REGRESSION MODEL ANALYSIS FOR DETERMINATION OF Amyda Cartilaginea MAXIMUM BREEDING AGE
DOI:
https://doi.org/10.59465/ijfr.2026.13.2.325-338Keywords:
Asiatic softshell turtle, captive, maximum breeding age, model, regressionAbstract
Harvest quota of Asiatic softshell turtle (Amyda cartilaginea) in Indonesia is the largest in the world. This has an impact on the decline in wildlife populations, given the lack of ex-situ conservation efforts and the fact that exporters prefer to take from nature. Information on the reproductive biology of the turtles is very important as a basis for conservation by estimating the speed of reproduction in order to maintain their population in nature. The purpose of this study was to determine the relationship between body weight and number of eggs on morphometric variations of the Asiatic softshell turtle (A. cartilaginea) as the basis for determining the maximum reproductive age. The method used is observational by measuring morphometric with Curved Carapace Length (CCL), Curved Carapace Width (CCW), Plastron Lenght (PL) and Plastron Width (PW) techniques. The results showed that the weight of the female ranged from 3 to 7.3 kg, CCL 20-48.4 cm, CCW 17.3-31.6 cm, PL 19.6-35.8 cm, and PW 17-34.5 cm. Weight (Y) is positively correlated with CCL (X) with the equation Y = 4.031X + 4.1885. The number of eggs (Y) can be estimated from Body Weight (X) with the allometric formula Y = 0.0117 X + 2.9424. These results indicate that the strongest correlation to the number of eggs is CCL. The age structure that produces the most eggs with good quality is from the adult age structure (CCL 35-40 cm) so that it can be recommended as a superior female for captivity.
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