Drive out to Hellcat any evening this week around sunset and you'll find birders standing shoulder to shoulder at the dike, cameras pointed not at the sky's edges but straight down into the reeds. Nobody's scanning for a kettle of hawks riding a thermal. They're waiting for the swallows to come home.
On August 21, a Brookline Bird Club outing logged an estimate of roughly 230,000 Tree Swallows pouring into the reed beds at Hellcat Wildlife Observation Area, with another 15,000 Barn Swallows swirling in alongside them. Numbers on this scale are always estimates, birders count in waves and multiply, but even generously rounded down, that's a bird density most people will never see anywhere else in New England. The same walk turned up a Solitary Sandpiper working the mud on the north side of the dike, two Yellow-crowned Night Herons standing still in the marsh grass, and 17 Eastern Whip-poor-wills calling from the Hellcat parking lot as the group packed up to leave. That's one evening, one dike, one small stretch of Plum Island Turnpike.
Why Everyone's Looking in the Wrong Direction
If you moved here expecting fall to bring hawks, you're not wrong to think that, you're just thinking about the wrong season for this particular spot. The official Plum Island Hawk Watch, run from Parking Lot #1 near the refuge restrooms and visitor station, only operates from the last week of March through May 10. It's a spring count, plain and simple, built around American Kestrels, Sharp-shinned Hawks, Northern Harriers, and Merlins riding southwest winds north along the coast before the leaves are even fully out. Volunteers there tally something like 1,100 hawks across those six spring weeks. Come September, that platform sits empty. The wind patterns that push raptors past Plum Island in April simply don't set up the same way in fall, and most serious hawk-watchers looking for big fall flights head inland instead.
So the fall spectacle here had to be something else, and it is. It's swallows staging for the long flight to the Caribbean and beyond, shorebirds working the mudflats on falling tides, and a wave of warblers moving through the woods behind Hellcat that most visitors walk right past because they're looking at open water instead of the tree line.
What's Actually Filling the Sky Right Now
The salt pannes along the refuge road's west side are worth a slow drive-by through September. That stretch is one of the better places on the island to catch a real variety of shorebirds during the July-through-September push south, and egrets and herons stick around there from mid-April clear into October. Hellcat's woodlands do their own version of the same thing, drawing in warblers and other songbirds during both spring and fall passage, feeding on the last insect hatches before the real cold sets in.
The swallow roost is the loudest version of all this. Tree Swallows gather over the marsh in the last hour of daylight, drop into the reeds in dense, shifting clouds, and hold there overnight before moving on, sometimes replaced by an entirely new wave the following evening. It's a phenomenon tied to timing more than any fixed date. Some nights it's a few thousand birds. Other nights, apparently, it's a couple hundred thousand.
A few other threads are running in parallel right now:
- Piping Plovers, which closed off long stretches of Plum Island Beach from spring through midsummer, have mostly cleared out by September, reopening sand that's been off limits for months.
- The refuge's osprey platforms, six of them now monitored across the property after two new ones went up this nesting season, are emptying out as pairs start heading toward wintering grounds farther south.
- The refuge's daily entry is five dollars per car, waived with a federal Duck Stamp, a Parker River annual pass, or a Golden Age passport, worth knowing if you're planning more than one trip out this fall.
Who's Been Keeping Score Since 1998
None of this is new information to the people who track it professionally. Joppa Flats Education Center, which sits right at the refuge entrance overlooking the Merrimack River, has run a Bird Banding Station on Plum Island since May 1998 in partnership with the U.S. Fish and Wildlife Service. In that time, staff and volunteers there have banded and released more than 36,000 birds, feeding a long-running database that researchers use to study how specific species relate to specific habitat types on the island. That's nearly three decades of data built one bird at a time, and it's part of why scientists take Plum Island seriously as a stopover point rather than just a scenic beach town with a good marsh view.
If you'd rather learn from a person than a database, Newburyport Birders runs guided walks around town and out on the refuge, led by a Newburyport resident who's been birding for more than thirty years and built her business around teaching other people to actually see what's in front of them. Joppa Flats also runs a standing Wednesday Morning Birding walk through Newburyport and the surrounding area for anyone who wants a low-pressure way to start paying attention to what's moving through this time of year.
The Ospreys Are Already Leaving
There's something almost orderly about how this all overlaps. The osprey platforms that were full of activity all summer are thinning out. The plovers that closed the beach are gone. The hawk watch platform that drew crowds in April has been quiet for months. And into that space, right on schedule, comes a roost of swallows so dense that birders drive out at dusk just to watch a wall of them fold into the reeds.
If you've lived here long enough to have an opinion about which season is best on Plum Island, this is worth reconsidering. Spring gets the hawks and the headlines. But late August into September, out at Hellcat, with the light going gold and the swallows starting to circle, might be the better show. It's just quieter, and it happens closer to the ground.
If you're already the kind of neighbor who knows the tide charts and the name of the person leading the Wednesday walk, you're the reason this place works the way it does. And if a friend ever asks you what it's actually like to live out here, past the beach and the summer traffic, this is the kind of answer worth giving them.
For more on what makes this stretch of coast worth paying attention to, or if you're weighing a move to Plum Island yourself and want a local's read on it, reach out to Kevin Fruh. He's been watching this island longer than most, and not just for the birds.
