The next four weeks are heaven for birders. The spring migration is building now and will be petering out by the end of May. The birds are dressed in their breeding finery and the males (and some females) are in full, glorious song. The spring migration is more compressed than the fall when the urgent need to find a mate and nest is over.

Whose spirit is not lifted by the spring migration?

Between 1994 and 2017, I coordinated a citizen-science project to track the arrival of our migratory breeding birds. I developed a web tool that allows you to see the arrival data for over 100 species of our breeding birds that spend their winters elsewhere. If you want to know when to expect to see the first ruby-throated hummingbirds or scarlet tanager or chestnut-sided warbler, point your browser to: hobbes.colby.edu/arrival/

In my last column in anticipation of Earth Day, I wrote about actions we can do as individuals to help nature and birds in particular. One suggestion was to convert some of your lawn or other open space to more bird-friendly plant habitat.

One reader wrote to encourage the planting of native plant species. A very good suggestion. Caterpillars of some butterflies and moths are specialized on particular species of plants. A study by the New England Wild Flower Society found that over 30% of the plant species in New England are introduced. Giving our native plants a boost is commendable.

Plant habitat can fill three needs of birds – food, shelter and nesting sites. If you are interested in making your property more welcoming to birds, keep these three requirements in mind.

As for the food requirement, most of our birds have fairly broad diets. Warblers are equally happy to glean caterpillars from birches, poplars or maples, for instance. Some trees have fruits or seeds that are favored by certain birds.  The common redpolls that came into Maine this winter were searching for birch seeds. Blue jays are fond of beechnuts and acorns.

The flowers and fruits of elms are attractive to many birds, particularly pine siskins and other finches. A number of insects occur on elms, which attract warblers and vireos. Baltimore orioles often use elms for their distinctive hanging nests.

I recommend having some coniferous trees in a bird-friendly yard. Conifers provide effective year-round shelter, as well as food for a number of birds.  You can’t go wrong with the Maine state tree, the white pine, although balsam fir and eastern hemlocks are also fine trees and provide cover for birds.

Fruit-eating birds can be attracted to a number of trees and shrubs that keep their fruits through the winter. Mountain ash is a beautiful native tree with colorful red berries, which attract cedar and bohemian waxwings. Ruffed grouse and waxwings also like the colorful red berries of highbush cranberry. Pine grosbeaks like crab apples and other apples in the winter. When American robins return in the spring in force, they frequently can be found feeding on the fruits of ornamental bushes.

The flowers of apple trees are magnets for Baltimore orioles in the spring and early summer.

Hummingbirds are easy to attract. One of our favorites is bee balm, the long, tubular flowers are tailor-made for a hummingbird’s long bill and tongue. The nectar from tubular flowers generally is hard for insects to reach. All the more food for hummingbirds.

Another great addition for hummingbirds and butterflies is buddleia, the butterfly bush. Maine winters can be challenging for this bush, but what a magnet it is for nectar-feeders of all kinds in the summer. I would think buddleia would do well from Portland south in Maine.

Other flowers that are attractive to hummingbirds include azaleas, digitalis (foxgloves), coral bells, day lilies, honeysuckles, phlox, scarlet runner beans and, one of my favorites, hollyhocks.

Herb Wilson taught ornithology and other biology courses at Colby College. He welcomes reader comments and questions at whwilson@colby.edu