Study of Plum Island waters — lots of life, no human impact

Outlined against a powder blue sky, two terns swirled in a light breeze over the waters surrounding the north side of Plum Island. The two birds were obvious. Less obvious was the abundance of life under them.

To appreciate that, all one had to do was plunge below the surface, like four scientists did, literally diving into the biologically rich waters as part of a scientific study. The dive was conducted by the New York Natural Heritage Program and sponsored by Save the Sound.

The scientists concluded five days of dives Friday, collecting samples, recording data and analyzing what they found. It was a follow-up to a 2019 dive that had scientists marveling about the diverse habitats and abundance of life they found.

“This is one of those ‘wow’ sites right here,” said diver Steve Resler, who also took part in the 2019 dive.

What makes it a “wow” site?

“The numbers and the diversity of both the fauna and the algae that we got down there,” he said. “We got thousands of anemones. We didn’t see that many back in 2019.”

What divers noticed is they didn’t see evidence of human intrusion in the nearshore waters they examined.

“I come from a background of lake diving in upstate New York, and on lakes you tend to find a lot of human impact, garbage,” diver Dave Winkler said. “Diving here, the two-diver teams, between the four of us, we have completed in a week probably at least 12 to 13 dives completely around the island, and I ask them almost every day, ‘Did you see any human impact today?’ And there’s been nothing yet of any of that. We haven’t seen any fishing lines or bottles, plastic, nothing. So, from what I’ve seen, it’s pristine from that standpoint.”

Perhaps that shouldn’t come as too great a surprise. Federally owned Plum Island is off limits to the general public. Plum Island, which covers 822 acres about one and a half miles off the eastern tip of Orient Point in Gardiners Bay, has long been shrouded in mystery. Established by the United States Department of Agriculture in 1954, it has been used by the Army and as an animal disease laboratory. As part of a plan to relocate the animal research facility to Manhattan, Kansas, the Department of Homeland Security put the three-mile-long island up for sale in 2008, but it was taken off the auction block in 2020 amid concerns about development.

“We do know that the terrestrial land of Plum Island has been mostly undisturbed since the 1950s when the Army left, and most of the laboratory activities have been in the west end,” Louise Harrison, New York natural areas coordinator for Save the Sound, said. “So, approximately 600 acres of Plum Island has been really undeveloped, untrampled for 70-plus years. That also allows wildlife and nature to return in abundance and in diversity.”

Environmentalists would like to see the rare natural ecosystem preserved, perhaps as a marine refuge or national or state park.

Little had been known about the subtidal marine habitats and benthic species surrounding the island. Because the area supports a diversity of at-risk species, naturalists consider it to be of ecological importance and regard Plum Island’s waters as a fascinating living laboratory.

In 2019, a team of divers and marine scientists found gray seals, communities of sponges, bryozoans and tube worms covering immense boulder fields, coral, anemones, eelgrass meadows, blue mussels, algae and sugar kelp among other life forms.

On this week’s dives, ranging in depths of 30 to 10 feet, scientists swam between massive stone boulders, some up to 20 to 25 feet in diameter. They said they encountered life seemingly everywhere.

“It’s not surprising, but everything that’s available for space is pretty much filled with life, whether it’s animal life or plant life,” diver Dan Marelli said. “Then we get into sand flats and we go a little bit deeper and it’s muddy sand. Folks consider that stuff to be lifeless, but there’s actually a lot of life down there below the surface layer.”

Any surprises?

“I wouldn’t say too many surprises, but I say that with also [noting] we haven’t gone through all the samples yet because we’re getting so many bags coming up every day,” Meaghan McCormack, a NYNHP marine zoologist, said. “We haven’t identified every species that came up yet.”

As for underwater visibility, Mr. Resler said: “We can [see objects] when we’re within, say, five or six feet of things it comes out pretty clear, but there’s a very strong current. You see things just flying by, like they’re running down a highway, and we’re literally hanging on the rocks and whatnot, to try and stay in place.”

Capt. Mike Bady took a handful of journalists out on his charter boat, The Captain’s Table, to watch Friday’s dives. Why is this cause so dear to his heart?

“This is a very, very special place,” he said, adding: “I’ve always been environmentally conscious since I was a child. I like clean water and fresh fish to eat. I’ve been fishing since I [was] eight years old, but it really helps to sustain people, both mentally as well as physically. When we have really, really nice clean waters that are teeming with fish, it sustains the whole ecological chain, from the fish themselves right up to the human beings.”

Results of the dive will be published by the NYNHP and Save the Sound in the coming months.

A separate dive at the same location was conducted this week by Cornell Cooperative Extension of Suffolk County’s Marine Program. Two divers evaluated eelgrass beds and catalogued organisms using them, according to a Save the Sound press release.

“As we face climate change and we learn our dependencies on the natural world and our vulnerabilities, we have to keep in mind how we share this planet with so many other organisms, so many other creatures, plants and animals,” Ms. Harrison said. “Everything we can learn about them is going to help us live together more compatibly and preserve the life that we have and for the rest of the planet.”