Turtle Barnacles from a Turtler's Perspective

These Chelonibia 'testudinaria' type species are from Baja and they are different from elsewhere.

For the past few years, I have grown increasingly more interested in turtle barnacles. There is very little information available on their natural history and no one has scrutinized the morphology of many species. In the world of barnacle research, taxonomists like to recoginize species by differences in shell morphology. This is done so that extant species can be compare to fossilized specimens; because the soft parts inside of the shell do not fossilize well. As a result, more contemporary analyses of the soft parts of barnacles (i.e. the cirri and muscle attachment to the shell) are revealing subtle differences between distinct regional populations.

Even genetic data agree with the analysis of soft part morphology in some cases. However, some intertidal species have shown drastic differences in regional population genetics, yet there has been no discernable changes in morphology. In other words, they all look the same but are vastly different on a genetic level when compared between ocean basins. Some herpetologists have experienced a similar trend in salamander analyses. There are several species of slimy salamanders (Plethodon glutinosis sp.) in the eastern US but they are very difficult, if not impossible, to tell the difference between species externally.

We are seeing interesting things with the barnacle Chelonibia testudinaria thanks to the many friends that have participated in a phylogeographic analysis of this turtle barnacle species. Recently, barnacle taxonomists, turtlers, and geneticists have aligned to start from scratch.

I say start from scratch because that is what one has to do when straightening out the taxonomy of turtle barnacles (genus Chelonibia). The authenticity of Linneaus' specimens are questionable and it is difficult to 'borrow' anything from the Darwin collections nowadays. Besides the specimens that were assigned to the Genus Chelonibia, the type specimens, have no data as to locality or host. That is, Ch. testudinaria according to Linne. could be what we call a Ch. patula from a horseshoe crab. We just don't know.

Paul Rawson at the University of Maine in Orono and a student of his, Rachel Macnamee, decided to take on a project I suggested examining te phylogeography of turtle barnacles. Knowing I could count on my friends abroad: Dimitris Margaritoulis, ALan Rees and the rest of the gang from Archelon in Greece, Yoshimasa Matsuzawa and Umigame in Japan, Dave Addison and the gang from the Conservancy of Southwest Florida and J. Nichols and his gang in Baja California Sur, Mexico; The Caretta Research Project dragged these poor souls into the sordid world of barnacle genetics.

The cool thing was that there were already tagging studies and genetic studies on loggerheads from these region to compare our data to - we did get all of our samples from nesting loggerheads, except for J's turtles which are immature individiuals from the Japanese nesting population.

The mtDNA analyses indicate that the barnacles currently recognized as Ch. testudinaria are actually at least three different species despite similar shell morphology (see picture above). The turtle barnacles from Florida, Georgia and Greece represent a single species, whereas the Baja barnacles and the Japanese barnacles were totally different on the species level. My friend and mentor, Arnold Ross agrees that the shell morphology (subtle differences) and perhaps soft part morphology jive with our results. Apparently, the life span of the testudinaria in the Pacific is not long enough for young turtles in Baja to transport the barnacles to Japanese host turtles. Ed Standora is doing some stats work on the shell morphometrics to help with this project as well.

We have more studies and their results are in prep right now. The aforementioned testudinaria data is under review right now. Within the next couple of years the information available on the natural history of turtle barnacles is sure to double.

The Exorcist Turtle

On Wassaw Island, Georgia, USA, my collegues and I have the luxury of literally 'knowing' some of the loggerhead turtles we work with. That is, there are some turtles we have met long ago and have known for quite a few years. For instance, there is a turtle we call 'the Exorcist turtle'.

In ~ 1990 this turtle was found by me and my cousin, Ed Strohsahl, on the south end of the island. She was nesting and we had just begun to tag her when she suddenly seemed to stop breathing. She rolled her eyes upwards, opened her mouth and then let out a bellowing gurgle. As her mouth was open, you could see bright green algae growing all over her lower jaw and into her mouth. Because she appeared posessed and the algae resembled pea soup we dubbed her the Exorcist turtle.

Since then she has lived up to her name. The Exorcist has never had a nesting emergence where something odd hasn't happened. Once, she crawled from the ocean and proceeded to dig what looked like a nest in the surf. When we got to her she was laying eggs and they were being carried about by the surf. She even went the through the motions of covering while in the water! We collected the eggs and the man-made nest had a good hatch rate. Although, at this time we were wondering if we should help this turtle usher her genes into the gene pool. Nonetheless, the Exorcist continued to come back, occasionally laying nests in really good spots. However, these events were not graceful.

Another time she nested, in a good location, she crawled into the woods rather than to the ocean. We spent over two hours looking for her and another thirty minutes getting her back to the dunes and off to the ocean. The exorcist has also false crawled after running into a Spanish/American War fort on the north end of the island - a very large concrete structure. She has even gotten tangled up in a dead Christmas tree that was washed up on the beach.

The exorcist also has no visible carpace. She is covered by so many bryozoans and sea squirts that she looks like a chunk of sod with flippers. One night when I sampled her for epibiota I decided to remove everything from her shell - I guess I felt she needed a handicap. Anyways, one-third of what we have reported living on loggerheads in Georgia first came from this sample, including a wily polychaete worm that bit the fire out of me. In 1999 she laid five nests on Wassaw and there was a gap of four weeks in between nests 4 and 5. So, it was obvious she had nested elsewhere and deposited at least 6 nests that season.

The last time I saw her, in 1999, I had to swim into an alligator infested lagoon to retrieve the lost turtle that had been there for several hours after sunrise. Although she can be a pain in the rear sometimes, I miss her. Maybe we'll see her next season.

My First Blogging

Luckily I've had the opportunity to see the bloggings of others before having to construct my first blog. One interesting thing that I noticed in the letter that I had received, asking me to participate in this blogging endeavor, was the term "turtler". We've all heard it before and unconciously accept it as a real term to identify an individual as "one who turtles" ('turtle' now acting as an adjective and later a verb). That is, a person who works with sea turtles is a turtler and the act of working with turtles (i.e. beach surveys, in-water captures, aerial surveys, etc.) is called turtling. Here are some examples in sentences of these words and their usage:

"Mike couldn't make it tonight because he went out turtling. Nothing could pull Mike away from the beach tonight anyways, he loves to turtle. He feels his best when he turtles. Yep, that boy is sure one turtling fool. Some folks call boys like that 'turtlers'."

Anyways, I just thought for a second there that the word 'turtle' is really not just a noun. Now it is an adjective, verb and a noun. Someone should notify Websters.

Yesterday, some comrades of mine, especially one gent named Michael Newcomer, went down in the Atlantic off of Fernandina Beach, Florida while doing aerial surveys for N. Atlantic Right Whales. Due to the current temperatures it is likely that all four are dead. I worked for two years doing the same surveys and such a demise always haunted me when I went up.

Our surveys were along the Georgia and Florida coast out to twenty miles. We flew a ladder transect from Little St. Simons Island south to Jax Beach every day from Dec 1 to Mar 31. Often it was very cold and on some days extremely hot. The plane rides were cramped and relatively bumpy, occasionally very bumpy.

Upon sighting a whale or in some cases courting loggerheads, basking sharks, mola molas, etc., the plane breaks the track line and circles the whale from about 700 feet, give or take a 100 ft or so. The right wing of the plane is turned down and the entire plane turns clockwise in a tight spin. During this time the plane flies into its own backwash and the pilot struggles to keep the plane right over the whale(s) so that someone on the right side of the plane can hang out of the window and photograph the whales - the callous patterns on the head serve as a living tag of sorts. Meanwhile, another person is viewing the whales through field glasses and drawing the callous patterns and listing all of the locality information concerning the sighting. Also, another person is on the radio reporting the sighting to the U.S. Navy to alert local vessels of the whereabouts of the sighted whale. As you can see, a day can be very 'busy' if you seen many whales in one day and it takes an iron stomach to work on an aerial survey.

Amazingly, the hawk-eyes at the the New England Aquarium in Boston, Mass., particularly Amy Knowlton as well as others, are capable of matching the slides taken during the aforementioned photo shoots to those taken at breeding grounds in the Bay of Fundy, Maine. At times, there are up to three generations of right whales present off of the Florida and Georgia coasts during the winter. And, from these photos they also know that there are approximately 300 individual whales left. However, some whales seen at the breeding grounds are never seen at the calving grounds and vice versa. This means that there may be either 'secret' calving grounds or secret breeding grounds elsewhere, perhaps both.

Aside from the science, the aerial surveys are also an awesome opportunity to see animals that you've only read about or seen on television. I've seen basking sharks breach like whales, turtles sitting in an ocean of rays and eating the migrating fish as they swim by, I've seen a leatherback and a loggerhead literally bumping elbows while eating jellyfish.

One day, when we were in our plane flying just over the surface of the water in front of Cumberland Island, a leatherback popped out of the water and grabbed a gulp of air, less than 20 feet away from my window. That second is etched into my mind and I can still see the perfect face of the turtle, its size and its dark color. I can see the tan water explode into white when the turtle breaks the surface of the water; and I can see the majectic beauty of a Georgia Barrier Island and its green canopy off in the distance. Most importantly, I can see the billow of smoke come from the turtle's nose as it exhales in the frigid cold of that gray February afternoon.

I am sad to hear that some of my field-mates are presumbed dead after their plane crash, and I'll always worry in the back of my head when I fly; but the experience of soaring over the oceanic realm and peering into it will always supercede notions of fear. Best to all who knew the departed.