The White Shark Nursery is a heavily footage-based project and is planned to run for 3-5 years. Sharkproject Switzerland has received the unique opportunity to help fund part of this exciting research with a yearly contribution over 3 years. Sharkproject has supported one of Dr. Craig O’Connell’s projects before and we are elated to play a small part in this exciting new project.
Verein Sharkproject Switzerland
IBAN CH33 0900 0000 8547 9886 0
The Use of Advanced Baited Remote Underwater Video Systems (BRUVS) and Novel Shark Harness Cameras to Non-Invasively Characterize a Potential White Shark (Carcharodon carcharias) Nursery off Eastern Long Island, New York
Adult great white sharks are known to inhabit the waters around the northeastern United States. Despite the prevalence of adult great whites, still very little is known about the distribution or habitat use of young white sharks in this area. However, over the last several years, Dr. Craig O’Connell from O’Seas Conservation Foundation has surveyed the area around Montauk Point, New York to gather capture data from the local gillnet fisheries. These data have indicated that not only are young great white sharks perishing in these nets, but these sharks may use the area as a nursery habitat, where they live and feed until they grow and can venture into deeper waters. In 2014 Dr. O’Connell began a non-invasive research project to determine if, in fact, great white sharks use the New York Bight as nursery habitat, and to which extent they do so. The goal of his research includes determining what kind of prey are critical for the young sharks so that these species may be adequately protected from the local fishing industries.
What do young great white sharks eat?
According to previous scientific literature, the smooth dogfish shark (Mustelus canis) is not considered a key dietary item for young great white sharks. This shark species is often considered a nuisance species across the Atlantic, from Canada to southern United States. If it turns out that young great white sharks do, in fact, target these sharks as a main prey source, protecting them will become imperative to ensure neonate great white sharks continue to have access to their food source.
To tackle this question, O’Connell’s team is attempting to capture footage of these predator-prey interactions between great whites and smooth dogfish. To do so, local dogfish are equipped with harnesses that carry cameras. They are deployed into the field and resume their natural behaviors. Any attempt by a larger shark to prey on the individual is hopefully captured on film, and preliminary data have shown just that. In fact, even other shark species have been caught on camera trying to prey on these fish, which shows that the area might be important habitat for other shark species. More data will continue to be gathered but these observations support the hypothesis that dogfish are an important prey source in the area. What is most important about this study is that the smooth dogfish shark is currently an unregulated species in both commercial and recreational fisheries. Therefore, if this research illustrates that the smooth dogfish is an important food source for a variety of large shark species, fisheries managers will be notified so proper conservation measures can be put in place.
Are young sharks just passing through or are they spending time in particular areas?
For the second part of his research, O’Connell and his team are using tags and Baited Remote Underwater Video Systems (BRUVS) that are deployed around Montauk, New York. BRUVS were designed by Craig O’Connell’s team and serve as tools to observe the normal habitat use patterns of young great whites and other elmsobranchs around New York Bight. Filming began in 2016 and over the course of 3-5 years, the team will gather footage during the daytime and nighttime that can hopefully be used to identify sharks (including individuals that enter or use a specific habitat more than once), to determine the local population size, how active the sharks are during the day and at night, and finally, if this area can be categorized as a nursery habitat. The latter point could have an impact on the local fishing regulations that impact sharks, since the region that is being surveyed is highly impacted by commercial fisheries (e.g. gillnets, trawlers, and longlines). In addition, the team will collect information on water temperature, location, bait types used, water depth, etc. that will hopefully answer some long-standing questions about the habitat preferences of young great white sharks.
The team has been able to identify several different young great whites, as well as sub-adult (immature) common thresher sharks (Alopias vulpinus), adult sandbar sharks (Carcharhinus plumbeus) and juvenile dusky sharks (Carcharhinus obscurus) that also utilize the area.
The research conducted by O’Seas Conservation Foundation is likely to present a clear glimpse into the lives of young great white sharks off the coast of New York, as well as provide data that will be very useful for forming appropriate fishing guidelines that impact not just dogfish populations, but subsequently great white shark populations as well.