Since 2001, HMSRP translocated newly weaned pups from islets with intense shark activity to Gin, East, and Tern Islets. However, predati<strong>on</strong> was later detected at Gin and East, so the majority of translocati<strong>on</strong>s c<strong>on</strong>tinued to occur at Tern, an island with a historically low number of incidents (NMFS, unpubl. data). Translocating pups at the weaning stage represented the first available opportunity for moving them to safe areas so as to not disrupt the mother-pup b<strong>on</strong>d and nursing interacti<strong>on</strong>s. Translocati<strong>on</strong> removed weaned pups from the highest risk areas. As a result, pups remaining at unsafe sites (i.e., Trig Island) became the <strong>on</strong>ly available targets of shark predati<strong>on</strong> by default. Thus, preweaned pups and newly weaned (within the first few hours of weaning) were not protected through translocati<strong>on</strong>. A trial of four deterrents and devices was c<strong>on</strong>ducted in 2008 and fully reviewed in Secti<strong>on</strong> I of this memorandum. In brief, ceramic magnets and electromagnetic deterrents (<str<strong>on</strong>g>Shark</str<strong>on</strong>g> Shields), as well as a visual device (moored boat) and auditory device (boat noise), were simultaneously deployed at Trig Island. Four shark incidents occurred <strong>on</strong> a cohort of 16 pups in 2008. The efficacy of these deterrents and devices to prevent shark predati<strong>on</strong> was equivocal, in part, because of the low sample size and the study design but also to the fact that a few shark incidents did occur during the period that some of the deterrents and devices were operating. In November 2008, the impact z<strong>on</strong>es of two <str<strong>on</strong>g>Shark</str<strong>on</strong>g> Shields were tested at two locati<strong>on</strong>s approximately 3 miles offshore in Haleiwa, Hawaii <strong>on</strong> 4 free-ranging Galapagos sharks. <str<strong>on</strong>g>Shark</str<strong>on</strong>g>s were first baited in with fresh squid, and feeding behavior was observed. After approximately 5 minutes, a <str<strong>on</strong>g>Shark</str<strong>on</strong>g> Shield was deployed from the side of a small 17-foot boat in the vicinity of the bait. Galapagos sharks c<strong>on</strong>tinued to feed and appeared to be deterred at a distance of approximately 1 m; they either avoided (quick turn away) or did not approach the bait in the 1 m z<strong>on</strong>e. This diminished impact z<strong>on</strong>e as compared to the manufacturer’s claims suggests that the units functi<strong>on</strong> as a point deterrent rather than an area deterrent and are likely not effective across the large areas. Intensive hazing and harassing of Galapagos sharks to deter them from pupping sites, especially Trig Islet, was implemented in 1998 (in the form of spaghetti tagging) and 2001 through 2004 (intenti<strong>on</strong>al harassment) (NMFS, 2003; NMFS, 2004; NMFS, 2005; NMFS, unpubl. data). The rate of shark predati<strong>on</strong> events was significantly reduced after harassment events were initiated in 2001. Small sample sizes and the exclusi<strong>on</strong> of significant covariates (i.e., pup density and shark culling) in this analysis should be c<strong>on</strong>sidered in the interpretati<strong>on</strong> of this result (Hayes, 2002). Small-scale culling operati<strong>on</strong>s to remove Galapagos sharks were initiated in 2000 and c<strong>on</strong>tinued each year thereafter until 2007. A total of 12 Galapagos sharks were removed from 2000 to 2006 (1 shark in 2000, 5 sharks in 2002, 2 sharks each in 2003, 2004 and 2006; no sharks were removed in 2001, 2005 and 2007) (Hawn, 2000; Hayes, 2002; NMFS, 2003; NMFS, 2004; NMFS, 2005; Harting et al., in prep.). Methods included harpo<strong>on</strong>ing and fishing with handlines and drumlines in shallow waters primarily near Trig. CPUE was exceedingly low and appeared to decrease each successive seas<strong>on</strong> (NMFS, unpubl. data). In July and October 1999, more than 50 Galapagos sharks were removed from FFS by commercial fishers, partially operating in the deep lago<strong>on</strong>al area of the atoll (NMFS, unpubl. data; Vatter, 2003). These 1999 removals and the 2000 removal of 1 Galapagos shark by HMSRP was associated 32
with the greatest drop in preweaned pup losses to shark predati<strong>on</strong> to date, from 22 pups killed in 1999 to 8 pups killed in 2000 (Fig. 4). 33
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