Having been involved in urban wildlife management for close to a decade now, I have been on the receiving end of many cobra eggs. Varying circumstances cause these ‘orphaned clutches’ to land up in my care, either the eggs are forcefully abandoned by rescue of the mother or are clutches from captive cobras in Bannerghatta Zoo handed over to an expert by the Forest Department. Most often, however, they are found by accident while excavating on construction sites.
Naja Naja, or the spectacled cobra, is oviparous (producing young by means of eggs) and lay their clutches in rat holes or termite mounds in the hot pre-monsoon months (April to July). One clutch comprises of anywhere between 10 to 30 eggs of which hatchlings emerge roughly 48 to 68 days later. What has always amazed me is how each hatchling is independent upon birth, with fully functional venom glands that they learn to use by powerful natural instinct.
I have been exposed, on multiple occasions, to the delicate process of captive breeding and egg incubation (of cobras and other reptiles). From these experiences, I observed and learnt about the varying factors that need to be regulated so as to be able to achieve full success in hatching.
Typically, incubation is performed under the accuracy (and assurance) of sophisticated incubators that one uses to design a highly controlled environment for the purpose. Apart from being hard to access, this kind of scientific equipment is not cheap either so I hadn’t the luxury of using an incubator.
Instead, I was handed each clutch in a plain cardboard box, leaving me to conceptualise my own apparatus for incubating these clutches of cobra eggs. What I constructed was a simple set up that consisted of a thermometer, plastic container, hydrometer, vermiculite and charcoal. All my equipment was well researched, peer-reviewed and.. made at home!
Cobra eggs take 70 to 100 days to hatch in an incubator. In this expertly controlled environment, temperature and humidity need to be raised in accordance to one another so as to offer suitable conditions for hatching. As one can imagine, achieving this on a homemade, DIY system threw up new challenges every day, demanding constant improvisation based on my assessment of new developments.
In the process, I shifted the box frequently between rooms to offer variations in ambient conditions, using my discretion and judgement of what works best. Quite often the box of eggs would up in my bathroom where levels of moisture happened to be at its best. On that front, regulating humidity turned out to be the biggest obstacle; trial, error and constant dialogue with experts pushed me to choose a little known but time-tested method to tackle the issue of humidity.
I made a couple of holes in the box, stuffing them lightly with cotton to keep moisture from escaping. I had to repeat the exercise multiple times a day and on a timely basis. I would keep select holes closed during specific time slots in the day, regularly switching the swabs of cotton around strategically, eventually achieving ideal humidity for incubation.
Yet another amusing aspect that added it’s own element of uncertainty to the process was that I never actually knew the age of a clutch given to me. Everyday held the possibility of watching baby cobras wiggle out of the safety of their shells. It surely was an exciting time to be me!
I am happy to report 100% success rate for all the clutches I tended to, a total of 400 baby cobras that I have incubated and released into the wild.