Spring. Sandhill cranes, robins, grackles, and now vultures. They are all returning from their winter retreat. It is called migration, or the regular back and forth movement of animals between two locations.
March is the month of the spring migration. Actually the sandhill cranes arrived in February. Almost like clockwork the first small flocks show up at the Rowe Sanctuary near Gibbon on Valentine’s Day. How do cranes know it is Valentine’s Day? They don’t and they don’t care. They instinctively know the length of the day, which is called the photoperiod, and react to it by heading north when each day contains a certain number of hours of light.
As March progressed more and more sandhill cranes, along with white-fronted geese, Canada geese, snow geese, and a myriad of ducks crowded the skies and corn fields of central Nebraska. We are not their destination; we are a stop-over location where they can rest, feed, and get ready for a final push to their nesting grounds. The timing is important. They have to get to the nesting grounds as soon as it is suitable for them. If they get there too early everything is still frozen. Too late and they won’t have the “kids” completely raised and ready for the fall migration. Sandhill cranes do nest in Nebraska, just not very many. Nests have been documented in the Rainwater Basin and elsewhere, but they are somewhat rare.
Birds aren’t the only things that migrate. Fish migrate, for example, the now extirpated McConaughy rainbow trout would migrate up the small side streams along the Lake and North Platte River. After spawning the fish would return to Lake McConaughy. The young would hatch and flow down the stream to the lake. If they survived for two or three years it was their turn to migrate up the same stream to the same spawning location. Over time many of the small springs dried up. In addition different predatory species stocked in the Lake to enhance the fishery were hard on the young trout so that now, unfortunately, though named for the Lake, there are no more McConaughy rainbow trout in Lake McConaughy.
Insects also migrate. The Monarch butterfly travels 5,000 miles in its migration. No single butterfly makes it from one end to the other. It takes several generations for it to get from Mexico to Canada and back. The Monarchs leave the wintering grounds in mid-March and soon they will be showing up here in Nebraska. As an aside, the movement of the Monarch pales beside the wandering glider, a dragonfly that annually flies back and forth across the Indian Ocean from India to Uganda.
However, the reason I started to write about migration is the return of the turkey vultures to Gothenburg. During the winter the birds head south as far as Mexico. Come March they start heading north. Bisbee, Arizona has a festival on the second weekend of March each year to celebrate their return. In Hinckley, Ohio the birds almost always return on March 15 and since 1957 the town of Hinckley has celebrated this event with “Buzzard Day” in which not only birds, but also thousands of people show up.
Buzzards also return to Gothenburg at roughly the same time each year. According to my records the earliest I’ve seen them is March 23, and the latest first sighting is March 29. The average date for my first sightings of vultures here in Gothenburg is March 25. This year it was Saturday, March 27. All last week I watched the sky each night to see if they were back, and then on Saturday morning I stepped out into the yard and there, roosting in my big cottonwood tree, were five turkey buzzards. Spring is most definitely here!