Frequent rains have given members of the mole salamander
family many opportunities to migrate to their breeding pools. Most species head for quiet pools where they
lay a mass of eggs encased in a jelly-like envelope. The exception is the Streamside Salamander, a
species that utilizes intermittent headwater creeks as a depository for its
eggs.
Streamside Salamanders anchor their eggs to the underside of
flat rocks in the stream channel. Large,
well anchored rocks situated in moving water are ideal as a breeding site. A rock such as this can accommodate several
adult salamanders and allow them to perform courtship and egg laying activities
completely hidden from the eyes of any aquatic predators.
Occasionally, a female will select as a breeding site a
smaller rock that could be easily moved by fast moving water or a foraging
Raccoon. Eggs laid beneath a rock like
this are typically lost, so those inappropriate survival genes are eliminated
from the population.
This may not be a smart place to lay eggs, but it does give
me an opportunity to get some pictures.
I never move the large rocks. My
tampering could easily damage the eggs as well as destabilize the rock’s
position in the stream bed. Based on the
fact that the pools below the most promising large rocks fill with Streamside
Salamander larvae each spring, I think have a pretty good idea of what goes on
under those rocks.
Streamside Salamander eggs are laid individually. Water flowing beneath the rock keeps the eggs
clean and well oxygenated.
This salamander needs clean, rock bottomed creeks for
breeding. During most of the year, the
adults spend their lives below ground in the neighboring forest. Their appearance is almost identical to that
of the Smallmouth Salamander. I was told
by one expert that the only way to be sure of a specimen in hand was to do a
DNA analysis. I just assume that those I
find in the stream are Streamsides and those in the pond are probably
Smallmouths.
The eggs are just beginning to develop. The race is now on to make it through the
larva stage before the creek dries up for the summer.
Thanks for this post! I'm writing a post about Streamsides, since they live in this little urban forest.
ReplyDeleteHi, Rosemary. I'm glad this information is useful to you.
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