Thursday, May 11, 2017

In a knot...

Yesterday, as I was collecting some pond water at Chipp-A-Waters Park, I noticed four different Northern Water Snakes (Nerodia sipedon) around the margins of the ponds.  I have found snakes around this pond before; the pond is full of things they like to eat such as frogs, tadpoles, fish, leaches, etc..  So it was no surprise to find one near this pond.  It was unusual to find more than one at a time.

It's confusing, but you can count four snakes in this picture - the female is the biggest and the other three are males

Why were all of these snakes congregated in one place?

The answer to that question soon became obvious.

One of the snakes that I saw was significantly larger than the other three snakes.  Not only that, but the three smaller snakes were vigorously pursuing the largest snake.  Eventually all four snakes clustered together in a loose ball on some cattail stalks a dozen feet from the edge of the pond.

The period April to June is mating season for Northern Water Snakes.  The largest snake was a female.  The smaller snakes were males, competing for the opportunity to mate.  Eventually one (or more) of the males successfully mated with the female.

Female (center) and largest male (right) Northern Water Snake - he was the apparent winner of the mating competition.

I don't expect to find a bunch of snake eggs any time soon.  Northern Water Snakes give birth to live babies (7 to 9 inches long) during late summer.  Once the babies are born they are completely on their own.

One thing that I noticed about these snakes was the color variation.  All Northern Water Snakes have a pattern of dark striped with a (usually) lighter background of brown or grey.  As they age, their colors typically darken so there is little difference between the stripes and the background color.  On of the three male snakes was noticeably lighter than his co-suitors.  His stripes were an almost olive green against a tan background.  You can this in the two pictures below.

A lighter color morph Northern Water Snake

In this photo you can really see the color variation in the species - fours snakes, four different colors

It's nice to have the opportunity to see and interact with this species.  I didn't see my first Northern Water Snake in the wild in Mt. Pleasant until 2013, despite having worked in Mt. Pleasant Parks for nearly a decade.  Now I see them on a somewhat regular basis, especially at Chipp-A-Waters Park.

Just for fun...  A group of snakes can be known as a"knot".  I can see why!

No comments:

Post a Comment