Thursday, June 12, 2014

My First Leatherback and One Nest's Story

The #1 thing on my bucket list is to see a leatherback sea turtle – and today I got to cross that off! I’ve been fortunate enough to receive extensive nesting beach survey training during the past few weeks here on Hutchinson Island – and I have many awesome stories to share from that, but I’m going to start with this one.
The purpose of nesting beach surveys is to get an idea of the number of nests each species is laying each season and how successful those nests are. My past experience with nesting beaches was in North Carolina where the nesting beaches are primarily used by loggerhead sea turtles. In Florida, there are 3 species which are commonly seen: loggerhead, green and leatherback.
When a female leaves the ocean to lay a clutch, she can frequently be scared away by lights, obstacles such as beach furniture or large holes that people dig in the sand, or animals on the beach. When a female comes out to nest but doesn't lay a clutch, it’s called a false crawl. A typical false crawl is a U-turn, but it can be much more complicated than that.

Typical U-turn false crawl - loggerhead female.

You can tell the difference between the species of turtle which laid the nests by the way they crawl as well as the size of the crawl. I’ll show other types of nests in future posts, but here’s what a leatherback track looks like – we saw this out on the beach this morning.

Leatherback crawl, Hutchinson Island, FL.

A unique characteristic of leatherback nesting is something called an “orientation circle,” the turtle does a 360° turn after she’s done laying before she returns to the ocean.

Carrie Keske next to the leatherback orientation circle.

I love leatherbacks because they have very interesting physiology, I’ve actually written a little bit about it in a previous blog here, but this summer is the only time I’ve had the opportunity to see a leatherback because they nest mostly in the tropics, and Florida is in the most northern end of their nesting range (though they travel all over the world).

Unfortunately, sea turtle nests do not always stay intact until it’s time for the hatchlings to emerge and crawl to the ocean. During nesting surveys, we keep track of nests that have been washed over by the tide, depredated, and nested on top of by other sea turtles.
One of the earliest leatherback nests on the beach I’m helping to monitor was laid on April 3, 2014 and it hatched on June 9, 2014. During the survey that morning, we noticed that there were headless hatchlings outside of the nest – a telltale sign of depredation by raccoons.
Early deprated loggerhead nest.
Leatherback hatchling predated upon by raccoons and ghost crabs.

This sight was very sad, of course, particularly since the predators didn’t even eat the entire hatchling, only the heads. What a waste of a life. It’s frustrating to see things like this when you know that every nest is important to the conservation of the species, and leatherbacks are one of the species that needs the most help.
Though I’m becoming a scientist, my love for these creatures as individuals consumes me at times. My heart hurt for this nest. It seemed that all was lost – that all the hatchlings had been eaten and this nesting effort by the mama turtle was for not.
However, as we were surveying the damage to the nest, we noticed something.

Leatherback hatchling crawl.

One little hatchling managed to escape the raccoons and make it to the water.
Sea turtles are survivors. They face so many threats each day – and unfortunately we can’t save them all. Conservation work can be a roller coaster – we lose many battles. This little turtle reminds me that for many turtles, we are winning the war. I still hurt for those babies that we lost – and all the babies we lose to predators each season – but at least one of those little guys made it to the water in the cover of night and got his chance at survival.

Three days after the turtles hatch from their eggs, we perform a “nest excavation” in which we dig out the nest and count the number of hatched eggs, the number of eggs that didn’t hatch, as well as the number of live and dead hatchlings that are inside the nest. Live hatchlings can be left behind when the others leave the nest because they need the momentum of the entire clutch moving in unison to get out of the sand.
The purpose of these excavations is to determine hatching and emerging success of the nests for scientific research as well as rescue and release any live hatchlings that might be left behind. 

Given that the nest had clearly been dug into and most of the hatchlings had been eaten, I wasn’t holding out much hope to see a live hatchling in this excavation. Between the raccoon’s quick, agile fingers and its strong sense of smell, it seemed unlikely that any more could have evaded detection. It was a somewhat somber looking morning, while we were driving up to the nest during the morning survey, it started to rain. Though it was cold and windy, we persevered and the fearless Carrie Keske began to dig up the nest – sorting hatched egg shells, unhatched eggs, etc. into their respective piles to be counted for the data sheet.
To my amazement, we found one little leatherback hatchling that had managed to remain hidden from the predators. Finally, I got to see and touch a turtle that I’ve studied and loved from afar for so many years!
I was so ecstatic to see my first leatherback today!

Check out his little yolk sac - turtles have belly buttons too (sort of)!

After his little photo shoot, we let the hatchling crawl toward the ocean to imprint, and then away he went.

Good luck little leatherback!

Sea turtle conservation is a roller coaster. It is highs and lows – victories and defeats. Maybe most of the hatchlings in this nest were eaten by raccoons – but the track of the hatchling that escaped on its own as well as the hatchling that we rescued during the excavation give me hope that all is not lost for this nest. Luckily, female sea turtles lay many clutches a season – between 8 and 12 – so it’s likely that this female had other more successful nests this year.

Today was a victory - and a victory is a victory, no matter how small.

Tuesday, June 10, 2014

She Survived - A Loggerhead's Story

Over the past few years of my education, I've been able to learn more and more about sea turtles in a variety of contexts – rehabilitation, organizing public education, nesting beaches, and now scientific research. It’s so true that the more you learn about something the more you realize how much you don’t know – but instead of being something that is frustrating, it has been a source of increasing fascination and wonder.
Science can be seen as something cold, unemotional and clinical – and that perspective is sometimes deserved. However, in my experience it’s been a method to tell a story. From the clinical side of things – my research is about physiology – hormones and proteins. But to me, it’s much more than that. 

Brie ultrasounding an adult, female loggerhead.

How an adult female sea turtle is able to produce all the calcium, fats and proteins needed to make so many eggs is somewhat mystifying. The fact that she has to break down much of her own fat stores as well as extracting calcium from her own bones to give to her offspring is beautiful in my eyes. Female sea turtles do not provide parental care for their offspring – they haul out on the beach, make a nest and lay their eggs, disguise it as best they can, and they return to the ocean, probably never to see their offspring again. Of those offspring – each individual has a minute chance of surviving their first year – much less to survive to reproduce, which can take over a decade. These hormones that regulate the metabolism of these fats, calcium and proteins and their incorporation of these constituents into the egg are the female’s contribution to the success of her offspring. The protein that I’m studying is broken down into smaller pieces into the egg yolk of the hatchling – it’s the nutrient source that will sustain the hatchling during its mad dash to the sargassum – they don’t stop swimming for over 24 hours. Every sea turtle that survives to be an adult has overcome massive obstacles, many of which we will never know about. However, one turtle I worked with last week bears scars to tell a small piece of her story: boat strike scars.

My first experience with sea turtle boat strike injuries was during my internship at the Karen Beasley Sea Turtle Hospital in 2012. The volunteers at that hospital treat turtles for a variety of injuries and ailments – including boat strikes. I've seen firsthand the damage that a boat propeller or hull can do to the body of a sea turtle – frequently cutting into the body cavity and damaging the organs and bones underneath. It’s difficult to imagine – but even when the propeller of a boat cuts into the delicate lung tissue or the vertebrae of a sea turtle or when the hull of a ship smashes a sea turtle shell into a dozen pieces – they can often be nursed back to health with delicate, professional care because of the amazing fighting spirit that sea turtles have.

So, given that I've seen the horrific consequences of a boat’s interactions with sea turtles, and the great amount of care required to nurse them back to health – imagine my surprise when we catch this lady for my research.
An adult loggerhead female with significant scarring from a boat strike.

She has very large scars on the side of her carapace that are a telltale sign of a boat strike. She also had no tags or scars on her flippers to indicate that she had ever been cared for in a rehabilitation facility. I was deeply moved to see that this turtle had clearly sustained massive injuries as a result of this boat strike – but managed to heal on her own in the wild.
How can you not fall in love with that face?!
I felt my chest swell with pride when I saw the extent of these old injuries, she’d faced the worst and lived. As I ran my hand over her scars, I thought back to the extensive treatment protocols we used to treat such injuries - antibiotics, pain killers, daily disinfection of the wound, regular debridement to ensure the shell healed properly, daily tank cleanings and water changes, the list goes on. This turtle experienced huge amounts of blood loss, excruciating pain, and lived with an open wound that would remain open for weeks if not months. Despite the pain and weakness she must have felt, she still managed to feed herself, avoid predators who would surely target a turtle with such an injury, and miraculously avoid deadly infection and parasites. If there's a definition of a survivor - she's it.
A close up of the boat strike scars.

It was particularly emotional for me to ultrasound her and find shelled eggs in her reproductive tract. She’s not only recovered well from her injuries, she’s healthy enough to be out there laying hundreds of eggs, containing the genes of a warrior.

This ultrasound image shows a shelled eggs surrounded by developing ovarian follicles.

This survivor could be out on the beaches any day laying a clutch of eggs. Thank you, Mama, we need many more little loggerheads out there like you.

Though many species of sea turtles are endangered, though they face a long list of threats every day, I refuse to give up on them. I have witnessed a few of the horrific circumstances that kill off many – but still, some survive. I've dedicated my life to helping them through scientific research and conservation, because if they won’t go down without a fight – why should I?
Brie with the turtle. I'm so excited to include her in my study!
Releasing the turtle. After we weighed, measured, tagged, ultrasounded and took blood on her - she was back where she belongs!