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Journal of Life Sciences 6 (2012) 74-79 Nesting Activity and Conservation Status of the Hawksbill Turtle (Eretmochelys imbricata) in Persian Gulf Seyyed Mohammad Bagher Nabavi1, Ruhollah Zare2 and Mahdieh Eftekhar Vaghefi1 1. Department of Marine Biology, University of Marine Sciences and Technology, Khoramshahr, Khozestan, Iran 2. Department of Marine Biology, University of Chabahar Maritime and Marine Science, Chabahar, Iran Received: December 05, 2010 / Accepted: February 21, 2011 / Published: January 30, 2012. Abstract: Nesting activity, declining factors and conversation strategy of hawksbill turtle (Eretmochelys imbricata) in Persian Gulf islands investigated. Nesting analysis and hatchability has been monitored by counting. Our management strategy has been useful significantly in preserving hawksbill turtle existence. Depletion prevented, nesting habitats protected and better conservative programs designed. Key words: Hawksbill turtle (Eretmochelys imbricata), Persian Gulf, nesting season, conservation. 1. Introduction Globally, populations of sea turtles are declining and experiencing serious threats to their survival and are considered internationally as species of conservation concern. Over-hunting for their shells and meat, the collection of eggs from turtle nests, threatened by coastal development, pollution and pathogens, global warming and fisheries impacts, coastal development, pollution and pathogens, global warming and fisheries impacts are some factors attributing to the endangered status of turtles. Among these factors, fisheries impacts are thought to be one of the leading causes for sea turtle death and injury worldwide and can occur when turtles bite baited hooks, become entangled in fishing lines, are crushed by dredges, or otherwise held underwater by a variety of fishing methods (Figs. 1-7). Due to this status, they were listed in the World Conservation Union “Red List of Threatened Animals”; listed in the Appendix 1 of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). Fig. 1 Small turtle found in Sheedor Island. Fig. 2 Marine turtle in Hendooraabee for use in restaurants. Corresponding author: Ruhollah Zare, Ph.D., research field: marine biology. E-mail: [email protected]. Nesting Activity and Conservation Status of the Hawksbill Turtle (Eretmochelys imbricata) in Persian Gulf 75 Fig. 3 Hawksbill turtle captured in the net in Kish Island. Fig. 6 Different between normal and abnormal eggs. Fig. 4 Hawksbill turtle hatching in sand around bushes. Fig. 7 Shore erosion, a natural factor for eliminating nesting in Sheedor Island. use of powered boats in turtle hunting, commercial sale, habitat degradation, incidental by-catch in fishing gear, and the large scale harvesting of eggs in rookeries [2]. Fig. 5 Green turtle killed by a boat in Hormooz Island. The factors that are known to cause decline in sea turtle Nesting density of hawksbill turtles is low populations are generally similar but differences do throughout its range [1]. This means that all turtle exist in terms of importance for different populations species are considered endangered by international i.e., in different parts of the world, and with changing trade to such an extent that if commercial trade is not laws and technologies through time [3]. For example, eliminated with respect to these species, they will before the widespread use of trawlers and high seas become extinct. gill-nets, turtle mortality caused by fishing was It is believed that the declining turtle populations in minimal but laws were not in force to protect turtles the Persian Gulf has been accelerated by the and their products. Hence, there was widespread breakdown of traditional conservation practises, the hunting of turtles for meat, shell and leather. Eggs were 76 Nesting Activity and Conservation Status of the Hawksbill Turtle (Eretmochelys imbricata) in Persian Gulf affect any species. Natural predation on eggs and the nearest building, street, or other landmarks. These locations were later cross-referenced to the nearest survey marker. Nest and false crawl locations were recorded using Global Positioning System (GPS) receivers. The field survey also attempted to assess the suitability of the beaches for turtle nesting. The assessment only looked at the surface level of the beach area at high water mark (through which the turtle would crawl) and the nesting area (above high water mark). When there were many nests requiring relocation, additional trips were occasionally necessary. After recording all pertinent information, the crawl marks were obliterated to avoid duplication. Daily beach surveys commenced at sunrise or 6:00 a.m.. Surveys continued through May 25th. hatchlings is thought to be kept in check by natural 2.1 Time also collected extensively for food. Seas were not as polluted then, hence mortality caused by plastics, tar balls, pollutant induced diseases were not as extensive. Similarly, the degree of importance of factors threatening turtles in different parts of the world does differ. A constant cause for decline, independent of time, is when mortality is greater than recruitment. Mortality and recruitment vary, depending on predation, food availability and quality, habitat quality, and many other factors. Because the life cycle of a sea turtle is complex, and includes large periods of time and large expanses of the planet, mortality can occur at many places and many times during an individual turtle’s life. Natural threats are indiscriminate and may balances of predator prey relationships. Predation is so high that it is obvious that a number of terrestrial, marine and avian species depend on sea turtles as a source of protein (Loghmani, M). Anthropogenic threats (Table 1) to nesting habitats are again indiscriminate and driven more by coastal development, industrialization and the recreational opportunities provided by coastal environments. In addition to fulfilling statutory requirements, the purposes of the project were: (1) to relocate eggs from nests deposited in sites threatened by natural processes or human activities and thus maximize hatchling recruitment; (2) to survey sea turtle nesting patterns accurately to document historical trends and assess natural and anthropogenic factors affecting nesting patterns and densities; (3) to assess the success of sea turtle recruitment and of hatchery operations in terms of nesting success, hatching success and total hatchlings released; (4) to inform and educate the public about sea turtles and their conservation. 2. Materials and Methods Each nest location was initially recorded relative to The research was conducted from March through May 2007. This is the nesting season for hawksbill sea turtles in the region. 2.2 Study Area Qeshm is the biggest island in the Persian Gulf near the straits of Hormoz. Shidvar Island has an area of 8 sqkm, a coastline of 5.5 km. Hendourabi Island has a coastline of 20 km. Lavan Island is an Iranian Island in the Persian Gulf. It has an area of 76 km². Hormuz Island is an Iranian Island in the Persian Gulf. It is located in the Straits of Hormuz and is part of the Hormozgān Province. It has an area of 42 km2 (Fig. 1). 3. Results 3.1 Numbers of Nests The numbers represent the actual tally of records recorded during the surveys, some of which may not represent a good estimate for the month due to limited surveys conducted on some beaches during some months (Table 1). 77 Nesting Activity and Conservation Status of the Hawksbill Turtle (Eretmochelys imbricata) in Persian Gulf the only stretch used in the entire island by Hawksbill turtles for nesting and laying eggs. The coastline, therefore, represents an important and strategic Hawksbill hotspot. 2 km of the northern and eastern shores of Shidvar Island are suitable for the nesting of turtles. 2 km of Hendourabi Island is suitable for marine turtle nesting. Most parts are rocky shores, but there are some small a large sandy beaches suitable for nesting in east, north east and south Lavan Island has one of the four major terminals for export of crude oil in Iran and some of suitable nesting areas are under destruction. Fig. 8 Persian Gulf and the studied islands. 3.2 Threatening Factors During our investigation in different area of the studies region, variety of factors which considers as threat to sea turtle population was found. Table 2 has listed those factors. 4. Discussion In the past there has been a great deal of nesting of the hawksbill turtle at Persian Gulf but eggs collection and entanglement of adult females is rife. Shibderaz Village is in the centrally-located southern coastline of Qeshm Island which is currently Table 2 Table 1 Total hawksbill nests and nesting densities expressed as nest per kilometre. Island Beach length(km) Total nests Shidvar 36 2.1 Lavan 24 3.2 Qeshm 56 6.7 Hormuz 34 3.4 Farour 35 4.6 Hendurabi 46 5.7 231 25.7 Overall Current anthropogenic threat to sea turtle populations in Some Persian Gulf Islands. Threat Habitat alteration and loss Beach armouring (e.g., concrete sea walls) Beach nourishment/sand mining Beach cleaning and beach driving Human presence on beach Artificial light Boat strikes Animal predation at rookeries Oil pollution Other pollution sources and entanglement Fishing and incidental capture Shrimp trawling Pelagic fishing gear Gill nets Traditional and commercial fishing Egg harvests Adult harvests Shidvar Yes No No No Yes No Yes Yes ? Yes No No Yes No Yes Yes Yes Lavan Yes Yes Yes No Yes No Yes No Yes Yes Yes No Yes No Yes Yes Yes Qeshm Yes Yes Yes Yes Yes Yes Yes No Yes Yes Yes Yes Yes Yes Yes No No Hormuz No No No No Yes No Yes Yes ? Yes Yes No Yes No No No No Farour No No No No No No No Yes No No No No No No No No No Hendurabi No No No No Yes No Yes No No No No No No No No No Yes 78 Nesting Activity and Conservation Status of the Hawksbill Turtle (Eretmochelys imbricata) in Persian Gulf Main threatening factors of sea turtles in Persian Gulf are considered as: (1) In most parts of the nesting sites egg collection for traditional usage as well as aphrodisiac purposes is usual; (2) In some parts turtles harvest for their meat for the same purposes too; (3) Different kinds of pollutions are usual, like the debris, oil and light; (4) By catch in fishery activities is another important threat, as the turtle habitats are important fishing grounds too; (5) Natural predators like the other parts of the world are usual, like the mammals, birds, crabs and insects; (6) Density of the body pits in the small beaches prevent hatchlings to reach the sea; (7) Mismanagement causes problems in some parts; (8) Boat strike is usual and increasing in some parts; (9) Different kinds of coastal area development is another threat for the nesting sites and turtles; (10) Other natural factors like the erosion is usual in most places, specially in small beaches. 5. Conclusion Conservation measures and conservative programs that prevent sea turtles from being killed would be of priority. These two plans are as follow. 5.1 Conservation Measures These measures are needed to be planned to be practical and the objective are categorized as below: to reduce the incidental catch of adult and juvenile turtles in fishing gears, e.g.: (i) use of TEDs in trawlers (shrimp and fishing); (ii) regulate or ban the use of high seas gill-nets; (iii) regulations to protect turtles or restrict the use of fishing methods harmful to turtles off their nesting grounds during the nesting season. to curb the hunting and trade of live turtles, adults and juveniles, for meat and other turtle products. to reduce commercial exploitation of eggs, both legal and illegal. to prevent the destruction of nesting grounds by beachfront development, seawalls, land reclamation, etc.. to control the destruction of feeding grounds by trawlers, pollution, land reclamation, etc.. to avoid the killing or drowning of turtles in man-made structures (e.g., oil rigs) or by powered watercrafts. to restrain marine pollution to reduce the mortality of hatchlings, juveniles and adults caused by marine debris like plastic bags, tar balls, styrofoam, etc.. to prevent the inducement and spread of diseases that may be anthropogenically related, e.g. fibriopapillomas. 5.2 Conservative Programs The conservation programs are described as below: nomination of sea turtles as “endangered animals” of the country; there was a fine of about 3,200,000 Rials for each killed turtle which doubled in the past year (6,400,000 Rials), about US$700; and also fine for egg collection, about $US 233 for each; nominating of the nesting sites as “under management and control area” like Mond protected area and shidvar wildlife refuge; monitoring of the sites by DOE guards. In order to respond to a critical conservation situation, as is the case of these sea turtle populations, an agreement must fulfill some requirements: (1) it must include all, or most of the countries involved in the problem. (2) it must be an “agile” organization, capable of facing a dynamic situation without getting bogged down with time consuming formalities. (3) it must turn words into actions very rapidly; and perhaps also. (4) it must have the capability to implement and execute a comprehensive program. Nesting Activity and Conservation Status of the Hawksbill Turtle (Eretmochelys imbricata) in Persian Gulf (5) if possible, it is preferable that the agreement is a binding one. It is quite clear that the institution must have a level of credibility with the different stakeholders. Acknowledgment The authors express their appreciation to Department of Environment of Hormozgan province for their serious and great cooperation in this research. 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