Practice Netting and Banding

7FEB2012

Today was the first day in the field. My boss, Becky drove us out to our work site at Manning Mountain. Melissa, Kelsey, and I rode with Becky, Jie rode with Nathan, and Julie showed up later. Manning Mountain is about 10 miles away from the office in the Ft. Hood cantonment area. We passed bazooka ranges and Middle Eastern-themed urban assault courses. It looked like the Call of Duty video game. We drove off-road to a nice spot and spent the whole day practicing extracting and processing birds.

There were about 16 mist nets were set up in box patterns around bird feeders filled with seed. We filled the feeders, opened the nets, and retreated to the trucks for 40 minute intervals to wait while the birds fell for our trap. We caught about 30 birds that day including Chipping Sparrows, Slate-colored Dark-eyed Juncos, American Goldfinches (so tiny!). We also caught a Field Sparrow, a Brown Creeper, and a Black-crested Titmouse! I’ve seen Tufted Titmice before, but these ones were a little more funny looking with their black coloration on their head. And always with the yelling! They’re never happy to be caught or handled.

A little about the mist nets: The nets are 6 or 12m by 2m and are composed of thin thread. They each have 4 tiers, which are divided by 5 lines that run the span of the net ending in a trammel. The trammels are looped through two poles on either end which are fit into a stand on either end. There are two trammels on the bottom pole and three on the top. In the middle is a connecting piece with a length of rope attached to it which is anchored to the ground by a large rock. When the trammels are spread out, I am left with a 12 or 24 square meter area of bird trap. To close the nets, I simply group all the trammels together.

Extracting birds from the nets can be difficult. It doesn’t have to be; sometimes it’s exceedingly simple, but other times a bad tangle can leave me frustrated for the rest of the day. The procedure I have adopted is such: Free one wing, unloop the head, free the other wing, free the legs. This is just a guideline; I sometimes go in a different order depending on the type of tangle or if the bird is a biter coughcardinalscough. The wings can be tricky because I need to get them back through the square they came through and sometimes this procedure can be hampered by other parts of the net getting caught in the flight feathers or tension from another tangled part of the body like the feet. Especially the feet. The head can be tricky because it’s hard to see what loop the head went through. A general pull will usually take the head out, but sometimes the angle is messed up and you end up putting the bird’s head through another loop and have to “take his sweater off” several times before it’s completely free.  After these first two steps, the second wing and feet are usually a breeze. Feet are untangled by gently massaging the toes back and forth while simultaneously pulling the net off of them. The massaging motion uncurls the toes so you can pull the net right off. Once again, this can be made tricky by birds with strong, curved toes and claws, usually things that need good grip on trees such as woodpeckers, nuthatches, and blue jays. Once the bird is free from the net, you can deposit it in a bird bag, tie the drawstring, and clip a numbered clothespin on it to denote the net you captured the bird in. I have seen nets with as few as zero birds (several runs in a row) to seven birds, and you can catch even more. For now we are “passive netting,” meaning we leave the nets up and walk away and see what we catch. When the Golden-cheek Warblers come back from migration in Mexico we will use a technique called “target netting”. Target netting involves identifying an individual bird you wish to catch, and playing an audio recording of GCWA vocalizations to rile up the bird to fly into your net.

After taking the birds out of the net, we placed them into small cloth bags to literally hang out until we were ready to process them. We took the birds out of the bag and practiced holding them with the bander’s grip and the photographer’s grip. To use the bander’s grip we held with the bird with our index and middle finger around the birds neck so that the head is sticking through the little gap between the lower portion of the our fingers. This keeps the bird safe and steady in the hand. First thing’s first, we applied a USGS band around one of the bird’s legs. This aluminum band can be recovered by other bird researchers so the information of where the bird was caught and when can be shared with other agencies and groups. We also practiced applying color bands, but since these sparrows, titmice, and such are not our focal species, we don’t have a permit to leave them color banded, so we also got some practice taking OFF the color bands. We also practiced aging our birds. For these practice birds we utilized a book called “Guide to North American Birds” by Peter Pyle. This book is a reference to identify, age, and sex most North American passerines. We looked at the differences between the color, sheen, and wear of certain feather tracts to figure out how old they are. For reasons that take a little while to explain, we can generally only age the birds as “hatching year,” “second year,” or “after second year,” although they can be much older than two years old. Sparrows regularly live to be ten years old or more! When we finally start catching GCWAs, we will be using a much more precise guide compiled by Becky herself. The added detail will make it much easier to be accurate in aging these birds. Once we’ve gone through the procedure, the practice birds are free to go. They get to keep their USGS bling as a thank you gift for being so polite and generous. Of course, some can’t resist the free food and end up coming back sooner or later.

After a long day spent banding, gabbing, and snacking (not on the birds of course), we piled back into the trucks and headed back to the office. I feel confident that my previous work experience has prepared me well for the banding portion of this job. I am excited for the GCWAs to arrive so we may begin banding and tracking them. Once the females find a mate, they’ll begin building nests, so I’ll learn how to spot those as well.