Tuesday, October 13, 2015

October means time for "Toots" all night long...

It's finally October once again!  With the cold air coming back also brings with it the migration of many bird species.  By mid-August I said goodbye to my Bank Swallows and other species of swallows, then in September the warblers began to come and go.  While many species are still on their way out to warmer places...many species are beginning to make appearance such as waterfowl and owls!

For those of you who have read my blog since last year know that I am involved in Trent University's owl banding program.  Every year at the James Oliver Ecology Centre, near Bobcaygeon, banders come to this site nightly and see what we can catch.  This year, we have added a new site to our banding list (it'll be referred to as the Sisson Property).

Banding a Screech Owl at the Sisson Property
Nets are set up throughout the forest and calls are played.  The calls cause some interest in the owls, drawing them to come closer and fly into the nets where we then catch them and process them.  We collect a variety of information such as: Weight, fat levels, wing length, sex, and age.  Aging the bird can be an especially fun process as we often are able to use a blacklight to determine it.  The black light will pick up on traces of pigment left in the feathers showing a pinkish colour (it feels very much like CSI!).  Young birds will have all new feathers, meaning that under black-light all the feathers will have a pink tone to them.  As a bird ages and feathers become older, they will be white under the light.  After second year birds will be a mismatch of pink and white as wing feathers will be a both old and new, being replaced as need be.  For example..we have two photos below!  The first is using a blacklight.  We can see that while some feathers are pink (new) there are a few random feathers that are white (older), this makes this bird an After Second Year (or ASY) bird, meaning that we know it is at least two years old.

Using a Blacklight to determine age (AHY)

This second photo, we are not using a black light. However, if you look closely you can see that feathers at the beginning and at the end of the wing are a slightly darker colour than those in the middle. This means that they are newer feathers! Being in this placement means this lovely lady was a second year bird.

Aging a Saw-whet Owl without a blacklight (SY)
There will be two main types of owls we will likely catch at these sites.  The first owl is the smallest owl in Ontario (and one of the cutest!). Saw-whet Owls are Especially known for their "toot toot" calls and big yellow eyes. When in distress, they will often raise small ear tufts and elongate to look more branch-like, which comes in handy when trying to hide from a predator.  These little guys are the most popular to catch at the Oliver Centre.

The second owl we will likely catch some of is the Eastern Screech Owl.  These little guys are populat to catch at our Sisson Property, but are not uncommon at the Oliver Centre either.  Screech Owls can be coloured with either a grey morph (like the one pictured below) or in a red morph.  Screech owls are larger than their Saw-whet cousins, have visible ear tufts, and also have a very cool "whirly" call.

We are really excited to be back out and catching these little guys throughout the rest of the month!!

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