Identifying diurnal foraging habitat of endangered Hawaiian monk seals using a seal-mounted video camera

The Hawaiian monk seal (Monachus schauinslandi) is thought to be a foraging generalist, preying on numerous species in diverse habitats of the subtrop ical Northwestern Hawaiian Islands. Ac che atoll of French Frigate Shoals, recent evidence of emaciation and low survival in monk seals prompted a sea rch for their specific prey communities and foraging habitat. A video camera (National Geographic Television's CRITTERCAM) fitted to 24 a dult male seals documented benthic and demersal foraging on the deep slopes (50-80 m) of the atoll and neighboring banks. The number of bottom searche s for prey was compared by year, time of day, type of bottom, individual se al, and length of bottom time. Analysis of variance identified a significan t interaction of seal and bottom type, explaining 65% of the coral variance . Seals fed on communities of cryptic fauna (fish and large invertebrates) in transitional "ecotone" regions of low relief where consolidated substrat e, rubble, and talus bordered areas of sand. Independent areal surveys of b ottom types throughout the atoll and neighboring banks suggest that the typ e of bottom selected as foraging habitat represents a relatively small perc entage of the total benthic area available.