First report of the egg fertility of the hawksbill turtle (Eretmochelys imbricata) (Testudines: Cheloniidae) in Melaka, Malaysia

Abstract

The unhatched eggs of the hawksbill turtle (Eretmochelys imbricata) are often found in the hatchery in Melaka, Malaysia, raising concerns if the eggs remain unfertilized. Examining unhatched eggs during post-emergence nest excavation could lead to eggs being mistakenly identified as unfertilized eggs due to the difficulty in differentiating between unfertilized eggs and early embryonic mortality. It is essential to determine the egg fertility of hawksbill turtles in Melaka before concluding that hatching failure is due to infertility. Egg fertility was determined using the white spot method conducted at the beginning of egg incubation on 50 clutches. Mean egg fertility was 85.9%, but the mean hatching success was significantly lower at 57.6% (mean emergence success was 56.8%). The results showed that egg fertility did not reflect hatching success and infertility was unlikely the cause of hatching failure. The huge number of undeveloped eggs may have been due to early embryonic death that went undetected at the end of incubation.