Tag Archives: Roosevelt Elk

Roosevelt Elk (Cervus elaphus roosevelti)

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In 1928, eight yearling Roosevelt Elk (Cervus elaphus roosevelti) were introduced from the Ho Valley on the Olympic Peninsula of Washington State to Kodiak Island where they were raised for one year at the Experimental Agricultural Research Station in Kalsin Bay near the town of Kodiak. Biologists originally planned to release the elk on Kodiak Island, but ranchers on the island were concerned the elk would compete with their cattle for the limited winter food supply, so in 1929, biologists instead transplanted the elk to Afognak Island, a large island in the Kodiak Archipelago just north of Kodiak. By 1965, the herd had expanded from the original eight calves to between 1,200 and 1,500 elk, and the population had spread to nearby Raspberry Island. Several harsh winters with heavy snowfalls in the late 1960s and early 1970s caused increased mortality and reduced calf production in the herd, but by the 1980s, the herd had recovered to 1,200 animals. Today in the late 2000s, approximately 900 elk live on Afognak and Raspberry Islands. The only other elk in Alaska are Rocky Mountain Elk (Cervus elaphus nelson) that were introduced from Oregon to Etolin Island in Southeast Alaska in 1987. This herd has now expanded to Zarembo Island.

Elk are members of the deer family. They are larger than deer and caribou but smaller than moose. An elk’s body is gray to brown in color, with dark brown legs and a brown neck. A large, yellow patch covers the rump. Males have antlers that can grow very large. The antlers sweep back over the shoulders, and the spikes point forward. Bulls shed their antlers in the winter and grow new ones the following summer.

Elk give birth in late May or early June, and soon after giving birth, cow elk and their calves band together. Sometimes one cow elk will babysit the calves while the other mothers search for food. By July, the calves are still nursing but begin to eat on their own. In August, bands of elk come together to form herds, consisting of cows, calves, yearlings and sometimes a mature bull. Small bands of bulls form nearby but separate from the herd. In September, the bulls join the main herd for the mating season. During this time, bulls challenge each other by emitting high-pitched whistles or “bugles” and sometimes push and shove each other with their large antlers. By mid-October, once breeding has ended, the herds disperse into smaller bands, and the elk move into their wintering areas in the lower valleys or near the coastline where they search for food.

Elk graze from late spring to early fall when there is more food available, including grasses, forbs, and other leafy vegetation. By late fall, they mainly browse, feeding on sprouts and branches of trees and shrubs. Elk are big animals that require a large amount of food, and since they live in herds, they can quickly over-graze their food supply and decimate the native vegetation.

Biologists estimate 900 elk live in seven herds on Afognak Island and one herd on Raspberry Island. Logging on Afognak Island has impacted elk habitat there, but biologists consider the herd to be healthy.  Elk occasionally swim to Kodiak Island, but while individual elk have been seen on Kodiak, no herd has become established there.

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Mammals Introduced to Kodiak Island

Kodiak Wildlife, Mountain Goat, Sitka black-tailed deer, , , , , , , , ,

Man has introduced every mammal species on Kodiak Island other than the six endemic species (Kodiak bear, red fox, river otter, short-tailed weasel, little brown bat, and tundra vole). We humans have a sketchy history of introducing mammals into ecosystems where they did not evolve. Sometimes these introductions are harmless, but often, they are not. Ecosystems are complicated, and it is impossible for us to fully understand how the plants and animals in a particular habitat have worked together to survive over thousands of years. When we introduce mammals not native to that environment, we change the balance.

It is tricky to introduce a mammal into a habitat where it did not evolve. For example, if an island has birds that nest on the ground and man introduces an egg-eating or chick-eating predator to this habitat, the predator will soon wipe out the ground-nesting birds. Of course, most introductions do not cause such an obvious impact, but the harm is often subtle and occurs slowly over time.

New Zealanders have waged an all-out war on introduced mammals in their country. New Zealand has lost 42% of its terrestrial birds since humans settled the country 700 years ago. Many of these birds were flightless and provided easy prey for introduced mammals such as rats, stoats (weasels), and dogs. New Zealanders are trying very hard to save the few species of flightless birds they have left, including kiwis and penguins, but at this point, it is an uphill battle.

While the mammal introductions to Kodiak Island have not had the disastrous consequences of those in New Zealand, introduced mammals have had an impact on the habitat here. Beavers have altered some watersheds on the island. Their dams can divert rivers and block salmon-spawning streams. In areas where beavers are native, their activity may be beneficial to other wildlife, but in an ecosystem where beavers did not originally exist, they can have a negative effect on riparian habitat. If beavers construct a dam on a small salmon stream, they can destroy the salmon-spawning grounds in that stream.DSC_53

Mountain goats on Kodiak are over-grazing their alpine habitat, and these impacts are now being studied. Sitka black-tailed deer have nearly decimated high-bush cranberries, a species that was abundant before deer were introduced to Kodiak. Other introduced mammals have also impacted the endemic flora and fauna of the island, but most mammals were introduced in the first half of the twentieth century, and those species that survived their initial introduction, are now thriving and are considered part of the complex ecosystem of the Kodiak Island Archipelago.

Over the next few weeks, I will write about several of the introduced wild mammal species on Kodiak Island. These include Sitka black-tailed deer, mountain goats, Roosevelt elk on Afognak Island, reindeer, beavers, and snowshoe hare. I will discuss how the species are doing and how their introductions have impacted the island.

I would love to hear your comments and opinions about mammal introductions. Are they good, bad, or a little of both?