The Vernal Pool

During our trip to St. Catharines Ontario, two weekends ago, we toured several woodlots on Sunday. During one of the tours we were introduced to the concept of the vernal pool a visited a few that were purposely designed as such in a reforested field that used to be farmed. Vernal as in vernal equinox I presume implies seasonal or that it dries out at least once yearly. We learnt that a vernal pool will support a unique habitat. The process of drying will not let certain plant and animal species survive in a vernal pool that would otherwise survive in a continually filled pool for example fish. This means that certain species which cannot cohabit with for example fish can survive in a vernal pool. These species include virtually all amphibians including many frog species and salamanders and bugs.

We have many amphibian here on our property and I know of a couple of pools that dry up each year. There is a swale or shallow ditch that is only full in the springtime. I imagine that these pools must have actually contributed to and provided the ideal conditions for the abundance of frogs in this woodlot.