How do you FIN-gerprint a Great White Shark?
To the untrained eye, one shark fin cutting through the water probably looks like any other. Yet each great white shark dorsal fin gives our researchers and their colleagues important clues that will help to identify and protect them.
Like the swirls on a human fingerprint, the shape and notches of each white shark’s dorsal fin are unique, enabling scientists to catalog and track sharks across the oceans.
Building a Fin Photo Database
Since 1987, great white shark researchers at the aquarium, Stanford University, Point Blue, Montana State University and the University of California, Davis, have been photographing dorsal fins – first in waters off the Farallon Islands, and later at Año Nuevo Island and Tomales Point. They’ve created a photo database identifying 270 individuals over the past quarter century, providing the basis for the first-ever population estimate of adult and adolescent white sharks off the Central California coast.
This database helps scientists better understand where white sharks go and whether they return to the same waters on a regular basis. Fin IDs also help them estimate the number white sharks at these locations, and monitor the survival of individual animals.
Scientists have found that just as humans routinely travel between important locations — home, school, work — so too do great white sharks. White sharks congregate seasonally at spots along a migration route that takes them from the Central California coast, to the middle of the Pacific, and past southern California and Mexico.
Scientists use seal-shaped decoys to entice white sharks to the surface where it’s easy to photograph their fins. They also gather information such as size and sex when the sharks swim alongside their research boats. By comparing fin photos of the same sharks over the years, researchers concluded that – just as with our fingerprints, which remain the same over a lifetime – the overall shape of a shark fin remains fairly constant (with the exception of scrapes and scars).
In 2013, of the 80 individual adult white sharks photographed by researchers from the Aquarium and other institutions, nearly 65 percent had been seen in previous years. This suggests that the team is getting close to recognizing most of the adult great white sharks that frequent Central California waters.
Several have been coming back to the same waters for more than 20 years. One, a 16-foot male known as “Tom Johnson,” has been sighted for the last 26 years - the longest tracking period for any white shark on earth.
- crislaynecristina likes this
- downwhereitswetter reblogged this from montereybayaquarium
- twitchey21 reblogged this from lifeoflesley
- lifeoflesley reblogged this from hobbit-ses
- littlemissdaisybitch likes this
- bboy-kun likes this
- ifluffybug reblogged this from montereybayaquarium
- ifluffybug likes this
- temple-rabbit likes this
- butt-fuzz likes this
- escobar818 likes this
- 4coloradonatives likes this
- jadams2010 likes this
- catedrals likes this
- bitchessandunicorns reblogged this from thescienceofreality
- yeshers reblogged this from montereybayaquarium
- our-lady-of-singularities reblogged this from thescienceofreality
- riotw0lf reblogged this from thescienceofreality
- theaxrat reblogged this from werewolfmunchies
- fishapod likes this
- w0ahbr00 reblogged this from werewolfmunchies
- werewolfmunchies reblogged this from lovesick4mina
- ihavethreesettings reblogged this from thescienceofreality
- fire-flame likes this
- sfweeda likes this
- icarusandstardust likes this
- yukiru reblogged this from simplesignifier
- ripbad reblogged this from thescienceofreality
- awesomeocelot reblogged this from thescienceofreality
- sideburnz711 reblogged this from thescienceofreality
- sideburnz711 likes this
- crystenesobsessions likes this
- kyle-r reblogged this from thescienceofreality
- thepiratedragon reblogged this from thescienceofreality
- salixunit reblogged this from thescienceofreality
- salixunit likes this
- icanhascandy reblogged this from thescienceofreality
- 7locsofsamson likes this
- kkaltmayer reblogged this from thescienceofreality
- kkaltmayer likes this
- gburst reblogged this from thescienceofreality
- maura-labingi likes this
- aletheaquilianmay reblogged this from thescienceofreality
- vurige-ziel reblogged this from thescienceofreality
- mvfbattleeevee likes this
- farmingwitch likes this
- elamy reblogged this from thescienceofreality
- i-will-not-apologise-for-art likes this
- thatsgoldbaby likes this
- skyfiery reblogged this from thescienceofreality