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Marine Turtle Newsletter 103:13, © 2004

Marine Turtle Newsletter-Online

Nesting of the Hawksbill Turtle at Shidvar Island, Hormozgan Province, Iran

Asghar Mobaraki
Department of Environment, P.O. Box 5181-15875, Tehran-Iran (E-mail: amobaraki@hotmail.com)

Shidvar Island of the Islamic Republic of Iran, with an area of 80ha (26°48`N, 53°25`E) is located in Hormozgan province, in the Persian Gulf. It has a coast line of 5.5km of which 2km are sandy beaches suitable for marine turtle nesting. This island has been reported as one of the most important nesting sites for hawksbill turtles (Eretmochelys imbricata) in Iran. For this reason, as well as its importance as a nesting site of bird species (lesser crested tern Sterba bengalensis, crested tern Sterna bergii, bridled tern Sterna anaethetus) it has received nomination as a protected area, including RAMSAR status.

Although this island has profound importance, regular studies have not been undertaken. To gain an insight to the biology of hawksbill turtles nesting at the site the island was visited for 1 week from 6-11 May 2003. This was thought to be good timing for a short trip as nesting in the region is thought to be largely between March and June. During our stay, 30 female hawksbill turtles emerged for nesting but only seven of them successfully laid a clutch of eggs. No other nesting marine turtle species were identified. Morphometric data on nesting females and eggs were gathered and thirteen of these individuals were tagged using metal flipper tags. Of 23 females measured, mean (±SD, range) curved carapace length was 71.0 cm (±3.1, 64-75cm), mean curved carapace width was 65.6cm (±2.5, 60-71cm) and mean body weight was 37.7kg (±4.1, 30-45kg). The seven clutches examined had an average of 98.4 eggs per clutch (±15.8, 79-118 eggs) with mean of mean egg weights 27.8g (±2.0, 25.7-31.6g) and a mean of mean egg diameter of 37.0mm (±1.0, 36.2-38.9mm).

These limited data confirm that Shidvar Island is of tremendous biodiversity importance. This is enhanced by the fact that it is not subject to human habitation and is free from other mammalian predators. The likelihood that successful conservation of this island can play a positive role in safeguarding regional hawksbill populations is high. It is hoped that more extensive studies will be possible in the future to allow a more detailed population assessment and insights into the biology of the hawksbill turtle in this region.