Environment

Our Marine Environment:

What defines our local environment and ecological system is the powerful marine influence. The seas have a strong and determining effect on our weather and overall climate. They also provide the home and food supply for most of our birds, fish, and marine mammals. Even our land mammals and birds depend ultimately on the sea for most of their food supply. The seas in our area are extremely productive. This productivity is created to the north in the Bering Sea by its relative shallowness and cold nutrient-rich waters that provide abundant food for the entire marine food chain. The Gulf of Alaska, on our southerly doorstep, is enriched by upwelling of nutrient-rich waters and by the strong North Pacific Drift current bringing relatively warm waters to our shores. The map below shows the relationship of ocean currents to our area. The relatively shallow waters of the Bering Sea show up clearly on this map. False Pass is located close to the Bering Sea shelf edge which is the most productive area for commercial fishing.

Sea Ice:

Because of the strong marine influence and the proximity of the warming effects of the North Pacific Drift current to our south, Isanotski Strait seldom experiences winter conditions with sea ice. During rare very cold winters we may have fresh-water drift ice blocks coming out of the bays with the tide into Isanotski Straits. But, as can be seen in the map below, Bering Sea pack ice rarely comes as far south as Isanotski Strait and cannot enter the narrow pass entrance in any volume. This means that the Port of False Pass rarely experiences the restrictive and dangerous ice conditions that are frequent farther north that hinder vessel traffic or make it impossible altogether. Nevertheless, local ice carried by tidal currents has had damaging affects on the local wooden piling dock in False Pass on several occasions.

 

The Island Environment:
False Pass is located on Unimak Island, the first of a long chain of Aleutian Islands that extend some 1,400 miles from the tip of the Alaska Peninsula to nearly Kamchatka and Japan. Unimak is irregularly shaped and approximately 70 miles long by about 30 miles wide having 1,606 square miles in area. It is a volcanic island still in the process of growing through frequent volcanic eruptions. Present volcanic activity takes place in the middle and west portions of the island, some distance from False Pass. The variations in elevation provide for a number of special habitats for plants and animals. The size of the island and its elevation make possible rivers and streams of sufficient size to support salmon spawning grounds. Because we are an located on an island separated from the Alaska Peninsula and mainland, a few species of animals that are found on the mainland are not found here, such as the porcupine and only one moose has ever been seen. As one goes farther west to the other islands of the Aleutian Chain, the "island isolation effect" is more effective in limiting the number of animal species. Unimak is so close to the mainland that most animal species can swim the channnel. Please navigate to the City/Area Map page to see detailed topographic maps of Unimak Island and the surrounding area.