Vol. 53 - Alaska Resources Library and Information Services

2. Larval crustaceans are more sensitive to any group of pollutants
(including oil) than are juvenile or adult stages (Armstrong et al.
1976; Johnson 1977).
3. Larvae grow rapidly in the water column and molt up to five times
in three to four months, whereas adults molt only once annually.
Molting is the physiological event in crustacean life cycles most
sensitive to ambient perturbations such as oil pollution.
During
an oil mishap, larvae will be exposed for a greater portion of
their abbreviated molt cycle than will adults.
4. Recruitment of legal crabs to a fishery may be largely dependent on
the larval survival of a given year-class (McKelvey et al. 1980;
Somerton 1981).
Annual variations of high or low abundance indicate
differential mortality caused by physical and biological factors
that vary in intensity and effect year to year (Incze 1983).
Extensive oil pollution in critical seasons could increase larval
mortality in years when natural causes are relatively benign, or
act synergistically with severe natural events to decimate larval
cohorts and, in turn, curtail the fishery years later.
1.2 The Data Base
Zooplankton samples sorted for this study of larval decapod distribution
and abundance have come from several collections made in different
years and areas with varying degrees of temporal/spatial thoroughness
and continuity (Section 2.0, Methods and Materials, gives details
of the data base).
Only in the years 1980 and 1981 (and to a limited
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