Who’s who?

Posted by on Aug 28, 2012 in Sighting Updates | 5 Comments

Individual basking sharks can be identified from photographs of their dorsal fins.  This technique is called photo-identification and has been used to distinguish individuals of other species, such as humpback whales, right whales and sperm whales.

How does photo-ID for basking sharks work?

  • The shape of the dorsal fin, colouration patterns, presence of scars and location of nicks and notches are unique to each basking shark
  • Photographs of the dorsal fin are taken each time we spot a shark and entered into a database that includes information such as date, time and location of sighting
  • Each photograph of an individual is given an identification number.
  • All new photographs can be compared to existing photographs to see if we have a match
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Dorsal fin of a basking shark showing nicks and notches on the trailing edge

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Dorsal fin of a basking shark showing scars

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Different shapes of basking shark dorsal fins

Some things we can learn about basking sharks in the Bay of Fundy using photo-ID include:

  • With enough photos of individual sharks, we can estimate population size in the Bay of Fundy
  • We can determine whether the same sharks return to the Bay of Fundy year after year
  • We can examine how individual sharks use the Bay of Fundy within a season; maybe a shark is spotted off Brier, N.S and two weeks later is spotted off Grand Manan, N.B.

We are currently developing our basking shark photo ID catalogue. If you have any photographs of basking sharks, please submit them to our database here. The more photographs we have, the better!!

5 Comments

  1. Eagle eyes | Fundy Sharks
    October 13, 2012

    […] of Fundy since the 1990′s. We’re in the process of scanning her old slides to add to our basking shark photo ID catalogue. Below, are a some of the individuals Laurie has photographed in more recent years. Individual […]

    Reply
  2. Matchmaker | Fundy Sharks
    October 28, 2012

    […] Science Horizon intern, Lisa Hoogenboom, has been working hard on our Basking Shark Photo ID Catalogue. She just finished cataloguing all our existing basking shark photos that were taken from 1992 to […]

    Reply
  3. Take Two | Fundy Sharks
    November 15, 2012

    […] weeks ago we told you about about a match we made from our Basking Shark Photo ID Catalogue of an individual that was photographed 3 years apart. Here is another match we […]

    Reply
  4. We’re expanding! | Fundy Sharks
    June 21, 2013

    […] heard that we’ve received some Habitat Stewardship Funding (HSP) to expand our Bay of Fundy Basking Shark Photo ID Catalogue and Shark Sighting Database to the Eastern seaboard: from the Gulf of Maine up to Newfoundland! And […]

    Reply
  5. Back in the Bay | Fundy Sharks
    July 7, 2013

    […] haven’t had a chance to compare this individual to the others in our photo ID catalogue, but in the meantime, have a look at this shark’s dorsal […]

    Reply

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