review its proposed course of action with the Recov- 
ery Team and proceed only with the team’s endorse- 
ment. Given uncertainties concerning the effect and 
effectiveness of actions to manipulate mating behavior 
in the wild, the Commission also recommended that 
an additional behavior expert be added to the team. 
During the January 1992 Recovery Team meeting, 
the Service provided relevant background information 
and alternative research options. Based on this 
information, the team endorsed a multi-year field trial 
at Laysan Island, to begin in 1992. For the first year, 
the plan called for treating 10 male seals with the 
testosterone-suppressing drug, treating 10 others with 
a placebo, establishing a control group of 10 other 
seals, which were not to be handled, and physically 
removing up to 10 males permanently from the island. 
For 1993 the number of male seals treated will be 
determined on the basis of the number of female seals 
killed due to mobbing incidents in 1992. If one or no 
female seals are killed, 10 male seals will be treated 
in 1993. If two to seven females are killed in 1992, 
50 males will be treated in 1993. If more than eight 
females are killed, the need for alternative measures 
will be considered. A similar course of action will be 
taken for the 1994 field season, with the number of 
male seals treated and/or removed to be determined 
by the number of female seals killed in 1993. 
The team concluded that, while it would be diffi- 
cult to detect the effects of this or any other consid- 
ered approach in a clear, statistical way in the short 
term, the work should be done because of the expect- 
ed resulting increase in survival of adult females. 
During the 1992 field season the Service imple- 
mented the approach agreed upon during the Recovery 
Team meeting. The drugging experiment was carried 
out as planned; however, no seals were physically 
removed due to funding limitations. To help evaluate 
effects on the behavior of treated animals, the Service 
fitted both treated and control seals with time-depth 
recorders and collected blood samples to measure 
testosterone levels at the time the drugs were adminis- 
tered and again two to six weeks later. At the end of 
1992, field trial results were being analyzed and plans 
for further work in 1993 were being reviewed. Four 
31 
Chapter III — Species of Special Concern 
females are known to have been killed in 1992 due to 
mobbing injuries. Under the experimental design, this 
calls for 50 male seals to be treated with testosterone- 
suppressing drugs in 1993. 
With respect to adding additional behavioral 
expertise to its membership, the team concluded that 
this would be unnecessary, given expertise already on 
the team. In this regard, the Service’s 11 March 1992 
letter noted that it planned to hold a meeting of 
behavioral experts during 1992 to review all data 
relevant to male mobbing to help define future re- 
search and mitigation measures. The contemplated 
meeting did not take place, however, and at the end of 
1992 the Commission had not been advised as to 
when a meeting would take place or if it were still 
under consideration. 
Closure of the Kure Atoll LORAN Station 
In 1960 the Coast Guard established a LORAN 
navigation station on previously unoccupied Kure 
Atoll, the western-most of the Northwestern Hawaiian 
Islands. Aerial surveys at the atoll in 1958 produced 
maximum beach counts of Hawaiian monk seals well 
in excess of 100 animals, including more than 20 
pups. Given the number of animals at sea at any one 
time, beach counts of monk seals usually represent 
well under half the adult and sub-adult animals. After 
1960 the number of seals on Kure declined significant- 
ly until the mid-1980s. By that time, the total popula- 
tion at the atoll was estimated to number about 50 to 
60 animals and the number of births reached an all- 
time low of one. As noted below, the number of 
seals at Kure has increased steadily since then due to 
efforts to protect pups, introduce additional female 
pups, and reduce human disturbance. 
In 1991 the Coast Guard announced plans to close 
and dismantle the LORAN station on Kure Atoll at the 
end of 1992 and to return the island to the State of 
Hawaii. To minimize disturbance from demolition 
activities and to ensure that debris hazardous to seals 
is removed from the island, the Commission recom- 
mended in its December 1991 letter that the Service 
consult with the Coast Guard to review activities 
associated with closing the station. It also recom- 
mended that the Service place an observer on the 
