Tuesday, October 14, 2014

Turtle Tuesday #6

I skipped last week again, sorry guys!

This post is going to stray away from turtles, because I strayed away from turtles this past week! This past Thursday, I went out with the lemon shark team! We released a few of the sharks they had for their trials, and we also went out seining in the hopes of recapturing two sharks that had accelerometers on them.

One of the graduate students here is studying bioenergetics of juvenile lemon sharks. Basically, he has attached devices to juvenile lemon sharks in local mangrove creeks that track changes in speed of the animal. He's using this data to determine the metabolic rates of lemon sharks.

He first released tagged lemon sharks in the creeks from which he originally collected them. Lemon sharks are born in these protected mangrove creeks and live the first 4-5 years of their lives there, so he wanted to make sure that these sharks went back to where they came from. I didn't get any photos of this because he was in a hurry and the wind was insane (aka boat was rocking like crazy).

Then, we placed the seine net at the mouth of one of the mangrove creeks at high tide. Because of the blood moon, the tide was SO high. The graduate student running this project is very tall, but when he jumped in the water, the water was up to his neck. Being the shortest person on the boat, everyone turned to me when he jumped in because we knew I would not be able to touch. Sure enough, I jumped in and couldn't touch with my tippiest of toes. I had to swim to shore and wasn't able to touch until I was about six feet from shore. It was insane!

We placed the net and then waited for six hours until the tide went out. This was to ensure that the lemon sharks couldn't leave with the escaping tide, but the water doesn't get low enough that they will be stuck in there with no water. It goes down to about 1 foot of water at the shallowest and 2-3 feet of water at the deepest, just enough for the sharks to still swim (they're small). When the tide was low enough, we formed a "scare wall" and basically just walked and splashed towards the net, while a person dragged the net to form a circle, trapping in anything that was in the path. We caught 4 or 5 lemon sharks, but they were not the ones with the accelerometers, so we released them. Sadly, we didn't get the tags back, so he had to go out the next day. He was unsuccessful then, too.

I didn't get to touch any sharks, which was a bummer, but I had an amazing day. I had spent the entire week in the office, so getting out in the field was really great. Plus, I was in great company! If you want anymore information about this specific project, let me know and I can send you a link!

Are you afraid of sharks? How would you kill six hours if you had to wait?