By Ali (guest blogger)
Science is awesome. Sharks are awesome. And, when you combine the two, you get this!
I’ve been following this research group called OSEARCH for a while now and they do some pretty wild things. Including tagging and releasing Great White Sharks or White Pointers like Amy (pictured above). See OSEARCH’s Global shark tracker here or follow on facebook. There are a lot of unexplained mysteries when it comes to white pointers. Until recently, very little was known about migratory patterns, where and when they breed, and their general behavior. OSEARCH has provided the means for marine scientist to go beyond traditional methods of obtaining data on apex predators. Through direct on-deck observations, as well as tagging and satellite tracking systems, our understanding of the biology and behavior of these sharks has skyrocketed. Check out this great news broadcast that describes OSEARCH’s work.
A paper released this year (Domeir and Nasby-Lucas 2013) has investigated the migratory patterns of 4 adult female white pointers (using the satellite tagging programs made possible by OSEARCH) and found distinct seasonal migration patterns for northeastern Pacific white sharks. Their findings show these female sharks have a 2-year long migration course, compared to the male’s 1-year migration. It is speculated that female gestation lasts for about 18 months and they spend much of this time offshore. Interestingly, the preferred prey for these pregnant females is unknown, although both male and female migratory paths overlap with three species of spawning squid and sperm whales, but no small marine mammals, suggesting unique feeding regimens (see here Mega Shark vs Giant Octopus, for Hollywood dramatization).
On top of what little we actually know about these astounding creatures, shark populations are declining in many parts of the world, with 30% of species threatened or near-threatened with extinction. It is difficult to build conservation and management strategies when so little is known about the sharks themselves or what is causing their decline in numbers. OSEARCH’s groundbreaking research will help scientists to discover more about these beautiful creatures and will help to protect one of the planets most revered apex predators.