Shark Predation on Hawaiian Monk Seals - Pacific Islands Fisheries ...

Plans developed but not executed in 2009 include:
Creation of a protocol for the limited removal of Galapagos sharks in the vicinity of
pupping sites.
Creation of a protocol for the expanded removal of Galapagos sharks at FFS.
Collection of preliminary information on barrier design.
Actions Taken in 2009: Translocations, <strong>Shark</strong> Tagging, Remote Camera Installation, Seal
and <strong>Shark</strong> Behavior Studies, Comparison of Deterrent Treatments
The number of pups born at FFS this season was the lowest on record at just 31 individuals (as
of August 19, 2009). Field staff directly observed sharks patrolling pup sites on 13 different
days, 3 of which concluded in attacks. In all, 4 pups suffered shark bites, of which 2
subsequently died within a few weeks. The remaining 2 are not expected to survive long based
on the severity of their wounds. An additional 5 pups disappeared, 3 of which can be inferred
as shark caused.
Translocations of newly weaned pups continued with 14 pups moved from Trig, Gin, Round,
and East to Tern Island. HMSRP deems translocation a valuable tool in boosting pup
survivorship and recommends its continuance. Preweaned pups are a primary target of sharks
but not candidates for translocation because their nursing and bonding requirements preclude
action by HMSRP to move them to safer areas. Thus, additional actions that protect younger
pups are required.
Several of the actions executed in 2009 aim to inform the “small subset” premise. First, the
acoustic tagging study lead by Carl Meyer (HIMB) aimed to tag Galapagos sharks across the
three habitat types to determine their movement across the atoll for the life of the tags
(approximately 2 years). One hundred and eighty-nine sets were made with 1570 hooks
yielding 6850 hook hours; 68 Galapagos sharks and 40 tiger sharks were sonic tagged between
May and August 2009. Additional sharks were spaghetti tagged. Analysis of this data will help
determine the percentage of tagged sharks that frequent the pupping sites when pups are
present. Partial-analysis is expected to be available in 2010 and a more complete analysis in
2011.
Second, a remote camera system was installed at Trig Island by HMSRP to capture shark
activity in the sector (2E) that showed the most nursing pups on the beach and shark activity in
the nearshore water. The estimated visual range of the cameras was a maximum of 120 m in
optimal light conditions to the south and east (sand beams blocked views to the west). Analysis
of video footage will help determine shark species, frequency of visits, and times (between
0530 and 1900 hours) of greatest activity. Video viewing and cataloguing of data are currently
under way. Video footage viewed of data reveals additional Galapagos shark sightings and
attacks on pups.
Third, field staff camped on Trig and Gin Islands for several weeks across the season to
directly observe and systematically record shark behavior, mother-pup-shark interactions and
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