Oak Lake Field Station conducts spring bird counts during the second or third week of May. These counts have been made since 1995, yielding over 10 years of bird occurrence data. Counts are always made along the same route and by a group of experienced birders using visual and audible cues to identify bird species along the route (Presence/Absence). Spring counts generally start at 8 a.m. and are completed before noon on the day of the count.