Monday, 8 October 2012

The Birds.

We have a few different games to play in the car. A particular favourite is called Canada Flag Ahoy. It’s a complicated game where if you see a Canadian flag you have to yell “Canada Flag Ahoy” at the top of your lungs before your sister does. But driving also offers the opportunity to stare out the window and take in some of the things you wouldn’t necessarily notice and ask a bajillion questions about them in the five minute drive to school. It’s fall here now so we’ve talked about why leaves change, why the geese need to yell while flying, where all the butterflies went and if they will they see the geese when they get there. 

The girls have noticed a lot of species are on the move south this time of year, including their grandparents, and we’ve been talking a lot about which species stay, which go and how they get to where they are going. This brings me to my real topic. 

Bird Shows.

Some species gather in large numbers around this time of year to prepare for migration. I have spent a number Augusts and Septembers with a VHF receiver driving the shorelines of Lake Erie listening for my tagged Black Terns within in the hundreds staging. I’ve inspected hundreds of Great Egret legs standing on mudflats looking for the little red bands we’d put on a couple hundred kilometers away.  Birds do some significant travelling this time of year and even birds know a road trip is more fun with a buddy, or a couple of thousand buddies.

What we usually see here on our way to school are robins, blackbirds and starlings. They are putting on some impressive displays rivalling the snowbirds at the air show (and sometimes just as loud). There’s a few old trees out behind our place that are a favourite roosting spot, so luckily we get to witness quite a few bird shows. I’m sure you’ve all seen the large flocks seemingly moving as one unit, changing direction and then all suddenly landing. In late summer a number of species join flocks, they fly together, feed together, roost together and migrate together. These staging flocks can be tens of thousands of birds (although not that many fit on the trees in our neighbourhood). Nobody quite knows yet all of the hows or whys, but that doesn't make it any less stunning. 

A video of this phenomenon in starlings (as a bonus it's a nice wetland restoration story too):

And just to make this post extra awesome - did you know that the larger flocks actually show up on weather radar? And that since the discovery that the strange ghosting patterns that kept showing up on screens were actually birds migrating it’s been tracked (thank you fellow science nerds).  Now even the air force uses it to avoid collisions! Bunny was thrilled to know that you can track insects too and is planning to watch for her beloved butterflies to return in the spring (OK – it’s not that good, you can just see swarms, but we’ll pretend they are butterflies). Now instead of trying to describe all this I will let some of the ridiculously cool images speak for themselves:

Dispersal at Sunset:

Roost rings as the flocks depart:

More information and pictures here: (which is where the above images are from) 

I wonder if they play games on the way down. We should teach them Canada Flag Ahoy.

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