Last week, we urged anyone that has seen a White shark in Canadian waters to please report it to the Shark Identification Network. Researchers from the Atlantic White Shark Conservancy, who are tagging White sharks off Cape Cod are trying to collect as many White shark sightings in Canadian waters as possible, to help them better understand White shark movements in the North Atlantic. We are working with them to help collect White shark sightings from Newfoundland to the Gulf of Maine.
Of course, the most important part about reporting a White shark sighting, is that it is indeed a White shark! The Atlantic White Shark Conservancy gets many reports of White sharks every year off the coast of the eastern United States, however most of these reports are actually Basking sharks, that were misidentified as White sharks. In fact, it’s not uncommon to see a photo published in a newspaper or online news site showing a “White shark” swimming close to shore with sunbathers looking on. However, upon closer inspection, the “White shark” is actually a Basking shark.
The basking shark and white shark share many similarities, such as large size and overall body shape, making identification difficult. So, how can you tell the difference between a Basking shark and a White shark?
1. Dorsal fin:
Both sharks have large, conspicuous dorsal fins but the top of the dorsal fin (apex) for a Basking shark is rounded, whereas the White shark’s dorsal fin is pointed at the apex.
2. Body characteristics
The basking shark is uniform in colour (although, sometimes has a mottled pattern) whereas the white shark has a very distinct two-toned body colour–they have a very white underside.
The gill slits of the basking shark are very large and wrap almost completely around their head, whereas the gill slits of the white shark are only at the side of their head.
Since misidentified basking sharks account for most of the reported White shark sightings that they receive, John Chisholm, of the Massachusetts Marine Fisheries Division’s Shark Research Program, made this excellent, short video on White shark identification, which clearly shows how you can distinguish the two species. Please check it out http://www.youtube.com/watch?v=1NoO7ZWJ5LE