Season changes, weather changes, local avifauna changes.
We’ve been watching the departure of summer birds- the
yellows and reds and blues- and welcoming in our winter visitors… with all of
their browns and tans and light browns. Of course, with the winter arrivals,
we’re changing where we look for the birds. No more warbler neck!, but
confounded by little brown jobs in the bushes.
 |
| You'll miss me when I'm gone! |
Tracking this movement has been a difficult proposition- we
talked before about radar ornithology previously. And
the same holds true in the fall: Large migrations can be tracked by radar in
the fall too.
But that’s not the only way birds are being tracked these
days. Lots of new technology has yielded new ways to follow individual birds
year-round along their migrations.
We’re probably aware of the most involved migration
tracking… Whooping Cranes and
ultra-light aircraft. They have a pretty cool blog about their on-going efforts
to get the next generation down to the wintering grounds: Blog and Whooper-Cam.
 |
| You don't need to follow me! I know where I'm going!... Robertson County, right? |
This is of course a special case- spectacular effort and
results- but not feasible with most any other bird.
Researchers have been using a number of other devices to
track birds now. John and Helen Baines talked to us a while back about tracking
Osprey from the Lake District
of England over the Mediterranean and across the Sahara Desert to their
wintering grounds. There are a number of other Osprey tracking projects from North
America and Europe that generate similar data. It’s pretty cool to watch
these birds cruise around their part of the world, operating on their own
schedules, flying where they feel is the best.
In general, these tracking devices are some kind of GPS
logger that are either glued to the bird’s back feathers or attached
by a harness. Either way the unit has to be light weight, since you know-
they still have to fly.
This type of technology is applicable to all kinds of larger
birds- there’s numerous efforts to track Peregrine
Falcons, Black and
Turkey Vultures, and pretty much anything else that’s big enough to
tolerate a couple of extra ounces on their back. I’ll make a special note about
this one Peregrine called “Island
Girl.” She’s on her way back down to Chile after spending the summer north
of the Hudson Bay! She just cruised over the Gulf of Mexico in two days of
flight from the Florida Panhandle to Boca del Rio, Mexico. No big deal. Looks
like she found a resting spot somewhere out in the middle of the water on
05October… maybe a big boat or an oil rig.
 |
| Not Island Girl, but maybe one of her friends! |
As we all know, as technology progresses, it also gets
smaller. The holds true for phones (well, used to hold true for phones) and the
devices used for tracking birds. There are now miniature versions of the
geo-trackers that the hawks wear that can be attached to smaller birds! A quick
search around the internet found oodles of examples- Wood
Thrushes coming across the Gulf of Mexico (with open
access peer reviewed paper), European
Woodcocks heading east (or north!), Whimbrels, Bar-tailed
Godwits, and Arctic
Terns.
The Arctic Tern work made quite a splash when it was
publicized (and published)
several years ago. This new technology shed a great deal of light on the
migration patterns of these mostly ocean-bound birds. Importantly, it
identified areas in the middle of the ocean that served as refueling areas for
these birds… something that may seem self-evident, but had not been documented
previously. This certainly stresses the need for conservation and further study
of the ocean systems! What’s also quite impressive is the technique used for
this study. Instead of tracking the birds remotely by GPS unit and satellite,
they strapped a small
geolocator to the bird’s leg and let her go. To recover the data, they had
to recover the bird! Talk about holding your breath! But it worked!
 |
Interpolated geolocation tracks of 11 Arctic terns tracked from breeding colonies in Greenland (n = 10 birds) and Iceland (n = 1 bird). Green = autumn (postbreeding) migration (August–November), red = winter range (December–March), and yellow = spring (return) migration (April–May). Two southbound migration routes were adopted in the South Atlantic, either (A) West African coast (n = 7 birds) or (B) Brazilian coast. Dotted lines link locations during the equinoxes.
From: Egevang C et al. PNAS 2010;107:2978-2981. ©2010 by National Academy of Sciences
|
So in a world with all of this new high-tech tracking and
self-reporting positional data, you might think there’s not a place for the
average birder to help out. But you’d be wrong! Not everyone gets fancy
schmancy GPS trackers- most groups still rely on good old-fashioned bands to mark
their birds. These bands can be color-coated on
the legs, patagial tags on their wings, or neck bands.
If you see a banded bird, you can report it to the USGS North American Bird Banding Program.
If you see a Trumpeter Swan in the Brazos Valley (banded or otherwise), report
it to me first though. J
Another way you can help with tracking bird migration is get
out and bird! And then report your sightings to Ebird. Ornithologists and citizen
scientists can use the data compiled by Ebird to analyze migration patterns and
population densities, or look at geographic coverage of birding hotspots in a
county. It’s a convenient and powerful tool for professionals and amateurs
alike!
No comments:
Post a Comment