Posted on 07/04/2021 11:48:42 AM PDT by Capt. Tom
White Shark Research
Sharks in New England The Northwest Atlantic Ocean is home to a variety of marine species, and sharks are no exception. From the large filter-feeding basking shark to the small bottom-dwelling spiny dogfish, sharks of all shapes and sizes can be found inhabiting the waters of New England. Perhaps the most notorious and charismatic of these fishes, however, is the white shark.
White sharks are classified as a highly migratory species, traveling large distances in search of optimal foraging and mating opportunities. Their presence in New England is historically documented, and they are most often observed during late spring, summer, and fall months. White sharks are considered an apex predator of their ecosystems, meaning they exist at the top of the food web with few predators. Young white sharks predominantly prey on bony fish, but as they grow and mature, the primary source of food transitions to marine mammals.
Concerning their populations, the management of white sharks in the Northwestern Atlantic could be considered a conservation success story. Research suggests that abundance has increased following the implementation of conservation measures in the 1990’s, and protection of marine mammals in the 1970’s has resulted in recovery of seal populations, which are a major prey of white sharks. However, according to the International Union for the Conservation of Nature (IUCN), as of 2019 the white shark remains a globally vulnerable species, threatened by fishing and harvesting in parts of the world.
This summer, Maine DMR has unveiled a new resource for people on the water or on the shore to confirm if what they see is a white shark. A form is now available online, that provides a convenient way to submit photos and a description of what you see to the Maine DMR science bureau. Visit here for more information and a link to the form.
Ongoing Research and Collaboration In 2020, the Maine Department of Marine Resources, in collaboration with Massachusetts Division of Marine Fisheries, the Atlantic White Shark Conservancy, and James Sulikowski of Arizona State University, initiated efforts to monitor the presence of white sharks in southern Maine waters. With the placement of acoustic monitoring devices (or “receivers”), which record signals from acoustic transmitters (or “tags”) attached to sharks by researchers outside the DMR, the DMR and its collaborators monitored trends in coastal shark activity. Results from this preliminary survey are being used to expand the survey’s scope in 2021. As of June this year, DMR has successfully deployed 32 passive acoustic receivers across southern and Midcoast Maine.
To further improve the management and scientific knowledge of white sharks in the Northern Atlantic, Maine DMR has partnered with several regional organizations to form the New England White Shark Research Consortium (NEWSRC). With access to a large variety of resources and knowledge, the DMR and NEWSRC aims to further our understanding of white shark ecology, distribution, and habitat use.
Members of the NEWSRC include: Atlantic Shark Institute, Atlantic White Shark Conservancy, Center for Coastal Studies, Canada Fisheries and Oceans, Massachusetts Division of Marine Fisheries, New England Aquarium, New Hampshire Department of Natural and Cultural Resources, National Oceanic and Atmospheric Administration Apex Predators Program, Rhode Island Department of Environmental Management and Division of Marine Fisheries, Sulikowski Shark Lab of Arizona State University, University of Maine, Bigelow Laboratory, University of Massachusetts (Amherst and Dartmouth), and University of New Hampshire.
The department deployed 11 receivers between Wells and Popham Beach State Park in 2020.
All sites were chosen to ensure that data supports efforts to protect public safety and to provide important information about migration and habitat use of great white sharks in the Gulf of Maine.
Receivers deployed in 2020 were retrieved in the fall and data was downloaded by DMR Science Bureau staff. It has been shared wit the New England White Shark Research Consortium, which will incorporate it into its ongoing research.
Data from the acoustic receivers has been uploaded to the Atlantic White Shark Conservancy Sharktivity app. The app provides users with a recap of shark activity detected by receivers, in addition to shark sightings information and alerts. The app also allows users to upload their own photos and locations of sharks they spot. Information and app downloads can be found at https://www.atlanticwhiteshark.org/sharktivity-app.
2020 Acoustic Receiver Array Details
Receivers deployed: 11
Depths range: 27’ to 55’
Total fish detected: 45
Non-shark fish: 29
Total transmitter pings: 20,244
Non-shark pings: 19,000+
Shark Species Observed
White Shark (Carcharodon carcharias): 14
Blue Shark (Prionace glauca): one
Sand Tiger Shark (Carcharhinus taurus): one
Detection Highlights
Earliest detection: “Lockjaw” on Jul 25th at Stratton Island-- Latest detection: “White Shark 2020_07” on Nov 8th at Wells-- Largest shark: “Gillie” – 15’ female white shark tagged in 2015-- Smallest shark: unnamed 4.5’ female white shark tagged in 2017-- Sharks detected by two or more receivers: “Joanie”, “Salty”, “White Shark 2020_07”, and one unnamed-- Most mobile shark: “White Shark 2020_07” - detected at six receivers from Aug 20th (Popham) to Nov 8th (Wells)-- Most active months: August (seven white sharks) September (five white sharks, one blue shark)-- Most active receivers: Bailey’s Island (four white sharks) and north Wood Island north (four white sharks, one blue shark)--
Plans for 2021
Maine DMR has deployed 32 acoustic receivers in 2021 in collaboration with partners in the New England White Shark Research Consortium. The receivers will continually log and store data until they are retrieved and data is downloaded. DMR plans to retrieve the receivers and download data at least once during 2021 and again when they are pulled for the winter.
Acknowledgements
The receiver array was made possible in 2020 thanks to members of the New England White Shark Research Consortium, with special thanks to Massachusetts Division of Marine Fisheries, Atlantic White Shark Conservancy, and the Sulikowski lab. Transmitters detected by this array originate from regional collaborators both within and outside the consortium.
About the New England White Shark Research Consortium
Maine DMR, in collaboration with members of the New England White Shark Research Consortium, aims to characterize the presence and habitat use of white sharks in coastal Maine waters. Established in 2020, the consortium continues to expand its monitoring coverage within the northern Gulf of Maine and throughout the region.
This is a long read for Freepers, but for those interested we are now into July and shark happenings will start to ratchet up now, and be coming into the news.-Tom
There’s so much we can learn from Great White Sharks (Biteus Inhalfus).
Hahahahahahahahaha! You really did make me LOL when I read that-never heard that before, and it whacked me square across the funny bone!
Nicely done!
Interesting.
OT
The 19,000+ non-shark pings...stripers, cod and tuna?
(although it seems rather skinny water for tuna)
Since the pings come from the acoustic tags, Biologists will place them on many species including stripers,cod,tuna different shark species etc. even on horseshoe crabs.
Years ago in Plymouth Mass. a biologist friend did a long term study and would catch sandtiger sharks flip them up side down ,cut them open and place an acoustic device inside, and stitch the cut closed and release the shark.
In the Carolinas he would get regular ping reports from biologists there,, and realized the hydrophones along the east coast between Massachusetts and the Carolinas were not reporting ping information because the biologists were only interested in their own species study. They couldn't care less about somebody else's study.
When he got involved with the white shark tagging, he noticed the same thing-unreported white shark pings. He pleasantly and diplomatically, got many of the biologists from Canada to Florida to report the white shark pings on their hydrophones.
So he has to deal with 2 species-white sharks, and other biologists. - Tom
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