By Elizabeth Laubach
A sharp turn onto a gravel road signifies entrance to the Iain Nicholson Audubon Center at Rowe Sanctuary. My first up-close view of the Sandhill Cranes was within their modern-day feeding ground- cornfield.
The Platte River was once a wide, shallow river surrounded by wetland marshes and interspersed with low-lying sandbars where the cranes fed on tall grasses. Conventional agriculture in Nebraska’s dry soil and atmosphere involves irrigation, based on water that is pulled from the river and from the Ogallala Aquifer. This practice sucks moisture out of wetland habitat where houses and row crops haven’t taken over.
Luckily, the cranes like to eat the corn waste left in the fields, especially the insect called corn borer that infects corn and is a huge pest to farmers The cranes and farmers have a symbiotic relationship during the cranes’ stay. Most of the cranes head north by April, but volunteers at the Iain Nicholson Audubon Center at Rowe Sanctuary said some have been known to stay into planting season. After newly planted seeds sprout, late-departing cranes pluck the new sprouts out of the ground. This is a seemingly successful example of nature adapting to modern society.
Another form of cranes’ adaptation to modern human existence is their first-ever recorded winter stay in Nebraska. Prairie Fire magazine and Iain Nicholson Audubon Center at Rowe Sanctuary volunteers said about 2,000 Sandhill Cranes did not continue south to Texas, Mexico or Arizona, which are their usual wintering locales. Instead they stayed in Nebraska.
Usually, the cranes will only pass by overhead or stay for a short night before they continue south. An article in the March issue of local progressive Prairie Fire magazine, titled “Sandhill Crane Congregation Makes a Prolonged Visit,” speculates severe droughts in Texas could have caused the cranes to stay in Nebraska. The author went as far to question whether the cranes had flown to Texas, then turned back after realizing no water was available.
Cranes are known to travel extremely far distances without stopping because of their penchant to ride the high-altitude winds, so that the least amount of effort is expended in flight. The reason for the cranes’ overwintering in Nebraska was the lack of these winds to drive them down to Texas, said Catherine Hall, a volunteer at Iain Nicholson Audubon Center at Rowe Sanctuary.
Dave Brandt, a wildlife researcher studying cranes among other wildlife in Texas, interviewed by the author of the Prairie Fire article, agrees. He says the cranes still in Nebraska were “just enjoying the nice weather.” The author states biologists in area along the Platte River where the cranes migrate were also attributing the mild winter as a reason why the cranes stayed.
The National Oceanic and Atmospheric Administration reported that the 2011-2012 winter was the fourth warmest on record and drier than average for the lower 48 states. If this trend continues, will the Sandhill Cranes continue to overwinter in Nebraska? Only time will tell.