Nesting Ecology and Postnesting Migration of Sea Turtles on Taipin
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NOTES AND FIELD REPORTS 277 Programas de Conservacio´n de Tortugas Marinas, Penı´nsula ROSS, J.P., BEAVERS, S., MUNDELL, D., AND AIRTH-KINDREE,M. de Yucata´n. Universidad Auto´noma de Yucata´n, pp. 77–90. 1989. The status of Kemp’s Ridley. Center for Marine GUZMA´ N-H., V. 1996. Resen˜a de la temporada de anidacio´n en Conservation. Washington, DC, 51 pp. Campeche, Me´xico, durante 1996. Doc. Te´c. del Centro Reg. US-MEXICO PROGRAM. 2004. Report on the Mexico/United States de Invest. Pesquera de Cd. del Carmen. No 3. Unpublished of America population restoration project for the Kemp’s report to Programa Nacional de Tortugas Marinas, INP, 9 pp. Ridley turtle, Lepidochelys kempii, on the coast of Tamaulipas GUZMA´ N, V. 1997. Informe te´cnico del Programa de Investigacio´n and Veracruz, Me´xico, 2004. US Fish & Wildlife Service- y Proteccio´n de Tortugas Marinas en Isla Aguada, Campeche. Gladys Porter Zoo-SEMARNAT-SEDUE, 13 pp. Temporada 1997. Doc. Te´c. del Centro Reg. de Invest. ZUG, G.R., KALB, H., AND LUZAR, S.J. 1997. Age and growth in Pesquera de Cd. del Carmen. No 5. Unpublished report to wild Kemp’s Ridley sea turtles Lepidochelys kempi from Programa Nacional de Tortugas Marinas, INP, 8 pp. skeletochronological data. Biological Conservation. 80: GUZMA´ N, V. 2000. Evaluacio´n de las poblaciones de tortugas 261–268. marinas de Campeche. Avance y Perspectivas. Informe Received: 4 January 2005 Te´cnico de Investigacio´n 2000/11/ SEMARNAP/INP/ Revised and Accepted: 23 June 2006 DGIPDS/CRIP Carmen. Unpublished report to Instituto Nacional de la Pesca, 23 pp. GUZMA´ N, V. 2001. Evaluacio´n de las poblaciones de tortugas marinas de Campeche. Sinopsis de la proteccio´n e inves- Chelonian Conservation and Biology, 2007, 6(2): 277–282 tigacio´n 1977–2001, con reporte de investigacio´n 2001/INE/ Ó 2007 Chelonian Research Foundation DGVS/TM-007-Camp. Informe Te´cnico de Investigacio´n 2001/12/ SAGARPA/INP/DGIPDS/ PNTM/CRIP Carmen, Unpublished report to Instituto Nacional de la Pesca, 37 pp. Nesting Ecology and Postnesting Migration GUZMA´ N, V. 2002. Resen˜a de la temporada de anidacio´n de of Sea Turtles on Taipin Tao, tortugas marinas en Campeche, Me´xico; durante el 2002. Con Nansha Archipelago, South China Sea reporte del campamento tortuguero de Isla Aguada en 2002. INE/DGVS/TM-007-Camp. DGVS/SEMARNAT/Delegacio´n 1 Federal en Campeche. Unpublished report to Programa I-JIUNN CHENG Nacional de Tortugas Marinas, 19 pp. GUZMA´ N, V. 2004. Temporada de anidacio´n 2003 de tortugas 1Institute of Marine Biology, National Taiwan Ocean University, marinas en Isla Aguada, Campeche, Me´xico; y panorama Keelung, Taiwan, 202-24, Republic of China estatal. INE/DGVS/TM-007-Camp. SEMARNAT/DGVS/ [[email protected]] Delegacio´n Federal en Campeche. Unpublished report to Programa Nacional de Tortugas Marinas, 24 pp. ABSTRACT. – The South China Sea is one of the most GUZMA´ N, V., REJO´ N, P.J.C, GO´ MEZ, G.R., AND SILVA, J. 1994. important areas for sea turtles in China. Taipin Tao is Informe final del programa de investigacio´n y proteccio´n de las tortugas marinas del estado de Campeche, Me´xico., the largest island in the Nansha Archipelago and is a Temporada 1993. Panorama regional. Unpublished report to nesting site for green and, possibly hawksbill, turtles. INP-CRIP Carmen, 49 pp. Satellite telemetry studies from the year 2000 till 2003 GUZMA´ N, V., REJO´ N, P.J.C., GO´ MEZ, G.R., AND SILVA, J. 1995. demonstrated that the green turtles nesting at Taipin Informe final del programa de investigacio´n y proteccio´n de Tao are a shared natural resource among the nations las tortugas marinas del estado de Campeche, Me´xico. in the southern South China Sea. Regional and Temporada 1994. Situacio´n actual. Unpublished report to international cooperation overseen by international CRIP Carmen I.N.P.-SEPESCA. Bol. Te´c. No 1/95, 32 pp. GUZMA´ N, V., SA´ NCHEZ-P., J.M., GO´ MEZ, G.R., REJO´ N, P.J.C., AND organizations is desperately needed for the effective SILVA, J. 1993. Informe final del programa tortugas marinas de protection of the green turtles nesting at Taipin Tao. Isla Aguada Carmen, Campeche. Temporada 1992. Una perspectiva regional. Unpublished report to INP-CRIP-Car- men, 82 pp. The South China Sea is host to more than 90% of the HILDEBRAND, H. 1981. A Historical review of the status of sea sea turtle populations in China (Liang et al. 1990). An turtle populations in the Western Gulf of Mexico. In: Bjorndal, understanding of the nesting environment and status of the K. (Ed.). Biology and Conservation of Sea Turtles. Wash- nesting population is crucial to the conservation and ington, DC: Smithsonian Institution Press, pp. 447–453. management of sea turtles in the region. However, political ´ MARQUEZ-M., R. 1978. Natural reserves for the conservation of instability in the South China Sea, especially the Spratly marine turtle of Mexico. Proc. Fla. Interreg. Conf. on Sea Turtles, July 24:25. Fla. Mar. Pub., 33: 56 p. (Nansha) Archipelagos, complicates the surveys and MA´ RQUEZ-M., R. 1994. Sinopsis de datos biolo´gicos sobre la conservation measures of the sea turtle (Cheng 2000a). tortuga Lora, Lepidochelys kempi (Garman, 1880). FAO The military presence on most islands further prevents Sinopsis sobre la Pesca, No. 152. INP/S152, SAST-Tortuga surveys of the sea turtles, both on the beaches and in the Lora 5.31(07)016.02. Me´xico, 104 pp. sea. Thus, little is known about their present status. MA´ RQUEZ-M., R. 1996. Las tortugas marinas y nuestro tiempo. Taipin Tao has been occupied by the Marines from Fondo de Cultura Econo´mica/ Secretarı´a de Educacio´n Pu´blica/ the Republic of China for more than 50 years. Surprisingly Consejo Nacional de Ciencia y Tecnologı´a. Me´xico DF, 197 pp. PRITCHARD, P.C.H. AND MA´ RQUEZ, M. 1973. Kemp’s Ridley or the little was known about the ecology of this island and the Atlantic Ridley,Lepidochelys kempi. IUCN Monographs, nearshore waters. In 1994, a 5-day comprehensive Marine Turtle Series, 230 pp. ecological survey was carried out to investigate the coral 278 CHELONIAN CONSERVATION AND BIOLOGY, Volume 6, Number 2 — 2007 Figure 1. The map of Taipin Tao, Nansha Archipelago, and the spatial distribution of the emergences on different sections of the beaches on the island from both 1995 interviews and 2000–2002 field records. The fringe outskirts are coral reefs. Letters denote the beach section where the survey was carried out. reefs, fishes, macrobenthos, macroalgae, planktons, ceta- ranges from 24.28Cto328C, with a yearly average of ceans, water quality, terrestrial plants, and birds of this 28.18C. The yearly total precipitation is more than 1800 island (Fang and Li 1994). However, nothing is known mm (Naval Weather Center 1996, and this study). about the sea turtles, except for a few underwater The researchers were allowed to remain on the island photographs. Information from the navy, as well as from for 5 days in 1995 (Cheng 2000a) and for 36 hours on each soldiers residing on the island strongly suggested that this of the consecutive trips. Because of these limitations, the island may host a large nesting population. With the nesting ecology of sea turtles on the island was surveyed support of the Defense Department and the Council of mainly by means of questionnaire interviews of the Agriculture, Republic of China (R.O.C.), a preliminary soldiers on the island in 1995 and by daily records of survey was carried out in 1995 (Cheng 1996, 2000a), the patrol team, which walked the beaches around the follow-up surveys were carried out from 2000 to 2003 to island once every 3 hours from 1900 to 0500 hours and study the nesting population and conduct research by from the guards on the watch posts by the beaches each using satellite transmitters on the postnesting sea turtles to night (2000 to 2002). The beach was divided into 9 determine their migration corridors. The purpose of this sections, based on the location of the watch posts where study was to provide updated information on the nesting the patrollers started their field surveys every night (Fig. ecology of sea turtles on Taipin Tao and on potential 1). The records include the date, species, site, emergence foraging sites of green turtles that nest on the island. phase (crawling, digging, nesting, or descending), size Recommendations for conservation measures are pro- (curved carapace length; CCL), health status, and fate of vided. these turtles. Methods. — The Nansha Archipelago (Spratly To determine the sex ratio of the hatchlings on the Islands) is composed of 102 coralline island, atolls, and island, 3 temperature loggers (Onset Optic StowAway shoals. Taipin Tao (108220N, 1148220E) is located near the Logger) were buried in the nesting beaches around the middle of the northern archipelago, which was 1365 m island at a depth of ;70 cm in April 2002. The loggers long and 360 m wide, with an area of 0.48 km2. The island were set to record sand temperatures every 1 hour 12 is forested with lowland tropical rainforest and reaches an minutes. Thus, 22 sand temperature records were recorded average topographic height of 3.8 m (Fang and Li 1994). each day, with a total of 7428 measurements over 372 The sand particles are mainly shell debris and fine coral days. Daily air temperature and precipitation were fragments. Coral reefs fringe the island and extend obtained from the Naval Weather Forecast Center, Taiwan, 100À200 m offshore.