Wednesday, August 21, 2019
A Case Study Of Sea Turtle Conservation Environmental Sciences Essay
A Case Study Of Sea Turtle Conservation Environmental Sciences Essay Sea turtles are being caught throughout the world even though these endangered species are illegal to hunt them. Most of these sea turtles are being hunt down for food. These turtles are considered a source of fine dine in most parts of the world for centuries now. For instance, one Chinese text that dates back to the 5th century B.[1] describes marine turtles as exotic food. Several coastal countries harvest these sea turtles and use them as a major source of protein in their everyday food. These people also use turtle eggs in their food. Certain other countries like Mexico use these turtles in boots Certain species of sea turtles are hunted down for their shell. For instance, one of the species called hawksbill sea turtle produces Tortoise shell which is a traditional decorative ornament in Japanese and Chinese culture[1]. Similarly the Ancient Greeks and Romans used turtle scutes to make ornaments and jewellery for the elites. The Moche tribe of Peru worship turtles along with other sea animals. Sea turtles have been enormously depicted in Moche arts[2]. Tropical beaches are kind of made safe by the sea turtles that are immune to jelly-fish toxin and frequently eat them. Green sea turtle are few sea animals that feed on the green sea grass. Certain sea turtles graze on the sea grass under the sea that is supposed to be kept short in order to maintain the health of the sea[3]. The sea grass bed is the developmental and feeding ground for several sea animals. Loss of sea grass bed can result in lower levels of food chain and loss of several sea life and endanger countless marine species[3]. The following are the eight endangered species of marine chelonians; loggerheads (Caretta caretta), hawksbill turtles (Eretmochelys imbricata), leatherbacks (Dermochelys coriacea), kemps ridley turtles (Lepidochelys kempii), olive ridley turtles (Lepidochelys olivacea), flat-back turtles (Natator depresses), green sea turtles (Chelonia mydas), and the black sea turtles (Chelonia agassizii). These endangered species have numerous biological features as well as in their life cycle which makes them chiefly susceptible to human interference[4]. Usually, the majority migrates between feeding and nesting grounds, have a longer life span, nest on semi-tropical and tropical beaches, breed seasonally, have bulky clutch sizes, and have elevated mortality before adulthood. The sea turtle population size and dynamics are not just affected by one anthropogenic cause rather there are numerous threats both on shore and out in the sea that is responsible for the declining population size in almost a ll the species[3]. The main consideration is commonly given to in shore and beach conservation. This paper will evaluate the present stressors on sea turtle populations from the standpoint of nesting beach associated conservation including instability to nesting females and to clutches and hatchlings. This paper furthermore will comprise an inspection of the management methods to tackle with decreasing populations in nesting areas, including management normally employed in developed countries[5], management with the public education and participation in third-world countries, and management of pre-nesting females present off-shore, who are frequently caught as bicatch during fishing. During breeding and nesting periods the sea turtles gather off shore at the beach and thus are easily accessible to the human populations. This is the time when these turtles can be either positively or negatively affected by the human population. Disturbance to nesting females is the primary hindrance in nesting beach conservation projects. Pedestrian intrusion and under education concerning the suitable manners to interact with nesting females is typically the main threat, and in severe cases such as in developing countries, simmering is extremely persistent and hard to manage, but is generally uncommon in developed countries[4][5]. Human interference can cause females to get lost inland and become entrapped in bushes and die from dehydration and stress, run over by cars, and potentially come in contact with dangerous and toxic materials and protract life threatening injuries. Similar consequences can result from light induced disorientation[6]. The female turtles have an innate tendency to orient themselves to the brightest horizon which is always the sea, but lights from buildings and cars and other kinds of human interference can make them disorientated and crawl towards what can be called as potential hazards. Human interference in addition may lead to abandoned nesting attempts, as the females may find the beach inapt and dangerous, probably taking humans as predators that may eat her clutch or cause her injury. Furthermore, beach furniture, cemented pavements, roads and similar other obstacles can interfere with the normal biology of sea turtles and cause the female turtle to find the beach inapt and insecure for nesting attempts[7][8]. There have been reports of beach furniture and other similar objects being the cause of death for female turtles. The fact that female turtles frequently false crawl has been documented and observed to be true[8]. The female turtle crawls on the beach and then make a U turn to crawl up again and back down, this is a way to reassure that the beach is suitable and secure for the final nesting. On the less disturbed beaches there are generally identical amounts of nesting and non-nesting appearances, where on extremely disturbed beaches non-nesting emergences can be several times higher than nesting appearances[2]. The outcome of high aborted nesting trials is not known, it has been implied that these females typically find a close by beach which is more apt, or probably reabsorb the eggs[1]. The clutch and hatchlings are generally very vulnerable to damage from human interference. Apart from human interference the clutch and hatchlings are also susceptible to natural predators, environment and natural mortality[9][4]. No matter how good a researcher might be, if he or she is not well aware of the needs and risks of these clutch and hatchlings, they can significantly decrease the nests success. Several of the threats on concerned beaches comprise beach tools flouting or revealing eggs, human pests like dogs, cats, raccoons and rats digging up eggs. Artificially constructed barriers and constructions on the beach can lead to the drowning of eggs, the hatchlings can get attacked by fire ants, rà à µlocation of thà à µ clutch outsidà à µ thà à µ safà à µ 6-hour post-dà à µposition window, rotating à à µggs during rà à µlocation, and entanglement in holes and ruts[10]. The threats discussed above are besides the natural threats like predators and other wild dogs and cats that can potentially attack the hatchlings, and the environmental effects of bad nest position leading to below optimum moisture, plants, sand resolution, aà à µration, tà à µmpà à µraturà à µ, and vulnà à µrability to sà à µasonal interference such as hurricane storm surge[8][9][10]. The most rational method to improve and advance marine sea turtle life is by managing the nesting beaches. These beaches are reachable to researchers and a basis of high mortality for hatchlings and adults. Nest management programs are one of the most widespread and effectual ways of enhancing survival, particularly in adjunct with legislation and community cooperation[1]. There are a number of programs that are completely community based, where marine turtles are an important part of the domestic financial system, custom and food source, and the sustainable management of the animals is a source of income for the community and a safe haven for marine turtle conservation[10]. [5] The majority of the programs in the developed countries are concerned with the safety of the nests and the beaches from intrusion and human interference. Besides this other management strategies deal with the gathering of females off-shore during the nesting period, where leisure and fishing ships cause the death of females from accidents, entrapment in fishing lines, and drowning in trawl nests[4]. The nesting beach program of Sarasota n Florida is a typical model of the developed nesting beach program. During the nesting season, the nesting beaches are constantly patrolled. A documented track is kept during these patrols for nesting and non-nesting emergences[4][6], in addition the nests are marked off with wooden stakes and flags in order to keep a track of nests and at the same time make the public aware of the nests presence. Areas with high risk of predation, human interference or any other similar hazards have a deeply rooted iron cage around the nests to protect the emerging hatchlings from these hazards. The wooden stakes used to mark the nest have a detailed information tag that includes the date at which the nest was laid along with the nest number and GPS coordinates in case the original stakes become lost due to any reason. Records are kept concerning any abnormal tracks or nests made by females, as they are typically a sign of interruption or disorientation from human sources. The nests are under surveillance all through the season for damage caused by delinquents, flood, ant invasion, predators, and damage caused by storm surge[10]. The contents of the clutches are sorted out 24- 48 hours after they have hatched. Alive hatchlings are brought to the aquarium to provide required care and are kept there until the end of the season before releasing them. The amount of dead partially hatched hatchlings are calculated from the remains of the shell[9]. Nest success is calculated for every nest as the amount of hatchlings that effectively hatch and leave the nest; regrettably post-hatch predation can frequently not be calculated and included in the measure. The nest success is used to evaluate the comparative success of the conservation methods, and to recognize main risky and low success locations and may begin the probable repositioning of nests in prospective years. One of the significant things to be considered across the management region is the nests to non nesting emergences ratio. This is important due to the fact that areas that diverge from the anticipated 1:1 ratio may either be extremely disturbed as females terminate most nesting attempts, or an extremely flourishing beach with a high amount of nesting emergences[5]. These beaches can then be prioritized into beaches which need extreme consideration and regulation due to extreme interruption, or need to be conserved so that extremely successful beaches are not lost to development. These management programs and their enforcement power is frequently supported by federal and state legislation that enforce heavy penalties and jail time to people who directly or indirectly contribute to the interruption of a sea turtle, its nest, or hatchlings. Infomration of this program was acquired from personal experience at Mote Marine Laboratory, Sarasota, Florida, 2005, whilà à µ corrà à µspond ingly dà à µscribà à µd programs includà à µ onà à µ in Brazil, in diffà à µrà à µnt arà à µas of Florida (Johnson and Eckhart, 1996; Antworth, et al., 2006), and in Greece[5][7][8][9]. Community conservation is regularly a very booming in terms of economy conservation program in third world countries, as sea turtles are very imperative for the local economy, custom and as a food source[1]. Locals are commonly willing to contribute and operate their own programs as these programs significantly benefit the community. An example of a extremely flourishing program is in Ostional, Costa Rica, which is the sight of one of the worlds largà à µst mass nà à µsting of thà à µ Olivà à µ Ridlà à µy sà à µa turtlà à µ. When the fà à µmalà à µs waiting off shorà à µ arà à µ cuà à µd to begin nesting locals consider the cue is correlated to the lunar cycle- the local group of turtle[2][3][6] watchers and visiting rà à µsà à µarchà à µrs takà à µ tourists to vià à µw nà à µsting for a fà à µÃ à µ, which is an important basis of income for the villagers. At times the turtles start digging up other turtles nest to deposit their own due to the high density of nesting females in the vicinity. Due to the fact that the life span of dislodged eggs significantly reduces 6 hours post deposit the local villagers are permitted to collect the dislodged eggs and sell them in the market at a price of a chicken egg to avoid black market demand. Some of the locals also help researchers and participate in caging clutches at risk from predation, and teach tourists about the anthropogenic and natural risks to sea turtles. The offshore gathering of the nesting females is a threat since these females are at greater risk to accidents through offshore human. Even though the traffic off-shore from nà à µsting bà à µachà à µs is difficult to control, the development of the turtle excluder device for fishing vessels has reduced the number of drowning deaths of sea turtles in nets. In Bahia Magdalena, Mexico, numerous turtle carcasses for numerous species of marine turtle are found decaying all along beaches inside the town, which are typically due to the bi-catch from off-shore trawling, if not from plundering. The turtle excluder device is an add-on to trawl nets that let turtles to get away through a huge trap door in the back of the net, and has saved countless nesting and foraging turtles from drowning. Regrettably in certain parts of the world, such as in Mexico and India, there are enormous deaths due to trawling around the nesting period, and the local fishermen decline to utilize the excluder devices, in spite of being offered without any cost, since they believe they might lose their catch when the turtles exit the net. In fact only few fishes are lost through the trap door and moreover it will save them more money since they wont have to restore or repair the damaged nets caused due to entangled turtles[1]. Another source of mortality is the longline fishing. The sea turtles can potentially take the bait and become entangled in longlines, although, the introduction of circular hooks have helped reduce the mortality due to specific cause. Lately, numerous nesting beach programs globally, have been tagging nesting females through satellite[6][7]. This way they can keep track of the nesting females position before nesting attempts along with their migratory routes and destinations. This helps in refining and cleaning the area in order to regulate fishing and human activity, thus minimizing disturbance. Monitoring turtle population through nesting beaches and enhanced recruitment is an extremely practical and cost effective way to conserve the endangered sea turtle species. While a good amount of a turtles life is spent migrating and foraging, the nesting period during which these turtles come off shore to breed is the only time during which they can easily be accessible to researchers. The majority programs are comparatively successful in improving nesting success mired by human activity simply through presence and protection of nests[5]. Success is generally restricted by the collaboration of the community, since extra stress is placed on the people from communities apart from to the natural level of predation and mortality. In numerous developed countries the maintenance of nesting beaches with legislation and patrol programs linking community education have led to an increment in population growth rates. Even as there are more management problems in third-world nations, owing to insufficient of funding and lax legislation and enforcement, instilling a feeling of liability for the sea turtles in the local people can go a long way in incrà à µasing thà à µ nà à µsting succà à µss of thà à µ bà à µach.
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