The trees were coming into full leaf. The air was clear and warm without the oppressive humidity that could come with summer. And best of all, the woods were alive with birdsong and the spritely movements of wood warblers.

It was Cinco de Mayo, the fifth of May, and that meant it was time to visit Violettes Lock and see how nature celebrates this special day.

As we stepped deeper into the woods, my eye was quickly captured by the rapid action in the heavy undergrowth just to our left. A tiny bird was flitting from twig to twig, searching for insect prey.

He was a handsome blue bird, with a jet black face, neck and flanks. Many wood warblers can be a confusing mix of colors, but not this one. It was unmistakably a male black-throated blue (Setophaga caerulescens).

This blue-and-black beauty has a white square visible on its folded wing that matches the solid white breast, belly and undertail coverts which vividly contrast with its namesake colors.

He was about 5 inches long and weighed just one-third of an ounce.

Identifying females is not so easy. They are a rather ordinary olive-gray overall, with slightly darker wings and tail. The underside is an unmarked yellowish white. The most distinguishing features are the long pale eyebrows and tiny white arcs below the eyes. The only thing suggesting that she is related to the male is a similar white square patch on the bended wing.

Violettes Lock is on the C&O Canal in Montgomery County, MD. This area is an especially bountiful one for spring birding. Surrounded by forest, agricultural fields and a nearby golf course, it provides ideal habitat for migrating songbirds.

Black-throated blues breed in Eastern North America, from northern Pennsylvania up into southern Canada. A number also take to the higher, cooler elevations of the Appalachian Mountains in a long, contiguous swath from Georgia to New York. Violettes Lock is just a stopover.

Typically, she will lay four eggs over four days. As she incubates them, the male will supplement her diet. When the chicks hatch, they are helpless, and both parents bring them food. They grow rapidly and fledge on unsteady wings by day 12. Often, their parents will have a second brood in midsummer.

In late March, the birds begin their spring migration. It happens quickly, and they fly through the eastern United States on a predictable schedule. Fall migration is a bit more spread out, with birds leaving their breeding territory from late August all the way into October.

Unlike most warblers, black-throated blues do not have a confusing fall molt. What you see in May is what you will see in September.

Black-throated blues eat insects, primarily Lepidoptera, from caterpillars to mature moths and butterflies. The warblers usually hunt in the thick understory of mature woodlands. For birders, this means look straight ahead, not up, when searching for them.

The species is one of the most studied of all warblers. Most of the credit goes to the remarkable Hubbard Brook Experimental Forest in New Hampshire. Ornithologists there have been studying this species for decades. These kinds of long-term research projects make extraordinary contributions to our scientific understanding of nature.

The Chesapeake Bay has its own long-term research and data projects ranging from water quality monitoring, blue crab counts, underwater vegetation surveys, and sea level rise, to name just a few. Funding for such long-term projects is always precarious, especially now with the Trump budget calling for a 90 percent cut in the Bay Program budget.

Because of such data, we know that the population of black-throated blue warblers is stable or even increasing. Today, there are more than 2 million of them.

We live in a society that values the immediate; and the excitement of catching a glimpse of a black-throated blue warbler helps to explain why.

Too often, though, we fail to appreciate the larger context of these special moments.

Because of the work of others, I know exactly when and where I can see these handsome birds. Because of years of scientific study, I know much about them. Because of the years-long conservation efforts on coffee plantations in the Caribbean, these birds have a safe winter habitat.

As the black-throated blue spirited out of view, I thought of how these few minutes of pleasure depended so much on a much longer time frame. It was a realization that seems to run counter to the short-sightedness of policy makers who would cut off support for the myriad efforts that go into such a wonderful moment.

Let’s make sure we can continue to celebrate Cinco de Mayo with our avian friends for years to come. Time to get out of the woods and into action.