It is starting to feel autumney out there. The leaves are beginning to turn and the air has become decidedly crisp early in the morning; which isn’t all that early anymore. We start monitoring half an hour before sunrise, so the later we get in the season the later we start. No more 4:30 start times, now we are starting at a fairly normal working time of 6:00. And it will only get later and later until the season ends at the end of September.
Along with the fall weather, the fall birds are showing up. American pipit, grey-cheeked thrush, white-crowned sparrow and orange-crowned warbler have all begun trickling in from the north. And as they trickle in the last of many other species trickle out. Generally this ‘switch-over’ time is quite slow for us, but this year, so far, things have remained pretty steady. Over the past two weeks we have had some slow days, but we have also had quite a few days with capture totals over fifty. Swainson’s thrush are easily the most common species we have been catching and since I last updated you on the top banded species they have moved from fifth to first place.
Other common species in the nets this past week have been Wilson’s warbler, white-throated sparrow (who are having another unexpected burst of migration), myrtle warbler, sharp-shinned hawk and alder flycatcher. Some less common species that have impacted our totals very little but have pushed up our fall diversity were a LeConte’s sparrow, a pair of blue-headed vireo, a downy woodpecker, and the most surprising – a pileated woodpecker. All four of those species are not uncommon in the area, but certainly aren’t givens in the nets.
Also coming with autumn proper is owl banding season. From September 1 to mid-late October I will be out every night calling for northern saw-whet and boreal owls at a net array set up near the Boreal Centre. We have been doing the owl banding since 2004 and we average about 100 owls a year. That isn’t a lot when compared to songbird banding, but we have had some interesting recaptures over the years and data is short from western/northern stations so every little bit counts.
Aside from the obvious difference of it happening at night, owl banding differs from songbird banding in one major way and that is we do active netting as opposed to passive netting. At the Bird Observatory we have a lot of nets set up in slightly different habitats and we do not use any lures to attract birds to the area. We simply catch what we catch so we can get an unbiased sampling of what is moving through. For owls we are trying to target two specific species that are migratory and small and easy to handle and so we play calls to attract them to the areas where our nets are set. This means we can set fewer nets while still being able to accurately sample the number of owls migrating locally.