Water depth, glare, and wind ripples have made it impossible
for me to see whether or not the sunken tiles, rocks and boards, intended to
receive the eggs of the Streamside Salamander, have actually been used this season.
Streamside Salamanders typically lay their eggs on the undersides of flat rocks
in small flowing streams. Absence of flowing water and large flat rocks will
not necessarily make these salamanders abandon their breeding efforts. I added
a breeding structure to the pond at Blue Jay Barrens in an attempt to provide a
population of pond breeding Streamside Salamanders with a suitable structure to
receive their eggs. In the past, this breeding aid has been readily used, but
even in its absence Streamside Salamanders find a way to anchor their eggs and
ensure breeding success.
When the water level drops in early summer, I use this board
as a way to cross the mud between the dry bank and open water. During the
winter and early spring months, I allow the board to float freely in the pond.
I used to remove the board during the winter and put it in a
dry location for storage. One year the pond filled quickly from a late autumn
rainstorm followed by a quick freeze that trapped the board in the ice in the
center the pond. The board stayed out of reach until early spring. When I
finally went to pull it in, I found the bottom surface covered with Streamside
Salamander eggs. Now I just let the board stay in the pond as an alternate
breeding site for the Streamside Salamanders.
The Streamside Salamanders also utilize as an egg laying
site, pads of terrestrial moss that grow on the bottom of pond during the dry
season. The activity of the egg laying salamanders causes the moss to lose
contact with the muddy pond bottom and begin to float free.
Some of the moss pads containing egg clusters are held in
place by surrounding vegetation. Others break loose and float about the pond.
The eggs seem to develop properly and hatch in either condition.
The Jefferson Salamander eggs have picked up a covering of
silt washed in from the nearby Township road. This covering may actually
provide a beneficial screen against excessive UV radiation.
The embryos in the cluster are well-developed and probably
within a week of hatching.
Many empty jellies are also floating around the pond, a sign
that a successful hatching has been completed.
Wood Frogs have been calling from the pond for the past
week. New egg clusters appear every night.
Most of the Wood Frog tadpoles will end up as salamander
food. All of the tadpoles, both frog and salamander, will be racing to complete
their metamorphosis before the water of the temporary pond disappears later
this summer.
Facinating stuff! Have to wait awhile for it to start up here though.
ReplyDeleteHi, Stew. It sometimes seems that salamander breeding is over here before it even gets started up your way.
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