2002 Expedition Report

Between 15 July and 10 August, our research Team consisted of the following fine people:

Melissa Carp, of the New York Aquarium, NY
Paige Colwell, an EMS Technician and Firefighter from GA
Kirstin Grish, manager of a VA-based stock photo agency
Gennadyi Gurman, marine biology student at SUNY, NY
Neil Hammerschlag, marine ecology student at Nova Southeastern University, FL
Kathryn Hodgson, ecology student at St. Andrews University, Scotland
Daniel Muir, errant marine biologist and surfer from CA

We logged 15 days on the water, during which we:

Recorded 150 data points of environmental data
Scored and categorized 124 bait approaches by White Sharks
Documented and catalogued data on 91 natural predatory interactions between Cape Fur Seals and White Sharks
Observed at least 96 individual White Sharks, of which 89 were catalogued
Observed 75 breaches by White Sharks
Scored 31 social interactions between pairs of White Sharks
Documented 19 cases of natural mortality in Puffadder Shysharks
Documented 6 strikes by White Sharks on seal-shaped decoys
Documented 5 aborted predatory strikes on seabirds
Observed 3 species of whale, the rare Sub-Antarctic Fur Seal, and 9 species of seabirds

These data bring the total number of individual White Sharks catalogued to 122 individuals, including numerous resightings over separate days. Our data are beginning to show that White Sharks at Seal Island exhibit low residence times (typically, 1-3 days), strong site fidelity (going back at least 7 years), and numerous identifiable individuals appear to come and go together in stable groups of 2-6.

Further, these data bring the total number of documented predator-prey interactions between White Sharks and Cape Fur Seals to 201, of which about 35% resulted in successful kills. Recognizable individual White Sharks display distinct predatory strategies and some enjoy a predatory success rate of roughly 80%.

Perhaps most intriguingly, individual White Sharks display distinct 'personalities', such that their behavior toward baits, decoys, the boat, the cage (with or without divers inside), and each other is readily predictable to a high degree of accuracy. The overall rate of agonistic (threatening) interactions among them is very low, suggesting dominance hierarchies in which social rank is established and stable over time.

Cumulatively, the data from Seal Island now affords sufficient data for at least 16 scientific papers for peer-reviewed journals and have created opportunities for two of this year's Expedition participants to extend aspects of this on-going study (under the aegis of the ReefQuest Shark Research Program) toward their graduate degrees.

Overall, it was a spectacularly successful field season. Who knows what we will discover next year?

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