ALASKA FOR YOUR INFORMATION
THE SEAOTTfER
PART I
The primary management aim of the Refuge is management of the sea otter pop
ulations as a fur resource, with an annual harvestable surplus of animals the
ultimate objective* This can be expected in some parts of the Refuge-in the
near future; these parts being in the areas where a saturated population of
otters in now considered to exist. In other areas where the animals were wholly
exterminated and today remain isolated by wide and in some cases deep passes
from existing populations, artificial reintrodubtion of live sea otters will be
an intermediate step to a harvestable surplus.
Originally the entire area comprising the present Refuge was inhabited by
sea otters but this is not true at present. Many of the areas where the otters
has been exterminated are being- naturally restocked by remnant populations that
survived extinction in adjacent areas. At present the greatest concentration
of sea otters in the Refuge (and on earth) is in the 250 mile long strip lying
almost equally divided on either side of the 180th Meridian. This is the area
from Adak to Kiska. ’In-expanding, this large population of sea otters'is re
establishing the animals in waters accessible across-ihe relatively narrow pass
es from the Tahaga and Kanaga eastward, but from Kiska westward to the Near
Islands the passes ard wide; and in the central Aleutians, between Amlia and
Umnak there are more Wide passes. 1$ is in these areas, isolated as they are
by wide passes, that artificial1 restocking wili be necessary.
The Fish and Wildlifer‘Service has been engaged in research with captive ani
mals since 1951. In 1:954‘the first real ‘measure of. success was achieved by
keeping three young sea otters alive as captives for approximately three months.
These three were,successfully moved, first from ^mchitka to Adak,< where they
remained for nearly six weeks, then to Seattle for. two weeks, and finally on to
Washington, D.,C. There.they were delivered to the National Zoological gardens
but died shortly after arrival. Since then the study ef captive mortality has
been carried much further, an'dirr 1958 it was possible, to maintain animals alive
with rejalive ease near the point of capture. The. problem of transporting them
with a reasonable degree of success has yet to be solved.
The sea otter is a marine'mammal that bdars the. world's most valued fur. , An
adult male may* achieve a length of between five and . six feet and a weight of
approximately 80 pounds.' A -female, though a very.nearlythe same length, weighs
approximately one 'third less. The legs are short, hind, paws are webbed and
greatly enlarged with the fore paws proportionally cma.ll. and not webbed. The
animal is not well 'Suited for movement on*land, consequently its terrestrial
existence is normally limited' to off-shore rocks and islets, and the area with
in a few feet of‘the shore line on larger islands. Outside the .Refuge a sea
otter is rarely observed ashore on mainland areas. The animal Is poorly
suited for its existence in water as marine mammals go and is not so capable of
overtaking fish as its near relatives, the mink and . j^and otter. Most of the
fishes it can capture are the tyno that hide., .rather than flee. • Its'fcsod con
sists principally of more or less sessile marine invertebrates, of which the
green sea urchin (stronqvlccsntrcucus droebachiensis) is the most important. To
this diet are added, among other less important items, rock oysters, clams,
mussels, chitons, snails, and related molluscs, crabs, and such fishes as can
be caught. This diet limits the sea otter to relatively shallow areas, they
are known to dive for food in 26*fathom depths and are probably capable of
slightly more. •••• . ■ *