Here in South Jersey, there are several bird-related phenomena that feature the simple abundance of a species as they migrate through the area. Think shorebirds on the Delaware Bayshore in springtime, as they fuel up for their flights north to their breeding grounds. Or a late September day with northwest winds as falcons and other birds of prey stream over the Hawkwatch platform by the hundreds at Cape May Point State Park. Or farm fields white with thousands of snow geese in Salem County in the wintertime.
In late summer, it’s Purple Martins that put on a show as they gather every evening on the banks of the Maurice River in Cumberland County to roost together overnight. There is safety in numbers and the birds tend to select a slightly different location every year. In the first weeks of August, the numbers arriving each night grow and grow into the hundreds of thousands. Toward the end of the month, when conditions are just right, the Purple Martins will depart one morning, nearly all of them at once, for the next leg of their journey to South America for the winter.
While Purple Martins can be found on the west coast of the U.S., their populations are much larger east of the Rockies and they are entirely dependent on human intervention in the form of nest boxes. They prefer to nest communally, and you can see Purple Martin apartment complexes high atop poles all over our area. Cape May Point State Park is home to a successful colony, which is carefully monitored by park staff and volunteers.
They are North America’s largest swallow. Only adult males are uniformly dark; nearly black with a blue purple iridescence. Female and Immature birds are brown and have buffy breasts and undersides.
Pete Dunne, birder extraordinaire and professional writer, first noted the visual thrill of the congregation of birds in the mid-nineties. Soon after, people would line the sides of the bridge to catch a glimpse. Enterprising folks even rented a flatbed to park along the river, to provide elevation for better viewing.
But the Maurice is a winding river, and as the roost site shifted each year, it became apparent that the best views would be from a boat, preferably one that could provide some elevation. Citizens United to Protect the Maurice River and Its Tributaries (www.cumauriceriver.org), a local non-profit conservation organization, runs charters called Purple Martin Spectacular Cruises, which take a leisurely ride up the river to arrive at the roost site at dusk.
There is plenty to see along the way, especially Osprey platforms and maybe even Bald Eagles. Naturalists from CU Maurice River and Cape May Bird Observatory are onboard to answer questions and point out other species. As the sun sets, however, the anticipation grows. “Where are they?” “Maybe they’re not here.” “Maybe they’re farther upriver.” “Maybe they left last night!”
Then, one by one, two by two, three or four more and suddenly, they’re everywhere. It’s raining Purple Martins with some other swallows joining the flock. They swoop, swarm and funnel down into the reeds. And then back up again. And then back down again, in what Pete Dunne called, “a living tornado” of birds. Eventually, they have settled down for good and that night’s show is over. It is truly a sight to behold.
Although it looks like the CU Maurice River charters are sold out already for this year, you can certainly put in your own boat, canoe or kayak. Depending on where the birds roost this year, you might even have some luck from the quaint Waterfront Park on the edge of the river in historic Mauricetown. You can learn more about Purple Martins on the Purple Martin Conservation Association website, www.purplemartin.org.
