14 March finds me stopping to admire the sunset across the flooded fields that we call "north of deButte's on County Road 18, 1.5 km NNE of Bishops Mills." The Ash trees along the fencerow draw a spidery black filigree against the luminous sky, and the last drifts of snow reflect the evening blue in a vibrant contrast.
I love to see these fields flooded by the creek each spring. We've been monitoring Leopard Frog migration here since 1987. Every year the frogs move a kilometre from their hibernation sites in Middle Creek to the South Branch, where they breed. Their routes vary depending on conditions - in high-water years the movement is centred on the overflow from Middle Creek to the South Branch, but on dry springs when there is little or no flow through the culvert, it's a kilometre north of there, where the creeks are closer together.
At coming-home-from-work time on 18 March, Fred went out to check the site I'd photographed, and found about 10 cm of water above the tops of the double culverts, being sucked into them in twin vortices. He walked 100 m on both sides of the road, seeing neither fish nor Leopard Frogs; it was probably too windy for any frogs to be at the waterline, and too cold for Perch to be moving yet. Lots of fine landsnail-rich drift was accumulating on the waterline; an advantage of submerged culverts with vortices is that they don't sweep the floating drift downstream, and since 1993 this has been one of our most reliable drift sampling sites.
When he came back from Mudpuppy Night that evening, after the water in the flooding creek in Oxford Mills had measured 1°C, he found that the water here was 4°C, since with huge flooded fields as solar collectors, the water was probably as warm here as anywheres, but probably not warm enough to motivate migration in either the fish (primarily Perch) or the frogs.