Birding with Explosives

This past week, we went out on the leks (sage grouse breeding grounds) to trap birds so we could color band them and get measurements and blood samples. And sage grouse are not captured like songbirds, by hanging mist nets and waiting for birds to fly in. Grouse are trapped with rocket nets (yes, there are actual rockets involved). The day before we went out and set up a 100 foot long net along one side of the lek. One edge is staked to the ground, the other is attached to a number of rockets which are loaded with explosives. The next morning we head down to the lek before the birds, before dawn, and before we are fully awake. When there are birds in the capture area, the detonator is pushed, the rockets go of with loud bangs and spew out fire as they hurl the net through the air and over the birds.

We all run frantically down to the net, where we throw towels over the birds to keep them calm, then extract them from the net and put them in cardboard boxes. Our boxes were big moving boxes from Uhaul, and I think they recommended using them for blankets, rather than birds. First we drew blood from the birds, which will be used later to look at genetics and fitness. During this process, some of the blood ended up on us instead of in the capillary tubes, so I now know that cold water washing machine cycles are the most effective for getting blood off your clothes.


After the blood had been taken, each bird got color bands so we can identify individuals later when we do our morning observations.

We aged the birds by looking at their primary flight feathers (juveniles are pointy, adults rounded), took a few measurements, and put the birds into pillowcases to weigh them.


Sage grouse males are quite bizarre and interesting, and when displaying can look a bit more like alien creatures than birds. The yellow patch on this bird is an air sac which is part of his esophagus. When doing their breeding displays, the can inflate these air pouches as the strut, fan their tails, and make odd noises (they sound a bit like pigs). The white feathers around the yellow patches are stiff, and the birds rub their wing feathers against them to produce sounds too, just like a grasshopper or cricket.

And we released them, and they took off flying or strutting into the sagebrush.


And now, we have some sage grouse blood samples in our fridge alongside the milk and eggs and vegetables.