Above: After Second Year Male White-winged Crossbill – check out the overlapping beak
Things are getting busy at the Lesser Slave Lake Bird Observatory with the start up of the Fall Migration Monitoring Program on July 12th. While some birds are already showing signs of migratory behaviour, many birds around the station are still actively raising their families as we finish up our MAPS program (Monitoring Avian Productivity and Survivorship) over the next few weeks. MAPS monitors the status of breeding birds at four sites around the LSLBO each summer, and this week the banders had a special highlight! It was a family affair as a family of White-winged Crossbills (adult male, female and juvenile) were captured together at the same time and in the same net during one of our MAPS rounds representing only the 2nd, 3rd, and 4th White-winged Crossbills ever banded by the LSLBO. The only other White-winged Crossbill that we have banded was during fall migration monitoring way back in 2000. Although flocks of White-winged Crossbills are commonly observed flying over the station during the summer, they prefer coniferous habitat as opposed to the mostly deciduous forests around the LSLBO. So we rarely have the opportunity to actually band these beautiful birds. Capturing this young juvenile crossbill with its parents highlights the fact that adult birds will care for their fledglings long after they have left the nest until they are fully independent.
Above: After-Second year female White-winged Crossbill
White-winged Crossbills are pretty easy for birders to ID. The males are a beautiful reddish-pink colour while the females have a dusty yellow plumage. Besides their white wing bars, they can also be identified by their very distinctive crossed bill (hence their name). Red Crossbills are another species of crossbills that we see in the area, but they lack the white wing bars and the males are much redder in colour. Both species primarily eat spruce and fir seeds, so their uniquely curved, overlapping beak shape enables them to pry open the scales on cones and extract the tasty seeds with their tongue. It is the ultimate multi-tool.
White-winged crossbills are year-round residents in the boreal forest, but they will travel great distances in search of abundant cone crops. Some years we will see them everywhere, and other years they seem to “vanish” as these little nomads move on to new areas in search of food. They may also communicate with each other about cone crops to help identify the location of trees with the best seeds. White-winged Crossbills will usually begin breeding very early in the season, even as early as the late winter. However, researchers have recorded them nesting in all months of the year, whenever food is plentiful. Run into a bumper crop of cones, and they will start singing and breeding at anytime to take advantage of these abundant food resources.
Above: Juvenile White-winged Crossbill
With the start up of Fall Migration Monitoring, the LSLBO will be hosting public tours over the summer on most Wednesday and Saturday mornings. Pre-registration is required for these family friendly programs, so contact the Boreal Centre for Bird Conservation at 780-849-8240 or email info@borealbirdcentre.ca to sign up for a tour.
By Patti Campsall – Executive Director
