Faster than we thought

This wood thrush is not a grassland bird, but I have found them in the woods that border a lake north of our place in the country. The wood thrush is an eastern forest songbird that
Canada's Bridget Stutchbury has been studying. Stutchbury has made some important discoveries in her forest songbird research site in north-western Pennsylvania, but none perhaps as exciting as the most recent one, published in February 13th's edition of Science. (You can listen to Bridget on today's Quirks & Quarks here or read this piece on the National Geographic news site.)

By putting tiny "geolocators" on the backs of wood thrushes and purple martins, Stutchbury and her team have found a way to track small birds to their wintering grounds and learn their individual migration routes. Here is what they look like.

These devices do not use the customary satellite telemetry, but instead detect and record sunrise and sunset times with a degree of accuracy that allows the researchers to match the times to the location where each bird must have been on that day.
Stutchbury, who is the Canada Research Chair in Ecology and Conservation Biology at York University, participated in a teleconference arranged by the National Geographic Society. She said that one of the big surprises was just how fast the birds flew north in spring. The best research up till now has estimated speeds of 150 to 250 kms per day, but the birds carrying the geolocators were averaging 500 kms per day. One purple martin made it back from Brazil in 13 days.

This new way of tracking songbirds should help researchers locate the wintering sites and migration routes of declining species to look for causes away from breeding areas. Grassland bird researchers could use them as well.