The Return of the Salamanders
This year I managed to take video of the underwater breeding of spotted salamanders.
There are few more anticipated events in my naturalist year than the return of salamanders to their breeding ponds. Rain and warmth in the first half of April conspire to coax these exquisite creatures out of their woodland hiding places.
They walk purposely back to the ponds that cradled them in their larval stage, probably guided by odour, just as spawning salmon follow scent cues to return to their natal streams.
This year I managed to take video of the underwater breeding of spotted salamanders. Frenzied movement typifies these mating aggregations, which shouldn’t surprise. These salamanders have only a brief window of time to conduct the critical business of reproduction.
Most of the salamanders in the video are males, which can be distinguished from females by their enlarged cloacas, or vents, at the base of their tails. Males are also noticeably slimmer than females. The abdomens of gravid females are swollen with hundreds of eggs.
The small white mushroom-shaped blobs visible in the video are spermatophores deposited by the males. Females hover over these packets of sperm to fertilize their eggs.
The pond where the video was taken also hosts bizarre “piebald” spotted salamanders missing much of the usual pigmentation. Each piebald is uniquely patterned, allowing them to be easily recognized as individuals from year to year.
This led to a fascinating discovery this spring. I looked at the images of piebald salamanders taken by friends and myself in recent years and was astonished to find an individual that turned up in photos from 2010, 2011, 2017 and 2019. Assuming at least two years to attain adult size, this salamander is at least 11 years old!
I know that these piebald spotted salamanders, and their normally coloured brethren, will yield other surprises in the years to come. Spring of 2020 will once again find me pondside, with my flashlight – and my curiosity – burning brightly.