Friday, March 14, 2014

Streamside Salamander

While looking beneath some decomposing wood in the stream channel, I was lucky enough to find an adult Streamside Salamander.  This is the first adult of the species I’ve seen at the creek for almost ten years.  I always enjoy finding salamanders.  It’s a double treat when the species I discover is a rarity.


I always check around this time of year to monitor the breeding success of the Streamside Salamanders.  This particular species attaches its eggs to the underside of submerged flat rocks in moving water.  Fortunately, the creek has an abundance of flat rocks.  This particular rock protected a clutch of eggs two years ago.  Since then it has moved with the flood water about 20 feet downstream.


Rocks that move during high water flows do not provide the safest situation for developing salamander eggs.  If a flood begins to scoot this rock along, the eggs will most likely be lost.  The fact that I’ve again found eggs here must indicate that there is something about this rock that beckons the breeding salamander.


Large rocks that maintain their position from year-to-year provide the best egg laying locations.  The pool below these flat rocks fills with salamander larvae each year.  These rocks are large enough to accommodate multiple females.


This droopy head posture makes it appear that the salamander doesn’t have the neck muscles to hold its head up.  Its natural tendency when placed in the open is to burrow or get beneath something.  The rock offers no ingress, but if a crack or hole were encountered, the head would go in and the body would quickly follow.


The Streamside Salamander has a base color and markings that closely match the rocks in the creek.  This species spends most of its life in underground burrows and comes to the surface only at breeding time.  Most of the breeding time is spent in the creek, so being able to match the substrate in that location is a valuable asset.


The vertical grooves along the side of the body are called costal grooves and each represents the position of a rib.  The number of costal grooves is sometimes used to distinguish species, such as the Streamside and the nearly identical Smallmouth Salamander.  Unfortunately, that’s not a guaranteed method of identification, so I’m just relying on the fact that this guy was in a stream and am calling it a Streamside.


This individual had a particularly chunky tail.  The tail is used as a fat storage area, so a big tail indicates a healthy salamander that is feeding well and has an excellent chance to survive the lean times.  This tail was so large that it made the animal appear out of proportion.  I hope the rest of the population is doing as well.

3 comments:

  1. Hi Katie. Salamanders are always cool. I've enjoyed your posts about salamander and newt finds in California.

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  2. I'm still ogling that tail. I've also seen some rather healthy newts and frogs recently. I'm amazed at how fat they can get.

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