Abstract
Coconut crab (Birgus latro) is a crustacean that has a large size until four kilograms. The study aimed to analyze sex ratio and growth pattern including the relationship of thorax length - body weight, thorax width - body weight and cephalothorax length plus rostrum - body weight in Daeo (Morotai Island), Laigoma (South Halmahera District) and Fitako (North Halmahera District). The sex ratio was determined using χ2 test and the growth pattern was tested by the b value through t test. The results showed sex ratio of 1: 0.9 in Daeo (n = 581), 1: 0.6 in Laigoma (n = 24), and 1: 2 in Fitako (n = 31). The relationship of thorax length, thorax width and cephalothorax length plus rostrum with body weight were strongly correlated (R2> 70%). The growth pattern of coconut crab in Daeo was negative allometric, while in Laigoma and Fitako were negative allometric and isometric.
Highlights
Robber crab or coconut crab (Birgus latro) is a crustacean group of the Coenobitidae family found primarily in tropical regions of the Indo Pacific (Drew et al, 2010) and in sub-tropical of Japan (Hamasaki et al, 2011; Sato et al, 2013)
This study aimed to analyze the sex ratio and growth pattern included the relationship of thorax lengthbody weight, thorax width-body weight and cephalothorax length plus rostrum-body weight in Daeo District Morotai Island, Laigoma District of South Halmahera and Faitako District of North Halmahera Indonesia
The coconut crab samples during this study were 636 individuals consisting of 581 individuals collected in Daeo (54% male and 46% female), 24 individuals collected in Laigoma (62.50% male and 37.50% female) and 31 individuals in Fitako (29.03% male and 70.97% female)
Summary
Robber crab or coconut crab (Birgus latro) is a crustacean group of the Coenobitidae family found primarily in tropical regions of the Indo Pacific (Drew et al, 2010) and in sub-tropical of Japan (Hamasaki et al, 2011; Sato et al, 2013). This species is found in three island groups at Indian Ocean, there are Aldabra Atoll, Chagos Islands and Nicobar, and Andaman Islands. Other names are “butati” in Fitako and surrounding areas (North Halmahera Regency) and “gafan” in Laigoma region (South Halmahera Regency)
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call