There was a lot of "Horsing Around" at Grotto Beach, San Salvador, Bahamas. See other beautiful phenomena from the Bahamas.
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Sea Turtles: Different Species and Characteristics
ÒThroughout the world, sea turtle populations are disappearing. This is a flagship crisis in marine biodiversity, and the repercussions will reverberate throughout marine ecosystems and the Biosphere as a whole" (Wallace). Sea turtles have been around for millions of years ever since dinosaurs were roaming the Earth in the Mesozoic era. Throughout their existence, they have developed numerous characteristics and adaptations becoming the modern day sea turtles that are roaming our oceans. There are 8 different kinds of these reptiles alive today whose traits and habits vary between species. Humans tend to know much about sea turtles however recently we have not done our part to keep them safe and prosperous. Each one is on the endangered species list or threatened and with a little education and conscious effort we can help to build them back into a healthy community.
On our trip we are lucky enough to possibly see up to 5 different kinds of sea turtles, which include: the Green, Loggerhead, Leatherback, Kemp's Ridley, and Hawksbill turtles. All together there is great debate about whether there are actually 7 or 8 different species of turtles today. With my extensive research there is enough information about 8 kinds and that is what I will continue my paper with. In addition to the above 5 there are also Black, Olive Ridley and Flatback turtles. The physical appearance of each is distinguishingly different along with the subtle differences among males and females. They are all characterized by their streamline shells and nonretractile limbs and head. The largest of the turtles is the Leatherback which is approximately 149 cm long and the smallest is the KempÕs Ridley which is less than half that size at about 65 cm long. The weights of turtles therefore tend to be different as well amongst species. The smallest KempÕs Ridley turtles sometimes will not even reach a hundred pounds. The Leatherbacks are the biggest ranging weights from four hundred and fifty to the heaviest one recorded at two thousand and nineteen pounds. The size and weights do differ much which makes it easier to distinguish each type from another. The males and females in comparison look a little different so that people are able to tell them apart without a DNA test. They do not differ externally until they have reached maturity however. In most species the differences are that the males have longer thicker tails that allow them to hold on to females when breeding and also longer claws that assist in mating as well.
Sea turtles have different habitats that they live in throughout hatching, juvenile and adulthood life. They are all found in warm and temperate seas around the world. Adult turtles live in the deep ocean waters, coastal waters, bays, lagoons and estuaries. The teenage turtles live in about the same region however the period between their hatching and early adulthood is not very well known and called the ÔLost YearsÕ. ItÕs too hard for humans to track these creatures, so little is known of their whereabouts during this stage of their life. They venture back to their breeding ground waters at some point to make it home there. The babies are always born on land. The exact places vary amongst types of turtles whether it is a beach in Florida or one of the many islands that scatter the world. It is essential to know that turtles are oxygen breathing animals and are able to live on the land as well as the ocean for great amounts of time. They are able to swim in the underwater ocean for hours at a time without coming up for a new oxygen supply. Female sea turtles and new borns are the only ones that make it to land. Once males have ventured off into life they will not try to rest on land again.
Breeding habits tend to be unanimously similar between the species. The age of sexual maturity is anywhere between 20 and 50 years old for most turtles. It is believed that this age is reached once the size of their shell is big enough to reproduce. Once they get to this size most turtles will stop growing but some continue for years. Mating occurs just a few weeks before nesting season and numerous males may court one female. The fertilization occurs internally so one batch of eggs could potentially have been produced due to a mixture of different males. The nesting behavior is basically the same amongst species except for the fact that the Leatherback turtle lays eggs in colder months and all others do some when it is warm. When the female turtles know that it is time to lay eggs they will go onto the beach shores during the nighttime and dig a hole big enough for her to lay in and deep enough to keep the eggs buried until they hatch. On average a female will lay between 50 to 100 eggs at one time. Per nesting season however they are able to lay up to 9 clutches of eggs. Because this birth process is so stressful after a breeding season the females will take a few years off before they start to do the birth thing again. They know what beach they have gone to to nest and usually continue to go back to the same place each time. Around 50 days later the babies will hatch and be on their own to make it safely to the ocean and to adulthood. An interesting fact is that the sex of the turtle is determined due to the outside temperature where their nest was made. Cooler temperatures produce males and warmer will produce females. Like previously stated only one in a thousand baby turtle will make it to adulthood due to an abundance of obstacles and predators that they face. Because males donÕt come ashore and there is a ÔLost AgeÕ it is very difficult for people to know close population statistics for these creatures.
Sea turtles unique behavioral traits and adaptations help distinguish them from land turtles. For starters the most obvious is that they are not able to retract their head or limbs into their shells. They are equipped to be great powerful swimmers due to their long paddle like flippers. The biggest of the turtles can get to speed up to 5 miles per hour cruising the ocean currents. They are cold blooded reptiles and due to this they have a really slow metabolism. This allows them to stay underwater for long periods of time. There is a statistic that approximately 9 minutes elapsed between heartbeats on these big turtles. They are able to comfortably live in sea water without a need for a fresh water source. They get enough water through their diets and also have a salt gland near their eyes where they release salt from inside their bodies. When females are nesting they let the salt out and it looks as if they are crying. All of these adaptations that make them successful in the sea are what impairs them on land. They are slow and awkward ashore making it a threatening environment for them. All of the 5 senses are interesting as well. They do not have actual physical ears however they do have ear drums and can hear low frequency sounds and vibrations. They are able to see well in the water but when on land they cannot see very far and rely on light and instinct to guide them. They are sensitive to touch on the softer parts of their flippers and shell. Smelling abilities have been studied and realized but it is believed that they have a narrow list of what they are able to smell. It is hard to say how they taste and how their glands work.
Sea turtles diets and eating habits are extremely similar throughout species mostly varying due to the age of the individual turtle. The jaw size and arrangement is a key to understand the types of foods that they eat. Depending on species and age they can be carnivores, herbivores or omnivores. The Green turtle is the only one that remains an herbivore in adulthood. It feeds on sea grasses and algae. They are also odd in the fact that when they are young they eat mostly meat to grow big and strong and then switch to their herbivorous diets once they become an adult. The rest are omnivores in wild life but can be kept on a carnivorous diet in captivity. An assortment of things will satisfy these creaturesÕ appetites. They are able to pick from sponges, shrimps, squid, jellyfish, crabs and underwater vegetations. Just so we know, the ones we will see in the ocean are not interested in trying to bite us for a snack!
Migration behavior and habits also differ amongst species but it seems to be one of the most studied and questioned traits of sea turtles. Depending on type, they can travel only a few miles up to thousands. This migratory journey begins as soon as the young turtles hatch. They use instinct and the reflection of light on the ocean to guide them into the waters. Once in the waters they fend for themselves and this is the period known as the ÒLost YearsÓ that we do not know too much about. ItÕs believed that the young turtles swim around inter tidal areas and eat off of algae animals and crustaceans. Then they embark again on their journey as adults coasting along with the ocean currents and trade winds. Eventually they make it back to the same Ôhome baseÕ that have bred and grew up with. People have been tracking sea turtle migration since around the 1980s. It is difficult for humans to accurately watch them throughout their whole life because once they are hatched they are too tiny for detection gear and would grow out of it. We are curious about the age and behavior of these ancient reptiles. There are many different tactics that can be used to try and track them however. Some types include: flipper tagging, radio, sonic, and satellite tracking and a source talked about a new harness that does not physically hurt the turtle and is supposed to fall off after a few months. We hope to figure out the exact ages of turtles but we just started these questions in the 80s so we have not yet seen a turtleÕs full life in just 30 years. The life span of turtles is one of those facts that coincide with the wonders of migration. People are not able to track an individual turtle from the time of birth all the way to maturation. The pure fact that only one out of one thousand laid eggs will even make it to an adulthood life is a depressing thought. This leads to the current problem that each of these species is threatened.
All of these species are currently on the endangered species list or considered threatened around the world. They have many natural predators that cause fatalities and also our human influence has caused problems with population as well. Adult predators are mostly sharks and some killer whales will try to eat them as well. Babies and eggs are the most vulnerable to natural threats from fish, dogs, raccoons, seabirds and other land animals and bigger sea creatures. Human influence has affected their growth by the pure fact that we mess up there nesting environment by noise, light and growing tourism. The females get confused and will not nest or could even lose their eggs because they are scared. Boat propellers and human trash affect the older turtles in the ocean. Also in some countries people eat these creatures and try to collect their unhatched eggs. Natural disasters like hurricanes and other weather effects can destroy turtle habitats forever. The biggest disease that they can get is fibropapillomas which was talked about in the ÒEnchanted BraidÓ. These are huge tumors that develop on their scales and can completely consume the turtle and weight them down while swimming. There are a lot of obstacles that these reptiles must face in order to live a full life however there are things we as humans can do to prevent this.
Earth is a beautiful creation that encompasses a plethora of ecosystems, creatures and landscapes that characterize our world today. Sea turtles are an essential key part in life and it is crucial that we, as humans and the most influential unit, do our part to preserve their communities for decades to come. All that it takes is a little education and awareness of what our actions do to our surroundings. People need to go out to the beaches and mark off the nesting areas so that people do not mess with the nests and produce many babies in captivity so we can make sure they will never run into extinction. There have been many acts passed through congress to save them and have humans be more sustainable. There are wildlife reserves and zoos that work every day to promote a better way of life for these poor creatures that do not have a voice to do it themselves. They have made it this far in history and we should not be the reason why they die off. ItÕs simple and easy to live at piece with our environment all that it takes is a little effort to do the right thing.
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Works Cited
1.Satellite tracking of sea turtles: Where have we
been and where do we go next?
B. J. Godley1,*, J. M. Blumenthal1, 2, A. C. Broderick1, M. S. Coyne1, 3,
M. H. Godfrey4, L. A. Hawkes1, M. J. Witt1
2. Predicting the Impact of Sea-Level Rise on Caribbean Sea Turtle Nesting Habitat Conservation Biology, Volume 19, issue 2 (April 2005), p. 482-491
3. The Ecology and Migrations of Sea Turtles, 6 The Hawksbill Turtle in the Caribbean Sea BY ARCHICE ARRH,~A ROLHDI RTHA,N~D LARRYO GREN~
4. Foraging ecology and nutrition of sea turtles By Karen Bjornal
5. Eckert, Scott, Dean Bagley, Stacy Kubis, Llewellyn Ehrhart, Chris Johnson, Kelly Stewart, and Duane Defreese. "Internesting and Postnesting Movements and Foraging Habitats of Leatherback Sea Turtles (Dermochelys coriacea) Nesting in Florida." 5 (2007): 239-48. Academic Search Complete.
8. "The Long Migration of Sea Turtles." Oceana. 2008.
9. "Sea Turtles." Http://www.seaworld.org/animal-info/info-books/sea-turtle/conservation.htm. 2009.
10. Wallace, Nichlos J. "Sea Turtle Restoration." 15 Apr. 2002.
11. "Sea Turtle Outlines." EuroTurtle. 2006.
12. ÒSea Turtle Fact Sheet Index." 16 Feb. 2005. North Florida Field Office.
13. Lutz, Peter, John Musick, and Jeanette Wyneken. The Biology of Sea Turtles. CRC P Inc., 1997.
14. Davidson, Osha. The Enchanted Braid. John Wiley & Sons Inc., 1998.
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