By Heath Martin
Predators have become a popular topic as of late in North America. It seems just about any big game species that you can hunt is being affected in some way by predators. Everyone in the West is well aware of the reintroduction of the wolf and the havoc it is wreaking in certain areas on elk and moose populations. Mountain lion populations are on the rise and affecting sheep populations in some areas as well as mule deer. It is well known that coyotes have now spread east all across America and many studies have shown coyotes have a predatory effect on not only neonatal white-tail deer, but also a percentage of the adult population as well. These are all predators that when discussed don’t get much argument as to their predatory status. However, when it comes to bears, there seems to be a disconnect from predatory status for some reason in many debates, at least with certain subspecies of bears, that is.
With out question, polar bears (Ursus maritimus) are unequivocally predators. Their main source of food throughout most of the year, when they can travel on the see ice, is seal. Bearded seal and ringed seal are the most common prey, but depending on the region of the Arctic, they will also hunt harp seals and can be successful hunting beluga whales. They will also scavenge the carcass of a walrus, bowhead whale or grey whale if the opportunity arises. During the summer months they will eat just about any available animals, berries, shellfish or rodents. Their predatory status is not questioned.
Brown bears, coastal brown (Ursus arctos gyas), Kodiak (Ursus arctos middendorffi), thought to be the same subspecies by many biologists, grizzly (Ursus arctos horribilis), and black bears (Ursus americanus) on the other hand don’t always have the same status quo for being apex predators on big game species.
There is no argument that coastal brown, Kodiak, and coastal black bears are ferocious carnivores during the salmon spawning season. Magazines, Outdoor Channel, Discovery Channel and National Geographic, just to name a few, are famous for breath taking pictures, aerial videography scenes and world-class documentaries of all these species fishing for salmon in the pristine raging tributaries of the wilds of coastal North America. They gorge themselves daily on this high protein food that is so abundantly available during portions of the year. This is the main reason that these species along this coastal plethora of food are larger than their inland cousins. The inland grizzly and black bears don’t typically get as large; their diet consists with more of an omnivorous variety of foods throughout the entire year. Berries, forbs, legumes, small rodents, small mammals, roots, hard mast, insects, and scavenging the rare elk, deer or moose carcass is thought to be the main stay of their yearly caloric intake. Therefore when you talk to many people about bears being predators, this is about the extent of it, they eat fish and small animals. The allure of being an efficient big game predator just doesn’t follow them into many debates or discussions.
There are many studies over the past forty years that prove otherwise. Many state and federal wildlife agencies are finding out that bears can and in certain areas are having measurable predatory affects on big game populations. Most studies revolve around the neonatal young, neonatal in generic terms relates to newborns within the first 28 days of life.
Bears are opportunistic omnivores, they respond to a wide variety of locally available food sources that are often seasonal, therefore are not obligate carnivores (Zager et al. 2006). This in theory means that bears don’t solely hunt moose calves or deer fawns. They would more likely to happen upon them during their daily activities and the result would be a tasty meal. However, there is also evidence in some studies that have followed radio-collared bears that indicates certain bears may learn and become more efficient at targeting neonatal offspring as well as adult pregnant females during the birthing seasons, especially older mature male bears.
Take note that all studies are done in varying habitats and species dynamics throughout the bear’s range, and that duplicating any one study would be impossible, so they all have different resulting statistics. Below is a very short list out of the many studies done on bear predation.
Boertje (Boertje et al. 1998) reported that adult male brown bears killed 3.3-3.9 adult moose annually, females without cubs killed 0.6-0.8 adult moose and 0.9-1.0 adult caribou annually, and each adult bear killed 5.4 moose calves in east central Alaska.
(Zager et al. 2006) In north-central Idaho in the mid-late 1970’s, 58% of 86 Rocky Mountain elk calves radio-collared shortly after birth and monitored until 1 October died from natural causes (Schlegel 1986). Of these, 98% died due to predation and 2% as a result of disease. Predation by black bears accounted for 66% of the total mortality by predators.
Annual elk calf mortality was 57% in Yellowstone National Park (Coughenour and Singer 1996). They reported that 32% of radio-marked calves died during summer and 21% died during winter. Nearly all summer mortality was due to predation by brown bears, 28%, black bears, 3%, and coyotes, 28%
(Kunkel, K.E. et al. 1994). White-tailed deer fawn mortality was studied during the summers of 1989 and 1990 in northeastern Minnesota. Estimated pooled mortality rates for 21 radio-tagged fawns were 0.44 for May-June, 0.13 for July-October, and 0.51 for May-October. Predation accounted for all mortalities, with wolves (Canis lupus) responsible for 51% of them and black bears (Ursus americanus) for 49%.
Penn State University and Pennsylvania Game Commission conducted a fawn survival survey in 2004. The results showed that black bears were eating almost as many fawn as coyotes, at respectively 33% for bears and 37% for coyotes. It was noted that these numbers could be even higher in areas where there is a lack of nesting and fawning cover under the forest canopy.
This again is just a minuscule list out of the studies that have been done on bear and prey dynamics. There are studies out there that result in smaller bear predation percentages; these were just a variety with eye-catching results. These results show there is no question that bears are very proficient big game predators. Studies show that most likely they do not hunt big game all year long. It is seasonal, just like the salmon runs or mast crops that bears in all habitats have learned to take advantage of for food sources. However, bears can live a long life upwards of 20+ years in the wild. Bear’s adaptability to the available food sources only gets better with age. They likely don’t wake up one morning and instinctively know they are going to hunt for a moose calf or deer fawn that day. That is until they smell that first calf or fawn of the season. This is a smell that they have learned comes with the possibility of an easy meal and then they instinctively turn to predator mode. They have also learned once they find the first victim of the season that for a short time there may be an abundance of neonatal offspring available, during which the older and wiser bears are actively hunting for their next high protein meal.
Some state wildlife departments have started offering multiple bear tags in certain units to help stabilize the predator and prey populations. Idaho offers two bear tags in certain areas where bear populations are on the rise, likely to help the elk numbers where wolves are also affecting the population. Alaska has a unit where they are now offering three bears tags to help stabilize the bear and moose populations. This points to the fact that scientific studies have consistently shown that bears of all sub-species are in fact very capable predators on many large game ungulates across North America and the World. It appears that bears alone will not likely create a large enough predatory affect to dramatically decrease most species all by themselves. However, most bears are sharing their home ranges with wolves or coyotes, and in fact sometimes both or even another sub species of bear. Combining the predatory effects of all of these predators along with other forms of natural death like disease and harsh winters on one population is taking its toll in some areas and causing wildlife agencies to adjust hunting regulations accordingly.
This fact is great for bear hunters. Bear populations are increasing all across the globe. With the realization that bears are proficient predators some states and provinces are offering multiple tags in units to allow hunters to help control the population through legalized hunting methods. There are many methods of hunting available throughout the country such as baiting, spot and stalk, and using hounds. Bear hunting is growing in popularity and is more readily accessible to people as there are now bear seasons offered all over North America, from the swamps of Florida all the way to the Arctic and many places in between. If you are a hunter and have never bear hunted, do yourself a favor and find a place to go on a bear hunt. Take advantage of these growing opportunities, you will not regret it.