Background:

The Crocodylia begin their life by overcoming the incubation stage with group hatching. Incubation temperature is important for the development of the embryos and the duration of the hatching process, during which they emit sounds.

Goals:

The effect of the size of the clutch on the duration and success of hatching is reported for the first time, and the hatching process is described.

Methods:

We used four clutches supplied by the “Granja de Lagartos” farm in Tabasco, Mexico, from the 2010 breeding season, and each was distributed in containers to integrate three clutches of different size: large (15 eggs), medium (nine eggs), and small (one egg). We monitored the temperature, relative humidity, and the number of eggs hatched in each clutch. The duration of hatching and the incubation period were statistically compared, as well as hatching success among the three brood sizes. We made sure that incubation conditions were the same for all boxes.

Results:

The small clutches (x̄ = 3340, ± 2794 min) and the medium-sized ones (x̄ = 1844 ± 476 min) took less minutes to hatch, and both took less time than the large clutches (x̄ = 9431 ± 768 min). The hatchings began with the vocalization of pre-hatching calls, heard up to a week before eclosion.

Conclusions:

The size of the clutch influences the duration of hatching, but is not related to hatching success.