I suspect that most folks that enjoy birding would like to make the trek to Texas’ High Island to witness the spring songbird migration. If you catch conditions just right, in a single day, you can get up close and personal to 30 species of warblers and literally scores of vireos tanagers and other birds. While this small island is the one of the very best places to see spring migrations, if you have the right habitat, you can see a kaleidoscope of songbirds from March into May pass through your own yard.
As migratory songbirds move northward, they make a number of stops before they reach their breeding grounds. These bits of critical habitat are referred to as stopover areas. Songbirds rest and refuel at these locations. Backyards offering the birds the proper food, water, and cover can serve as stopover sites.
The vast majority of migratory songbirds rarely visit feeders stocked with seeds and suet. However, can you attract them if you offer them the foods that will help fuel their spring migration flights. By far, the most important foods eaten by spring migrants are insects. However, the bulk of the insects consumed by the birds are the larvae of moths and butterflies (commonly referred to as caterpillars).
Most of these caterpillars feed on tree leaves. Therefore, if one or more of the trees that serve as hosts for moths and butterflies is growing in your yard, the better are your chances of attracting spring migrants.
When it comes to hosting moths and butterflies not all trees are created equal. The worst trees are introduced ornamentals. Some of these trees do not host any moths and butterflies. Studies have shown ornamentals produce 35 times less caterpillar biomass than native trees.
Here is a short list of some of the native trees that host the most species of moths and butterflies. The numbers of species of moths and butterflies that each tree hosts are found in parentheses. This list was developed by Dr. Doug Tallamy.
In Georgia, oaks (557) serve as host plants for more butterflies and moths than any other group of trees. Other important hosts to lepidopterans are cherries (456), willows (455), birches (411), poplars (367) crabapples (308), maples (297), alders (255), hickories (235), elms (215), pines (201), hawthorns (168), beeches (127), dogwoods (118), and sweetgum (35).
Should you find that none of these trees are in your yard, if you want to have your yard serve as a spring songbird stopover site, consider planting one or more trees found on this list. The small investment in time and labor this requires will pay huge dividends for decades to come.
If you already have one or more of the caterpillar producers growing in your yard, from now into May, periodically scan the tree foliage for migrants. How long the migrants stay is largely dependent on the amount of food they find. If your trees don’t harbor many caterpillars, migrants might stay and feed for only a day. Conversely, if caterpillars are abundant, migrants may linger for three or more days before moving on.
If you are lucky, one morning you may walk outside and see your trees alive with a dozen or more warblers gleaning insects for your trees’ foliage. While you might see far more species at High Island, the fact that you spotted these birds in your yard will make the experience extra special.