(
UNIVERSITY OF wasmmerh
APPLIED FISHERIES LABORATORY
FISHERIES CENTER
SEATTLE 5, WASHINGTON
January 3, 1957
Dr. Allyn H. Seymour
N NC Yy
Marine Biologist
Division of Biology and
Medicine
U.S. Atomic Energy Commission
1901 Constitution Avenue N.W.
Washington 25, D.C.
Dear Al:
Following the discussions of the recent meeting in the
offices of the Division of Biology and Medicine on the Rongelap
problem and your letter of December 4, 1956, we have reviewed
the role of crabs on the possible strontium-90 contamination.
As a result of our group thinking, we feel that the
erab-Sr9 problem is soluble and offer the following suggestions in
the hope that they will be helpful.
2.
3.
4,
The gr?° levels are high only in the land crabs.
The land hermit crab, Cenobita,
is rarely used as food
and should probably be dismissed as a hazard.
The coconut crab, Birgus, is used as food, but the population of coconut crabs on Rongelap Island is apparently
small (none have been collected there), having been
controlled by reduction of the number of animals that
could survive in the young stages because of predation
by chickens, pigs, etc.
Coconut crabs at other islands at Rongelap Atoll could
be captured and carried out to sea for disposal.
The
coconut crab is a nocturnal animal which can be
attracted to feeding stations baited with fish scrap,
coconut oil, etc. By maintaining nightly patrols of
the feeding staions for a few nights at each major
island the coconut crab population could be reduced to
an insignificant number.
5.
The land hermit crab, Cenobita, has the same levels of
activity as the coconut crab and could be used for
periodic checks to determine any possible hazard resulting from reestablishment of the coconut crab populations.
6.
Any excess of hermit crabs (Cenobita) could be collected
at feeding stations and disposed of by removal and
Sipcer yp)
IY
auren R. Donaldson
LRD:gb
7
,
4
at
AL» fiber Ff
rw
:
"£4945
wh
dumping in the open sea.
4
Jt 0 1B rector
noma +
1.