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Management and conservation of the marine turtle in the state of Quintana Roo. A practical experience

Management and conservation of the marine turtle in the state of Quintana Roo. A practical experience

By Various Authors

Sea Turtles have lived on this planet for approximately 150 million years. Despite being protected, sea turtles need our help! They are regularly caught and slaughtered for their meat and eggs, and many are caught in fishing nets.


I.- Summary

This study evaluates the success of a management program for the species Chelonia mydas (white turtle) and Caretta caretta known as loggerhead, carried out by the civil association Flora, Fauna and Culture of Mexico, the study summarizes 10 years of work from 1999 to 2009, for this work we have the collaboration of the Nueva Vida de Ramiro project and the information summarizes 4 km of coastline known as Kanzul beach. There is data collected dating back to 1987, but we will only focus on the last 10 years. Through ¨in situ¨ monitoring, the number of species that come up to the beach to spawn, the number of nests, the number of eggs per species and the nests susceptible to being moved to safe places are determined, under the same conditions but away from natural predators and man. In the 10 years covered by the study, there have been 1,464 loggerhead nests (Caretta caretta) and 4184 white turtle nests (Chelonia mydas) on Kanzul beach, representing 11.19% and 12.96% respectively of the total nests registered in Along the 31.3 km of coastline covered by the program for both species, regarding the number of hatchlings released on Kanzul beach, we have that from 1999 to 2009 111,879 offspring of loggerhead (Caretta caretta) were released and for the same period 258,116 were released white turtle hatchlings (Chelonia mydas) on Kanzul beach, which represents 11.37% of the total loggerhead hatchlings released in 31.3 km of the Quintana Roo coast and 11.63% of the white turtle hatchlings.

II.- Introduction

Sea Turtles have lived on this planet for approximately 150 million years. These turtles migrate from as far away as South America.

In all parts of the world, sea turtles are considered threatened or endangered. Sea turtles are included in the CITES protection list, the IUCN red list, the Inter-American Convention list and the United States Endangered Species list. In addition, as a result of the large number of turtles caught in shrimp and other fishing nets, new laws have been established in Mexico and the United States requiring all trawlers to use TEDs (Sea Turtle Excluder Devices) that allow turtles to escape.

Despite being protected, sea turtles need our help! Turtles are regularly captured and slaughtered for their meat and eggs. Sea turtles mature very slowly and live long lives. They need to reach 20 or 30 years of age to sexually mature and reproduce. Also, many turtles return to the beaches where they hatched to lay their eggs.

The life cycle of sea turtles

Sea turtles are thought to be solitary in their early years, but as juveniles and adults they congregate at foraging (feeding), mating, and nesting sites. In general terms, turtles spend most of their life in the sea, although the females go out to the beach to lay their eggs periodically. Males may also emerge sporadically on the beach to regulate their temperature or avoid encounters with predators, although there is no absolute scientific certainty about these reasons.

All turtles reproduce through internal fertilization. After mating, the females migrate to nesting beaches, generally to the same beach where they were born. It is believed that they remember their home beach, having recorded in their memory during their journey from the nest to the sea chemical, physical and other factors not known until now.

When they are ready to lay their eggs, the females emerge on tropical, subtropical or temperate beaches, usually at night. With their fins they make a bed to accommodate their body in the sand. Then, with their rear fins, they excavate a chamber or hole, in which, depending on the species, they lay between 50 and 200 eggs per nest. Once they finish depositing them, they cover them with sand. A female usually does not nest in subsequent years; it will normally take two to four years to return, with the possible exception of olive ridley turtles.

Depending on the species, the young take between 45 and 75 days to be born. The sexes of the hatchlings are determined by the temperature of the sand during incubation - high temperatures produce females and low temperatures produce males. It is believed that of the hatchlings that emerge only one in 1,000 will survive to maturity. They leave their nests at dusk or dawn and head directly to the open sea, where they take refuge in ocean currents. Very little is known about this stage of his life, known as the "lost years." Sexual maturity takes between 10 to 50 years, depending on the species. There is no way to determine the age of a sea turtle by its physical appearance. Some species are believed to live for more than 100 years.

On the coasts of Quintana Roo, particularly in the area that concerns us for this study Kanzul Beach (4 km of coastline) in the Municipality of Tulúm, Quintana Roo, the species that frequently rise to nest are the Green Turtle (Chelonia mydas) and Loggerhead or loggerhead turtle (Caretta caretta) and with less frequency, rare appearances are the leatherback or leatherback turtle (Dermochelys coriacea) and Hawksbill turtle (Eretmochelys imbricata) this last species appeared on Kanzul beach only once in 10 years and 425 eggs were recorded. of which only 408 successfully hatched.

White Turtle, (Chelonia mydas)

Adults measure up to 1.5 meters in length and weigh more than 230 kg. It is the only herbivorous species among sea turtles and it feeds on sea grasses and algae. They are distributed in oceans and seas of all tropical regions of the world and, sporadically, in subtropical areas. At present there is a positive trend to growth in the population; however, the consumption of meat, fat and the illegal harvest of eggs in the Caribbean continues. It is estimated that at least 11,000 turtles are consumed per year (Chacón 2002). Currently, according to the Red List, it is in danger of extinction. The main nesting areas are in Mexico and the Galapagos Islands. The illegal harvest of eggs and meat remains one of its main threats. Their populations have been drastically reduced during the last 30 years (Chacón 2002).

Loggerhead or loggerhead turtle (Caretta caretta)

Adults are 90 to 110 cm long and weigh up to 180 kg. They are distinguished by their large head and jaws. Their diet is based on marine invertebrates (crabs and mussels, among others). It is distributed in temperate, tropical and subtropical zones of the Pacific, Indian and Atlantic Oceans and nests in various areas of the Mediterranean Sea. The loggerhead turtle prefers subtropical beaches for nesting and some of the main beaches are found on the East Coast of the United States and Mexico. Nesting on Central American beaches is rare. According to the Red List, it is in danger of extinction.

Leatherback or leatherback turtle (Dermochelys coriacea)

They are tortoises with shells without plates or scales; they have it covered by a thick layer of skin similar to leather. Today it is represented by only one species. It is the largest sea turtle in the world, which can measure up to 2.4 meters in length and weigh 500 kg or more. It feeds mainly on jellyfish. Its predominant color is black with some white spots. It is the sea turtle with the widest distribution: it is found in all temperate or tropical oceans and even reaches such cold waters of the sub-arctic. In the main nesting beaches, their populations have been reduced by up to 90% during the last decade (Chacón and Aráuz 2001). The extraction of eggs in nesting beaches and the mortality of adults caused by fisheries, are the main causes. Today, according to the Red List of Endangered Species of the World Conservation Union (IUCN), it is in critical danger of extinction.

Hawksbill Turtle (Eretmochelys imbricata)

Adult females are between 60 and 95 cm in length and weigh around 60 kg. Their carapace is made up of overlapping plates of dark brown or amber yellow brown. It is found on coral reefs and feeds on sponges, sea urchins and anemones. The design of the jaws, in the shape of a beak, allows it to reach the food located in crevices of rocks and corals. According to the Red List, it is in critical danger of extinction since it is captured for its shell, of beautiful color and high commercial value, used in the manufacture of jewelry, eyeglass frames, bracelets and spurs, among others. Tortuguitas and juveniles are also dissected to be sold as decoration and the penis of the males is attributed an aphrodisiac value. In addition, its meat, fat and eggs are consumed. It is the most tropical of the sea turtles and is distributed in the Caribbean and the Pacific.


I start of the Sea Turtle Conservation Program in Quintana Roo

Between 1982 and 1985, the first program for the protection and research of sea turtles was established on the central coast of Quintana Roo, by the Quintana Roo Research Center (CIQRO), it was they who described the enormous wealth of the State's coastline , as one of the largest areas in the world for the animation of Tortuga Blanca and Caguama, and they made the first diagnoses and protection activities in some of the beaches of the Litoral, within which is the Kanzul beach that goes from the Hotel Maya Tulúm until the Arch of Sian Kaan. In 1995, CIQRO disappeared, so Xcaret Park decided to rescue the program and continue with the protection and registration work carried out by CIQRO and in the same beaches until then.

In 2002, Xcaret placed the program in the hands of Flora, Fauna y Cultura de México A.C., with the aim of joining forces with other companies and organizations, in addition to Xcaret, thus ensuring financial sustainability and with it the continuity of the program. For its part, Flora, Fauna y Cultura de México A.C. I worked in the awareness program for the inhabitants of this coastal area and they were integrated into the Sea Turtle protection program, as collaborators, in the case of Kanzul beach, the project NUEVA was chosen as the center for the protection of nests and release of young VIDA de RAMIRO located at Km 8.5 of the Tulúm- Boca Paila Ruins highway.

III.- Development

Along the coast of the state of Quintana Roo there are 12 turtle camps that each cover between 1.5 and 5.5 km of coastline. They are part of the many collaborators of the Sea Turtle Conservation program in the state of Quintana Roo.

At Km 8.5 of the Tulúm - Ruinas - Boca Paila Highway is the Tortuguero camp that covers 4 km of coastline (Kanzul beach) within the NUEVA VIDA de RAMIRO property.

The Sea Turtle Protection Program includes several actions:

1.- Monitoring of the populations of White Turtles and Loggerheads, as the two species that historically arrive on the shores of Playa Kanzul.

To establish the nesting seasons of turtles each year, the date of the first and last clutch of each species is recorded, and a statistical analysis is carried out to see the variability by years and study the possible causes of the variations in time between one and the other. year.

2.- Transfer of the broods to the pens.

The work is extremely delicate and requires a lot of skill since the same natural conditions must be maintained for each nest and must be carried out within the first 6 hours from oviposition. The eggs of a clutch were moved to a protected site (corral) and were placed at a minimum separation of 0.80 cm, taking the edge of the neck of each one as the limit distance between nests, each clutch is marked with a stake where the data appear of the species, day and time of laying, number of eggs, and a record number, in a log, in addition to these data, the place where the eggs were deposited before being transferred to the corral is recorded.

What are relocated broods and clutches "in situ"?

The relocated clutches are so named because they are moved from the place where the mother left her to the corral, away from high tide or exposed to attack by natural predators and / or man; and the clutches ¨in situ¨, are those that are left in the place where they were deposited by the mother and that are not in danger, they are also monitored and recorded with all the data.

3.- Tours.

Kanzul Beach like the rest of the coast of Quintana Roo is an area of ​​high tourist demand, they are the most beautiful beaches in the Mexican Republic and in turtle animation season they are the months with the most visitors in this area of ​​the Mexican Caribbean so Day and night tours are organized as part of the turtle protection program.

The case of the Tortuguero camp on Kanzul beach is being worked on in coordination with the new eco-tourism project NUEVA VIDA de RAMIRO, as we have already mentioned, there the specialists of the A.C. Flora, Fauna and Culture of Mexico, those in charge of the program, receive all the logistical support, food, lodging, transportation, fuel and part of the property to install the pens to keep the nests in good condition and guarantee success in the incubation process. and hatching of the eggs.

The daytime tours are carried out every fifteen days when the animation season begins, the cycle of days can be shortened depending on the number of nests that appear, these are marked and all the data is taken and marked one meter away with stake.

The night tours are daily from 8:00 pm to 5:00 am the other day since it is the time with the most influx of turtles to the coast.

4.- Marking of females.

The females that go up to the beach to lay their eggs have steel marks applied to them that bear the legend "REPORT TO XCARET, PLAYA DEL CARMEN, QUINTANA ROO". The marks were placed on the rear edges of the front fins. In the case of the white turtle, a double tag is applied, due to the frequent loss of tags in this species. Even when the female goes up to the beach and for whatever reason does not leave her eggs, it is marked.

In case of finding marked females from other years, the registry of this already prepared is continued. All marked females are measured and their weights are calculated for monitoring.

IV.- Results

During these 10 years:

a) the registry of nesting and non-nesting turtles of the species Chelonia mydas (white turtle) and Caretta caretta (loggerhead), as those representative in this area of ​​the Mexican Caribbean,

b) counting and protecting eggs,

c) monitoring and release of young,

d) day and night tours to collect data and see the biotic and abiotic aspects that could affect the arrival of females to the coast,

IV.1.- Results of the clutches in 10 years (1999-2009) in Kanzul beach


1464 loggerhead turtle nests (11.19%) and 4184 white turtle nests were recorded for Kanzul beach (4 km of coastline) in the analyzed period, for 12.96% of the total nests registered for the same period on the coast of Quintana Roo from Aventuras DIF to Punta Yuyun, we are talking about 31.3 km of coastline.

IV.2.- Results of the number of hatchlings released, in 10 years (1999-2009) in Kanzul beach


For the Kanzul beach (4 km from the coast) in the analyzed period, 111,878 hatchlings released from the loggerhead turtle (11.37%) were recorded and 258,116 hatchlings released from the white turtle were recorded for 11.63% of the total nests registered for the same period on the coast Quintana Roo from Aventuras DIF to Punta Yuyun, we are talking about 31.3 km of coastline.

IV.3.- Results of the number of eggs in relation to the number of young born alive

Taking into account that the average number of eggs in both species is 120 eggs per nest, we have approximately 502,080 eggs of the Chelonia mydas species (white turtle) and 175,680 eggs of Caretta caretta (loggerhead), for the period 1999 -2009 at Kanzul beach

Loggerhead


White turtle


IV.4.- Mortality


In general, mortality in both species is very high year by year, but 2005 was significantly where the highest mortality was recorded in both species and this responds among other factors in that it was a year that they passed through this area of ​​the Mexican Caribbean. two of the biggest hurricanes recorded in recent years EMILY (July-2005) and WILMA (August-2005) just in the season of greatest hatching of the eggs.

Other factors that may be influencing egg mortality.

1.- natural predators,
2.- sudden variations in temperatures,
3.- bad disposition of the nests,
4.- bad handling of the eggs,
5.- little maturity of the embryos,
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Authors' Data:

  • Juan Antonio Acosta Giraldo - Doctor in Biological Sciences, director of GRUPO Consultor DISAM, SA de CV
  • Oscar Carreño Samso - Architect, Owner of the NUEVA VIDA de RAMIRO Ecotourism Project, base of the Kanzul beach turtle camp
  • Gea Ubilla Ortiz - Teacher, Owner of the NUEVA VIDA de RAMIRO Ecotourism Project, base of the Kanzul beach Tortuguero camp, director of the A.C. Origins of Quintana Roo.

Bibliography:

1.- Data provided by Flora, Fauna y Cultura de México A.C., technical report 2010,

2.- Chacón, D. and Aráuz, R. 2001. Regional Diagnosis and strategic planning for the conservation of Sea Turtles in Central America. Regional Network for the Conservation of Sea Turtles in Central America. 134p.

3.- Spotila, J.R., M.P. O'Connor, Paladino, F.V. 1997 Thermal Biology, in the biology of sea turtles, editions P.L. Lutz and J.A. Musick.

4.- Chacón, D., Valerín, N. and Cajiao Mª Virginia. Manual for best conservation practices for sea turtles in Central America. 139p.

5.- Chacón, D. 2002. Diagnosis on the trade of sea turtles and their derivatives in the Central American isthmus. Regional Network for the Conservation of Sea Turtles in Central America (RCA). San Jose Costa Rica. 247p.


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