Kodiak bear

The Kodiak bear (Ursus arctos middendorffi), also known as the Kodiak brown bear and sometimes the Alaskan brown bear, inhabits the islands of the Kodiak Archipelago in southwest Alaska.^[3] It is one of the largest recognized subspecies or population of the brown bear, and one of the two largest bears alive today, the other being the polar bear.^[4][5] Kodiak bears are also considered by some to be a population of grizzly bears.

Physiologically and physically, the Kodiak bear is very similar to the other brown bear subspecies, such as the mainland grizzly bear (Ursus arctos horribilis) and the extinct California grizzly bear (U. a. californicus), with the main difference being size, as Kodiak bears are on average 1.5 to 2 times larger than their cousins. Despite this large variation in size, the diet and lifestyle of the Kodiak bear do not differ greatly from those of other brown bears.

Kodiak bears have interacted with humans for centuries, especially hunters and other people in the rural coastal regions of the archipelago.^[6] The bears are hunted for sport and are encountered by hunters pursuing other species. Less frequently, Kodiak bears are killed by people whose property (such as livestock) or person are threatened.^[7] In recent history there has been an increasing focus on conservation and protection of the Kodiak bear population as human activity in its range increases.^[6] The IUCN classifies the brown bear (Ursus arctos), of which the Kodiak is a subspecies, as being of "least concern" in terms of endangerment or extinction, though the IUCN does not differentiate between subspecies and thus does not provide a conservation status for the Kodiak population. The Alaska Department of Fish and Game, along with the United States Fish and Wildlife Service to a lesser extent, closely monitor the size and health of the population and the number of bears hunted in the state.^[6]

Taxonomist C.H. Merriam was the first to recognize the Kodiak bear as a unique subspecies of the brown bear, and he named it "Ursus middendorffi" in honor of the celebrated Baltic naturalist, Dr. A. Th. von Middendorff.^[2] Subsequent taxonomic work merged all North American brown bears into a single species (Ursus arctos). Genetic samples from bears on Kodiak have shown that they are most closely related to brown bears on the Alaska Peninsula and Kamchatka, Russia, and all brown bears roughly north of the US. Kodiak bears have been genetically isolated since at least the last ice age (10,000 to 12,000 years ago) and very little genetic diversity exists within the population.^[8] Although the current population is healthy, 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.

Hair colors range from pale blonde to orange (typically females or bears from southern parts of the archipelago) to dark brown. Cubs will often retain a white "natal ring" around their neck for the first few years of life. The Kodiak bear's color is similar to that of its close relatives, the mainland American Grizzly bear and Eurasian brown bears.^[9]

While there is generally much variation in size between brown bears in different areas, most usually weigh between 115 and 360 kg (254 and 794 lb);^[10] the Kodiak bear illustrates island gigantism, commonly reaching sizes of 300 to 600 kg (660 to 1,320 lb).^[3] The size range for females (sows) is from 181 to 318 kg (399 to 701 lb), and for males (boars), it is 272 to 635 kg (600 to 1,400 lb).^[3][11] Mature males average 477–534 kg (1,052–1,177 lb) over the course of the year,^[12] and can weigh up to 680 kg (1,500 lb) at peak times. Females are typically about 20% smaller and 30% lighter than males,^[3] and adult sizes are attained when they are six years old. Bears weigh the least when they emerge from their dens in the spring, and can increase their weight by 20–30%^[11] during late summer and autumn. As with other animals, captive Kodiak bears can sometimes weigh considerably more than their wild counterparts.

An average adult male measures 244 cm (8 ft 0 in) in length, and stands 133 cm (4 ft 4 in) tall at the shoulder. The largest recorded wild male weighed 751 kg (1,656 lb), and had a hind foot measurement of 46 cm (18 in).^[12] A large male Kodiak bear stands up to 1.5 m (4.9 ft) tall at the shoulder when it is standing on all four legs. When standing fully upright on its hind legs, a large male could reach a height of 3 m (9.8 ft).^[3] The largest verified size for a captive Kodiak bear was for a specimen that lived at the Dakota Zoo in Bismarck, North Dakota. Nicknamed "Clyde", he weighed 966 kg (2,130 lb) when he died in June 1987 at the age of 22. According to zoo director Terry Lincoln, Clyde probably weighed close to 1,089 kg (2,400 lb) a year earlier. He still had a fat layer of 9 in (23 cm) when he died.^[13][a].

Kodiak bears are the largest brown bear and are even comparable in size to polar bears. This makes Kodiak bears and polar bears the two largest members of the bear family and the largest extant terrestrial^[b] carnivorans.^[4]

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 78.1 cm (30.7 in), and eight of the top 10 brown bears listed in the Boone and Crockett record book are from Kodiak.^[17] The average skull size of Kodiak bears that were killed by hunters in the first five years of the 21st century was 63.8 cm (25.1 in) for boars, and 55.4 cm (21.8 in) for sows.^[18]

In addition, an individual named Teddy, which portrayed a killer bear in the movie Grizzly, stood 3.4 metres (11 ft) tall on its hind legs and was the largest bear in captivity at the time.

This brown bear population occurs only on the islands of the Kodiak Archipelago (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 population density of 270 bears per 1000 km² (700 per 1000 sq. mi). During the past decade [when?], the population has been slowly increasing.^[19]

Los osos de Kodiak son naturalmente activos durante el día , pero cuando se enfrentan a la competencia por alimento o espacio, adoptan un estilo de vida más nocturno (activos por la noche). Este comportamiento es especialmente evidente en los osos que viven cerca y dentro de la ciudad de Kodiak. Los osos de Kodiak no defienden territorios, pero sí tienen áreas tradicionales que utilizan cada año (áreas de campeo). Debido a la gran variedad de alimentos disponibles en Kodiak, los osos del archipiélago tienen algunas de las áreas de campeo más pequeñas de cualquier población de oso pardo en América del Norte ^{[ 20 ]} y se produce una gran superposición entre las áreas de campeo de los osos individuales. Las áreas de campeo de las hembras adultas en la isla de Kodiak tienen un promedio de 130 km² ⁽ 50 millas cuadradas), mientras que las de los machos tienen un promedio de 250 km² ⁽ 97 millas cuadradas). ^{[ 19 ]}

Las islas del archipiélago de Kodiak tienen un clima oceánico subpolar con temperaturas frescas, cielos nublados, niebla, vientos fuertes y precipitaciones de moderadas a intensas durante la mayor parte del año. Aunque el archipiélago solo abarca unos 13 000 km² ⁽ 5 000 millas cuadradas), presenta una rica variedad de topografía y vegetación, desde densos bosques de abeto de Sitka en las islas del norte, hasta escarpadas montañas glaciares que se elevan hasta el pico Koniag de 1360 m (4470 pies) a lo largo de la cordillera central de la isla de Kodiak, pasando por colinas onduladas y tundra plana en el extremo sur del archipiélago. Alrededor de 14 000 personas viven en el archipiélago, principalmente en la ciudad de Kodiak y sus alrededores , así como en seis aldeas periféricas. Las carreteras y otras alteraciones humanas se limitan generalmente a la isla de Afognak y la parte noreste de la isla de Kodiak. Aproximadamente la mitad del archipiélago está incluida en el Refugio Nacional de Vida Silvestre de Kodiak . ^{[ 19 ]}

Los osos de Kodiak comienzan a entrar en sus madrigueras a finales de octubre. Las hembras preñadas suelen ser las primeras en entrar; los machos, los últimos. Los machos comienzan a salir de sus madrigueras a principios de abril, mientras que las hembras con crías recién nacidas pueden permanecer en ellas hasta finales de junio. Los osos que viven en el extremo norte de la isla de Kodiak tienden a tener períodos de hibernación más largos que los osos de las zonas del sur. La mayoría de los osos de Kodiak excavan sus madrigueras en laderas de colinas o montañas y utilizan una amplia variedad de hábitats de hibernación dependiendo de la parte del archipiélago en la que vivan. Casi una cuarta parte de los osos adultos no hibernan, manteniéndose algo activos durante todo el invierno. ^{[ 3 ] [ 19 ]}

Kodiak bears reach sexual maturity at age five, but most sows are over nine years old when they successfully wean their first litter. The average time between litters is four years. Sows continue to produce cubs throughout their lives, but their productivity diminishes after they are 20 years old.^[21] Mating season for Kodiak bears is during May and June. They are serially monogamous (having one partner at a time), staying together from two days to two 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.^[3] Weighing less than 450 g (1 lb) at birth with little hair and closed eyes, they suckle for several months, emerging from the den in May or June, weighing 6.8–9.1 kilograms (15–20 pounds).^[3] Typical litter sizes on Kodiak are two or three cubs,^[3] with a long-term average of 2.4 cubs per litter.^[21] However, Kodiak bears have six functional nipples and can litter up to six cubs reportedly.^[22] Sows are sometimes seen with five or six cubs in tow, probably due to adopting cubs from other litters.^[3] Most cubs stay with their mothers for three years. Almost half of the cubs die before they leave,^[21] 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^[3] with roughly 56% of males and 89% of females surviving.^[19] Most young female bears stay within or near their mother's home range, while most males move farther away. Most adult sows die of natural causes (56%), while most adult male bears are killed by hunters (91%).^[19] The oldest known male bear in the wild was 27 years old, and the oldest female was 35.^[23]

Bears live throughout the archipelago, adapting to local resources and retaining relatively small home ranges and comparable densities in most habitats. With such a variety and abundance of food sources, bears are surprisingly intelligent in their eating habits. The first foods bears eat in the spring are emerging vegetation (such as grasses and forbs) and animals that may have died during the winter. This allows the bear to quickly replace the weight that was lost during hibernation. 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 consume the five species of Pacific salmon that spawn in local streams and lakes. Bears often prioritize the brain, flesh, and eggs of salmon for their high nutritional value. In the late summer and early fall, bears consume several types of berries when they reach their ripest point, and have the highest levels of sugar.^[24] As climate change causes elderberries to ripen earlier, berry season is now overlapping with salmon season and some bears are abandoning salmon runs to focus on the berries.^[25][19] Bears also feed on wind-rowed seaweed and invertebrates on some beaches throughout the year. When eating deer, mountain goats, elk, or cattle, internal organs are eaten first for their high-fat content, however even though there is an abundance of the animals found on the archipelago, few Kodiak bears actively prey on them as other methods of finding food are more energy efficient.^[24] Another food source available year-round is the garbage made by the human population of Kodiak Island.

The Kodiak bear is much like other brown bears in intelligence, although its tendency to feed in large dense groups leads to more complex social behaviors. 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 streams on Kodiak, up to 60 bears can be seen simultaneously in a 2.6 km² (1.0 sq mi) area. To maximize food intake at these ecologically important areas, bears have learned to minimize fighting and fatal interactions by developing a complex communication (both verbal and body posturing) and social structure.^[26]

Usually, Kodiak bears 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. However, there has been an increase in Kodiak encounters due to increases in the local population as well as increased hunting of Kodiak bears. Bear safety precautions aim at avoiding such situations, understanding bear needs and behavior, and learning how to recognize the warning signs bears give when stressed.^[27][28]

One fatal bear attack on a person on the Kodiak archipelago occurred in 1999.^[29] The National Geographic Society filmed a television program about brown bears, which included a segment on two brown bear attacks. Both incidents involved hunters who were hunting by themselves and were returning to game they had killed previously, and left alone in order to continue hunting. One of the attacks was fatal, with the hunter being killed by the bear, and occurred on Uganik Island (November 3, 1999), which is part of the Kodiak archipelago. In the other incident, after being attacked by the bear, the hunter stabbed it with a knife, then recovered his rifle and killed the attacking bear. This occurred on Raspberry Island, home to two full-service wilderness lodges. Prior to that, the last fatality was in 1921.^[30] About once every other year, a bear injures a person on Kodiak.^[31] In October 2021, a father and son hunting duo survived an attack from a Kodiak bear during an elk registration hunt on Afognak Island.^[32]

Early human occupants of the archipelago when the land was locked into the ice age 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 the mystical nature of bears because of their proximity to the spirit world.^[33]

Russian hunters came to the area in the late 18th century 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,^[34] 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.^[30]

Professional interest in guided Kodiak bear hunts and 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 in northeast Kodiak reported an increase in bear problems and demanded action. Bears were wrongly 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.^[33] The 7,700 km² (1,900,000 acres) refuge roughly encompasses the southwestern two-thirds of Kodiak Island, Uganik Island, the Red Peaks area on northwestern Afognak Island, and all of Ban Island.

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.^[35] Despite public pressure, the state continued actively pursuing and dispatching problem bears until 1970.^[36]

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 the passage of the Alaska National Interest Lands Conservation Act in 1980 (ANILCA), and the Kodiak National Wildlife Refuge lost control of 130,000 hectares (310,000 acres) of prime bear habitat (more than 17% of refuge lands).^[33]

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 10 km (6 mi) 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 the establishment of the Kodiak Brown Bear Trust.^[37] 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.

Los osos no sufrieron daños directos por el derrame de petróleo del Exxon Valdez en 1989, aunque algunos fueron desplazados de sus zonas habituales de alimentación y desplazamiento por los equipos de limpieza. Nadie resultó herido por un oso, y ningún oso de Kodiak murió. Para mitigar los efectos adversos del derrame, Exxon llegó a un acuerdo con los gobiernos estatal y federal. Paradójicamente, los efectos del derrame de petróleo, la posterior limpieza y el acuerdo resultaron beneficiosos para los osos de Kodiak. La capacitación en seguridad con osos brindó a miles de trabajadores información veraz sobre estos animales, y los fondos del acuerdo se utilizaron para financiar la adquisición de tierras. A finales del siglo XX, más del 80 % de las tierras del refugio que se habían perdido como resultado de la Ley de Conservación de Tierras de los osos (ANCSA) y la Ley de Conservación de Tierras de los osos de los ríos (ANILCA) se reintegraron al refugio, ya sea mediante compra directa o mediante servidumbres de conservación. También se adquirieron tierras en America, Westtown y las islas Shuyak , y se transfirieron a la propiedad estatal. El Kodiak Brown Bear Trust coordinó una coalición de cazadores y otros grupos de conservación de la vida silvestre de todo el país para presionar a favor del uso de fondos de compensación para adquirir tierras de Kodiak. Los grupos también contribuyeron directamente con fondos para proteger pequeñas parcelas de hábitat importante para los osos alrededor de las islas. ^{[ 33 ]}

En 2001, se creó un comité asesor ciudadano para colaborar estrechamente con el Departamento de Pesca y Caza de Alaska (ADF&G), con la cooperación del Refugio Nacional de Vida Silvestre de Kodiak (Kodiak NWR), en el desarrollo de un plan de gestión que abordara diversos problemas que afectan a los osos, como la caza, el hábitat y la observación. El Plan de Conservación y Gestión del Oso del Archipiélago de Kodiak ^{[ 38 ]} resultante fue elaborado durante varios meses por representantes de 12 grupos de usuarios diversos, quienes, tras escuchar a varios expertos de agencias y recibir amplia participación pública, desarrollaron más de 270 recomendaciones para la gestión y conservación de los osos de Kodiak. A pesar de la diversidad de puntos de vista expresados ​​por los miembros del grupo, todas las recomendaciones fueron consensuadas.

Los temas centrales de las recomendaciones fueron la conservación continua de la población de osos en su nivel actual, el aumento de los programas educativos para enseñar a la población a convivir con los osos en Kodiak y la protección del hábitat de los osos, permitiendo el uso humano continuo del archipiélago. Si bien el papel del grupo es meramente consultivo, las agencias gubernamentales de gestión expresaron su compromiso de implementar todas las regulaciones que fueran factibles y estuvieran dentro de sus jurisdicciones legales.

La Lista Roja de la Unión Internacional para la Conservación de la Naturaleza no incluye subespecies. La especie de oso pardo, a la que pertenece la subespecie Kodiak, figura como de Riesgo Bajo o Preocupación Menor. ^{[ 39 ]} El oso Kodiak no figura como especie en peligro de extinción según la Ley de Especies en Peligro de Extinción del Servicio de Pesca y Vida Silvestre de los Estados Unidos . ^{[ 40 ]}

La investigación sobre el oso Kodiak y la protección de su hábitat se llevan a cabo en colaboración entre el Departamento de Pesca y Caza de Alaska (ADF&G) y el Refugio Nacional de Vida Silvestre de Kodiak. La caza del oso está a cargo del ADF&G, y la Junta de Caza de Alaska establece las normas de caza. Actualmente, un sistema de gestión optimizado distribuye a los cazadores en 32 áreas diferentes durante dos temporadas (primavera: del 1 de abril al 15 de mayo, y otoño: del 25 de octubre al 30 de noviembre). Cada año, aproximadamente 4500 personas solicitan los 496 permisos disponibles para la caza del oso Kodiak (dos tercios para residentes de Alaska y un tercio para no residentes). Los no residentes deben contratar a un guía registrado y autorizado para cazar en la zona, cuyo costo oscila entre $10 000 y $22 000. Todos los cazadores deben presentarse en la oficina del Departamento de Pesca y Caza de Alaska en Kodiak antes de salir al campo para recibir una breve orientación y deben registrarse antes de abandonar la isla. Todo oso que se mate legalmente en el archipiélago debe ser inspeccionado por un biólogo de vida silvestre del ADF&G antes de que pueda ser sacado de las islas. ^{[ 41 ]} Las pieles reciben una etiqueta de seguridad metálica de un oficial del ADF&G si el cazador y el guía proporcionan la documentación adecuada para probar la licencia. Las pieles no pueden transportarse, conservarse legalmente ni venderse sin la etiqueta de seguridad metálica oficial. También se coloca una etiqueta en el cráneo, que se mide y registra. Las leyes de caza son aplicadas estrictamente por los oficiales del ADF&G, quienes a menudo cuentan con el pleno apoyo de la comunidad local. La caza y la pesca ilegales son mal vistas por la comunidad, que también mantiene un sano respeto por las leyes ambientales de la isla. La caza y la pesca ilegales conllevan severas sanciones. La ubicación remota de la isla dificulta el tráfico de pieles ilegales para los posibles cazadores furtivos.

Since statehood, the reported number of Kodiak bears killed by hunters has ranged from 77 (1968–1969) to 206 (1965–1966). From 2000 to 2006, an average of 173 Kodiak bears were killed by hunters each year (118 during the fall season and 55 in the spring season). Over 75% of those were males. An additional nine bears were reported killed annually in defense of life or property during the same time. The number of large, trophy-sized bears (total skull size at least 70 cm [28 inches]) killed by hunters in recent years has been increasing. 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%.^[18]

In the past 20 years, bear viewing has become increasingly 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 development of additional bear viewing areas on Kodiak is planned. Also, other bear viewing opportunities exist 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 affect several bears, especially productive sows with cubs. Often, 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.^[38]

The bear is important to the Alutiiq people. Its Alutiiq name is Taquka’aq (Bear),^[42][43] with the pronunciation varying between Northern and Southern dialects.^[44]

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