Volunteers with the Marineland Right Whale Project have spotted a North Atlantic right whale calf off the coast of Florida, the sixth confirmed sighting this season of a newborn member of the endangered species.

Researchers and conservationists are monitoring the population closely after there were no reported births during the last calving season.

The new mother-calf pair was seen off North Peninsula State Park in Florida’s Volusia County, according to a Facebook post by the Florida Fish and Wildlife Conservation Commission.

In the winter of 2008-2009, the mother, known as No. 3370, gave birth to her first calf, according to the post. The newly discovered calf is her second.

Five other North Atlantic right whales have been reported by the Florida Fish and Wildlife Conservation Commission so far this winter.

The fifth calf was spotted last week just off of Sebastian Inlet, Florida, according to the National Oceanic and Atmospheric Administration and the Florida commission.

The mother was confirmed as 8-year-old right whale No. 4180, according to an Instagram post from the commission. This is her first known calf, the post says.

"The pair were observed resting and nursing at the surface," according to the post.

The fourth calf was spotted Jan. 25 off Jekyll Island, Georgia, with its mother, known to researchers as No. 2503, or “Boomerang,” for a scar on her fluke, according to the commission. Boomerang’s last calf was born during the winter of 2014 and 2015.

Right whales migrate along the Atlantic coastline each year, and birthing grounds have been identified off Florida and Georgia. The mother and calf pairs typically arrive later in the winter and early spring in New England waters to feed, with a large portion of the population congregating in Cape Cod Bay.

The lack of newborns last year was one of a handful of markers and statistical modeling results that point to a declining overall population since 2010, with a heavier toll on female whales and an estimated total population before the recent births of just 411.

Ship strikes and entanglement in fishing lines are the top sources of mortality in the species, which is one of the rarest marine mammals in the world.

The Atlantic States Marine Fisheries Commission recently announced it will begin the process of trying to reduce the amount of lobster fishing gear off the East Coast in an effort to help save the rare whales.

The Fisheries Commission will look to limit the vertical lobster fishing lines in the water by as much as 40 percent, saying in a statement that the drive to reduce lines in the water is "in response to concerns about the North Atlantic right whale population and the potential impacts of whale conservation measures on the conduct of the lobster fishery."

Material from the Associated Press was used in this report