Right, so now that I've been here for almost 2 months, I feel like it's a little strange that I haven't done a post on the one shark I work with pretty much every day. So without further ado, I bring you the lemon shark.
Lemon sharks are the reason the Bimini Biological Field Station exists. The man who founded the lab, Dr. Samuel Gruber, has dedicated his life to understanding these sharks. Right now, we have a Phd. student at the lab conducting her research on juvenile lemon sharks to see how they are affected by the destruction of nursery habitat on Bimini island. Almost everything we do is gathering data for her project.
(Note, the resort called Bimini Bay is kind of the bad guy in all this, but it isn't so simple. The project has brought a lot of jobs to the island but at the same time has destroyed valuable mangrove habitats that the lemon sharks and many other marine species use as a home. That is what Kristine's project is all about. What's worse is that the owners of the resort cleared off more land than they could afford to develop in an attempt to attract investors. Basically they bulldozed about 2 square miles of mangrove forests for no reason other than to make it seem like they were making progress. Boo them, but do it quietly because Bimini needs the jobs. Anyways...)
So about the lemon shark...They can grow up to 13 feet long, but generally top out at about 10 feet. The ones you see in these pictures are juveniles, no bigger than about 2-3 feet long. That being said, these kids are STRONG. The second day at the lab, we had a half-day class devoted to how to handle juvenile lemon sharks. They are fast, strong, and can pack a mean bite if you don't respect them. Lemon sharks are set apart from other sharks in a few ways. First, they can pump water through their gills without swimming, allowing them to breathe without moving. (If you recall, tiger sharks and nurse sharks also share this ability.) Another defining characteristic is that the first and second dorsal fins (the ones on top, in case you forgot) are almost the same size. In most sharks, the second dorsal is significantly smaller then the first.
The way to hold them is just behind the gills but in front of the first dorsal fin. Lemons are extremely flexible, so if you try to hold them anywhere behind the first dorsal, they can whip around and grab on to you.
Here at the lab, we have a bunch of different tasks to perform involving baby lemon sharks; too many for just one post. From here on out, I'm going to try to do a post a week describing the different things we do to study the sharks. Originally I thought this would be too boring for most people, but nothing terribly awsome is happening so I want to put something up. I'll start with tracking, and then move to pen trials, seining, and then eversions (you pull a sharks stomach out through its mouth to see what it has been eating...SO cool.) I have pictures for tracking, but not enough for seining and eversions, hence the weekly posts and not daily. That will bring us to the end of March when mini-PIT happens, and that's an entity unto itself. So until tracking day next week, adieu.
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