20 November 2012
In the winter months (June to August) a lot of reptiles cool down prior to breeding (the cooler temperatures can often help improve their fertility) and then by spring (September to November) depending on the weather, most species are actively breeding (for example, female Crocs will scratch up their nests and wait for a stormy cycle before laying eggs).
Across the reptile world there are many different methods of producing young - some animals dig nests in the ground, some scratch up mulch nests, some lay individual eggs, some lay large clutches, others are live bearers with 1 or 2 young or even up to 25 in a litter! All of these different techniques can improve the chances of survival for the next generation.
Most egg laying reptiles will lay early in spring, so they have time to incubate and then give the hatchling time to have a few feeds before the next winter sets in, whereas live bearers can carry the young for a bit longer as they don't have to worry about incubation time.
Reptiles vary as far as maternal instinct goes, with most live born animals left to fend for themselves from day one. Most species of lizard are on their own from the start too, with a few occasional exceptions, but with snakes it varies (eg. most pythons will usually coil around the eggs incubating them themselves, using a series of muscular twitches when necessary to heat the eggs), however once the eggs hatch they are on their own. Some species of venomous snakes in Australia will even lay their eggs and then leave them to hatch on their own and fend for themselves. Then there is the saltwater crocodile - now there is a good mother! These guys will defend the nest, and even the young for a couple of months after hatching, sometimes literally with their lives. Crikey!
Here at Australia Zoo it is always an exciting time of the year for Reptile Keepers, waiting to see which animals will breed and reproduce. We have a number of animal species that we try to breed annually, including the endangered Brigalow Woma Python. So, the next time you're walking around the Zoo during breeding season be sure to check out our nesting crocs or the million and one baby water dragons running around for all to see around New Year, and don't forget, Reptiles Rule!