Southwest Florida's most famous family has likely lost an egg.
Harriet and M15, a bald eagle pair watched online by millions, are raising their latest generation along Bayshore Road in North Fort Myers.
The duo returned during the fall and have since produced two eggs, one of which hatched. The eaglet, called E9, seems to be doing well, but the other egg, the first one laid, will likely not hatch.
"We're definitely well beyond the hatch window that we normally see, so unfortunately we believe the egg isn't viable," said Virginia "Ginnie" Pritchett. "We'll have to see what Harriet and M (15) do, to see if they dispose of the egg or just leave it in the nest."
The Pritchett family owns the land where Harriet and M15 nest. In 2012, the Pritchetts installed a streaming camera to broadcast the family's daily life to viewers all over the world.
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Called the Southwest Florida Eagle Cam, the website that hosts the video stream has tallied more than 72 million viewers, with more than 32,000 computers tuned in at any given moment.
But some of the joy viewers finding in watching the eagles has turned into anxiety as the one egg still has not hatched.
"It was laid first, and we saw that they had started to bury the egg in the nest," Pritchett said. "They started to put moss and materials over the egg and we had never seen that. They probably knew it wasn't viable."
Egg No. 2, a hatchling now called E9, emerged from its eggshell casing on Dec. 31. Egg No. 1 should have hatched at least a few days earlier.
Bald eagles typically lay two eggs, and the older, larger eaglets sometimes kill their smaller siblings to reduce competition for food.
The U.S. Fish and Wildlife Service says more than 50 percent of eagles don't survive their first year.
Anything from a lack of proper nutrition to not being turned over often enough can cause an egg to become nonviable. Bacteria can also penetrate the shells, and the fragile egg casing can crack or break before the eaglet is fully developed.
Jim Beever, who spent years studying eagles for the Florida Fish and Wildlife Conservation Commission, said these birds face many challenges when trying to raise the next generation.
"Knowing all that can go wrong from copulation to hatching, it seems miraculous that so many healthy, hungry bald eaglets successfully emerge from their eggshells," Beever said.
What will happen to the unhatched egg?
"I have seen non-viable eggs pushed out of the nest by one of the adults," Beever said, "and I have read that some may break and eat an unfertilized egg."
Harriet was originally paired with a male eagle nicknamed Ozzie. This pair produced dozens of eaglets over the course of more than 20 years, but Ozzie was usurped by M15 in 2015.
Ozzie suffered a series of injuries while fighting M15, and he was taken to a local wildlife rehabilitation center for treatments.
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He was released back into the wild after three months of care, but M15 delivered fatal blows to Ozzie when the two sparred one last time for Harriet's companionship. Last year, the pair fledged two eagles, although one was briefly hospitalized after becoming entangled with fishing line in the nest.
Pritchett said well-wishers have been sending messages and writing online posts to express their concerns.
"Folks do get emotional," she said. "They see how E9 is flourishing and they want to see that for this other egg, but we tell everyone that wildlife isn't always warm and fuzzy. These things unfortunately happen."
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