Nature Notes – First bluebirds have returned to the area

By Jim Gilbert

A few eastern bluebirds attempt to winter-over in Minnesota but nearly all of them spend the cold months in states south of us, returning in greatest numbers between mid-March and mid-April.
This year it was late March when the first migrants were spotted in the area. Their habitat includes farmlands, orchards, roadsides and open woodlands. They nest in natural tree cavities, old woodpecker holes, wooden fence posts, and the nest boxes we put out for them. Insects made up the main part of their diet, but they also eat fruits and seeds during the months when insects are scarce.
A female eastern bluebird is a fainter version of the male. He has a sky-blue head, back and tail, a rusty-red throat and breast, and white belly.
This seven-inch bird is a favorite of many people, but 50 to 70 years ago was nearly eliminated in Minnesota due to the increased use of insecticides, the dwindling number of wooden fenceposts, and a competition for nest sites from two introduced species – the house sparrow and the European starling.
Numerous individuals and organizations have helped bluebirds make a remarkable comeback in the last 40 years by establishing and maintaining trails of nesting boxes.

What’s happening outdoors now?
With well over two feet of ice covering area lakes, it seems unbelievable that in 2012 the ice-out date for both Hydes Lake and Swede Lake was March 17, and Lake Waconia, Pierson Lake and Goose Lake on March 18. All these are Carver County Lakes. The medium ice-out for Lake Waconia is April 10, with data going back to 1940. The medium ice-out date for Lake Minnetonka is April 13, with records going back to 1855.
These are busy days for Don and Mary Somers at Somerskogen, a sugarbush in Minnetrista, and for Clark Machtemes and his family at East Bay Sugarbush located near the northeast side of Lake Waconia.
Maple sap flow is triggered by thawing days following freezing nights. In southern Minnesota the best flows tend to come between March and the first few days of April, at which point leaf buds swell and sap becomes bitter.
This year will be later because of colder spring temperatures, lingering deep snow in the forests, and frost in the ground. We are hoping for good to excellent sap runs the first two weeks of April.
Each year, 312 bird species are regularly seen in Minnesota, and most of these are migrants.
Migrating American robins first returned to Waconia on March 19 this year; they were flighty and noisy unlike the calmer, quiet wintering-over robins.
A few other birds that have arrived in this area lately include: Canada geese, great blue herons, sandhill cranes, and red-winged blackbirds.

On March 27 a year ago
We had a sunny day with a low temperature of 23 degrees and a high of 43 degrees F, our warmest temperature in 105 days going back to Dec. 12. Ice was thick on area lakes, and six inches of snow covered the landscape, but the first great blue herons, and migrating American robins and Canada geese were back.