On Saturday, 4/1/23, we counted an estimated 261,300 +/- 28,500 Sandhill Cranes in the Central Platte River Valley. It does appear we are on the decline of Sandhill Cranes in the area. However, in biology numbers only tell a portion of the story. Our week 6 count was lower than expected, especially in the western segments of the river (Wood River to Overton). On March 26th, we attempted a flight and had to cut our survey short due to unsafe conditions and low visibility. Ironically, despite the lower visibility in the air, we were able to see cranes in fields much further than our usual sampling distance because they contrasted with a fresh layer of snow. The majority of Sandhill Cranes we saw were actually not roosting in the river but were roosting in the fields and meadows up to a few miles away from the river. We saw similar roosting behavior on Saturday before our survey began leading us to believe that this unique behavior wasn’t just a one-time thing and a portion of the cranes probably have been doing this for a while. This most likely explains why our counts in the western segments of the river have not been following similar trends from past years and have been much lower than expected, whereas counts in the east are more on par for each week.
We do not know the exact reasons for this divergence from normal roosting behavior but it could be a result of erratic river flows, lower food availability, increase disturbance on the river (predators, air traffic etc.), or something entirely different.