Marine Turtles
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[edit] 1 History
Marine turtles have a history that dates back nearly ten million years, having first appeared during the Mesozoic period. They have highly evolved body plans featuring flat fin-like appendages, sturdy enough to still lay their eggs on land. They also have streamlined hard, flat shells to protect them but keep their movements nimble in the water. There are seven species of marine turtles; Flatback turtle (Natator depressus), Green turtle (Chelonia mydas), Hawksbill turtle (Eretmochelys imbricata), Leatherback turtle (Dermochelys coriacea), Loggerhead turtle (Caretta caretta), Kemp's Ridley (Lepidochelys kempii) and the Olive Ridley turtle (Lepidochelys olivacea). Marine turtles are found in all oceans, except those in the Polar Regions. Some species migrate between oceans using the earth’s magnetic current. Marine turtles are threatened species, poachers and predators are pillaging their nests, and their habitats are being degraded by human impact. Many governments and groups have established conservation laws and organizations to protect the marine turtles.
[edit] 2 Protective Legislation
The Endangered Species Act was enacted on December 28, 1973, it is designed to protect threatened species and the ecosystem on which they depend. The Act is enforced and implemented by the National Oceanographic and Atmospheric Administration (NOAA) and the U.S. Department of Fish and Wildlife. Species are divided up between the two agencies with marine species regulated by NOAA and terrestrial and freshwater species regulated by Fish and Wildlife. Turtles, however, are under the jurisdiction of both agencies. Major threats to marine turtles are primarily caused by human impact, such as degradation of nesting sites, becoming by-catch of commercial fishing, and asphyxiation due to marine debris. However, due to current legislation, some species and habitats may not be as protected and conserved as others. According to the Washington Post, under the Bush Administration, many species were denied or were sought to be removed from the endangered species list, rejecting the direct input from biological scientists. The extinction of three species has been attributed to the actions and inaction of Interior Department officials during this time period. Other countries are also fighting for turtle conservation. Out of the seven species of marine turtles worldwide, six of them are found in Australia. These six species are protected by the Environment Protection and Biodiversity Conservation Act of 1999 as ruled by the Parliament of Australia. This act was instilled to protect and promote the recovery of any threatened species or ecosystems. Two of the species of turtle are listed as endangered, whereas the other four are listed as vulnerable. Turtles are also internationally protected by the Indian Ocean-South-East Asian Marine Turtle Memorandum of Understanding (IOSEA) which is “a non-binding intergovernmental agreement that aims to protect, conserve, and recover marine turtles and their habitats in the Indian Ocean and South-East Asia region” (http://www.nmfs.noaa.gov/pr/species/turtles/iosea.htm). Twenty-three countries recognized this intergovernmental agreement in 2005.
[edit] 3 Conservation Challenges
All species of marine turtles have been migrating back to land to lay their eggs on beaches for millions of years. Turtles sometimes come in large numbers to their nesting grounds, usually at night, and over very long distances. After about sixty days of incubation in the nest, the eggs hatch, and the offspring attempt to make it to the water. There are many predators that prey on the baby turtles during this time, such as feral pigs, ghost crabs, sea birds and dogs. Only small numbers of the offspring will make it to reproductive maturity. The eggs are also in danger before they are even hatched. Poachers scavenge the eggs from nesting areas for black market trade, consumption, or as a nutritious feed for livestock. Human poachers are also after the mature turtles as well. The oily meat and cartilage of some turtle species is considered to be a delicacy and can be sold at a high price for turtle soup. Turtle shells are also harvested illegally, particularly that of the hawksbill because of its polished appearance it is very popular for jewelry and other accessories in Japan. Human impact has also strongly affected the turtle populations by habitat degradation and fragmentation.
Marine turtles are also victims of by catch during international commercial fishing. The turtle are commonly caught in driftnets, trawls, set gill nets, purse seines and in long line fisheries. The Leather back turtle is the most common species to fall victim, 94% of by catch records in UK and Irish waters identified this species. Rope entanglement also happens to turtles due to the fishing season, usually along the coastal regions of the United Kingdom and also in the coastal waters of Erie. Of 83 capture records since 1980, entanglement in rope accounts for 36 records, 62% of leatherback by catch for which the method of capture was specified. Recorded mortality was 61%; only 11 turtles have been returned to the sea alive (30.5%) (Pierpoint, C., 2000). There is no data on injuries sustained or death after being released at this time.
[edit] 4 Threats to Nesting Habitats
Many of the marine turtle’s nesting beaches have become popular resort destinations and are a magnet for tourism. The lights of public beaches confuse the female turtles looking for land to nest because the lighted horizon looks like the night sky (P. Castro, M. Huber. p. 180). Other beaches have been commercialized beyond the point of use for turtle reproduction, such as with docks and marinas. These disturbances also destroy the coral reefs, which commonly provide an in-shore shelter and food source for many marine turtles. Marinas and ports are usually constructed by a process call dredging which is a process of basically digging up the waters contents (be it a coral reef or other habitats) and disposing of it at another nearby location. Tourism in general has also caused much of the coral reef depletion. Snorkeling vacationers often break off a piece of coral for a souvenir or sometimes, due to ignorance often bump and kick the coral while swimming causing the polyps and perhaps the colony to die.
Marine turtles have also become a tourist attraction themselves. People often travel to far and/or remote areas to see, photograph and sometimes even swim with them. Many Hawaiian and other tropical destinations advertise marine turtle sightings for vacationers. However, Hawaii has many strict regulations for turtle viewing set in place by NOAA, some beaches have signs posted to “please do not harass the turtles”. Due to the growing concern of endangered species some resorts now offer eco-friendly turtle tours and use it as an educational tool to promote conservation.
[edit] 5 Conservation
Conservation of these animals is very important. The population of leatherback turtles has declined by 95% since the early 1980’s, the amount of breeding females is now only in the hundreds. The leatherback turtle is the most endangered of the marine turtles (P. Castro, M. Huber. p. 180) and is in danger of extinction. In order to further protect the remaining populations, more efficient enforcement and monitoring methods should be established to help end or hinder the black market sale and poaching of marine turtle species. More education for tourists could also contribute to the well being of the turtles. Marine turtles have become victim of overexploitation due to their beauty and fascinating lifestyle.
Marine turtles have fallen victim to many threats and disturbances. Their decline in population is greatly due to habitat degradation and direct human impacts. The conservation of these species is very important and, due to their declining populations, more action needs to be taken. There are many policies and organizations that help to protect marine turtles specifically; due to their importance as a staple species, they are considered a priority for conservation. Marine turtles are an irreplaceable resource of ecological services; they are an important component in many consumable marine markets (bivalves, etc.) and are a large contributor to ecosystem services due to their long life and wide migratory patterns.
NOAA Fisheries and the Office of Protected Resources are helping with the conservation of marine turtles with the The Indian Ocean – South-East Asian Marine Turtle Memorandum of Understanding (MoU). This memorandum is a non-binding intergovernmental agreement that aims to protect, conserve, and recover marine turtles and their habitats in the Indian Ocean and South-East Asia region. The agreement falls under the auspices of the Convention on the Conservation of Migratory Species of Wild Animals (Article IV, para. 4) (NOAA). Marine turtles have been around a long time, and we should help to keep them here for many years to come. Turtles are an important species and their protection subsequently will protect other species due to their wide range of migratory patterns and habitats.
The World Wildlife Fund, in partnership with The Ocean Conservancy, supported the Marine Turtle Conservation Act and in 2004 it passed into law. This act grants up to five million dollars a year for projects pertaining to the protection of both marine turtle habitats, as well as their nesting grounds in foreign countries (WWF. 2004). This will help promote habitat restoration and the overall well being of this very important species.
The “Nairobi Declaration”, in May 2002, was a meeting in Nairobi to discuss and make a comprehensive conservation plan. They made sure to attend to the issue of by-catch in industrial fishing operations worldwide. To develop conservation methods it was decided to involve the local communities in both the methods and the implementation of the activities, this was a large contributor in conveying the message of conservation. This method of making the public aware of what is happening can be a very good approach. This can help develop a following and help with environmental stewardships.
Population monitoring is a crucial part of marine turtle conservation. However, according to an article in Biological Conservation, this can be difficult to study due to the turtle populations being widely dispersed during the breeding season, so the data can be sparse. Therefore, nesting site monitoring is a much more common program for researchers. With these studies, it has been found that nesting has decreased with the Green and the Hawksbill species. However, there does seem to be some species that are more resilient to exploitation pressure (Broderick et al. 2008). Effective nesting site conservation has included using wire screen to place over the nests. This technique has resulted in lower predation rates, and the number of nests laid increased for each species on these protected beaches (Antworth R et al. 2006).
Further conservation techniques could include stronger regulations from both federal fisheries policies and the Endangered Species Act. More highly trained fishermen or more marine observers could help decrease the amount of bycatch. The conservation of these animals is very important, especially since they are endangered species. It can be amazing what the general public can do to assist and do their part to help with conservation methods. With this help, agencies can help enforce the law while everyone else can be aware of what their actions can do. This education may help reduce the amount of by-catch accidents by helping to eradicate and control the careless and ignorant behaviors that result in the loss of marine turtle lives.
[edit] 6 References
Castro, P and Huber, M. Marine Biology. New York: McGraw-Hill, 2007.
Pierpoint, C.. “Bycatch of marine turtles in UK and Irish waters” Joint Nature Conservation Committee. Report 310. 2000. <http://www.jncc.gov.uk/page-2330>
Digest of Federal Resource Laws of interest to the US Fish and Wildlife Services, “Endangered Species Act of 1973” 18 January 2009 http://www.fws.gov/laws/lawsdigest/ESACT.html
Eilperin, Juliet. “Since ’01, Guarding Species is Harder” Washington Post. 23 March 2008: Page A01.
Gardner, Emily (M.S.), “Green Sea Turtles” Hawaii Department of Education Accessed on 18 January 2009. http://www.earthtrust.org/wlcurric/turtles.html
Groom, M, Meffe G, and Carroll C. Principles of Conservation Biology. Sunderland, MA: Sinauer Associates, 2006.
“Marine Turtles”. Marine Species Conservation. 2007. Australian Government: Department of the Environment, Water, Heritage and the Arts. 28 Jan. 2009 http://www.environment.gov.au/coasts/species/turtles/index.html
National Oceanographic and Atmospheric Administration “Endangered Species Act” NOAA Fisheries: Office of Protected Resources. Accessed on 16 January 2009 http://www.nmfs.noaa.gov/pr/laws/esa/
National Oceanographic and Atmospheric Administration “Marine Turtles” NOAA Fisheries: Office of Protected Resources. Accessed on 16 January 2009 http://www.nmfs.noaa.gov/pr/species/turtles/
National Oceanographic and Atmospheric Administration “Indian Ocean-South-East Asian Marine Turtle Memorandum of Understanding” NOAA Fisheries: Office of Protected Resources. Accessed on 30 January 2009 http://www.nmfs.noaa.gov/pr/species/turtles/iosea.htm
NOAA Office of Protected Resources “Hawaii Viewing Guide” Accessed on 16 January 2009. http://www.nmfs.noaa.gov/pr/education/hawaii/
Conservation of Migratory Species. Memorandum of Understanding Concerning Conservation Measures for Marine Turtles of the Atlantic Coast of Africa. 2004. http://www.cms.int/species/africa_turtle/AFRICAturtle_bkgd.htm
NOAA: Office of Protected Resources. Accessed March 2009. http://www.nmfs.noaa.gov/pr/species/turtles/iosea.htm
WWF: Press Release Marine Turtle Conservation Legislation Signed into Law WWF and the Ocean Conservancy Praise Unanimous support of Act. July 7, 2004. Accessed March 2009. http://www.worldwildlife.org/who/media/press/2004/WWFPresitem719.html
Frazier, Jack. 1999. Community Based Conservation. http://nationalzoo.si.edu/ConservationAndScience/AquaticEcosystems/SeaTurtles/ Antworth RL, Pike DA, Stiner JC. 2006. Nesting ecology, current status, and conservation of sea turtles on an uninhabited beach in Florida, USA. Biological Conservation. 130(1).
Jackson A, Broderick A, Fuller W, Glen F, Ruxton G, Godley B. 2008. Sampling design and its effect on population monitoring: How much monitoring do turtles really need? Biological Conservation. 141(12).
Broderick A, Frett G, Godley B, Gore S, Hastings M, McGowan A, Pickering A, Wheatley D, White J, Witt M. 2008. Down but not out: Marine Turtles of the British Virgin Islands. Animal Conservation 11(2).
Seminoff, J and Shanker K. “Marine turtles and IUCN Red Listing: A review of the process, the pitfalls, and novel assessment approaches” Journal of Experimental Marine Biology and Ecology. 356. 2008. pp. 52-68.
