This time of year the deepest part of our swale usually becomes a vernal pool, and Ed and Zelda visit the pool a few times a day for a swim and a meal.
A vernal pool is ephemeral, much like many of the spring natives in our garden. That is, it's temporary, lasting only a short time, and returning year after year. They are low spots in the land where snow melt and spring rains collect, and they're usually dry, or mostly dry during summer and fall.
Vernal pools usually contain no fish, making them mostly free of predators and allowing a place for amphibians like toads and frogs to visit and lay their eggs. With enough rain our vernal pool stays full long enough for tadpoles to fully develop into young adults able to walk, hop, and breathe on land. The years when we have toads in the garden are generally years when we've had a lot of snow, and a normal amount of spring rain, and our vernal pool lasts at least several weeks before going dry.
This year so far, we've had neither a normal amount of snow, nor much in the way of rain. As it was in much of the country, March was unusually warm and dry here. So far, April has been more seasonal temperature-wise, but we're still very short on rain. What this will mean, if anything, for the rest of the year remains to be seen.
For Ed and Zelda though, it has meant not much to eat in the swale. They waltzed past the dry, deepest part of the swale to this area which is always moist. They dipped their bills into the murky water a few times, and appeared to find something to eat.
Since they wouldn't have seen water from air as they were flying over, the fact that they stopped here anyway makes me wonder. I like to pretend Ed and Zelda are the same pair of mallards that return here to feed and swim every spring. Maybe they really are, and maybe that's why they landed, expecting to find the usual vernal pool. Or, maybe there's some instinctual behavior passed down through generations like our GPS navigators in our cars, so that even young birds who've never been here, somehow know their parents were.
There's been a lot of talk about global warming during the winter that wasn't and the record-high March temperatures. Whatever the facts are, I felt a little sad for Ed and Zelda, and wonder what temperatures and how much rain this summer will bring. All I know right now is there was no place here to swim, and not much for them to eat. This spring, as happy as I am to see them, Ed and Zelda are just passing through.
