Birds of Millborn Farm

Millborn Farm’s fields, pond edges, wetlands, and forest borders support a changing cast of birds throughout the year. Some stop here briefly during migration. Others nest, feed, and raise their young across the property’s varied habitats.

Use this trail to pause, look, and listen. Bird activity changes with the seasons, the weather, and even the time of day. Bring binoculars if you have them, and move slowly, sometimes the best birding happens when you stop walking and simply watch.

Wetlands and Waterways

While traveling along the water’s edge, you may see a carefully woven duck nest tucked into the grasses near South End Pond. Many waterfowl construct inconspicuous nests of nearby plants and feathers, choosing secluded spots within the brush.

Waterfowl are web-footed migratory birds that live in freshwater habitats. Ponds are like an all-inclusive hotel for these birds; they provide lodging, foraging, and nesting services. Frequent visitors of this pond are ducks, which can be split into dabblers and divers. Dabblers feed at the surface of the water, dunking their heads to look for aquatic plants, algae, insects, and small crustaceans. If you see a few waterfowl tail feathers sticking out of the water, you’re looking at dabbling ducks! Mallards, American Black Ducks, and Northern Shovelers can be seen dunking their bills into South End Pond. Ducks can be found year-round in Massachusetts, but species like the Wood Duck arrive for the breeding season in February and depart late-summer.

Divers fully submerge to feed and can be found more commonly in marine species. You may see Common Mergansers and Hooded Mergansers dive below the water and emerge up to two minutes later with a mollusc, small fish, insect, or plant in tow. All ducks assist the pond’s health by dispersing seeds, controlled pests, and contributing to the nutrient cycle.

In peak health, a pond provides several ecosystem services for local fauna. They stabilize the surrounding environment by purifying water, mitigating floods, and storing carbon. Aquatic plants absorb excess nutrients from the water, preventing excess contamination and keeping the ecosystem clean for foraging creatures. When a pond is inundated with excess nutrients, such as nitrogen and phosphorus, it experiences eutrophication. Eutrophication causes huge algal blooms, which massively deplete a pond’s oxygen content as they decompose. This leads to “dead zones,” which lack oxygen and cannot sustain aquatic life.

Seasonal spotlights include:

Grasslands

Strolling along the trails, you’re likely to hear songbirds twittering and chatting across the fields. For birds, the grassland is a bustling community hub which offers reliable resources to its visitors.

Bobolinks are one such species, finding a haven in the healthy tall grasses and broad-leaved plants. These flamboyant birds travel up to 12,500 miles from South America to breed as far north as southern Canada. Once they’ve arrived, bobolinks get to work on their nests in open grasslands, weaving a new home directly into the soil beneath dense vegetation. Occasionally, a Bobolinks nest is overtaken by another species. Brood parasites, such as Brown-Headed Cowbirds, tend to lay their eggs in other species’ nests. Once a bobolink has completed its breeding season, it will move on to the freshwater wetland to molt before migrating once again. Unfortunately, bobolink populations have declined due to modern agricultural practices.

Over the winter, the grassland fills with snow and acts as a sponge which holds onto snowmelt and releases it back into creeks and streams throughout the following months. Rising groundwater levels and streams inundate meadows and bring nutrients that sustain the landscape, acting as a natural reservoir to reduce regional flooding. During the growing season, this water saturation nurtures plants through critical reproductive stages, maintaining life critical to Millborn Farm’s avian biodiversity. Eastern Meadowlarks enjoy a diet of caterpillars and crickets, while hardier species like Wild Turkeys forage for any plant or animal life they can see. Deep-rooted plants improve soil structure and health, preventing soil erosion, enhancing water filtration, and promoting safe nesting sites. The rich collection of terrestrial and aerial species here owes their success to the meadow’s health.

Seasonal spotlights include:

Forest Edge

The edge habitat is a dynamic zone, abundant with species interactions. Edge habitats are spaces of constant change, serving as transitional spaces for environmental conditions and species alike.

As you walk down the path, you may hear the gliding sound of wings and smooth chirps – it’s probably a Tree Swallow! These migratory birds winter in Central America and travel north for the breeding season in the spring and fall. Transitional habitats close to freshwater, such as meadow edges and wetland boundaries, are the passerines’ spot of choice. These ecotones, or transitional habitats between ecosystems, provide a variety of forage and nesting cavities for the breeding season. Once established, Tree Swallows become quite outspoken, spending much of the breeding season lingering around their nest to ward off predators. If you get too close to a nest, they may swoop right up next to you, warning you to back up a bit.

You may hear a range of other birds in this environment. Songbirds such as Blue Jays, Savannah Sparrows, and Eastern Bluebirds also call this ecotone their home. The diversity of options for food, shelter, and nesting sites make the edge habitat an attractive spot for songbirds. It may be a risky hangout spot, however; predators also tend to enjoy the richness of this habitat. Birds of prey, such as Merlins, use an assortment of hunting strategies to catch songbirds, including surprise attacks and paired hunting with a mate. These falcons are extraordinary flyers and incredibly territorial, often flushing out large flocks of songbirds.

Invasive plants tend to establish a foothold in these environments due to its constantly changing status and the prevalence of songbird populations. Songbirds enjoy perching on the stone walls and lined trees, dropping seeds along the field edges. Many of these seeds originate from invasive plants and quickly establish populations.

Seasonal spotlights include:

Nest Boxes

If you stumble upon a mounted birdhouse on any of our trails, you’ve found an Eastern Bluebird nestbox! Nest boxes are conservation features that establish nesting sites for a range of species depending on environmental conditions and conservation needs. The usage of the box depends on where it is located, how big it is, and the size of the boxes’ entrance hole.

Human activity has greatly reduced the amount of nesting sites available to birds. Urban development has crowded out many local grasslands, which bluebirds prefer to nest by. Populations have been decreasing with the progress of development, and nestboxes compensate for this lack of adequate nesting sites.

Boxes are observed regularly by dedicated volunteers. Nest box’s locations can be input on the Cornell Lab application “NestWatch,” a platform that tracks nesting and egg incubation outcomes. Volunteers monitor the boxes once per week, checking for the type of nesting bird, and progression of the nest, and whether eggs have been laid.

Although these boxes are intended for Eastern Bluebirds, other species can make nesting attempts, but this can be beneficial! Here at Millborn Farm, you may notice that nest boxes are placed in pairs of two. Generally, bluebirds prefer to nest next to a different species rather than another mated bluebird pair. Tree Swallows will often nest in these adjacent boxes, which improves that likelihood of bluebird nesting in nearby boxes. If you find yourself with swallows diving every which way around you, it is likely that a pair of bluebirds are nesting in the box a few feet away. House Wrens are also proven rivals, tending to discard bluebird eggs and claim an occupied nest for themselves. If you come upon a nestbox with a mess of twigs poking out, you are likely looking at a House Wren nest.

Though it is tempting to peek inside, depending on the time of day, you may be interrupting a bird’s family time. Birds tend to lay eggs early in the morning, and an unexpected disturbance may cause the bird to abandon the nest site. Even if it is past early morning, these are the birds’ homes. We’d prefer if people didn’t peek through our curtains from the lawn, and bluebirds prefer the same!

Every corner of Millborn Farm offers a unique glimpse into the intricate relationships between birds and the landscapes they inhabit. Keep learning more by exploring avian informational sites like eBird and Merlin or getting involved with avian conservation work at the Trustees.