Sunday, February 08, 2009
Can you tell we had a good time this weekend in Bundaberg? Saturday we drove north (about 4.5 hours) to Bundaberg. We had a date that evening with some as yet unhatched baby turtles!
Mon Repos turtle rookery. One of the largest research facilities studying sea turtles and one of only two rookeries in Australia, the second being in Western Australia. We bought our tickets ($9 - a real bargain!) a week ahead and that meant we were in group 4 of 5. (Lesson here: Call early. Weeks early.) Everyone is told to arrive at the site at 7 PM (Bring rain gear. Bring bug spray. Bring camera. Bring torches (flashlights). Bring a pillow to sit on. (I added the last.)) and as the evening unfolds one group (of 60) at a time is escorted onto the beach. The first group was called right at 7, the second group soon after and I thought we'd have an early night. Then, there was a big pause.
I think I need to back up. Anytime something happens on the beach - a mama turtle comes in from the ocean to lay eggs or a nest of babies begins erupting from the sand - the next group of viewers is called out to observe. It used to be really informal. People would just show up at the beach and follow the scientists around. Then, about 8 years ago the crowd sized topped 2,500 and the majority of turtle-mamas were scared back into the surf without laying their eggs. While I'm sure there was a big voice for just cutting the public out of the picture, the idea of crowd control and public education won out. Now, a limited number of tickets are sold (it must be about 350) and smallish groups are led down one by one to view an event. At this time of year most of the females have stopped laying eggs: only one or two a night show up and that seems to happen after 3 AM. Instead, the babies that have been incubating for about 8 weeks emerge from their buried nests and rush off to begin their lives in the sea.
a. Nesting at Mon Repos: the Australian Flatback Turtle (only found in Australia), the Green Turtle, and the Loggerhead Turtle.
b. Turtle gender is determined by incubation temperature with the critical point being 28.75C (I believe.) Warmer temperatures produce female turtles. Cooler temps, males. (I learned this in grad school. Obviously a worthwhile way to spend 4 years!) The darker sand at Mon Repos is warmer and mostly females are hatching. Eggs laid on the white beaches of the islands off the coast remain cooler thus producing male turtles.
c. Each female loggerhead lays about 200 eggs at each visit and she will lay 5 to 6 clutches at 3 week intervals: about 1,000 eggs/season. She doesn't lay eggs every year or even every other year. It seems to be pretty random with gaps of up to 10 years between egg production years.
d. Number of turtles reaching adulthood per egg hatched: about 1 in 1,000!
e. Lifespan of a sea turtle - excluding the 999 that never reach adulthood - not known though estimated to be 400 to 500 years!
After busting our buts on concrete seats in the amphitheater for more than 3 hours, we were called out to the beach! No lights. No camera flash. No phones. No games. While I would never say it was "bright" on the beach, the moon was mostly full and the sky was clear. (Kevin had already found Orion and, maybe, the Southern Cross during our wait.) We were going to get to observe the release of green turtles that had hatched earlier and had been taken back to the lab for measuring and cataloging. (Green turtles and Flatback turtles are special and all their nests get studied. Only a portion of the loggerhead nests get studied.) There they were in a green plastic bucket trying their best to swim or climb out!
Three guides/researchers pulled out a couple of turtles each and walked among the crowd so we could photograph and touch the babies. I KNEW my digital camera would NEVER produce anything like a reasonable image - flash = whiteout - so I brought my 35 mm camera. Unfortunately, it is getting a bit cranky. Just because you push the shutter-release button doesn't mean that an exposure will be made. Also, I haven't actually tried to take a photo of something small and close with the flash. I have no idea how it will work. This is the problem with film. (I did refrain from looking at the back of my camera after each photograph. I am getting somewhat smarter.) If there is anything to share, I will. Later.
Once we'd all been introduced to the turtlettes, then everyone who had a light lined up one behind the next with their legs spread. They each shined their flashlight at the ground between the legs of the person in front of them creating a tunnel of light leading from the nest site to the ocean. Then, the bucket was tipped
and a hundred baby turtles went flapping at full speed down the beach
and into the surf.
And, way too dark for a photo.
Photo: Turtle photographed when we were snorkling in Hawaii. One of our trip highlights!