By Clay Newcomb
Hunters have some relevant questions that need to be answered about bear home ranges. Do bear home ranges overlap? If you saw a giant bear in the summer near where you hunt, will he be there in the fall? Could a big bear that you’ve got pictures of on your hunting lease get killed 25 miles away? Are bears territorial? These are some questions we’ll seek to address in this article. Hunters often misunderstand bear home ranges, and make inaccurate assumptions about bears. Knowing more about your quarry will ultimately make you a better hunter, and understanding how bears utilize the landscape is important. The essence of hunting is finding game and getting close to it. Understanding the basics of bear home ranges will give us a better idea of what bruins are doing, how much they are traveling throughout the year and at different times of the year.
Biologists consider home range to be the area in which an animal lives and moves on a daily or periodical basis. This range would include the widest points of travel in a given year. A home range includes “core” areas where the bear spends more time, and fringe areas where the bear spends less time. Roger A. Powell of the University of North Carolina did a study on bear home ranges in the southern Appalachian Mountains. He noted that bear home ranges, though they may seem large, are used unevenly. There are multiple centers of activity in the range that clearly the bear prefers over other areas. These areas are the core areas of a bear’s home range.
Bears are “habitat generalists,” meaning they thrive off a wide variety of food types and habitat conditions, as opposed to “habitat specialists” that live off one main habitat type and food. Bears utilize their home range for no other reasons than these three: finding food and water, finding mates, and finding security. If a bear is wandering, he’s looking for something he doesn’t have right there. Home range is influenced by the availability of those three things.
Home Range Size
In a study titled “Dynamics of Home Range and Movements of Adult Black Bears in Northeastern Pennslyvania” by Pennsylvania State University, 17 bears were radio collared and their movements studied for three years. The total home range size for males averaged 66.7 square miles (173 square-kilometers). For females is averaged 15.83 square miles (41 square-kilometers). This would basically be equivalent to an area 8.1 miles by 8.1 miles for males, and 4 miles by 4 miles for a female. Male black bears maintained a home range about four times as large as females. A second study in Washington found a similar difference in home ranges sizes between males and females, stating that males had 3.8 times larger home ranges than females.
The biggest movements of males took place in during the spring breeding season in June and July. Peak breeding occurs mid-to-late June. However, the largest movement patterns for females with cubs took place September. Females with cubs covered larger geographic areas than females without cubs. However, sows with first-year cubs didn’t move as far as females with more mobile yearling cubs. A study in Florida that studied the home ranges of female black bears found that their fall range was twice as large as their summer range. Additionally, drought and environment stress that affected food availability cause bear ranges to widen. A study in Michigan also noted that some of the biggest movements of bears took place in the fall.
The home range size of female black bears in Manitoba was 114 square miles (295 km2), in Michigan 18.53 square miles (48 km2), in Arkansas 13.3 square miles (34.7 km2), and another study from the one stated above showed Pennsylvania female bears with a 27.79 square mile (72 km2) home range. It is assumed that the smaller the home range, the better the habitat and vice versa. If the habitat is extremely productive in food availability, bears don’t have to move very far. Habitat fragmentation is also thought to affect bear home range size. In the Canadian wilderness bears aren’t restricted by man-made barriers like interstate highways, or by urban fragmentation. Additionally, the Canadian boreal-forest habitat isn’t as productive (doesn’t produce as much food) as the temperate Eastern Decidious forests of North Carolina with nine months of moderate weather.
A study titled “Black Bear Home Range Overlap in North Carolina and the Concept of Home Range Applied to Black Bears” states that territoriality is related to habitat productivity, too. Where habitat is not as good and food is availability is less, bear ranges do not overlap as much. In regions like the southern Appalachians, where habitat productivity is high, there is much more home range overlap. Powell noted that female bears had broadly overlapping home ranges and did not exhibit exclusive use of any part of their range. In other words, you might find a bear on a ridge top one week and the next you might see a different bear. Also, some bear home ranges overlapped almost on top of one another, while other bears range just barely infringed on another bear’s range.
Powell believed that bears know their home ranges intricately and year-to-year move about them based upon past experiences and knowledge of where resources existed like seasonal food, or members of the opposite sex. Powell’s telemetry studies showed bears moving up to 1.5 miles in less than 2 hours. A bear’s home range size is determined not by rational choice, but by how big of area they need to supply their needs. Bears in Southeast Arkansas, in the lower White River drainage, have some of the smallest home ranges in the country because of the quality of habitat.
Are Bears Territorial?
An animal’s territory is an area that is actively defended. Most biologists would consider the home range and territory very similar. Male and female bears are both territorial. Multiple studies have shown that female bears are territorial towards other adult females, but tolerant of their own female offspring. This implies that limited resources are being defended. However, where resource is more available, territorialism decreases.
Male bears are also territorial, but their home ranges may overlap with multiple males. Territorial solitary carnivores, like mountain lions (pumas), exclude all males from their home ranges. Bears aren’t able to do this. However, radio telemetry studies in the Pigsah Bear Sanctuary in North Carolina show that males have large areas of range overlap, but they avoid using areas that other males are using. However, bears are highly territorial when food is scarce, and less territorial when food is abundant. This would explain how you might have multiple male bears at one single bait site. If there is plenty of food, and there isn’t an estrous female nearby, you might see adult males feed together.
Many would think that bears are territorial when it comes to breeding. They do fight other males for breeding dominance all year long. In a study done in Montana titled “Determinants of Male Reproductive Success in American Black Bears,” 28% of bear litters had cubs with different fathers (bears are promiscuous breeders capable of having multiple fathers from cubs in the same litter). This means that multiple males bred the same female. This indicates more than one male was around when she came into estrous. The study also indicated that not all male bears breed every year. There was .23 offspring produced per male in the area. This would roughly indicate that about ¼ of males actually breed. The study suggested that “encountering and courting a female before rivals arrive” is an important part of reproductive success, as opposed to keeping all rival males out of a territory. “Resident males were incapable of excluding males from their home ranges,” the author noted. It was interesting, he said, “black bears of all sizes searched widely for receptive females, but larger males had significantly higher encounter rates with receptive females, indicating superior ability to locate estrous females and to repel other bears from her vicinity.”
From this study, it appears that the older males stay within their home ranges during breeding period and try to service the females living within their range, as opposed to excessive roaming into new areas. It appears that the older males know where the females are and they go and check their receptivity often in the spring, thus all the moving around. However, they don’t just go on a huge walk-abouts into places they’ve never been. Males in this study stayed in their core home range about 40% of the time. Again, the core of the home range being the places in which they spend most of their time aside from the fringe areas.
Bears and Roads?
In a telemetry study done in Southeast Oklahoma, researchers from Oklahoma State University noted that bears avoided paved roads, especially high-speed or divided highways. However, bears appeared to favor using unpaved roads with less human activity. “We observed bears traveling such roads, and it appears these roads provided important travel corridors with little threat of mortality.” This study also noted the different forest types that bears preferred. In this region bears consistently avoided “pine-hardwood sawtimber stands”, but pine-hardwood and oak-hardwood poletimber stands were the highest ranked habitat types. This habitat type may not apply to where you hunt, but the principle is that they have a strong preference for the places they like to be. Their preferred hangouts, or the core areas of their range, will always have high-quality seasonal food, high prospects for mates (in the spring/summer), and security from threats. It goes without saying that they need water.
What does this mean for hunting?
The ideal situation for any type of bear hunting (bait, spot-and-stalk, or hounds) is to find an area with such good habitat that multiple bear ranges overlap. Your favorite bear canyon in Montana, your favorite swamp to bait in Michigan, or your favorite ridge top in North Carolina may just be that spot. These are spots where you can always go and find bear. However, lots of places are “fringy” and can waste your hunting time. The key is going to be determining what part of the range the bears are using when you are hunting (spring or fall). The best bait can’t pull and hold a bear for very long from the area he naturally wants to be in. The best hound can’t tree a bear that isn’t there, etc. Whatever type of hunting you’re doing, your success will increase when you determine where the core bear areas are – and there will be multiple core areas in the region you hunt. It isn’t just one single spot in a giant area of wilderness.
How do you find core bear areas? Understand the habitat and the seasonal food sources of the bears in your region. By boots-on-the-ground scouting and finding bear sign. Talk with the locals to see where bears are being seen. Test new areas to bait, or cast your hounds into some new canyons. Ultimately, a woodsman knows the ecology of the region he’s hunting, and correspondingly gains knowledge of where to find game. After a few years you’ll be able to pick out a core bear area much easier and will have more success bear hunting.
Research shows that most male bears on average have home ranges around 66 square miles, or roughly 8 miles by 8 miles (if they were square, which they are not). However, many studies have seen male bears travel much greater distances. A telemetry study in Arkansas had a collared male killed by a car in Oklahoma over 150 miles away from where it was captured. Researchers in Oklahoma currently have a mature male bear in their program that routinely makes a 65-mile trip (as the crow flies) between his summer and fall ranges. Home ranges are estimates and averages that give us a general idea of how bears use the land.