Granite Canyon
Survey of Southward Migrating Gray Whales 
SWFSC scientists conduct shore-based surveys for southbound gray whales from Granite Canyon Marine Laboratory, located on the Big Sur coast about 8 miles south of Carmel, CA. The sighting data, collected in collaboration with scientists from NOAA Fisheries Service's Alaska Fisheries Science Center, are used to estimate the abundance of the eastern north Pacific gray whale. Although it was removed from the US Endangered Species List in 1994, the eastern north Pacific gray whale remains vulnerable to a variety of threats, including climate change.
 This project, along with the SWFSC survey of northbound gray whales and analyses of ice distribution information from the Arctic, enables us to study the link between reproduction in this population and inter-annual climate variability in the Arctic where these whales feed in the summer months. This work has the potential to shed light on important questions about the impacts of climate change on Arctic ecosystems, and on gray whales and other species that depend on these ecosystems for their survival.
Contacts: Wayne Perryman and Aimée Lang
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Piedras Blancas
Survey of Northward Migrating Gray Whales
The northbound migration is composed of two distinct pulses of whales. The first is composed of adults and juveniles, and the second is made up almost entirely of cows with their three month old calves. Since the spring of 1994, scientists from the Southwest Fisheries Science Center have been monitoring this northbound migration of cows and calves from Piedras Blancas, a point of land just north of San Simeon, California and just south of the Big Sur coast. This site is ideal for counting these whales because these animals generally pass within 200 m of the point and often stop to nurse their young in the lee of the rocky point.
Counts of northbound cows and calves have revealed surprising variability in calf production for this population. See estimates of gray whale calf abundance from 1994-2006. It appears that the number of calves born each year is related to environmental conditions in the Arctic that limit prey populations and/or the availability of prey to reproductive females. We have hypothesized that the timing of the melt of sea ice in the Arctic may control access to primary feeding grounds for newly pregnant females and thus impact the probability that existing pregnancies will be carried to term.
Contact: Wayne Perryman
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