Long Island’s natural history is getting some new chapters.
River otters appear to have doubled their range in a decade, more bald eagle pairs are setting up nests each year, and scientists are researching a great white shark nursery found off the South Shore.
Let’s start on land.
“Long Island is being recolonized,” wildlife biologist Mike Bottini said about river otters during the Long Island Natural History conference held last week at Brookhaven National Laboratory in Upton.
River otters, members of the weasel family, were once common on Long Island, but their numbers were drastically reduced nationally and here because of fur trappers. By the 1800s they were considered locally extinct, Bottini said.
Still, sporadic sightings occurred over time, and the state Department of Environmental Conservation says that, in fact, the presence of river otters has been documented on Long Island for more than 15 years. But no dedicated surveys were launched until 2008.
That year, Bottini surveyed 164 sites in Nassau and Suffolk counties and found otter markers at 27 locations, mostly from Bayville to Kings Park and a small pocket near Greenport.
This year, Bottini’s Otter Field Survey team has spotted evidence of otters stretching from Bayville to Peconic Bay in Riverhead, and from Greenport east to Orient Point and south to inland sections of Bridgehampton. The survey is not yet complete but data thus far indicate their range has doubled in the past 10 years.
Bottini believes they could be coming over from Westchester or Connecticut, by way of Fishers Island.
“I expect to see them on the South Shore within the next couple of years,” said Bottini, a founder of the annual conference that began in 2012.
The DEC has for the past two years surveyed the region for otters and the data are being finalized. “The rough data show similar positive sightings,” DEC spokeswoman Lori Severino said about Bottini’s research.
Otters, who can see underwater and have motion-sensitive whiskers, are hard to count. Frequent wanderers, they can have as many as 90 dens or daytime resting locations. They also tend to be nocturnal and utilize existing beaver and other mammal burrows, coexisting peacefully with the original inhabitants.
But they do leave evidence behind, in the form of tracks and scat full of fish scales and bones and other elements of their diet.
“Due to their large home range, it is difficult to say . . . if the population is growing,” Severino added in a statement.
Now to the air.
Long Island was never known as a prime habitat for bald eagles, but the state began placing breeding pairs elsewhere around New York in the late 1980s in an attempt to restore the population, which had been battered for years by habitat loss and the now-banned insecticide DDT.
In 2006, Long Island had its first confirmed bald eagle nest on the East End. This year, eight nesting pairs have been documented from Great Neck in busy Nassau County to Gardiners Island in Suffolk County. Six eaglets have fledged from those nests.
“Over the last five years the number of eagle nests have continued to increase,” said DEC wildlife biologist Kevin Jennings.
And there is evidence another eight pairs could be nesting elsewhere across Nassau and Suffolk, he said.
eBird, a public bird-sighting website managed by the Cornell Lab of Ornithology, has photos of eagles and their nests in such places as Atlantic Beach, Centerport, Hempstead Lake State Park, Oakdale and Montauk Point.
Mecox Bay in Water Mill, Lake Ronkonkoma and Jones Beach are also possible nest locations, Jennings said.
The newer nests tend to be in more urban areas. That’s unusual because eagles are easily disturbed by human activity and tend to nest in isolated areas with big trees near wide-open spaces and close to water.
Last March, a pair nested on the grounds of Great Neck South School. “These newer nests are showing up in areas we don’t normally expect,” Jennings said.
And to the ocean.
What started in 2015 as the Long Island Shark Collaboration project to trap, tag and release 50 sharks yielded a surprising find — the last catch that year was a white shark less than a year old near Shinnecock. It was the first of that age ever tagged in the North Atlantic Ocean.
The find intrigued the nonprofit research group Ocearch, which spent 2016 and 2017 catching and tagging 20 young great whites — the first documented nursery for the species in the North Atlantic.
The number of young provides researchers with opportunities to tag and track the sharks to learn more about their still-mysterious migratory behavior. It is not necessarily an indicator of more sharks in the area.
“We had not known about the nursery on the South Shore of Long Island,” said Frank Quevedo, a member of the shark group and executive director of South Fork Natural History Museum. “They’ve been here for millions of years. We’re just now learning what the ecology and migratory movements are.”
This May, the museum and Long Island Shark Collaboration will launch a number of surveys to catch and tag white sharks and other shark species as part of what they hope will be a three-year, $300,000 program to add to the data.