Monday, June 20, 2016

Fuglebloggen Fra Follebu-Toppengård (Week 4)

I was out sick for quite a while this week, but I still have news and pictures to post!

Tuesday we measured quite a few nests. It really is incredible how fast these little birds grow up. They start as tiny hairless things and a week or two later and they are full on feathered birds. I also realized I never really explained in full what it is we are doing, where we go, what it looks like and all that. So seeing as I was sick for most of the week I think this post would probably be the one where I describe some of that!

I know I have explained before we have multiple routes, they are named Our Beite, Peter's Beite, Torstein's Pasture, Peters Pasture, Along the Road, Forest 1, and Forest 2. There are a total of around 120 or so Nest Boxes along these paths, some are high up that require a small ladder to reach, some you can stand on nearby rocks, fences, or stumps to look in, others are in boggy areas where you have to hop on grassy patches so you don't sink into the deep mud. We climb up and down the mountain through stinging nettles, rocks, branches and more. There are giant ant hills here that if you take the time to stop and watch you can see the hill practically moving with activity. The ants can be aggressive too, some tuck their abdomen under themselves and charge towards you, and they will bite! They often build their hills at the bases of trees, a few are near trees that have boxes on them.

The purpose of this field research is to gather growth data of three Tit species (Great Tits, Blue Tits, and Coal Tits) as well as European Pied Flycatchers. The data is being recorded by Kathy and her husband Even and sent to their colleagues to be analyzed. We use Calipers to measure the chicks bill (Culmen is another name for it), head, and tarsus. Then we use a wing rule to measure their foot and wing lengths. We make regular nest checks to see how close the eggs are to hatching so that we can get our first measurement when the chicks are a day old and all hatched from their eggs. After that we go back every third or second day to measure again. We keep track of which chick is which by coloring their toes with nail varnish. The Blue Tits can have up to ten chicks in a nest so making sure the colors are redone each time is important so we don't mix up data on the chicks.

There have been a few times where the same color combination has been used on the chicks, there is one nest that had two chicks that were Red and Blue. And another nest wound up with three Blue and Yellow chicks. This can often be because the colors fade off of their toes by the time we go back to the nest so we have to compare the last measurements to the new ones to find which chick matches with the previous and new growth data.

I start my mornings by waking up around 5am to get ready for the day. I take the bus at 7am from Oyer to Follebu where Kathy meets me and we drive over to the field site. We usually have a cup of tea or coffee and discuss which routes we need to check and which nests need to be measured. We set off and make our rounds, stopping around noon for lunch, and hen continuing until all the work for the day is done. We then head back to enter the data and look it over before I head back down to the bus and head home.

We are also going to be studying nesting holes in trees around the study site, but that will be happening later. For now thats about it. The Tit species stay in Norway, but the Pied Flycatchers migrate from SubSaharan Africa. They migrate and nest later than the Tits do, so just now their nests have started hatching. There are only a few nests left that we are waiting for to hatch. The Flycatcher chicks definitely look a little different than the Tit chicks! I'll get more pictures to post of them for next weeks post!

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