Raptors at Risk
Sharp-shinned Hawk Image by Dave Brandes
We identify species on the Raptors at Risk list by evaluating 10- and 20-year migration trend summary indices (TSI), as well as winter trends based on Christmas Bird Count data. These species have the highest amount of declining migration counts over the last two decades and also show no concurrent winter increases.
Raptors at Risk (red and orange). We identify high-risk (red) species as those with migration TSI’s less than or equal to -0.7 during any time period (10-yr, 20-yr, or both) and that also show a negative winter TSI based on the most recently available Christmas Bird Count trends. Similarly, we identify moderate-risk ( orange) species as those with migration TSI’s less than or equal to -0.5, and that also show negative winter trends.
Note: Species with trend data from less than five sites continent-wide, e.g. Prairie Falcon, were not categorized due to insufficient trend data relative to the species distribution.
