LUTHER MARSH - A group of researchers has been spending the past three weeks capturing, tagging and fitting a small songbird known as a bobolink with geolocators. Headed up by biologist Rosalind Renfrew of the Vermont Center for Ecostudies, a non-profit scientific organization, the team captured and tagged 40 birds at the Luther Marsh and in the Belwood Lake area. The geolocators track migration patterns of the birds on their 22,000-kilometre trek from Ontario to several countries in South America, including Argentina, where they stay in the winter. The 35-gram bird has been known to travel up to 1,800 kilometers a day during migration.