All across the region, birders are discussing how slow the beginning of this year's migration seems to be. I birded at Intervale Lowlands in Lake Placid earlier this week and found things to be fairly slow in terms of migrants there - as has been case in the other locations I've been. Yellow-rumped warblers have been around for weeks now, and they were in good numbers. We also found quite a few Nashville warblers and a variety of other resident birds and early migrants. Highlights also included nesting American kestrels and hooded mergansers as well as a broad-winged hawk.

But otherwise there were very few migrants. It was the same scenario which I noticed at Crown Point earlier this week and about which I wrote for the Champlain Region. After all, birders across the northeast are commenting and complaining about the dearth of migrants. The weather pattern which was in place here for so long appears to be to blame. A high pressure system sat in the northeast – flooding us with warmth and sunshine, but blocking a low pressure system that was hammering the south with storms and rain. Our migrants were blocked by all that inclement weather after they crossed the Gulf of Mexico or flew in from the islands of the Caribbean.

Hooded Mergansers Larry
Hooded mergansers are once again breeding along the AuSable River at Intervale Lowlands. Photo courtesy of www.masterimages.org.

This theory seems to be corroborated by reports in places such as Florida and Texas where good numbers of warblers and other migrants were being found. In fact, a report out of Texas in late April noted that many migrants were trapped and harried by severe storms which had downed them after their long crossing of the Gulf. Some birds were undoubtedly killed by the storm – head winds can be lethal as the birds fly over long stretches of water.

And so it appears our birds have been bottled up. But, as our high pressure weakened and slid north, allowing in our first rain in a couple weeks, I've already noticed a few changes. For instance, the large numbers of white-throated sparrows (which included a lone Lincoln's sparrow) which had been feeding in my yard have largely moved on, pushed through by the moving air masses. There are now growing numbers of white-crowned sparrows around, newly arrived from the south. And in the past few days I've had my first warbling vireo, black-throated green warbler, Cape May warbler (oddly enough it was evidently an early arrival record for Franklin County), black and white warbler, and ovenbird of the year.

white-crowned sparrow
Since the weather pushed through, white-crowned sparrows have started showing up in the area on their way north.

And so it is that there are many factors which play into the arrival dates of our birds, including local weather patterns, global weather patterns, and the genetically controlled instincts of individual species. But how all these elements work together is uncertain. Bird migration does hinge on a variety of things – including weather. And as theories of climate change continue to develop, it is likely that migration patterns could change too. For one, some folks theorize that climate change could push migration earlier. After all, the early, warm spring we had last year did appear to bring some short distance migrants or local migrants like blackbirds, song sparrows, and American woodcocks up here a little sooner. But birds wintering in the tropics are not directly aware of what the weather is like in the Adirondacks. The timing of their migration is more genetically hard wired to cues such as day length – or so we think. So in this author's opinion, the connection between the arrival date of Neotropical migrants and climate change is much harder to create. Such changes may occur, but they will theoretically take a long time to develop. How long that takes and what those changes might look like is anyone's guess.

And then of course there are seasonal weather patterns like the rain in the south this year which will likely vary greatly from year to year. It is all very intriguing and makes for good fodder for birding discussions every year. And birders are often surprised just how close many species come to their usual arrival dates – even in years when migration is sluggish to start. After all, the drive to breed compels the birds north eventually. And so despite what seems to be a slow beginning to the migration this year, our birds will come. It's just a matter of time.