a very small vernal pool: would woodland amphibians use it?
I built a very large garden pond on my property: a 1/4-acre native plant, densely landscaped lot in an urban area. There are nearly NO woodfrogs, toads, tree frogs or woodland salamanders around due to residential development. (There is a population of redback salamanders on my property and in the adjacent wooded lots; these do not rely on pools for breeding, however.)
I'm considering building a very small vernal pond (6' x 5' x 2') on my property. Would this be too small for woodfrogs, toads, aquatic-breeding salamanders, spring peeper woodfrogs, etc. to use? (Perhaps after being introduced into it as larvae/eggs and returning to breed in it?) I'd plumb a valve to the the liner so that water only stands in the spring.
(I feel that they would not use the closed-system, 38' pond in my yard because there are fish in there, as well as a current of moving water. Also, I read that permanent ponds (especially those containing fish) are less suitable for vernal pond-breeding amphibians due to the presence of a certain bacteria.)
Would I be better off using the spot to build a cranberry/carnivorous plant bog, than wasting it on amphibians that won't use it?