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COMPTUEX/JTFEX EA/OEA Final Appendix ANorthern elephant seals molt, breed, and give birth primarily on offshore islands off Baja California andCalifornia. Rookeries are found as far north as the South Farallon Islands and Point Reyes (Barlow et al.,1993). The California population is demographically isolated from the Baja California population, and isconsidered a separate stock, although genetically the two populations are indistinguishable (Barlow et al.,1997). About two thirds of the California population hauls out on San Miguel Island, about 32% on SanNicolas Island, and the remaining seals use Santa Rosa (1%), Santa Cruz, Anacapa, Santa Barbara, andSan Clemente islands (Bonnell and Dailey, 1993; U.S. Navy, 1998; Carretta et al., 2000).Table A-7. Seasonal Activities of Pinnipeds in and Near the SOCAL Range ComplexJan Feb Mar Apr May Jun Jul Aug Sep Oct Nov DecHarbor Sealadult males B M Madult females N B N N M Mpups N N Njuveniles M MNorthern elephant sealadult males B B M M Madult females B N B N M N M M Npups N N N Njuveniles M M MCalifornia sea lionadult males B B Badult females N B N B N B N N M N N Npups N N N N N N N NjuvenilesGreen indicates not in complex, Yellow indicates found in the complex at sea and hauled out periodically, but not engaged insensitive activities, and Red indicates found in the complex at sea and hauled out for prolonged periods engaged in sensitiveactivities: M = molting, B = Breeding, N = Nursing.They haul out on land to give birth and breed from December through March, and pups remain hauled outthrough April (Fig. A-23). After spending time at sea to feed (post-breeding migration), they generallyreturn to the same areas to molt (Odell 1974; Stewart and Yochem 1984; Stewart 1989; Stewart andDeLong 1995). However, they do not necessarily return to the same beach. . Adult males tend to haulout to molt between June and August (peaking in July), whereas females and juveniles haul out to mostbetween March and May (peaking in April).For much of the year, northern elephant seals feed mostly in deep, offshore waters, and their foragingrange extends thousands of kilometers offshore from the breeding range into the eastern and central NorthPacific (Stewart and DeLong 1995; Stewart 1997; Le Bouef et al. 2000). Adult males and femalessegregate while foraging and migrating; females mostly range west to about 173°W, between the latitudesof 40°N and 45°N, whereas males range further north into the Gulf of Alaska and along the AleutianIslands, to between 47°N and 58°N (Stewart and Huber 1993; Stewart and DeLong 1995; Le Bouef et al.2000). Both sexes routinely dive deep (492–2,625 ft [150–800 m]) (Le Boeuf et al. 2000); dives average15–25 min, depending on time of year, and surface intervals between dives are 2–3 min. The deepestdives recorded for both sexes are over 5,000 ft (1,524 m) (e.g., Le Boeuf et al. 2000; Williams et al. 2000;Schreer et al. 2001). Females remain submerged ~86–92% of the time and males ~88–90% (Le Boeuf etal. 1988; Stewart and DeLong 1993, 1995). Feeding juvenile northern elephant seals dive for slightlyshorter periods (13–18 min), but they dive to similar depths (980–1,500 ft [300–450 m]) and spend asimilar proportion (86–92%) of their time submerged (Le Boeuf et al. 1996).A-51 February 2007