Leatherback Sea Turtle Tagging: Notes From the Field

From: George Lewis Shillinger

Sent: Thursday, February 03, 2005 12:15 AM

Subject: Playa Grande Update

Dear All,

I am writing to update you on our progress. The past three nights have been tough. The tides have not been on our side and the turtles that emerged and nested successfully have been limited to viewing by eco-tourists. Based upon this season's data, we are expecting several turtles tomorrow. We had three turtles abort nests tonight (conflicts with dry sand and vegetation) so a few of these turtles will probably also return tomorrow night.

Scott Eckert confirmed that the 12 remaining tags arrived in Beaufort yesterday and he is making arrangements to prep and to ship a portion of these tags to Costa Rica. This is a lot of work and I am grateful for his help.

The tourism season will be closing on Feb. 15 and all turtles will be available to tagging from then on out -- but numbers will probably be low (2-5/night on good nights and 0-2/night on bad nights) for the remainder of the season. The good news is that the team will be in place through the end of the month.

I am optimistic that we will get several more tags out and am hoping that we will luck into a big night soon. A 9-10 turtle night is projected late next week....so we'll see ...

That's all for now -- I will keep you posted as soon as we deploy more tags.

Thanks and all best,

George


Sent: Fri 2/4/2005 10:33 AM

Subject: 4th tag Deployed at Playa Grande

Dear All,

I am writing to let you know that we successfully deployed another transmitter last night: TOPP ID: 2605004, TAG CODE: SA049569, PTT#:56276.

The tagged turtle was one of the females that aborted several nesting attempts [in?] two night[s?]. She returned to virtually the same spot on the same beach at approximately the same time as the previous evening. Once again, her initial nesting attempt was high on the berm and in somewhat dry sand -- resulting in another nest collapse. On her second attempt, we assisted her by patting down the sides of the chamber and clearing away dry, loose sand. She finally succeeded and we deployed the 4th tag of the season.

Last night four turtles in total arrived at the beach. The first three turtles went to each of the three tourists groups: Matapalo (two groups of 30 individuals, each) and the other turtle was viewed by the Tamarindo group (one group of 30 individuals). Per protocool and via an agreement with the local communities of Tamarindo and Matapalo, these turtles were off-limits to the scientists for tagging -- and were used for tourism (observational) purposes only. Two of these three turtles initially aborted their nests, but subsequently laid eggs.

Nine days ago there were no turtles encountered on the beach and ten days ago, three turtles were encountered. Based upon this information, we anticipate anywhere between 0-4 turtles tonight --- so we will be very lucky if we have the opportunity to tag one!

That's about all for now. I will try to send a picture or two later.

All best,

George 


Sent: Mon 2/7/2005 7:45 AM

Subject: Playa Grande Update

Hi All,

I am writing to provide you with a quick update on our progress. So far, we have tagged 4 turtles. This had been a challenging season due to low turtle numbers, high tourism (turtles must be shared and "tourist turtles" are off-limits to scientists for tagging), and dry conditions that confound nesting efforts (more nest collapses). In order for us to apply the tags, the turtles must first initiate egg-laying. Egg-laying requires the creation of a successful nest. After subsequent nest collapses, females frequently depart the beach, generally returning to try again the following night.

One turtle emerged 3 nights ago and we had exclusive access to tagging this turtle but she aborted her nest after two attempts -- due to repeated nest collapses on the dry sand. This turtle returned the following night and was one of 3 turtles on Saturday that were allocated to the tourists.

Unfortunately, no turtles emerged last night, event though the tides were in our favor (late) --- for tagging w/reduced possibility of tourism competition. The Costa Rican tourist season is winding down, so it is probably that we will have more chances this week.

I have rescheduled my flight to return next week in the hopes that we will get at least 4-8 more tags deployed during the next 7 days. I am going to talk to the Park management this afternoon to explain the importance of our work and explore whether or not a compromise may be possible that will enable us to tag the turtles after the tourists have had a good look at them. The team here seems to think that the Park Director and his team might be open to this possibility given the challenges that we are facing at this point in the season, and the importance of our efforts for turtle research and conservation.

I have been watching our turtles on the LAS and it appears that a few may return to the beach in a few days. This will give us a opportunity to check on the attachments. It also appears that one of the turtles has left the beach for the high seas.

That's about all for now. I'll keep you posted on our progress as news develops.

All best,

George

 


Sent: Tue 2/8/2005 1:07 PM

Subject: 5th and 6th tags Deployed at Playa Grande

Hi All,

Great news from Playa Grande in this report! We had a banner tagging evening last night -- and tagged the following two turtles:

TOPP ID#: TAG CODE#: PTT #:

2605005 SA049569 56280

2605006 SA049564 56268

We had a total of 4 turtles arrive at the beach between 00:20 and 04:30 hrs. Fortunately, the first turtle was one of our tagged turtles (TOPP ID: 2605003, PTT# 56282). This turtle was allocated to all of the tourists from both Matapalo and Tamarindo. The tour groups took turns observing the turtle, after which they departed the beach entirely --- leaving the scientists with access to all potential remaining turtles. We had an excellent opportunity to observe and assess the tag attachment on this turtle. It was holding up extremely well, with no signs of abrasion on the turtle or wear on the harness.

The second turtle was spotted emerging from the surf at 01:50 hrs. She was one of the largest turtles that we have tagged to date. Most noteworthy about this turtle was the smoothness of her carapace and her overall girth and thickness. She was also one of the more senior turtles in the record books on the beach -- first PIT tagged during the 1994-95 season.

She returned to nest in 1996-97 and in 2000-2001 and this year. So far this season she is on her second recorded nest. The tagging operation went very smoothly --- after which the turtle wasted no time returning to the sea.

The third turtle arrived at 03:39 hrs. She was slightly smaller (but still much larger than average) and was also initially tagged 10 years ago during 1994-95. She returned during 1999-2000. This tagging operation also went extremely well, with the turtle beating a hasty retreat to the sea.

All in all, we were very fortunate -- due to the late tides (01:45) and tired tourists -- to have an opportunity to deploy two tags. We are optimistic for similar luck tonight with high tides projected to occur approximately 45 min to one hour later than last night. We also anticipate that we may see a few more of the previously tagged turtles -- as they return to the beach to nest again.

That's all for now.

All best,

George 


Sent: Wed 2/9/2005 11:50 AM

Subject: 7th Turtle Tagged at Playa Grande

Hi All,

I am writing to inform you that last night we deployed the 7th tag on a leatherback sea turtle at Playa Grande. The tag information is thefollowing:

TOPP ID#: TAG CODE#: PTT #:

2605007 SA049570 56283

We tagged the only turtle that arrived at the beach. This is her first season at Playa Grande. She initially arrived and successfully nested on January 7, 2005. This turtle was missing her right rear flipper at the joint. The likely cause of the missing flipper was a shark bite, as significant scarring in a "bite orientation" surrounded the stump.

Aside from the missing flipper, the turtle appeared healthy and has nested sevearl times already this season. We were lucky to tag her, as two group of tourists waited several hours for her to nest, but departed after she aborted her first two attempts. We tagged her after she started laying eggs at 03:24 hrs. on Feb. 9. She returned to the sea at 04:35 hrs.

We are expecting to received 4 more satellite tags this afternoon. At the moment, the tags are being held in Customs in San Jose, Costa Rica. We will have another night of late high tides and anticipate that we may have chance to deplopy another tag tonight --- assuming tourist attrition and new turtles on the beach (other than the internesting turtles that we have tagged already)

 

All best,

George

 


Sent: Fri 2/11/2005 6:41 PM

Subject: 8th Turtle Tagged at Playa Grande

Hi all,

After an intensive night of searches and beach patrols by the Playa Grande team of tour guides, scientists, Earthwatch volunteers, and project staff, a leatherback sea turtle was encountered emerging from the surf at 03:50 hrs. A group of approximately 30 tourists led by the Matapalo guides gathered to watch the turtle, which subsequently experienced two nest collapses. Following the turtle's two nesting failures the tourists headed home to get some sleep. Their departure afforded us with an opportunity to tag the turtle -- pending a successful nesting attempt.

We were radioed to tag the turtle after the tourists departed at approximately 5:00 A.M. The turtle finally realized success as the sun rose over the beach, providing us with our first opportunity to conduct work without headlamps and to photograph the tagging process and the turtle's eventual departure into the surf at 06:45 hrs!

The tag information for the 8th turtle is the following:

TOPP ID#: TAG CODE#: PTT #:

2605008 SA049555 56279

Today's turtle is a newcomer to Playa Grande this season. She measured 149.5 cm CCL (curved carapace length) and 106.0 cm CCW (curved carapace width). She successfully completed her 8th nest of the season. As such, she challenges the prevailing notion that new and "younger" turtles (first recorded season) tend to be smaller and less fecund (fewer nests) than the "older" turtles on the beach. The Playa Grande norm for CCL is approximately 145.0 cm, and the norm for CCW is approximately 104.0 cm. The mean number of nest per turtle is seven.

Several scientists couldn't resist the opportunity to follow the tagged turtle in the surf, as she headed out to sea having completed what might have been her final nest for the season.

As we close in on our field season goal of ten tagged turtles, I should note that our tagging efforts at Playa Grande would not be possible without the amazing support of numerous collaborators, including: Costa Rica's Ministerio del Ambiente y Energia, field biologists from Drexel and Indiana Purdue - Fort Wayne Universities, the guides and park guards at Las Baulas National Park, the Leatherback Trust, the Earthwatch Institute for Field Studies, Wider Caribbean Sea Turtle Network (WIDECAST), the Block Lab of Stanford University, the Tagging of Pacific Pelagics (TOPP)Program, Conservation International (CI), UNESCO, and the United Nations Foundation. All of these organizations and the individuals that represent them have contributed considerably to our efforts and deserve recognition for their support.

I will keep you posted on our progress tonight -- the team is already set and engaged in all-night patrol!

All best,

George