Streamside Salamanders began hatching about three weeks
ago. Now I’m seeing the larvae in every
part of the creek. The cooler water
temperature of the creek causes these larvae to develop more slowly than their
relatives living in upland pools. While
the salamander larvae in the pond are nearly ready to leave the water, these
creek dwelling larvae will remain in their aquatic environment for several more
weeks.
Each year finds more Streamside Salamanders breeding in the
creek and many have recently begun to utilize the smaller tributaries. I am assuming that the salamander population
has been increasing since stream disturbance, such as cattle access, stopped
when I purchased the property.
Fish do not travel up these small tributaries, so the pool
dwelling salamanders are not threatened by that voracious predator. The down side is the fact that the smaller
tributaries stop flowing earlier in the summer than the main creek. Larvae in the tributaries are at a greater
risk of losing their water supply before they have time enough to develop
sufficiently to adopt a terrestrial lifestyle.
In the main creek, Streamside Salamanders are utilizing most
of the prime breeding rocks. Larvae
hatching from beneath large flat rocks in the fast moving stream reaches are
swept into the quiet waters of downstream pools.
Streamside Salamanders are now numerous enough that each set
of riffles produces some larvae for the adjoining pool.
Larvae of this species develop a more streamlined shape than
species living in quiet ponds. Even in
the pools, the water can sometimes move quite swiftly and the larvae need to
keep from being swept away. Their long,
thin shape helps the larvae settle in and ride out times of storm runoff.
Even the gills appear to be stouter and more compact. We’ve had plenty of rain this spring and the
water table is high. The creek should
keep flowing well past the time that the salamanders lose their gills and move
away into the surrounding woodland.
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