Earlier this summer a rare occurrence was discovered at CREW. A dusky pygmy rattlesnake gave birth to six offspring, three of which were amelanistic – meaning they lack the dark pigment (melanin) in their skin. According to Kevin Enge , a herp expert with the Florida Fish and Wildlife Commission, this is extremely rare and to have three of the six born amelanistic is quite amazing. No amelanistic pygmies have ever been documented before in Florida.
It is likely these three would not survive long in the wild because their rare coloration makes them easy to see and more vulnerable as prey. Below is a picture of the adult (with typical coloration) and one of the three amelanistic juveniles. Pretty cool, huh?
The location and the time of discovery were kept secret until after the young dispersed in order to prevent collectors from trying to find and collect them to sell. We assume that nature has taken its course, because after about five days the snakes had all moved on and haven’t been seen since early July.
Were these snakes born? Or hatched?
Karen- Good question. All rattlesnakes are ovoviviparous. That is, they produce a thin membrane around the embryo and these “eggs” are retained in the females body until “hatching”. The young may hatch while inside the female’s body or just after expulsion. (There is a good description of the three types of reproduction in snakes here: http://www.okrangelandswest.okstate.edu/files/wildlife%20pdfs/NREM-9010.pdf) Different sources use the words hatching or live birth – but the young are not enveloped in a placenta which provides nourishment like mammals. Look at the different descriptions from some online resources – “Females are viviparous (retain egg sacs internally), the young hatch and give the appearance of live birth.” – See more at: http://www.centralfloridazoo.org/duskypygmyrattlesnake#sthash.hf4r2rdN.dpuf or “Females are ovoviviparous – the young develop in eggs that the female retains inside her body. The young hatch from the eggs, then the mother gives birth to the live young. – Found at http://seaworld.org/animal-info/animal-bytes/reptiles/dusky-pygmy-rattlesnake/. So, it’s easy to get confused. Bottom line is – rattlesnakes are ovoviviparous. (that type of reproduction in between egg-laying and live birth)