Komandorsky National Natural Reserve
The Commander Islands, which are the last in the Aleutian Island chain, were formed in by underwater eruptions and the subsequent raising of the ocean bed in the region of a tectonic fault. Proof of their volcanic origin is provided by the presence spherical and ellipsoidal lava structures, which were long ago spewed out by underwater eruptions. Two such outlets of lava above the surface of the ocean can be found on Medny Island by the Gladkovskaya and Zhirovaya bays. Strata of a much later eruption form the body of the islands and can be observed in the eroded, precipitous cliffs.
There are about 5,000 sea lions on the Commander Islands. The main herd of this large animal of the family of eared seals keeps to Medny Island. The adult bull weighs over a ton, and the female up to 300 kilogram's. Sea lions choose the same kind of places for their rookeries as seals. Frequently sea lions occupy the territory of the fur seals, but usually they settle further away from the shore line. They feed on fish, squid and octopus.
Fur seals feed mainly on fish, squid and other cephalopods. Salmon is almost entirely absent from their diet. As with sea lions, there is a great difference between the adult bulls, which weigh up to 250 kilograms, and the females whose weight is only about 60 kilograms. Life in the fur seal rookeries is fascinating, and one can observe it for hours day after day. In all their movements the fur seals are extraordinarily agile and graceful.
The majestic poses and the sheer power and strength of the bulls and their aggressiveness serve to stress by contrast the grace of the diminutive females and their offspring. These magnificent animals live according to their own laws, and the apparent fussing about and lack of order in their behavior have a method of their own. During the most tense period, when harems are being formed, the bulls are extremely restless, and those keeping watch over their own groups of females are apt to fight. The milk of the cows is highly nourishing and contains up to 50 per cent fat. After feeding her young the female seal goes out to sea and may be away for a whole week. Meanwhile the black baby seals stay in the special areas allotted to the young, where they gather in hundreds away from the quarreling and fighting of the adults. Baby seals sleep packed close to one another or restlessly and aimlessly shift from one place to another, constantly bleating like sheep. When the mother returns from the sea she calls out for her pup before she reaches land and thousands answer her from all parts of the rookery.
Nevertheless each female unerringly recognize her own offspring by its voice. As time goes on the character and the behavior of the adult bulls and cows change. They become easily scared. Even the most aggressive and bad-tempered of the bulls retreat before the approaching human beings. This is the time when the growing youngsters learn to swim and catch fish close to the shore and among half-submerged rocks. In late autumn the young animals accompany the adults on the long and dangerous route to the south. Water is the native element of the fur seals, who come ashore only for breeding. They move awkwardly on their flippers to the sea, straining towards it with their highly streamlined body, and the first movement in the water is like a sigh of relief - light, joyful, and abandoned. Towards the end of November the rookeries became deserted. It is still a mystery how the fur seals find their way across vast seas and oceans, and how they manage to get back again.
Sea otters are peaceful animals, and make loving and courageous parents. The life of the animal is entirely bound up with the sea. Unlike aquatic animals which are protected by a subcutaneous layer of fat the sea otter relies on its fur for insulation. If the fur gets soaked through the sea otter dies from cold. The sea otter feeds on sea urchin, fish, shellfish and octopus.