Saturday, May 17, 2014

Sea Turtle Research Sample Collection

Hey everyone,
I'm working on my master's thesis studying sea turtle reproductive physiology at Southeastern Louisiana University, and this summer I'm all wrapped up in collecting blood samples and ultrasound images from adult female loggerheads. I'm collecting blood samples which I will use to measure hormones and proteins to learn more about how reproduction is regulated in sea turtles. In order to do this, I've been collaborating with Inwater Research Group, a fantastic research team which (among many other things) monitors St. Lucie Nuclear Power Plant on Hutchinson Island, FL.
St. Lucie Nuclear Power Plant

St. Lucie Intake Canal with day nets set.
Ryan Welsh (IRG) PIT tagging the male nurse shark
This power plant is located right on the south eastern coast of Florida and uses a constantly running supply of sea water to cool down the reactors (circled). The plant pulls water in from the nearby ocean, and the water travels into the intake canal, water flow is depicted by arrows above, then flows around the reactors, and is then discharged back into the ocean. When this water is pulled into the canal, it regularly also pulls in marine life, including sea turtles. One example of the many different forms of sea life that can be found here includes the 7 ft nurse shark caught on my second day.

The IRG is responsible for rescuing these animals, and they do this by setting and monitoring nets (yellow) during the day to catch the turtles when they enter the canal, this prevents the turtles from traveling further into the power plant.  After capturing the turtles, The IRG weighs/measures, tags  and photographs them. The canal, in my study, acts as a random sampling of sea turtles that happen to be swimming past the intake pipes. I am fortunate enough to have the opportunity to collaborate with this team, so that I can take blood samples and ultrasound images from the adult females which become entrained in the power plant's intake canal. I am hopeful that using the power plant in this way will allow me to get a broad picture of how adult, female sea turtles regulate the production of yolk proteins over the course of their reproductive cycle.

On my very first day of sampling, we caught 3 loggerhead sea turtles, all in different size classes. The first turtle we caught was a juvenile, which aren't very commonly caught in the canal.
Juvenile loggerhead sea turtle
freshly rescued from the canal

Ryan Welsh and Serge Aucoin (IRG)
 rescuing a juvenile loggerhead
Ryan Welsh (IRG) tagging the turtle

Ryan Welsh and Serge Aucoin (IRG)
 weighing the turtle

Releasing the turtle back into the ocean
Later in the day, we caught a sub-adult turtle. I'm only taking samples from adult, female loggerheads, but it was exciting to see a live turtle after working in my lab and office all semester.

 The highlight of the day for me was ultrasounding and taking blood samples from my first adult female turtle.
Just look at that sweet face from this big mama!

Preparing for release

Sometimes I just can't believe how incredibly lucky I am

Releasing the sea turtle after her processing

We successfully got a blood sample as well as ultrasounds from this big girl. She weighed 209 pounds and her shell was nearly 3 feet long! 

When I examined the female with the ultrasound probe, I discovered that she had several ovarian follicles developing on both sides, and that they were quite large. Also, I was able to see calcified eggs inside of the female - she's ready to pop any day!

Ovarian follicles from our first female examined.

Actual developing egg from our first female examined. The outer ring (not measured) is the egg shell.

My first week in the field was extremely exciting! I could not be more thrilled to be out working with these turtles and (hopefully) to be providing some new information on the reproductive physiology of these animals to the scientific and conservation communities!

1 comment:

  1. Brie, this is so amazing! What an incredible opportunity! It looks like you're already learning tons and interacting will all kinds of precious "babies". :D Your ultrasound images are so neat - you're a pro! I'm definitely looking forward to seeing what the rest of the summer brings for you. Love you lots!