Kodiak Bear

From Wikipedia, the free encyclopedia

Kodiak Bear
Female Kodiak bear with cubs
Conservation status
Least Concern (IUCN 3.1)[1]
Scientific classification
Kingdom: Animalia Phylum: Chordata Class: Mammalia Order: Carnivora Family: Ursidae Genus: Ursus Species: U. arctos Subspecies: U. a. middendorffi
Trinomial name
Ursus arctos middendorffi
Kodiak Bear range

The Kodiak bear (Ursus arctos middendorffi) is a large subspecies of brown bear that occupies the islands of the Kodiak Archipelago in southcentral Alaska. The traditional name in the Alutiiq language is: Taquka-aq. Male bears are referred to as boars, while females are called sows.

Contents 1 Description 1.1 Taxonomy 1.2 Color 1.3 Size 1.3.1 Size relative to other bear types 1.4 Distribution and density 2 Life history 2.1 Reproduction and survival 2.2 Denning 2.3 Home Range 2.4 Habitat and feeding habits 3 Behaviour 3.1 Sensory perception and intelligence 3.2 Interactions with other bears 3.3 Interactions with people 4 History and management 4.1 Prehistory 4.2 Commercial harvests 4.3 Guided hunters and competition for resources 4.4 Changes in land status 4.5 Kodiak Bear Plan 4.6 Genetic diversity and Endangerment 4.7 Hunt management 4.8 Bear viewing 5 References

[edit] Description

[edit] Taxonomy

Taxonomist C.H. Merriam was the first to recognize Kodiak bears as unique and he named the species in honor of the celebrated Russian naturalist Dr. A. Th. von Middendorff ^[2]. Subsequent taxonomic revisions merged most North American brown bears into a single subspecies (Ursus arctos horribilis), but Kodiak bears are still considered to be a unique subspecies (Ursus arctos middendorffi). Recent investigations of genetic samples from bears on Kodiak have shown that they are closely related to brown bears on the Alaska Peninsula and Kamchatka, Russia. It appears that Kodiak bears have been genetically isolated since at least the last ice age (10,000 to 12,000 years ago) and there is very little genetic diversity within the population ^[3]. Although the current population is healthy and productive, and has shown no overt adverse signs of inbreeding, it may be more susceptible to new diseases or parasites than other more diverse brown bear populations.

[edit] Color

Hair colors range from blond (typically females or bears from southern parts of the archipelago) to dark brown. Cubs often retain a white “natal ring” around their neck for the first couple years of life. Male bears are referred to as boars, while females are called sows.

[edit] Size

Few Kodiak bears have been weighed in the wild, but estimates for exceptionally large males in the autumn range from 1,200 – 1,500 lbs (550 – 680 kg). Weights vary by gender, age and time of year. Males are typically about 30% larger than females and adult sizes are attained when bears are 6 years old. Bears weigh the least when they emerge from their dens in the spring, and can increase their weight by over 50% during late summer and fall. Bears in captivity can sometimes attain weighs that are double those seen in wild bears.

An adult male Kodiak bear stands about 5 ft (1.5 m) tall at the shoulder when it is standing normally. When standing up on its hind legs, the same bear could reach a height of 10 – 11 ft (3.0 – 3.4 m). The average weight of the males over the course of the year is 477-534 kg (1,050-1,175 lb).^[4] When hunters refer to a 10-foot (3.0 m) bear, they are estimating the size of the skinned-out hide by adding the length (nose to base of tail) and the width (tip of left center front claw to tip of right center front claw) and dividing that sum by 2. This measurement is extremely variable due to hide shrinkage or stretching, rendering it impossible to use as a reliable way to compare bears.

The standard method of evaluating the size of bears is by measuring their skulls. Most North American hunting organizations and management agencies use calipers to measure the length of the skull (back of sagittal crest on the back of the skull to the front tooth) and the width (maximum width between the zygomatic arches - “cheek bones”). The total skull size is the sum of these two measurements. The largest bear ever killed in North America was from Kodiak Island with a total skull size of 30.75 in (78.1 cm), and 8 of the top 10 brown bears listed in the Boone and Crockett record book are from Kodiak ^[5]. The average skull size of Kodiak bears that were killed by hunters in the first 5 years of the 21st century was 25.1 in (63.8 cm) for boars and 21.8 in (55.4 cm) for sows ^[6].

[edit] Size relative to other bear types

The Kodiak bear and the polar bear are the largest members of the bear family^[7]. Physically, Kodiak bears are similar to the Kamchatka Brown Bears of the Russian Far East, though tending to be lighter in colour and bigger.^[8]

[edit] Distribution and density

Although the term “Kodiak bear” is widely used to include all coastal Alaska brown bears, the subspecies only occurs on the islands of the Kodiak Archipelago, Alaska (Kodiak, Afognak, Shuyak, Raspberry, Uganik, Sitkalidak, and adjacent islands). The Kodiak bear population was estimated to include 3,526 bears in 2005, yielding an estimated archipelago-wide density of 0.7 bears/square mile (271.2 bears/1000 km2). During the past decade the population has been slowly increasing ^[9].

[edit] Life history

[edit] Reproduction and survival

Mating season for Kodiak bears is during May and June. They are serially monogamous (having one partner at a time), staying together for a couple days or a couple weeks. As soon as the egg is fertilized and divides a few times, it enters a state of suspended animation until autumn when it finally implants on the uterine wall and begins to grow again. Cubs are born in the den during January or February. Weighing less than a pound (>500 g) at birth with little hair and closed eyes, they suckle for several months, emerging from the den in May or June, weighing 15-20 pounds (7-9 kg). Typical litter sizes on Kodiak are 2-3 cubs, with a long-term average of 2.4 cubs per litter ^[10]. Sows are sometimes seen with 5 or 6 cubs in tow, probably due to adopting cubs from other litters ^[11]. Most cubs stay with their mothers for 3 years. Almost half of the cubs die before they leave ^[10], with cannibalism by adult males being one of the major causes of death.

Kodiak bears that have recently left their mothers, at ages 3-5 years, have high mortality rates with only 56% of the males and 89% of the females surviving ^[9]. Most young female bears stay within or near their mother’s home range, while most males move farther away. Kodiak bears become sexually mature at age 5, but most sows are over 9 years old when they successfully wean their first litter. The average interval between litters is about 4 years. Sows continue to produce cubs throughout their lives but their productivity diminishes after they are 20 years old. <^[10]. The most adult sows die natural causes (56%) while most adult boars are killed by hunters (91%) ^[9].

[edit] Denning

Kodiak bears begin entering their dens in late October. Pregnant sows are usually the first to go to dens, males are the last. Males begin emerging from their dens in early April, while sows with new cubs may stay in dens until late June. Bears living on the north end of Kodiak Island tend to have longer denning periods than bears in the southern areas. Most Kodiak bears dig their dens in hill or mountain sides and they use a wide variety of denning habitats depending on which part of the archipelago they live on. Almost a quarter of the adult boars forego denning, staying somewhat active throughout the winter ^[9].

[edit] Home Range

Bears on Kodiak are naturally diurnal (active during the day), but when faced with competition for food or space, they adopt a more nocturnal (active at night) lifestyle. This behavior is especially evident in the bears that live near and within Kodiak City. Kodiak bears do not defend territories, but they do have traditional areas that they use each year (home ranges). Because of the rich variety of foods available on Kodiak, the bears on the archipelago have some of the smallest home ranges of any brown bear populations in North America ^[12] and there is a great deal of overlap among the ranges of individual bears. Home ranges of adult sows on Kodiak Island average 50 mi (80 km)² (129 km²), while boar home ranges average 97 mi (156 km)² (250 km²) ^[9].

[edit] Habitat and feeding habits

The islands of the Kodiak archipelago have a subarctic maritime climate with cool temperatures, overcast skies, fog, windy conditions and moderate to heavy precipitation throughout the most of the year. Although the archipelago only covers about 5,000 mi2 (13,000 km2) there is a rich variety of topography and vegetation that ranges from dense forests of Sitka spruce on the northern islands, to steep glaciated mountains rising to 4,405 ft (1,362 m) along the central spine of Kodiak Island, to rolling hills and flat tundra on the south end of the archipelago. There are about 14,000 people that live on the Archipelago, primarily in Kodiak city and 6 outlying villages. Roads and other human alterations are generally limited to Afognak Island and the northeastern part of Kodiak Island. About half of the Archipelago is included in the Kodiak National Wildlife Refuge ^[9].

Bears live throughout the archipelago, adapting to local resources and retaining relatively small home ranges and comparable densities in most habitats. Emerging vegetation and animals that died during the winter are the first foods bears use in the spring. As summer progresses a wide variety of vegetation supplies nutritional needs until salmon return. Salmon runs extend from May through September on most of the Archipelago and bears make extensive use of the 5 species of Pacific salmon that spawn in local streams and lakes. In the late summer and early fall, bears consume several types of berries. Bears also feed on wind-rowed seaweed and invertebrates on some beaches throughout the year. Although deer, elk and mountain goats are abundant on the archipelago, few Kodiak bears actively prey on them ^[9].

[edit] Behaviour

[edit] Sensory perception and intelligence

There have been no scientific studies evaluating the sensory perception or intelligence of Kodiak bears. Subjective observations and comparisons to other bears suggest that Kodiak bears have eyesight that is comparable to humans (they are not “near sighted”), have hearing that is comparable to an average dog, and have a sense of smell that is up to 4 times more acute than the average dog. Their level of intelligence seems to be somewhere between that of an average canine and a primate. Due to their level of intelligence, individual bears have personalities and unique ways of dealing with situations^[13].

[edit] Interactions with other bears

Kodiak bears are generally solitary in nature; however, when food is concentrated in small areas, such as along salmon spawning streams, grass/sedge flats, berry patches, a dead whale, or even an open garbage dump they often occur in large groups. Along a few drainages on Kodiak, up to 60 bears can been seen simultaneously in a square mile area (2.6 km²). To maximize food intake at these important areas, bears have learned to minimize fighting and fatal interactions by developing a complex language (both verbal and body posturing) and social structure ^[13].

[edit] Interactions with people

In most circumstances, Kodiak bears are generally shy and attempt to avoid encounters with people. The most notable exceptions to this behavior pattern occur when bears are surprised, threatened, or attracted by human food, garbage, or hunter-killed game. Bear safety precautions center around avoiding such situations, understanding bear needs and behavior, and learning how to recognize the warning signs bears give when stressed ^{[14] [15]}.

The most recent occurrence of a fatal bear attack on a person on the Kodiak archipelago was in 1999 ^[16]. Prior to that, the last fatality was in 1921 ^[17]. Both incidents involved hunters that were hunting by themselves. About once every other year a bear injures a person on Kodiak ^[18].

[edit] History and management

[edit] Prehistory

Early human occupants of the archipelago looked to the sea for their sustenance. At that time, Kodiak Natives (Alutiiqs) occasionally hunted bears, using their meat for food, hides for clothing and bedding, and teeth for adornment. Traditional stories often revolved around the similarity between bears and humans, and around the mystical nature of bears because of their proximity to the spirit world ^[19].

[edit] Commercial harvests

Russian entrepreneurs came to the area in the late 1700s to capitalize on the abundant fur resources. Bear hides were considered a “minor fur” and sold for about the same price as river otter pelts. The number of bears harvested increased substantially when sea otter populations declined and after the United States acquired Alaska in 1867, bear harvests on Kodiak increased, peaking at as many as 250 bears per year. Commercial fishing activities increased in the late 1880s and canneries proliferated throughout the archipelago. Bears were viewed as competitors for the salmon resource and were routinely shot when seen on streams or coasts. At the same time, sportsmen and scientists had recognized the Kodiak bear as the largest in the world, and they voiced concerns about overharvesting the population ^[17].

[edit] Guided hunters and competition for resources

Professional interest in guided Kodiak bear hunts and a concern for unregulated resource use in frontier lands such as Alaska prompted the territorial government’s newly established Alaska Game Commission to abolish commercial bear hunting (selling the hides) on the archipelago in 1925. The impacts of the new regulations seemed to restore bear populations on the Kodiak islands. By the 1930s, ranchers on northeast Kodiak reported an increase in bear problems and demanded action. Bears were also seen as a threat to the expanding commercial salmon fishing industry. To address the dilemma of conserving bears while protecting cattle, salmon and people, President Franklin D. Roosevelt created the Kodiak National Wildlife Refuge by Executive Order in 1941 ^[19].

Alaska achieved statehood in 1959 and assumed responsibility for managing the state’s wildlife. The Alaska Board of Game reduced bear-hunting seasons on Afognak and Raspberry islands and on the Kodiak National Wildlife Refuge, but liberalized bear seasons on non-refuge lands on Kodiak. During the 1960s, state biologists worked with ranchers along the Kodiak road system to examine and reduce the predation problem. Biologists reported that cattle and bears were not compatible on the same ranges and potential solutions included poisons, fences to isolate cattle ranges, and aerial shooting of bears. Again, sport hunters voiced their support for Kodiak bears. In spite of public pressure, the state continued actively pursuing and dispatching problem bears until 1970 ^[20].

[edit] Changes in land status

In 1971, the Alaska Native Claims Settlement Act (ANCSA) resolved many long-standing land issues with aboriginal Alaskans statewide. The impacts were felt strongly on the archipelago as large areas were conveyed to the Native corporations. Federal management of the National Forest lands on Afognak was transferred to Native Corporation ownership with passage of the Alaska National Interest Lands Conservation Act (ANILCA) in 1980, and the Kodiak National Wildlife Refuge lost control of 310,000 acres (1,300 km²) of prime bear habitat (more than 17 % of refuge lands) ^[19].

In 1975, construction of a logging road began on Afognak Island, and timber harvesting began in 1977. In 1979, work began on an environmental impact statement for the Terror Lake hydroelectric project on Kodiak Island. That project included an earthen dam on Terror Lake with Kodiak National Wildlife Refuge and a 6-mile (9.7 km)–long tunnel through a mountain ridge to a penstock and powerhouse in the Kizhuyak River drainage. The hydro project was the first significant invasion of inland bear habitat on Kodiak Island. To address the opposition encountered from the public and agencies, a mitigation settlement was negotiated in 1981 which included brown bear research and establishment of the Kodiak Brown Bear Trust ^[21]. The hydroelectric project was completed in 1985. Human alteration of bear habitat on Kodiak and Afognak islands spurred renewed interest and funding for bear research on the archipelago, resulting in a surge of baseline and applied bear research on Kodiak through the 1980s and 1990s.

Bears were not directly harmed by the Exxon Valdez oil spill in 1989, although some were displaced from traditional feeding and traveling areas by cleanup crews. No one was injured by a bear, and no Kodiak bears were killed. To mitigate the adverse impacts of the spill, Exxon reached a settlement with the state and federal governments. Paradoxically, the impacts of the oil spill and the subsequent cleanup and settlement proved to be beneficial to bears on Kodiak. Bear-safety training exposed thousands of workers to factual information about bears, and money from the settlement fund was used for funding land acquisitions. By the close of the 20th century, over 80% of the refuge lands that had been lost as a result of ANCSA and ANILCA were reinstated into the refuge, either through direct purchase or by means of conservation easements. Lands were also purchased on Afognak and Shuyak islands and transferred into state ownership. The Kodiak Brown Bear Trust coordinated a coalition of sportsmen and other wildlife conservation groups from around the nation to lobby for use of settlement funds to acquire Kodiak lands. The groups also directly contributed funding to protect small parcels of important bear habitat around the islands ^[19].

[edit] Kodiak Bear Plan

In 2001 a Citizens Advisory Committee was established to work closely with the Alaska Department of Fish and Game, with the cooperation of Kodiak NWR, to develop a management plan addressing the wide variety of issues that affect bears, including hunting, habitat, and viewing. The resulting Kodiak Archipelago Bear Conservation and Management Plan ^[22] was crafted over a several month period by a group of representatives from 12 diverse user groups. After hearing from a variety of experts from agencies and receiving extensive public input, the group developed more than 270 recommendations for Kodiak bear management and conservation. Most impressively, in spite of the diversity of viewpoints expressed by members of the group, all of the recommendations were by consensus.

The underlying themes of the recommendations were continued conservation of the bear population at its current level, increased education programs to teach people how to live with bears on Kodiak, and protection of bear habitat with allowances for continued human use of the Archipelago. Although the group was advisory in nature, government management agencies expressed a commitment to work to implement all of the regulations that were feasible and within their legal jurisdictions.

[edit] Genetic diversity and Endangerment

The brown bear is listed as LR/lc (Lower Risk Least Concern)^[1], and it is not listed as a endangered species by the Endangered Species program of the US Fish and Wildlife service^[23].

[edit] Hunt management

Kodiak bear research and habitat protection is done cooperatively by the Alaska Department of Fish & Game and Kodiak National Wildlife Refuge. Bear hunting is managed by the Alaska Department of Fish and Game and hunting regulations are established by the Alaska Board of Game. There is currently a finely tuned management system that distributes hunters in 32 different areas during two seasons (spring: April 1 – May 15, and fall: October 25 – November 30). Each year about 4,500 people apply for the 496 permits offered for Kodiak bear hunts (two-thirds to Alaska residents, one-third to nonresidents). Nonresidents are required to hire a registered guide who is authorized to hunt in a particular area, and this can cost from $10,000 - $22,000. All hunters must come into the Alaska Department of Fish and Game office in Kodiak prior to going into the field for a brief orientation and must check out before they leave the island. Every bear that is legally killed on the Archipelago must be inspected by an Alaska Department of Fish and Game wildlife biologist before it can be taken from the islands ^[24].

Since statehood, the reported number of Kodiak bears killed by hunters has ranged from 77 (1968–69) to 206 (1965–66). From 2000 – 2006, an average of 173 Kodiak bears was killed by hunters each year (118 during the fall season and 55 in the spring season). Over 75% of those were males. An additional 9 bears were reported killed annually in defense of life or property during the same time period. There has been an increasing number and percentage of large, trophy-sized boars (total skull size at least 28”) killed by hunters in recent years. In the 1970s, only 2.5% of the bears killed on Kodiak were trophy-sized; in the 1990s and 2000s the proportion increased to almost 9% ^[6].

[edit] Bear viewing

In the past 20 years bear viewing has become increasing popular on Kodiak and other parts of Alaska. The most accessible bear viewing location on Kodiak, Frazer River, had over 1,100 people come in 2007. Visitor numbers have been increasing at about 10% annually and there are plans for development of additional bear viewing areas on Kodiak. There are also other bear viewing opportunities through air-taxi, charter boat, remote lodge and trekking operations on the Archipelago.

Although bear viewing is often considered a “non-consumptive” use, it can have serious impacts on bear populations if it is not conducted properly. Most viewing occurs at places where bears congregate because of feeding opportunities that are critical to their survival. If some bears avoid these areas because people are there, those bears may not get the fat and protein they need to make it through the upcoming winter. Consequently unmanaged bear viewing could impact several bears, especially productive sows with cubs.

Often times bear viewing and bear hunting are considered incompatible. Even if the bear population is healthy and bear hunting is sustainable, ethical questions arise especially if hunting occurs near viewing areas and either during or soon after the viewing season. Many feel that it is not fair to encourage bears to be close to people during the summer only to allow them to be shot in the fall. The Kodiak bear plan recognized bear hunting as a legitimate, traditional, and biologically justifiable activity. It recommended that agencies find ways to make bear hunting and bear viewing compatible on the Archipelago ^[22].

[edit] References

1. ^ ^{a b} Ursus arctos. IUCN International Union for Conservation of Nature. Retrieved on 2008-03-22.
2. ^ Merriam, C. H. 1896. Ursus middendorffi. 69–71. Proceedings of the Biological Society of Washington.
3. ^ Talbot, S. L. J. R. Gust, G. K. Sage, A. Fischbach, K. Amstrup, W. Leacock, and L.Vav Daele. 2006. Genetic characterization of brown bears of the Kodiak Archipelago. Final report to the Kodiak National Wildlife Refuge, Kodiak Alaska, USA.
4. ^ Wood, The Guinness Book of Animal Facts and Feats. Sterling Pub Co Inc (1983), ISBN 978-0851122359
5. ^ Buckner, E. L. and J. Reneau. 2005. Records of North American Big Game. Boone & Crockett Club; 12.00 edition (October 1, 2005).
6. ^ ^{a b} Van Daele, L.J. 2005 (July 2002 – 30 June 2004). Brown bear management report of survey and inventory activities1. Unit 8 brown bear management report. Pages 74-101 in C. Brown, editor. Alaska Department of Fish and Game, Juneau, Alaska, USA. Retrieved on 2008-04-30.
7. ^ Polar bear, (Ursus maritimus). U.S. Fish and Wildlife service. Retrieved on 2008-03-22. “Appearance. The polar bear is the largest member of the bear family, with the exception of Alaska’s Kodiak brown bears, which equal polar bears in size.”
8. ^ Join the Russian Hunting Agency for a Brown Bear Hunt. Russian Hunting Agency. Retrieved on 2008-03-22.
9. ^ ^{a b c d e f g} Van Daele, L.J. 2007. Population dynamics and management of brown bears on Kodiak Island, Alaska. Doctoral dissertation. University of Idaho, Moscow, USA. Retrieved on 2008-04-30.
10. ^ ^{a b c} Barnes, V.G. and L.J.Van Daele. 2006. Productivity of female brown bears on Kodiak Island, Alaska. Job completion report for Challenge Cost Share Project. Kodiak National Wildlife Refuge, Kodiak, Alaska, USA.
11. ^ Barnes, V.G. 1993. Cub Adoption by Brown Bears, Ursus arctos middendorffi, on Kodiak Island, Alaska. The Canadian Field-Naturalist 107:365-367.
12. ^ McLoughlin, P.D., S. H. Ferguson, AND F. Messier, 2000. Intraspecific variation in home range overlap with habitat quality: a comparison among brown bear populations. Evolutionary Ecology 14:39-60.
13. ^ ^{a b} Wood, Jason. 2006. Kodiak kings. Nodin Press, Minneapolis, Minnesota. USA
14. ^ Quinth, Stefan (2006). A guide to brown bear country (DVD). Camera Q Productions. Retrieved on 2008-04-30.
15. ^ Alaska’s bears webpage. Alaska Department of Fish and Game, Division of Wildlife Conservation (2008). Retrieved on 2008-04-30.
16. ^ Karen Aho. Wounds, not cold, killed hunter exam finds. Anchorage Daily News. Retrieved on 2008-04-30.
17. ^ ^{a b} Dodge, Harry B. 2004. Kodiak Island and it’s bears. Great Northwest Publishing and Distributing Company. Anchorage, Alaska USA
18. ^ Alaska Department of Fish and Game files, 211 Mission Road, Kodiak, Alaska 99615 USA
19. ^ ^{a b c d} Van Daele, L.J. 2003. The History of Bears on the Kodiak Archipelago. Alaska Natural History Association. Anchorage, Alaska, USA.
20. ^ Troyer, W. 2005. Into brown bear country. University of Alaska Press. Fairbanks, Alaska USA.
21. ^ Smith, R. B., AND L. J. Van Daele. 1990. Impacts of hydroelectric development on brown bears, Kodiak Island, Alaska. International Conference on Bear Research and Management 8:93–103.
22. ^ ^{a b} Kodiak Archipelago Bear Conservation and Management Plan. Alaska Department of Fish and Game, Anchorage, USA. Alaska Department of Fish & Game (2002). Retrieved on 2008-04-30.
23. ^ Endangered Species program, list of mammals endangered on the US. US Fish and Wildlife service. Retrieved on 2008-03-22.
24. ^ Hunting Kodiak bears – a question and answer guide. Alaska Department of Fish and Game (2008). Retrieved on 2008-04-30.