Dead Sea Turtle, Ho!

Photos here

While on survey today, I spotted something large and white bobbing up and down in the water. So did Cristela, the other dolphin observer for that shift.  We both assumed it was a large buoy for some kind of fishing net; a lot of buoys around here are just blocks of styrofoam.  But our fishing gear observer for the shift, Ely, didn’t say anything.

Someone said, “Hey! Buoy there!”

“No…that’s not a buoy…” responded Ely, “Maybe…it’s Potol?”

‘Potol’ is a nickname for one of the Irrawaddy dolphins who lost both tail flukes somehow; potol means ‘cut’.  Just this Tuesday, fishers told my field assistants that they’d seen him floating, dead, in between two fishing villages. It would be really good to find the body, to get whatever information possible about the animal and the potential cause of death.  However, he hadn’t been found again.

It soon became clear that this was definitely not a dolphin.  But it did look white and misshapen, like something decomposed.

“Ah, pawikan!” exclaimed Cristela. “Yay!”  ‘Pawikan’ is the Tagalog word for sea turtle.  I was excited, too – they do come into the inner part of Malampaya Sound, but not often.  But, of course, it was a very, very dead sea turtle, with a bleached shell and very bloated neck.

Floating by our boat

We stopped our survey and went to collect the body.  Archie, Ely, and Ricky headed these efforts, with Romeo the boatman steering.  It took a few tries, but their improvised dead sea turtle collector (a big basket and rope that were on board) finally succeeded.  There were a couple of crabs hanging out on the turtle’s shell, but they quickly scuttled into the water.

It was a hawksbill turtle (Eretmochelys imbricata).  Distinguishing characteristics include the pattern of the scales (scutes) on the shell (carapace) and the scales on the head, and the mouth, which, not too surprisingly, looks like a beak or – one could say – a hawk’s bill.

It was pretty foul-smelling, and had probably been dead for a few days.  Someone videotaping the process got footage of me saying, in an embarrassingly little-girl voice, “YOU’RE SMELLY!”  I suppose that’s better than the day when we had a fantastic dolphin sighting, but I was growing frustrated with my camera (something’s been wrong with the lens-camera connection, and it wasn’t focusing) – just as one of my field assistants was getting footage of the dolphins to show to innocent schoolchildren, I unleashed an uncharacteristic stream of profanity.  Going to have to edit that footage…

Anyway, I’ve actually never seen a relatively freshly dead sea turtle before, and thus have never even sat in on a sea turtle necropsy.  One downside to relatively recently adding the word “marine” into my job description of “ecologist” (or, more accurately, “ecology student”) is that I am lacking some general background field training.

But…it’s not all too difficult to figure out general measurements to take.  Measured the shell at its widest and longest points and the flippers.  Checked to see if there were any tags that other researchers may have put on the flippers (there were none).  Took some tissue samples (from the scutes and the neck) and plopped them in a bottle with some alcohol to preserve them in case researchers with WWF or local universities wanted to study them.  Took a ton of photos.

Then it was time to bury it.  Not because we believed that it needed a decent burial in order to go to sea turtle heaven, but because we wanted to leave the body where it could easily be found again.  This way, WWF or whoever is interested can return later, once decomposition has progressed further, and collect the skeletal remains.

We brought the turtle to a small island nearby, and Zi and Ricky found a spot where we could lodge it against rocks above the high tide mark. I looked for any obvious marks or wounds.  The neck was very bloated, but I couldn’t see anything that stood out to me as a major wound – the skin didn’t seem to be broken in any way that would correspond with fishing gear entanglement.  No marks by the mouth, either.  Right before we buried it under rocks, I realized that I’d forgotten to check on the sex (whoops), and took a quick peek at the back part of the shell (carapace) – the tail was long and thick, extending way beyond the carapace.  Our poor dead turtle was a male.

After recording the location on a GPS unit, we resumed our dolphin survey.  We only had one dolphin sighting, and it wasn’t a particularly good one (the wind had picked up, forming small waves and making it hard to see the two individuals in the group).  So…the dead sea turtle added a bit of excitement to a “meh” dolphin survey day.

More info on Hawksbills
Photos here
Video to be uploaded sometime…

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