Howlers and Triangulations

On Friday afternoon, we volunteers headed out to the estuary to embark on a tour of the local wildlife. Our guide, Enrique, graciously welcomed us at the shoreline, and he helped us onto the small motorboat. The breeze greeted us, and we snaked our way through the mangroves. As we cruised along, Enrique pointed out various impressive birds, hiding in the trees. "Tri-color heron esta aqui," he quipped. I strained to see what he was talking about; only branches appeared before me. But, just like a hidden picture pops out, I spotted it. Iguanas graced the shoreline, and brilliant birds dotted the branches. Suddenly, Enrique slowed the boat. "Crocodile, aqui." We all strained to look. Luckily, I saw the classic bony backside before it wriggled out of sight. I noted how unbelievably rickety the boat was and silently prayed that no capsizing would occur today.

Finally, Enrique shored the boat, and told us to exit. He led us down a trail, more heavily into the forested area. After about 5 minutes of walking, we came to a huge tree. Enrique bellowed out a loud, guttural noise and shook a large plastic bottle filled with rocks. What was he doing? What was going on? Suddenly, an echo of the same guttural howls filled the sky. I looked up to see a whole troop of howler monkeys resting in the treetop! I saw a baby crawl towards her mama - how adorable! I also noticed a liquid falling from the tree in the distance. Realizing what that liquid was, I quickly made sure I was not standing directly under any member of the howling troop.

Back at the field station, beach work needed to be done. Nick, a witty biologist who hails from New Jersey, and Grant, a free-spirited Minnesotan biologist, set out to take temperatures of the existing nests. Rachel, the animal-loving biologist from Texas (who also happens to be the best surfer of the group!), left to perform excavations of several nests. I went with Jacob, the same "Turtle Whisperer" biologist with whom I worked on the leatherbacks, and another biologist named Jacob, whose North Carolinian accent could melt butter. Our job was to perform "triangulations."

Triangulations refer to the measurements the scientists take of the nests the day after one is made. Remember how the scientists place a temperature chamber ("TC") in the nest while the turtle lays her eggs? They use this TC not only to take temperature readings, but also for triangulation measurements. They measure and record the distance from the TC in the nest to the nearest north, south, and tide markers on the beach. This way, should a TC be lost or destroyed, the scientists still have a record of where nests are and monitor them for hatchlings.

Beach work, no doubt, can be tedious. However, these jobs are necessary in order to follow the life cycles of the turtles accurately. Working outside on the beach can also make a person hot and sweaty very quickly. However, a dip in the Pacific is a easy cure for any discomfort!

More Earthwatch Moments

Several of the Earthwatch volunteers, Esha, Maria, and Mike, posed with a model of a leatherback turtle before dinner. The volunteers are all fabulous people, and I've enjoyed getting to know each of them and their stories. Esha is an Engineering major at the University of Maryland, Maria is finishing her MBA at the University of Colorado at Boulder, and Mike traveled all the way from England to participate in the expedition. The other volunteers include Claudia from Germany, Lydia from England, and Don from Los Angeles. All are intelligent, adventurous people, who have an interest in the environment and wanted to do something meaningful with their holiday.

Patrolling the beach at night can be taxing on one's body. Have any of you ever worn hiking boots and hiked on the beach for 8-10 miles? Sand finds its way into your boots and rubs your feet like sandpaper. After the first night, Maria and I were both in pain. The biologists recommended duct taping bandages to the blisters. We were desperate, so we taped.

Both of us confirm that this works! And our feet are much better now. Another use for duct tape!

Last night, I had hatchery duty. Several olive ridley eggs hatched in the hatchery the night before, and the biologists were hopeful for more. This nest had been relocated from another beach, where both tourists and lights prevailed. A local Costa Rican called the field station about the nest, and the biologists were happy to relocate it to the safer location of the hatchery.

My shift started at 6:00 p.m. No hatchling action occurred, so Rachel, the biologist with me, gave me an astronomy lesson. Jupiter sparkled, along with Pleiades (the 7 sister cluster). Orion's belt hovered above us. Never have I seen so many constellations at one time, as the lights from our cities back home cause us to miss this brilliant show each night. And, since the shift was 5 1/2 hours, it was fun to watch the rotation of the stars throughout the sky.

At approximately, 10:30 p.m. two beady eyes glistened in the dark. Racoons! They were looking for an easy meal. Supposedly they can smell the hatchlings before they emerge. In the dark, the eyes just stared. We called out, hoping to shoo them away, but no luck. Rachel, a lover of all animals, picked up a large stick and approached them, trying to scare them. No movement. The eyes just held still. Rachel moved closer. Still no movement. It was like the racoons were double-dog daring her to come and get them. Finally, Rachel darted towards them, and the racoons scampered away. These hatchlings are lucky to have an "armed" guard!

My shift ended at 11:30 p.m., and the next group took over. I was pleased to go and get some sleep,  and I did not envy the beach patrol groups that left at 10:30 p.m. to return at 4:30 a.m. Nonethess, I had another hatchery shift at 6:00 a.m. so off I went to sleep.

At dawn, not fully awake, I set out again for the hatchery. I looked at the nest and doubted that any more eggs would hatch. But, suddenly, I saw sand grains move. Was it an insect doing that? Or, could it really be a hatchling finding its way to the surface? I waited. And I waited. And I waited. The biologists have a lot of waiting to do. Finally, I saw a nose poke out of the sand. A hatchling!

After about 10 minutes, the hatchling's eyes emerged. This little guy must have been exhausted from tunneling its way up to the surface.  Finally, a flipper. Then another flipper. I marveled at the 2 inch olive ridley that arrived. I noted all the clacking of the birds. Were they hungry? Or were they just normally this loud? Fearing that a bird would swoop down and snatch my little hatchling right in front of me, I placed it in the bucket to take back to the field station. There, the biologist will take its measurements and release it later tonight.

Hello, Gorgeous!

Turtle Tracking

I had last night off from turtle patrol, and instead was assigned to "morning walk." The main purpose of this patrol is not only to see if any turtles arrived late morning to nest, but to monitor any turtle tracks of hatchlings fleeing for the ocean. Of course, if a hatchling is found, it is carefully taken back to the field station for release later that night. Not only do birds like to eat these little guys, but sand crabs and racoons, among others, find them to be a delicious meal.

Still dark, my team led by biologist Rachel, headed out at 4:30 a.m. to walk the entirety of Playa Grande. The most beautiful crescent moon hid behind the tree line, along with what I believe was Venus. My eyes finally adjusted to the dark, and I searched for turtle tracks. Even though it is my fifth day on patrol, I still have trouble identifying turtle marks in the sand in the dark. Rachel suddenly veered up to the dry sand and announced, "Yep. These are ridley tracks." I'm amazed at her eye; to me, it just looked like disheveled sand. We recorded the location, and searched for any stray hatchlings. None were found, so we kept moving. 

The sun rose, welcoming us to another beautiful day. There is nothing quite like sunrise. The tranquility of the daybreak invigorated me, despite the short night's sleep.

As we neared the end of the beach, Rachel pointed out the tracks of a black turtle who had come to nest that night. It looked like a BMX bike had been on the sand, but upon closer look, I could see the flipper impressions in the sand. Rachel told me that the black turtles go up the beach one way and down another; this contrasts from a leatherback, who tends to go up and back on the same pathway.

(I didn't take the above picture of a leatherback and her tracks. A biologist gave it to me to show how the leatherbacks literally plow their way through the sand.)

At 7:15 a.m. we finished our six-mile patrol. I plopped back into my bunk, in hopes of getting another few hours of rest before breakfast at 11:00 a.m. Since the work is nearly around-the-clock and no one person ever has the same schedule, the biologists advised us volunteers to nap when we could. I'm in awe at how hard these scientists work; they are extremely committed individuals, who live by strong principles.

After our morning meal at Keke's (a quaint, local establishment that feeds the Earthwatch team twice a day: once at 11:00 a.m. and again a 6:00 p.m.), we volunteers all got to go to a local black sand beach to snorkel. This group of volunteers is amazing; we have very different backgrounds, but each is enthusiastic about the project and the opportunity to perform this work in Costa Rica. The water was unbelievably warm, and we all enjoyed the afternoon immensely. We even saw a small stingray!

Hatchery Duty

Thank you, HDS family, for such a great Skype session today. I thoroughly enjoyed all of your thoughtful questions, and it was great to see you all. Tera Dornfeld, the biologist that also spoke with you, enjoyed herself too. She was very impressed with you all! Here is her blog where you can learn more information about the leatherback sea turtles here in Costa Rica. http://theleatherbacktrust.blogspot.com/

I had a couple of people ask what happened to the hatchlings that I showed you today. All hatchlings that are found during the day are placed carefully into a bucket which is then placed in a cool place. As soon as it gets dark, the biologists release them. They make sure to put them on the beach in  approximately the same distance as was the nest (in other words, they don't just throw them into the ocean). This is important because this is part of the imprinting process, and the hatchlings learn what beach to come back to should they grow old enough to lay eggs. The scientists release them at night because there are fewer predators (mostly birds) around at night than in the day on the beach.

Tonight, they will release leatherback, black, and olive ridley hatchlings.
After our Skype session, I was on hatchery duty. The hatchery is a fenced-off sandy area near the beach. The biologist relocate eggs here if a turtle nest is below the tide line. This way, the eggs have a better chance of hatching. The biologist still monitor these nests like the others: they take the temperatures and keep track of how long the eggs have been there.

One nest in the hatchery hatched last night. There are currently three left in the hatchery, but on my watch, no hatchlings emerged. Oh well. At least I got to see a gorgeous sunset.

Leatherbacks!!

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My nighttime turtle watch last night could not be matched! I went out with a young biologist, Jacob, whom I like to call the “Turtle Whisperer.”  Not too long after we started, we got word from the neighboring group that a leatherback nest had hatched, and the hatchlings were headed for the ocean. We hustled over to see this. The extra effort was worth it; hatchlings never cease to be adorable. Being that they are only about 1-2 inches, they are all flipper. And, they are literally bite size. One can see how easy a target for predators they are. Scientists approximate that only 1 in 1000 hatchlings makes it to a full, mature leatherback.

Shortly thereafter on our patrol, we stumbled upon an olive ridley nest that hatched. We noted it, and kept moving. After another hour, we got word from the park ranger on the walkie-talkie that a leatherback had made it to the beach.  Finally!

My heart thumped extra hard as we raced to her location. The park ranger and a large group of tourists were already at the scene. Jacob and I waded through the tourist mob, and he assessed that she was digging her egg chamber. He handed me the egg clicker and the thermal wire, and he instructed me to lie behind her. I lay on my stomach, directly behind her back flippers and watched in awe as she dug. Up close, I could see how incredibly powerful her flippers were, as she gracefully placed one hind flipper in the hole and scooped up the sand to dig deeper. Then, she rhythmically placed the alternate flipper in the hole and did the same thing. After the hole was deep enough, she placed her left hind flipper over the hole. This was my cue that she was about to nest. I moved the flipper to the side and waited. 

 

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Suddenly, 1-2-3, the eggs started coming! I concentrated and clicked as I counted these billiard size balls. The swarms of tourists stepped on me as they struggled to see what I had a front row view of. I placed the thermal wire for later temperature readings in the nest. 20-21-22, eggs counted. Jacob methodically and professionally performed his duties: he scanned her tag and confirmed she was a returning turtle; he measured her; he noted any scars; and he documented her location. 46-47-48, I kept clicking. I worried I was bothering her during this process, but Jacob assured me leatherbacks go into a “trance” when they lay eggs and she is not even aware of us. 63-64-65. My hand shook from holding back the flipper. Then, suddenly the eggs stopped dropping. We stepped back, and she began filling in the hole with sand. Incredible!

We left the beach as she was finishing her nest to make sure we didn’t miss any more turtles. Not more than a few hundred yards, we found more leatherback tracks! Another had come to shore, and she was already laying her eggs! We rushed to get measurements and placed a wire in the nest. Success!

At approximately 2:00 a.m., we found another leatherback and performed the same process. This time I was much more comfortable with the giant on the sand, and I knew what to do. A third leatherback on one night! I truly felt the brilliant stars in the sky were aligned for me!

We wrapped up the data collection and headed home. Arriving back to the field station at 3:00 a.m. made this my latest night yet, but also the most memorable!

Excavation of a Leatherback Nest

Yesterday afternoon, we went with two of the biologists, Jen and Rachel, to excavate a leatherback nest that hatched two days ago. Two days allows enough time for any stragglers to emerge from the nest. The scientists dig up the nests to learn more about the nesting process.

Happy news first met us when Jen started excavating. A single hatchling made it to the surface! Upon further digging, she found one more live hatchling. Jen carefully placed these two hatchlings in a bucket to take back to the field station. A team will release them later at night when the chances of birds not eating them is greater than if they had made their way to the sea at that moment. 

Further excavation continued. Jen dug to the bottom of the egg chamber to find the egg shells and unhatched eggs. She and Rachel then broke open the unhatched eggs to identify the developmental stage of the egg, if any. They analyze these unborn eggs in hopes of predicting nesting patterns and to see if any bacteria infected the nest. On average, only about half of the eggs actually hatch from a nest. This is quite a messy project – and stinky if any nests had been inundated with bacteria or maggots! To be a biologist means rolling up your sleeves and getting dirty!

Leatherback Photos

These are not my pictures, but here are some recent photos of a leatherback taken by one of the biologists. The leatherback finished nesting and made her way back to the ocean.