Checking the nests - November 9th

Deep in the bush, we continue to visit the nests of warblers, tomtits and robins, usually every three days. Checking the nests is a bit like orienteering. You begin at the hut with the name of a track – say North Cross - and a code – AB02. As you walk along North Cross you will find pink tapes dangling from a tree branches with the codes on them. When you find your code, follow the trail of tapes into the trees until you reach one that has a compass bearing and a distance that pinpoints the nest location.

Chatham Island warbler nest

So far we have found lots of Chatham Island warbler nests which are tear-drop shaped, and woven onto high branches. A fair number of black robin nests have been found too, which are bigger and built lower down, often in holes in old Akeake trees. Both bird species use spider webs as glue to stick the twigs and straw and bark together when they are building, and both line their nests with white feathers that have been shed by the seabirds. There is also the odd blackbird nest floating about, easily distinguishable by its size, and the lack of feathers lining it – perhaps a bird used to warmer climes. The big blue-green eggs are a bit of a giveaway too.

Blackbird nest

One of the jobs that Mel does is a parasite count. If there are lots of fleas in a nest, a bird can get so uncomfortable that she will abandon it. How do you count such tiny creatures? Well, you have to wait until you are back in the lab. But you can catch them. We visit a robin nest in Merlin’s bush, on the east side of the island. Mel hands me the two tiny speckled eggs to keep warm in my palm. Wearing a latex glove, she puts her fingers into the nest for 60 seconds, hoping they will crawl onto her warm hand. She then pulls off the glove, trapping the parasites inside, ready to be counted back in Christchurch. To be on the safe side, Mel treats the nest with a bit of flea powder before we put the eggs safely back for the robin to incubate.

Chatham Island tomtit nest