Date of this Version
Johnsgard, "Comments on Nebraska's Falconiform and Stringiform Bird Fauna," from Nebraska Bird Review (June 2001) 69(2).
Owing to a lack of long-term survey data, determining whether Nebraska's raptor numbers are stable, increasing, or decreasing is difficult. Unlike our relatively well-monitored gamebirds, no regular surveys have been performed, and raptors barely register on the state's Breeding Bird Surveys or Christmas Bird Counts, owing to their relative rarity. However, a few data-points of interest do exist, which might be worth summarizing.
In one of the first multi-year surveys of Sandhills avifauna, H. Elliott McClure (1966) summarized raptor abundance data based on three years of study in the Nebraska Sandhills (1 941-1 944). During that period, he typically drove from a ranch near Ord to Valentine National Wildlife Refuge each Thursday, returning on Friday or Saturday, and driving 350 miles round trip. On these trips he tallied all the larger birds seen, including raptors. He summarized these data as birds seen per day, but they have here been converted to relative percentage abundance of species, to facilitate comparisons (Table 1).
In 1959 John and Ann Mathisen published a population study of diurnal raptors in the Panhandle, based on one year (1957) of roadside surveys. They traveled 17,807 miles over a year-long period, making surveys on 1 28 days that included counts made every month, from as few as 6 to as many as 15 days per month. Their findings provide an invaluable snapshot of the species composition and relative abundance of the Panhandle's hawks, falcons, and eagles as they existed in the 1950's. Their data are also summarized in Table 1. A somewhat similar but much more limited winter roadside survey was later made by Shupe and Collins (1983) in southeastern Nebraska.