2013 Migration Continues

Nature Notes for April 26, 2013

Although most migrants are arriving back at the expected times, every migration season brings some surprises. Perhaps the birds were most surprised by the ice storm on April 11. No doubt some early migrants perished when the cold temperatures suppressed insect activity and locked up available fruit in ice. Some may even have flown back south, in what is termed a reverse migration, to wait for more agreeable weather.

In April, birders’ focus shifts from waterbirds to landbirds. Throughout most of Northumberland, wet fields that were teeming with ducks, geese and swans in March have dried out, so the fields are no longer suitable habitat for these birds. As well, lakes to the north are now ice free, so these birds can continue their northward journey.

Southern Ontario has experienced some very strong southerly winds which have blown some vagrants our way. Ontbirds, the listserv of the Ontario Field Ornithologists, has been buzzing with reports of Blue Grosbeaks on the Ojibway Prairie in southwestern Ontario, a White-eyed Vireo at Tommy Thompson Park in Toronto and a Worm-eating Warbler in Peterborough. None of these species normally range this far north.

Locally, three Worm-eating Warblers visited a garden just north of Cobourg, but didn’t stay for very long. Another southerner, a Snowy Egret, turned up on a pond in Ward 2 of Port Hope. This bird stayed for several days and allowed many birders the opportunity to see it.

Several swallow species have returned to the area in good numbers. Some had arrived before last week’s ice storm, but may not have survived it. I visited one of my nest box sites in neighbouring Durham Region today (April 23) and found most boxes being vigorously defended by Tree Swallows. Barn, Bank and NorthernRough-winged Swallows could be found last weekend along the lakeshore. The clouds of tiny midges, that many people are finding annoying, are a banquet for these birds.

Several species of sparrows, such as White-throated Sparrow, Dark-eyed Junco and FieldSparrows can also be found feeding on these midges in the tops of trees in the sun. It always seems a bit odd to find these birds so high up, since they usually feed on the ground. They go where the food is.

The first warbler to arrive in my neighbourhood in Port Hope is the Yellow-rumpedWarbler. Although I haven’t seen one yet, I have heard them singing. Both Golden-crowned and Ruby-crowned Kinglets have been moving through. Both of these species are tiny birds, weighing only about 6 gm. Both have quite big songs for the size of the bird, although the Ruby-crowned Kinglet has the longer more complicated one.

Last Sunday, April 21, my husband and I found a Broad-winged Hawk along a section of the Ganaraska Trail in rural Port Hope. Broad-wings are a forest hawk that winter in Central and South America. They are only now arriving back in Ontario.

This one must have been hungry, since he flew along quite close to the trail and perched in a tree only about 20 feet away from us. In a small pond beside the trail, a few Wood Frogs had started calling. Their singing had drawn the attention of the hawk. It sat there for quite a while, perhaps trying to see a route through the tree branches to reach the pond and perhaps dinner. We stood and watched for perhaps as much as ten minutes before the bird flew off again. I wouldn’t be surprised if it circled back and tried again to find a way to the pond. Although the prey of Broad-winged Hawks is primarily small mammals, like most predators, they will eat anything they can catch.

Within the next month, spring migration will peak. If the spring remains stormy, we may find some more unusual birds, along with the expected species.