Weekly Reports

After all that talk in my last article about being crazy busy this week, I am astonished to report that we have already (miraculously?) pulled through it. We finished our first round of MAPS banding, Richard outfitted ten Canada Warblers with radio transmitters and coloured banded many more up in High Prairie and Kevin Fraser and I (with the amazing assistance of Judith from Canadian Wildlife Services and Amélie and Kevin of Beaverhill Bird Observatory) got out all 40 of Kevin’s geolocators; this was done with an efficiency that had everyone involved a little flabbergasted. To quote Kevin: “CAWAbunga!” (This is hilarious, albeit incredibly cheesy, if you know that CAWA is the shorthand code for Canada warbler, and have an affinity towards puns). Catching birds for transmitters or geolocators is a very different process than our regular netting. During migration and MAPS we are using passive netting, meaning our nets are just strung up in the forest and birds that happen to fly into them are caught and banded. For research that requires equipping something to a bird, we use a technique called target banding. As the name implies, target banding is used any time we want to target specific birds; we don’t want just any bird flying around the forest, we only want male Canada warblers. The premise is simple, we walk around in areas of prime Canada warbler habitat and listen for the males singing. Once we locate the bird, we set up a short net near its singing location in thick cover and place a stereo playing the Canada warbler’s song beneath it. Breeding birds of all species are incredibly territorial. Playing the song of a specific species in the presence of that species will compel it to fly in and try to locate and attack the interloper. Essentially target banding is capitalizing on this aggressive behaviour. Often this works better in theory than in practice – you may inadvertently set the net on the edge of its territory which it doesn’t actively defend, or if there is insufficient cover or perches of the right height the bird will come in and continually pass over top of the net. Not this week though, either Richard and I have mastered net placement or we were just lucky, but whatever the case, we had success at almost every set-up. Target banding involves quite a bit of walking around looking/listening for birds. With all that tromping around the forest it’s been hard not to feel sorry for the poor defoliated trees this year. I have never seen forest tent caterpillars this thick! When you sit quietly in the bush you can literally hear them chewing above you. In the time it takes us to process a bird, our data sheets get peppered with their droppings. Although this sheer volume of caterpillars is kind of gross, they provide food to many wildlife species and can actually be good for the forest in the long run. By stripping the trees of their leaves, they open up the canopy and allow sunlight to reach the forest floor. This, coupled with their nutrient rich droppings, helps to fuel the growth of young trees and shrubs creating a mature forest with a thickened understory which is extremely good habitat to all manners of birds and wildlife.