About 100 baby loggerheads recently hatched and made their way into the Atlantic in the first successful sea turtle nesting observed on Maryland’s portion of Assateague Island.

The turtles emerged over several weeks in September from a single nest in a section of Assateague Island National Seashore beach where access is limited, the National Park Service said.

Park rangers have noticed turtle nests in the past, but the eggs never hatched, likely because temperatures didn’t stay high enough to incubate the turtles, said Bill Hulslander, chief of resource management for the national seashore.

“This is a unique event for us,” he said. “This just happened to be the right year and the right conditions for the nest to finally fully develop and to hatch a significant number of turtles.”

Loggerheads rarely nest north of Virginia, and even there, only about eight to 10 nests are spotted each year, said Justin Perrault, associate director of research for the Loggerhead Marinelife Center in Juno Beach, Fla.

Some research is being conducted to explore a hypothesis that another species, leatherback sea turtles, is migrating farther north as ocean temperatures rise, he said. That species is found mostly in the tropics.

It’s possible that climate change is also allowing loggerheads to extend their traditional territory, Perrault said.

Assateague rangers first noticed the loggerhead nest in late June, Hulslander said. They surrounded it with wire netting that keeps predators out but has openings large enough for baby turtles to pass through.

Female turtles often lay four or six clutches of eggs during nesting season, which peaks in June and July, and it can take two months or more for them to hatch.

The Assateague turtles started emerging in early September, and eggs continued to hatch into the middle of the month, he said. While eggs can hatch within 50 or 60 days of being laid in Florida summer heat, lower temperatures require a longer incubation, said Adrienne McCracken, field operations manager for the loggerhead center.

In past years, when loggerheads have nested on the island, it apparently wasn’t warm enough for the turtles to grow and eggs to hatch. Hulslander said park rangers inspect the nests and eggs if they haven’t hatched after four months, and in the past have found the turtles undeveloped.

This time, “we just had the right conditions on the beach for them to develop and hatch,” he said.

Hulslander said the hatching emphasizes the importance of maintaining undisturbed beaches like Assateague’s to provide habitats for turtles and other creatures.

“We have a naturally functioning beach,” he said. “It is an undeveloped barrier island basically from the Ocean City inlet down to the Chincoteague inlet.”

Development can make it hard for turtles to successfully nest because it increases erosion and often introduces artificial light that can be disorienting, McCracken said.

“It can cause turtles to crawl the wrong way or avoid a section of beach if it’s too bright,” she said.

Loggerhead turtles are federally protected under the Endangered Species Act. They have been considered to be a “threatened” species since 1978.

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