Comparison between the Hatching Success and Hatchling Fitness between In-situ and Hatchery Conservation Efforts in Sri Lanka
Sea turtle hatcheries are operated in a great deal in Sri Lanka. But their significance and contribution to population increase is doubted. Should the operation of such centers that lack scientific knowledge be allowed to continue, or should the turtle nests be left in their natural habitat. This study evaluated the best conservation practice (in situ or hatchery) employed in a developing country, Sri Lanka, for marine green turtles (Chelonia mydas).
The study was conducted from April to June- the peak season for green turtles nesting – at Kosgoda, Sri Lanka. By observing nesting and excavating nests, variables such as hatching success, clutch size, hatchlings’ flipper length and strength, carapace, plastron and speed were measured. These variables were compared using parametric and non-parametric tests. Correlation between carapace lengths, flipper lengths with respect to flipper strength was calculated.
The results showed that the hatching success in both methods was high at 93%-98% (In situ- 96.7% and hatchery- 92.6%). However, the hatchling fitness variables for hatchery hatchlings were found to be higher than that for in- situ in terms of carapace length, plastron length and flipper strength. However, there was no difference in the flipper lengths for the two methods. By calculating number of flips/time, the speed of the in situ hatchlings was found to be higher.
Hatchery hatchlings could survive after emergence due to physical strength but during their release, few hatchlings were predated by birds. Hatcheries do serve socio-economical purpose by providing local employment which helps the economy. But they don’t follow scientific protocols and allow tourists to handle turtles. In conclusion, hatchery methods should be employed only if in-situ conditions are unsuitable.