Woods Hole Oceanographic Institute

On Monday, August 1^st I went to WHOI, the Woods Hole Oceanographic Institute, with my mom, Amanda, and Matt.  When we arrived, Kelly took us to the Redfield Laboratory where we met three interesting scientists. 

Part 1: Leatherback Turtles

            First, we met with Kara.  She studies leatherback turtles to learn more about them and how they survive.  Leatherback sea turtles cannot be put in captivity because their brains are the size of a thumbnail and they will continuously swim into the tank wall until they are in bad condition. Their tiny brains are telling them to migrate. That means scientists need to study them in the wild. 

            Kara told us how they put trackers and cameras on leatherback turtles. She showed me all the interesting technology they have, including their VHI frequency radio trackers and acoustic trackers.  Eventually the trackers fall off of the turtles.  The trackers each have a suction cup, which they use to attach the tracker to the turtles.  The scientists seal the opening in the suction cup with zinc foil.  A copper fastener holds the foil in place.  When the zinc foil and copper come into contact with the salt water, which is an electrolyte, corrosion begins.  The thickness of the zinc foil or in their case the number of foil sheets they use determines how long the suction cup stays attached.  Once the zinc foil corrodes, the suction cup comes off the turtle. To learn more about this process research bimetallic (two metals) corrosion.  

            It is a very hard job tracking the turtles. To tag the turtle they first have to find the turtle, which is hard.  Leatherback turtles are endangered and can dive up to 4,000 feet.  After they find the leatherback turtles, they need to get these huge turtles onto the boat! They can way up to 2,000 pounds. They have a 9 foot wing span and are over 6 feet long.  They use a hoop-net and a ramp that they pull the turtle onto.  Then they inflate a ball under the ramp to level it, so they can get the turtle into the boat. 

            Once Kara and her team recover the data from the trackers, they found that almost all the turtles swam thousands of miles towards the equator and then stopped and turned around before crossing it.  See the picture below to see the different routes the leatherback turtles they tracked took.  When they travel, they stay on a steady but slow pace (about 40 miles a day) and don’t stop once. Some took “vacation” in the Bahamas while some preferred Brazil. After breeding, they swim back to the east coast. Leatherback turtles only eat jellyfish and Martha’s Vineyard has cool water perfect for jellyfish, so it is a perfect place for leatherbacks.  

            I can’t wait to read more about what they learn.  To read about Kara’s work click here. You will find some cool videos also.  

Other Interesting Facts I Learned: 

         Unlike most turtles, leatherbacks have a thin black skin covering their whole body including their shell!

         Scientist can tell how old leatherback turtles are by looking at their growth ring in the eye bones.  Kara said that they believe they have a short life span, around 50-60 years.

         Leatherback turtles eat ½ their weight in jellyfish eat day.

Part 2: Fish Larvae

            After we finished learning about leatherback turtles, we met a scientist named Joel.  Joel studies how fish and fish larvae feed in different conditions in different environments.  They catch fish larvae with a very fine layered net and scoop them out of the ocean.  Then they find and sort the fish larvae so they can study.   Joel had many different types of fish larvae in vials. 

            All fish have ear stones called otolith, which are basically little rocks in the heads’ of fish. These ear stones can tell us when the fish were born.  When the fish are young their ear stone grows one ring each day. Once they get older, their ear stone rings become less visible and soon instead of seeing a ring every day, you can see a thicker ring every year. The ear stones are microscopic and have to be taken out of the fish with a dissection microscope. 

            Joel also showed us an interesting slide show.  In the side show, we got to see a picture of a sailfish in its larvae stage that had already eaten a tuna and a lantern fish.

            He talked about the eels that I have seen before at Lambert’s Cove.  I went to a river nicknamed the Coca-Cola River because of the color.  It is fresh water river that connects to the ocean.  The river looks still.  I found tiny eels that are super hard to catch, but I didn’t know anything about them.  Joel told me that the eels are catadromous, which means that they are born in salt water and they go into fresh water, unlike salmon.  Salmon are anadromous which means they migrate up the river from the sea to spawn.  Both animals are diadromous meaning that they spend some of time in salt water and some in fresh.   

            To learn more about Joel’s research, click here

Part 3: Environmental Toxicology

            The next scientist we met was Matt.  He studies environment toxicology and developmental biology. He works with zebrafish and explained how he implants different genes, using a microscope and a micro-injection system, into zebrafish embryo’s to make them albino, have longer fins, or other traits.  It was really to look the zebrafish embryos because the embryos are transparent and you could see the fish moving around inside embryo.

            Matt can study things like environmental toxins.  Matt was studying how environmental toxins influence gene expressions.  To learn about epigenetics, check out this video here

            It was very interesting and I will look more into genetics.  This is a video genotypes and how gene expression works click here

            To read more about Matt’s work click here