around. But wolf pups are exploring actively, walking strongly with good coordination and starting to be able to climb up little steps and hills.”

These significant, development-related differences in dog and wolf pups’ experiences put them on distinctly different trajectories in relation to the ability to form interspecies social attachments, notably with humans, Lord says. This new information has implications for managing wild and captive wolf populations, she says.

Her experiments analyzed the behavior of three groups of young animals: 11 wolves from three litters and 43 dogs total. Of the dogs, 33 border collies and German shepherds were raised by their mothers and a control group of 10 German shepherd pups were hand-raised, meaning a human was introduced soon after birth.

At the gene level, she adds, “the difference may not be in the gene itself, but in when the gene is turned on. The data help to explain why, if you want to socialize a dog with a human or a horse, all you need is 90 minutes to introduce them between the ages of four and eight weeks. After that, a dog will not be afraid of humans or whatever else you introduced. Of course, to build a real relationship takes more time. But with a wolf pup, achieving even close to the same fear reduction requires 24-hour contact starting before age three weeks, and even then you won’t get the same attachment or lack of fear.”

Italian wolves prefer pork to venison

Some European wolves have a distinct preference for wild boar over other prey, according to new research.

Scientists from Durham University, UK, in collaboration with the University of Sassari in Italy, found that the diet of wolves was consistently dominated by the consumption of wild boar which accounted for about two thirds of total prey biomass, with roe deer accounting for around a third.

The study analysed the remains of prey items in almost 2000 samples of wolf dung over a nine year period and revealed that an increase in roe deer in the wolf diet only occurred in years when boar densities were very low. In years of high roe deer densities, the wolves still preferred to catch wild boar.

The results are published in the journal PLOS ONE.

The research team related the prey remains in wolf dung to the availability of possible prey in part of Tuscany, Italy - an area recently colonised by wolves. The findings have implications for wildlife conservation as the impact of changing predator numbers on prey species is important for managing populations of both predators and prey.

Lead author, Miranda Davis, from the School of Biological and Biomedical Sciences at Durham University, said: "Our research demonstrates a consistent selection for wild boar among wolves in the study area, which could affect other prey species such as roe deer."

"Intriguingly, in other parts of Europe where red deer are also available, wolves appear to prefer this prey to wild boar, suggesting that they discriminate between different types of venison."

In Europe, the wolf (Canis lupis) is recovering from centuries of persecution and the expansion of wolf populations has the potential to change the ecology of communities of ungulates (hooved animals) by exposing them to natural predation by wolves, according to the researchers.

The preference for boar is in contrast to other areas of Europe where wolves often avoid boar as prey. One factor may be the relatively smaller size of Mediterranean boar, making them less dangerous to wolves in Mediterranean regions, compared to the larger-sized boar that roam other parts of Europe.

Co-author, Dr Stephen Willis, from the School of Biological and Biomedical Sciences at Durham University, said: "Wolves were hunted to extinction in the UK, probably by the end of the 17th century. Our findings from Italy suggest that if they were reintroduced into an area with a healthy ungulate population their impact on livestock could be minimal."

Tuscany's woodlands support populations of both roe deer and wild boar, and are also grazed by sheep, goats and cattle; however, wild boar and roe deer made up over 95 per cent of wolf diet in the study area, with very little evidence of livestock predation.

The scientists identified prey items from fragments of bones and hair in the wolf dung collected in the region. The prey categories included wild boar, roe deer, red deer, hare, small rodents, goats, sheep and cattle.

For more than five years of the study, the percentage of wolf diet made up of wild boar was more than twice that of roe deer. Other prey represented only a very small proportion of the diet.

The researchers believe that further dietary studies are essential for understanding the true impact of wolves on European wildlife over time.

Co-author, Dr Phil Stephens, from the School of Biological and Biomedical Sciences at Durham University added: "Wolves and brown bears are gradually returning to their former strongholds in Europe. Understanding the needs of these species, as well as their potential impacts, is going to be fundamental to managing that welcome return."

Elk bones tell stories of life, death, and habitat use at Yellowstone National Park

Josh Miller likes to call himself a conservation paleobiologist. The label makes sense when he explains how he uses bones as up-to-last-season information on contemporary animal populations.

Bones, he says, provide baseline ecological data on animals complementary to aerial counts, adding a historical component to live observation. In his November cover article for the Ecological Society of America's journal Ecology, he assesses elk habitat use in Yellowstone National Park by their bones and antlers, testing his method against several decades of the Park Service's meticulous observations.

Now an assistant research professor in the new Quaternary and Anthropocene Research Group in the Department of Geology at the University of Cincinnati, Miller located and recorded the elk bone data while a doctoral student in paleontology at the University of Chicago, and finished analyzing the data during a brief stint at the Florida Museum of Natural History at the University of Florida, in Gainesville. His work with modern animals grew out of curiosity about the fidelity of the fossil record in archiving animals and ecosystems of the distant past.

"It turns out that bones are really informative," he said. At Yellowstone, bone and antler concentrations mirror patterns of animal landscape use known from years of aerial surveys. "This opened up a completely unexpected opportunity for studying modern ecosystems, particularly for areas where our knowledge of animal populations is more limited."

Reconstructing animal community structure and habitat use through the bones of past generations is a new idea. Until recently, common knowledge held that, on the landscape, bones just don't last that long. But Miller has found that they can last for hundreds of years. Bones weather in a stereotypical pattern, from fresh to falling apart. He calibrated weathering in the Yellowstone bones through radiocarbon dating, gaining a familiarity that would allow him to pick up a bone and know it had seen a year, 20 years, or 80 to 100 years or more on the open ground.

Bull elk shed their antlers in late winter, when forage is sparse. Too poor in nutrients to interest most scavengers, heavy, and awkwardly shaped for displacement by the elements, antlers tend to stay where they fall. Miller found that, for the most part, the bones of calves don't travel far either, even in the mouths of predators. The bones of calves mark the range where their mothers sought plentiful food to fuel months of nursing, and shelter to hide their vulnerable newborns.

Old bones from past decades outline a range consistent with the living herd. Miller saw only moderate shifts in a few areas, even given the many recent changes at Yellowstone: the prodigious wildfires of 1988, repatriation of grey wolves starting in 1995, and regrowth of willows, aspen, and cottonwoods over the last couple of decades following a long decline during the 20th century.

Because bones can last decades to centuries in the Yellowstone environment, Miller says they can put relatively recent data from direct observation into broader context for managers looking at long-range planning, helping to sort out important changes from the noise of cyclical booms, busts and shifts in landscape use. Bones are a minimally invasive tool for tracking the history of range animals. They are data just lying on the ground, waiting to be collected.

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Spatial fidelity of skeletal remains: elk wintering and calving grounds revealed by bones on the Yellowstone landscape (2012) Joshua H. Miller. Ecology 93:11, 2474-2482.

Yellowstone wolf study reveals how to raise successful offspring

What are the key ingredients to raising successful, self-sufficient offspring? A new life sciences study using 14 years of data on gray wolves in Yellowstone National Park indicates that cooperative group behavior and a mother's weight are crucial. "A female's body weight is key in the survival of her offspring, and cooperation in the protection and feeding of young pups pays off in terms of the production of offspring," said Robert Wayne, a professor of ecology and evolutionary biology at UCLA and co-author of the new research, published this week in the online edition of the Journal of Animal Ecology. Wolves are social carnivores that live in territorial, kin-structured packs. Female wolves depend on other adults in the pack to help them provide food for their pups and defend the youngsters from predators — mainly, competing packs of wolves. The greater the group cooperation, the researchers say, the better the pack's survival advantage. "Consequently, larger packs tend to get larger and win the 'arms race' of holding territories against the aggressive actions of other packs," Wayne said. "Large packs get better at building armies of soldiers to defend their turf, and cooperative behavior and sociality are maintained by natural selection." Wolves were re-introduced into Yellowstone Park in the mid-1990s and are rapidly becoming one of the best-studied carnivore populations in the world; they are turning out to be an excellent model for the study of sociality and cooperation, Wayne said. Over many years of intensive collaborative study, former UCLA graduate student Dan Stahler (now a biologist with the National Park Service) and former UCLA postdoctoral scholar Bridgett vonHoldt (who worked in Wayne's laboratory and will soon become an assistant professor at Princeton University) analyzed genetic and life-history data on more than 300 gray wolves. They assessed survivorship and reproductive success, as well as the factors that influenced them, including body weight and pack size, among other variables. They found a striking association between pack size, body weight and offspring survival. "We discovered that mother wolves' body weight and pack size play a crucial role in enabling pups to survive and thrive from birth to young adulthood," said Utah State University assistant professor of wildlife resources Dan MacNulty, a co-author of the study. The research was funded by the National Science Foundation, the National Park Service and the Yellowstone Park Foundation, as well as private donors. Environmental conditions that impact wolf reproduction, the researchers say, include resource availability, population density and disease prevalence — especially deadly canine distemper, caused by a contagious virus to which pups are especially vulnerable. In addition to body weight and pack size, the researchers examined the effects of maternal age and color (gray or black coat) and wolf population size on reproductive success. "Each of these factors affects reproduction, but, overwhelmingly, female body weight and pack size are the main drivers of litter size and pup survival," said Stahler, the study's lead author. "Bigger females produce bigger litters; bigger packs are better equipped to hunt and defend pups and resources from competitors."