BEHAVIOR OF PEREGRINES IN WINTER IN SOUTH TEXAS

The movements and other behaviors of seven radio-tagged peregrine falc ons (Falco peregrinus) were determined in winter near the Laguna Madre in southern Texas in 1993 and 1994. In January and February most of t he falcons hunted in areas 20-28 km across and showed extensive overla p. Most locations of falcons we monitored were on the vast tidal flats at the margins of the Laguna or over the shallow water where numerous perches are present in an otherwise featureless habitat. One adult fe male moved a maximum of less than 8 km. Four of the falcons we instrum ented had been trapped in the area before, or remained months after th e study. We estimated a minimum density of 20 peregrines inland of the beaches of South Padre Island, or about one bird per 50 km(2). The Gu lf Coast of Texas and Mexico have several times the area of tidal flat s we observed and the region is surely a major newly discovered winter ing area for peregrines. We speculate that some peregrines may spend t heir first summer there.