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Purple Martin

Male has iridescent purplish blue body with dark brown wings
Female has brown wings and back, and light underparts, but ...
... may acquire a purplish blue sheen with age
Male in flight
Female in flight
Broad base of beak helps to firmly grasp ...
... even large insects caught in flight
Female chooses male based on quality of nest site he occupies
Acceptable nesting cavities include hollowed out gourds ...
... rectangular bird houses, molded plastic globes ...
... a high rise of gourds ...
... or even the ultimate 70-feet-tall condo with 562 apartments
Clutch consists of 3-6 eggs
Newly hatched chicks are totally helpless
Wide base of beak obvious in nestlings
Parents kept busy hunting prey for voracious chicks
Fledglings develp dimorphic adult plumage within two yeaars
Martins roost together shortly after breeding but nothing like ...
... the winter roosts of thousands that form in Brazil

Available records for Salter Grove from 2002 through 2023 document that the Purple Martin was only first reported in late July 2021.  It was observed twice subsequently during August 2022.  Since this largest of all North American swallow feeds higher off the ground than other swallow species, scan for them where expansive overhead views are possible such as on Audubon Hill, along the causeway or the marshy shoreline of South Cove.

Historically, it nested in old woodpecker holes throughout temperate America along rivers or the edges of forests and woodland.  However, since the 20th century, eastern populations have relied almost entirely on artificial nesting structures.  Its scarcity at Salter Grove suggests that there are no martin houses nearby. 

As early as the 1700's Native Americans suspended hollowed-out gourds, and early settlers installed nest boxes high above the ground to attract Purple Martins to their respective settlements.  These units of above ground real estate attracted seasonally reliable tenants since martins return agin and again to nest sites where they have experienced reproductive success.  The human landlords counted on their feathered tenants to eat up agricultural insect pests as well as to mob and repel raptors that come to prey on poultry.

Since then, studies have shown that the Purple Martin is a year-round aerial insectivore that feeds on a wide variety of flying insect, such as bees, beetles, butterflies, cicadas, crickets, damselflies, dragonflies, flies, moths, wasps, and winged ants among many others.  A study published in 2015 indicates that they will feed readily on fire ants, which may offer a biological solution for controlling this noxious and invasive pest.

For a time, it was widely believed that a single Purple Martin consumed 2,000 mosquitos per day, prompting many home owners to set up martin houses in their yard.  Unfortunately, a study published in 1968 revealed that it actually does not eat very many mosquitoes, but the long-held belief nonetheless has sold many martin houses.

Its readiness to use artificial nest sites saved the Purple Martin from a population crash during the 20th century.  It was displaced from nest sites by the more aggressive European Starling and House Sparrow, two introduced species that also breed in tree cavities. 

In the not too distant future, its numbers may decline again since current martin house enthusiasts average at least 50 years old and younger people have not shown an equivalent interest in maintaining martin houses.

Purple Martins spend six months of the year in South America, primarily Brazil, where thousands roost together nightly on power lines in urban areas.  Their yearly arrival in the southern hemisphere is not always welcomed.  They are considered a health hazard due to their nightly deposit of excrement.  Attempts to disrupt or relocate roosting martins will likely affect breeding populations as well.