Año Nuevo is an important feeding area for one shark species.

Since the early 2000s to 2026, dedicated boat-based surveys have been conducted annually at Año Nuevo from October–February to photo-identify individual White Sharks and deploy acoustic and satellite tags. Surveys are weather-dependent and typically occur at least weekly during this period. At least one acoustic receiver has been consistently deployed throughout the entire effort period in this area, with a maximum of four receivers at any one time. The broader receiver array included many locations from the southern border of California to Washington State (Andrzejaczek et al. 2025). Residency measures were calculated for each year of an individual shark’s tag deployment period, with ‘number of days detected at a site’/365.

Año Nuevo is recognised as a feeding area for sub-adult and adult White Sharks, situated adjacent to important California Sea Lion Zalophus californianus and Northern Elephant Seal Mirounga angustirostris haul-out grounds (McHuron et al. 2018; Chinn et al. 2025; Hale et al. 2026). These prey species are present year-round with counts in the thousands, although life-stage composition varies seasonally by species, and seasonal patterns of moulting, breeding, and offshore feeding influence abundance (Lowry et al. 2017; Condit et al. 2022; Chinn et al. 2025; DP Costa unpubl. data 2026). California Sea Lions typically haul out on Año Nuevo Island, while Northern Elephant Seal colonies are present on the island and along the mainland coast. Predation events on both species are regularly observed by research teams at this site, with an estimated average of 1–2 events seen per month (BA Block et al. unpubl. data 2026), although they are challenging to document on film due to their rapid occurrence and sub-surface nature. Additionally, bite wounds consistent with White Shark predation are routinely recorded on hauled-out California Sea Lions and Northern Elephant Seals by long-term monitoring teams from the University of California Santa Cruz and the NOAA Marine Mammal Laboratory (PWR & DPC unpubl. data 2026).

The importance of Año Nuevo as a feeding area is further supported by mixing models incorporating movement and stable isotope data, which demonstrate high rates of White Sharks feeding on marine mammal prey at this coastal aggregation site, along with two other important sites at Tomales Bay and the Farallon Islands (Carlisle et al. 2012). Additionally, tagged sub-adult and adult White Sharks regularly and predictably use this area more than any other regional receiver site between mid-August to mid-February during their annual migration between the coast and offshore international waters (Jorgensen et al. 2010; Andrzejaczek et al. 2025). From 2006–2022, 355 sub-adult and adult White Sharks were tracked with acoustic tags amounting to over 760,000 detections on an extensive coastal array of receivers stretching from California to Washington (Andrzejaczek et al. 2025). Of these, 55% of detections were at Año Nuevo, with an average annual residency rate of 0.10 ± 0.10 per tagged individual in this area. The high detection rate, observed predation events, stable isotope evidence, and bite wounds on seals and sea lions show that this is a seasonally important feeding area for White Sharks.