It is one of the rituals of winter in Mississippi: the arrival of the first purple martins. That means spring isn’t too far off — no matter what that groundhog in Pennsylvania says or what the National Weather Service predicts for the next several days.
The president of the Purple Martin Conservation Association wrote in a recent email that someone in Sandy Hook, along the Walthall-Marion County line in the southern part of Mississippi, on Jan. 27 was the first person in the country to see some of the birds as they made their way back to the Northern Hemisphere.
The email described the person making the report as “one of many people throughout the eastern and central United States who track and report on the birds’ annual migration.” It turns out there’s a lot more to the purple martins’ story than heralding the approach of spring.
The birds are the largest type of swallow in North America. They live in the eastern United States and Canada, but every year travel up to 7,000 miles to spend the winter months in the Brazilian rain forests.
The email, from conservation association president Joe Siegrist, praised both the resilience of the birds and the loyalty of their thousands of human helpers, who maintain nests for the martins.
“Once widespread in rural America, this species, that eats billions of flying insects annually, has been disappearing at an alarming rate, experiencing a loss of one-third of its population over the last 50 years,” the email said.
“The decline seems to be the combination of a few factors: nesting habitat loss, competing invasive species, decreasing prey availability and climate change. Over the majority of the purple martins’ range, they are unable to nest naturally any longer. Human-provided nest boxes are the only thing keeping the species alive east of the Rocky Mountains.”
Wikipedia attributes the population crash to the release and spread of European starlings in North America. That “competing invasive species,” along with sparrows, battles purple martins for nesting areas, and the starlings apparently are winning the survival-of-the-fittest competition.
When it comes to smaller numbers, the martins have plenty of company. The American Bird Conservancy reported last year that some bird populations, such as the bank swallow and evening grosbeak, have fallen between 80% and 90%. And a 2019 study in the journal Science estimated that since 1970s, the bird population in the United States and Canada has declined by 29% — a loss of 3 billion birds.