Showing posts with label Marine Biology. Show all posts
Showing posts with label Marine Biology. Show all posts

Wednesday, November 28, 2007

The Case of the Bloated Dolphin

Last week I was presented with a unique opportunity. Friends of mine gave me a call after they discovered a dead dolphin washed up on the beach. So I dropped what I was doing and drove across the island to recover what turned out to be an approximately 5 foot spinner dolphin calf.
It looked as though it had been dead awhile, as the skin was already starting to slough off and once removed from the water started to take on a decidedly dead cetacean odor. Dead things smell. Nobody would argue that point, but dead marine mammals take that odor and somehow ferment it. As a result flies from all across the island were moving in to get their share. In what seemed like a good idea at the time I decided to put the dolphin into the back of my car. The thought was that I would keep the hundreds of flies away and it would be less disgusting later on. Well it turns out that dead dolphin is that attractive to flies that they all found a way into the car, I assume through the vents since all the windows were rolled up. So when I returned to the car 20 minutes later, there was warm smelly dolphin sealed up in a car in the tropics with hundreds of flies buzzing around inside my car. It looked like something out of a Hitchcock movie. It was at this point I considered just setting fire to the car and cutting my losses, but science prevailed and I then got to drive about 17 miles with a rotting dolphin carcass in the back of my car. Melanie and Emma contend that the car smelled for a few days afterward. Sometimes it is nice to have virtually no sense of smell.
Emma had come with me to collect the dolphin. She was really excited about the idea that I was going to do a necropsy (animal autopsy) on it and she really loves mysteries. Why this little calf had washed up on shore certainly fit into that category. So given that educational opportunities are scarce on the island, I took her out of school the next day and let her come to work with me and help with the necropsy. She was a great help and got right in there and donned some surgical gloves and started taking measurements for me. We took some initial notes and photos and then started cutting into the calf. Emma and I discussed what we saw and took notes on various biology items as we went. Emma got right in there like a surgeon and was cutting away tissue and removing organs. Pretty soon was had discovered the cause of death and were well on our way to having the skeleton cleaned as best as we could. Once cleaned, I had planned on setting the dolphin bones out and letting the bugs finish the job so I could make a skeleton display out of the bones. Incidentally, in case you wondered the cause of death was that the calf had drowned secondarily to having been struck by a boat.
So the bones of this poor little mammal will be put to some use, and other kids besides Emma and I will hopefully get to learn something from it. I am sure we’ll get some photos of the finished product when it is done for you all to see.

Tuesday, June 26, 2007

WOW -- it's big!

On day two, we headed back over to the same general spot offshore to Ta'u. Our boat captain, Andy, noticed a blip on his depth finder so Paul and Doug grabbed their masks and snorkels and jumped in to investigate. Meredith and I soon followed and we were all hovering over a very big coral. It was immediately apparent that we had in fact located the giant coral. It was 2-3 times bigger than any of the other large corals we had seen previously. We proceeded to get on our dive gear and head under.

The coral looks like a small mountain underwater. Unfortunately, light and color are absorbed the deeper you go underwater. Our point and shoot camera is better at taking close-ups underwater than wide-angle shots so you'll have to use your imagination a bit with the pictures. However, if some blogger whiz out there could tell me how to post video, we have some great quality film clips I could post on the blog. Anyways, the top of the coral is located in 25 feet of water and the bottom at 50 feet. Our work as research assistants quickly set in, as Meredith and I began measuring this and adjacent Porites corals while Paul was filming. The circumference of the coral is 41 meters. This really is big, as it took a minute to swim all the way around it. It measures over 34 x 22 meters in width and length.

Given the size of a coral, its age can be estimated. This giant coral is over 1,000 years old! That could make it one of the oldest living animals on Earth!