Monday, July 16, 2018

National Parks: Padre Island National Seashore -- Turtles Part 2

The Kemp's ridley sea turtle is most critically endangered sea turtle. It is also the smallest and rarest. I've been to enough presentations and read the materials to summarize the history of this species:

Once, Spanish conquistadors reported having to lower their sails as to not crash into the massive herds of Kemp's ridley sea turtles that seem to swamp the Gulf of Mexico. But no one knew where they nested. For a long time, it was thought that these turtles were probably the infertile hybrid of other turtle species. But then fishermen found that these turtles were pregnant with eggs. So they were a species, but no one knew where these mysterious turtles nested.

In 1940s, Architect Andreas Herrera, who regularly visited Mexico and flew his own plane, was hunting down leads of where this turtle was sighted emerging from the sea. In the summer of 1947, he made an incredible discovery. At Nuevo Rancho beach in Tamaulipas, Mexico, he witnessed thousands of these sea turtles emerging from the sea. He recorded the event on film. He tried to spread the word to the scientific community and leaders to do something to protect the sea turtles.

He was concerned that in addition to seeing the thousands of sea turtles, he recorded many people digging up the eggs, flipping over the big turtles, and taking the turtles to butcher for meat and to eat and sell their eggs, supposedly for aphrodisiac purposes!

By the 1960s, scientists finally discovered the film and raced down to see the Nuevo Rancho site. The film recorded an estimated 45,000 sea turtles in 1947. When the scientists got there in the 1960s, the population had plummeted to only 700! Poaching, unsound fishing practices, and other factors had destroyed the population and put them on the brink of extinction!

Emergency action was taken by many concerned people to save the species. And so, the work began to save the Kemp's Ridley Sea Turtle. And that work continues to this day. And though the turtles are slowly recovering, they still need our help. We can be better people and help save the species.



The nets and streamers keep the predatory birds, like pelicans and especially those filthy flying rats--seagulls--from swooping down to eat the little hatchlings. We are told beforehand by the park rangers not to wave our hands to chase away the seagulls. The seagulls have learned from watching humans that the waving of hands means that there is food to be taken! That's why there are signs posted not to feed the animals, because then, animals like seagulls will lose their instinctive fear of humans and start targeting people for food, swooping down to steal them! Even worse, some human food is very bad for birds! So please listen to the park rangers and stop feeding the damn seagulls!


Dr Donna Shaver and the team release the hatchlings right as the sun rises, to help the hatchlings imprint on the beach and learn to come back to this location for nesting. Notice how the team wears gloves to keep their scent from interfering with the imprinting process. We are asked not to wear white, as the hatchlings may mistake the bright white clothing as the sun and get disoriented, heading towards the white clothing instead of towards the sea where the sun is rising. We are also asked not to bring any food, as that may attract predators, like coyotes and seagulls, which prey on hatchlings.



Kemp's ridley sea turtles are the only species that nest in the day. The females lay 50 to 100 eggs in a clutch. And in the late spring to summer season, the females may lay two to three times, then take the following year off. When the turtles lay their eggs, they enter a trance state, where they tune everything out. This is the time the scientists take measurements and make observations of the turtle. It is also when the turtle is most vulnerable, especially since they like to nest in the tracks of soft sand made by vehicles. And they are prone to get run over because they blend well with the sand and they won't get out of the way. That's why teams patrol the beaches to spot and protect nesting or injured or ill turtles.


As with other reptiles, the temperature in the nest determines the sex of the hatchlings. Higher temperatures lead to more females. So the eggs near the top, close to feel the heat of the sun, are females. The eggs towards the bottom turn out to be males.


Once they grow up to be adults, the females will return to lay their eggs. But the males will live our their lives at sea.


The team knows that the hatchlings are ready to hatch out of their shells by their activity. In their special sand incubators, the hatchlings start to move towards the surface, from a depth of a foot or so. The first hatchers create enough movement to cause the sand to form a divet, a hole, in the top of the sand. That signals that the frenzy, the act of crawling out the sand and towards the sea will begin soon, at the next sunrise. And since these are reptiles, cold blooded--unable to regulate their own body temperature, they need the warmth of the sun and a little time to get moving, and some late hatchers take a bit more time to wake up and warm up to get moving.

These are the little ones the park rangers bring around to show us. And after a little time warming up in the ranger's hands, the hatchling is ready to join their siblings all ready in or headed towards the sea. Then they are released and guarded as they make their way toward the waters of the Gulf of Mexico.


Please, No Flash Photography. The bright light disorients the hatchlings and ruins the imprinting process. Cute little babies, aren't they?




It takes 10 to 12 years for the baby hatchlings to mature. So, it will be at least 10 long years before we see the females from this clutch return to nest on these shores. Let's hope these babies all survive and thrive to adulthood.


Have a safe journey, little hatchlings! Y'all come back, now, ya hear!?!



7 comments:

  1. Very nice piece. But I got a good chuckle of the close up of the little one, looks cranky, being held. He has the look of " Ok...can you please put me down now...my crew is leaving."

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    1. Maddie, He does look cranky! He's one of the late wakers, and he's a little grumpy at having to meet all these visitors so early! He just wants to get in the water and get some breakfast!

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  2. All the insanity in the news these last couple of days made me miss these entries (pts 1 and 2)! Glad I caught up, sugar. We have the Loggerhead Sea turtles out here on Tybee Beach. Both are stories of survival and our attempts to help save species we're decimated through our own ignorance! (Around here it's "Keep Them Damned Lights Off" on the beach season when they're hatching!) xoxo

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    1. Savannah, That's awesome how people remind the public to turn off the lights during hatching season so the hatchlings know to swim for the sea reflecting the stars and moonlight. Loggerheads are neat! I've seen a few in the water just swimming along! I'm glad the locals are protecting this marvelous species.

      It may be small steps and we definitely need to do more, but at least we are taking corrective action to clean up our mess and save the species we've harmed thru our carelessness and ignorance. That's the one good thing about us humans. There are still a few of us who do the right thing and care enough to make the world a better place.

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  3. Aw. More cute little turtles!
    I had a read of the website and was fascinated by the methods and effort that goes into assisting these baby turtles, especially transferring the nests to secure sites. It did make me wonder if, in a few years time, there might be too many turtles coming back to the same beach to lay their eggs?

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    1. IDV, In the lecture, the park ranger told us that nests left in the wild have a 59% survival rate--predators dig and eat eggs and the emerging nestlings. In the protected sites, there's an 89% success rate of hatchlings making it to the sea. The babies live by hiding on the sargassum seaweed floating in the Gulf waters.

      About 125,000 hatchlings are released in North America (a small fraction in Padre Island National Seashore, the majority from Nuevo Rancho, Mexico). Only 1% of that number will survive to adulthood and be able to reproduce. In 2010, there was a sudden unexpected drop in the nesting. The Horizon offshore drilling accident happened. But the drop in population occurred before Horizon. And scientists are still trying to figure out what caused the population decline. But Horizon did have an impact that lasted for years. We have evidence that many turtles die from starvation and complications from eating plastic bags--they look like jellyfish or food the turtles eat. So pollution is still a major factor in their decimation.

      Only in the last year, 2017, has the population seem to recover, with the most nests ever found (219 in the park, 353 overall in the state). This year is the second most, with 200 found so far state wide, 100 on the National Seashore, the season for nesting continues all summer.

      In 1947, Architect Herrera filmed an estimated 45,000 Kemp's Ridley sea turtles emerging from the sea to nest at Nuevo Rancho, Mexico in One Day. By the 1970s, only 700 nests were found All Season! Emergency action was taken to save the species. Yet even in the 1990s, many said that it was too late, the species was going extinct, as none of the head started and marked hatchlings had ever returned after being released in 1986.

      Then in 1996, two marked turtles were discovered nesting on the National Seashore, proof that the efforts were working, that the species could be saved! And from those two nests, we arrive to the two hundred of last year and the one hundred so far this year on the National Seashore. Good news. Even better news, Nuevo Rancho reported over 8,000 nesting turtles in one day at the beginning of summer, the most ever nests in a single day, since the program started in the 1970s! So fingers crossed that the fragile turtle population keeps recovering.

      But it still breaks my heart to realize that maybe only one or a few of the baby hatchlings crawling to sea will ever survive to make it back to shore in 10 to 12 years. I wish more could be done to ensure more babies live to adulthood to return to nest.

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