LAND CRABS AND RADIOACTIVE FALLOUT AT
ENIWETOK ATOLL
Introduction
Periodic studies of the effects of the atomic testing
program on the biota of the Marshall Islands have been made by
the staff of the Applied Fisheries Laboratory, University of
Washington, since 19462713 During the 1954 testing program at
Eniwetok a continuous biological survey was initiated.
In this
rerort the portion of the survey concerned with the uptake of
radionuclides by the land hermit crab, Coenobita perlatus Edw. Tt,
is presented.
Results of possitle ecological and physiological
significance in the movement of strontium and cesium through the
food cycle have been obtained.
Strontium-90 concentration in the
land crab skeleton may be a sensitive index of biologically aailable radiostrontium in the environment.
Coenobita is an omnivorous scavenger which feeds primarily
on land plants and on detritus washed up on the beaches.
primarily nocturnal and
spends the daylight
hours
It
is
hidden in
shrubs or under debris.
The crabs were taken from Belle (Bogombogo) Island which lies
2.3 nautical miles southwest of the site of the Mike test of 1952
and the Nectar test of 1954.
This itsland is downwind from the
site of these tests.
Prior to the Mike test Belle Island had a covering of shrubs,
* We are grateful to Dr. C.H. Edmondson, Bernice P. Bishop Museum,
Honolulu, Hawaii, for identification of the species.
~1-
pet