Assessing Nesting Status of Green Turtles, Chelonia Mydas in Perak, Malaysia
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Abstract
The nesting of green turtle (Chelonia mydas) was monitored from 1998 untill 2013 along the beaches of Pasir Panjang, Segari, Perak. The objective of the study is to assess the nesting status of green turtles in Perak, Peninsular Malaysia in terms of total nests, eggs, survival hatchings, and density of visitors. A total number of green turtle nests found for 16 years were 1,019 nests and varied from 10 to 220 nests per year. Meanwhile, the sum of eggs collected for 16 years were 107,820 eggs, and varied from 553 to 20,881 eggs per year. The temporal pattern of nesting indicates year-round nesting in Perak in most years within the 16 years period. The peak season of nesting was estimated to occur between May and June. Survival hatchlings varied from 23.33% (2,071 hatchlings) to 55.03% (5,018 hatchlings) from 1998 to 2013. The density of visitors was not uniformly distributed among the years, and shows a sign of decline especially from 2006 onwards. This publication provides basic knowledge of green turtle nesting population in Perak, and would be helpful in upgrading the conservation program in Malaysia. In future, we hope 1) for an increase in manpower to obtain accurate nesting records along the nesting beaches during nocturnal survey and, 2) to include the breeding biology data such as nest placement, emergence hour, and morphological characteristics of green turtle.
Sarang penyu agar (Chelonia mydas) di pantau dari tahun 1998 hingga 2013 di sepanjang pantai Pasir Panjang, Segari, Perak. Objektif kajian ini ada untuk melihat status bersarang penyu agar di Perak, Semenanjung Malaysia dari sudut kajian jumlah sarang, telur, survival anak penyu, dan kepadatan pelawat. Jumlah sarang penyu agar yang dijumpai dalam tempoh 16 tahun adalah sebanyak 1,019 sarang, dan berbeza dari 10 hingga 220 sarang setiap tahun. Sementara itu, jumlah telur yang dikutip dalam tempoh 16 tahun adalah sebanyak 107,820 telur, dan berbeza dari 553 hingga 20,881 telur setiap tahun. Corak temporal menunjukkan Perak mempunyai taburan sarang di sepanjang tahun di kebanyakan tahun dalam tempoh 16 tahun. Musim kemuncak waktu bersarang dijangkakan berlaku di antara Mei dan Jun. Survival anak penyu berbeza dari 23.33% (2,071 anak penyu) hingga 55.03% (5,018 anak penyu) dari tahun 1998 hingga 2013. Kepadatan pelawat adalah tidak seragam antara tahun, dan menunjukkan penurunan terutamanya dari tahun 2006 dan ke atas. Penerbitan ini mengetengahkan ilmu asas berkaitan populasi sarang penyu agar di Perak, dan mungkin berguna ke arah meningkatkan program pemuliharaan di Malaysia. Di masa hadapan, kami mengharapkan 1) peningkatan jumlah tenaga pekerja semasa tinjauan di waktu malam di sepanjang pantai bersarang untuk ketepatan rekod catatan, dan 2) mengetengahkan maklumat biologi pembiakan seperti lokasi penempatan sarang, masa pendaratan, dan ciri-ciri morfologi penyu agar.
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