Effect of nest flooding in the hatching success of Caiman latirostris eggs

CEDILLO-LEAL, C.; SIMONCINI, M.; LEIVA, P.; LARRIERA, A.; PIÑA, C.I.

Skukuza

Congreso; 24th working meeting of the Crodoile Specialist Group; 2016

CSG/SSC/IUCN

Floods are one of the main causes of loss of wild nests in crocodilians, however there is little information about embryos tolerance to be submerge, and the role that eggshells structures have against flooding. The objective of this research was to determine the effect of flooding on hatching success of Caiman latirostris eggs flooded at two stages of embryonic development and whether the eggshells structures (or roughness) influences the tolerance of embryos to flooding. We used 10 nests, separated into two groups of five nests; eggs of each nest were divided into four treatments with nine eggs each (1. Control of flooding; 2. control of eggshell structures; 3. Flooded; 4. Flooded without eggshell structures). The five nests of one group were flooded when each nest reached day 30 of incubation period, nests of the other group were flooded when they reached day 60 (in both situations nests were flooded for a period of 10 hours). After 30 days of incubation flooding did not affect hatching success, but it was reduced in flooded eggs without eggshell structures. After 60 days of incubation period, flooding decrease hatching success in both groups (with or without eggshell structures). We concluded that hatching success is affected by timing of flooding; and if flooding occurs during the 30 days of incubation, clutches with eggshell structures increase the tolerance of eggs.