Monday, July 27, 2009

Alaska - the nests & chicks

While wandering across the tundra on the hunt for godwit nests we would regularly stumble across nests of other birds. Often this discovery arose following the heart-stopping flush of bird from the nest as we stepped only centimetres away. Ptarmigan often gave the most dramatic flush from the nest. Nest discoveries sometimes proved useful for other researchers in the area at the time, such as those working on Short-eared Owls or Pacific Golden Plovers. The size of a clutch would vary - all Godwit nests we found had 4 eggs, long-tailed Jaegers 2 eggs, but Ptarmigan nests typically had over 10 eggs, the largest I found had 14. There was also a variety of nest type and colouration of eggs. Here's a few examples

Ptarmigan Nest

Godwit Nest

Short-eared Owl Nest

We were also fortunate enough to still be around as the chicks hatched. It was always a delightful sight seeing a chick bumbling its way across the tundra, in the company of the adult or hunkered down on a nest.

Short-eared Owl

Of particular interest was the fact that due to the abundance of voles and lemmings the clutches of some birds, such as Rough-legged hawks, was unusually large. In the photo below you can see a picture of a Rough-legged hawk chick, one of 6 in the nest. According to Ted Swem, a biologist who has been studying rough-legged hawks for 25 years, the typical clutch is 2-3. He had seen only two clutches of 6 in the past 25 years.

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