A swan song for Romeo, Juliet

One might think the entire community were giving birth.

People from far and wide have been making daily trips to monitor Romeo and Juliet, the city's pair of swans nesting near the Public Garden lagoon.

People have been calling the Parks Department to offer observances and get progress reports. Juliet laid her first eggs ever in late May, and residents have been acting as if they are expectant parents since.

''We come here every day looking for the baby swans, and we're always disappointed," Cambridge resident Jennifer Kritz said yesterday. She paused mid-sentence when Romeo and Juliet stood up and nudged their beaks into their nest. For a moment, everyone nearby went silent. Then, the swans went back to warming their eggs.

''Isn't it exciting?" exclaimed Joan Ditzion, who had accompanied Kritz on the swan mission.

But the excitement may be drawing on far too long. The baby swans were expected in late June. Then, it was the first week of July. Now, Parks Department officials say they fear that all the anticipation may be for naught.

Yesterday may have marked the last possible due date for the eggs, according to a Zoo New England specialist. And if the fuzzy gray cygnets don't poke their beaks out soon, the first swan babies ever bred in the Public Garden may never hatch.

''I'm keeping my fingers crossed, but time's running out," said Frederick Beall, general curator and aviculturist for Zoo New England. ''If they don't hatch in the next three to four days, then they're no good. Either they're not fertile or they've died somewhere in the development stage."

Parks officials planned to call specialists this morning for advice about what to do, whether due date calculations may have been flawed, and how long to wait before trying to dissect the eggs.

All manner of environmental factors can lead to unhatched cygnets. The eggs may have gotten too cold or they may not have been properly fertilized. There is no way to tell whether the eggs are still viable until they are cracked open after the gestation period ends. The eggs would show no outward signs of change if the embryos died, and a mother swan often would not know the difference.

''A lot of times, they're so driven about hatching, they just sit and sit and sit," Beall said.

Determining the gestation period for Romeo and Juliet's offspring has been somewhat of an imperfect science. When Mute Swans such as Juliet begin laying eggs, they typically lay one every other day, and the gestation period ends 35 days after the last egg. Juliet began laying eggs around May 20, but it's unclear how many eggs there were. Because the swans have been so protective of their nest, no one has been able to get an accurate count. Park rangers have only had glimpses from a distance and only during brief moments when the swans have left the nest.

''We can't exactly ask them to move," said Mary Hines, spokeswoman for the Boston Parks and Recreation Department. Hines said nearly everyone has come up with a different number -- from five to nine.

If she laid five eggs, they should have hatched July 4. Nine should have hatched yesterday.

''I hope they hatch, it would be nice," Beall said. ''If it's past, they're not going to hatch."

If their babies never appear, Romeo and Juliet probably won't show any outward signs of grieving, though the swans may go through a psychological process that specialists can't measure, Beall said.

As for the community, that's another question. Romeo and Juliet might be the nation's most celebrated pair of swans, feted each spring with a parade as they returned to the Public Garden from wintering at Franklin Park Zoo. The mayor's office has called them Boston's ''most famous feathered friends."

In the 15 summers the city has kept swans at the lagoon, Romeo and Juliet, who are between 5 and 6 years old, are the first to breed.

''Everyone in the community kind of feels they have ownership of them," Hines said.

People have been calling her office, trying to tip off rangers when they believe the swans are acting abnormally, asking about whether the swans are eating enough or whether the nearby ducks might be bothering them.

''They all want to know why they haven't had their babies yet," Hines said.

News that the nest they have visited so religiously may never produce baby swans hit many spectators hard yesterday.

''Oh, no!" said Karen Dana, a Beacon Hill resident who checks on the swans every day. Eating her lunch on a bench overlooking the nest, Dana remarked that the eggs couldn't possibly have gotten cold. Every time she's here, she said, one of the swans is sitting on the nest. ''I guess they could have gotten up at night, but that seems unlikely."

Marie LeBlanc of Norwood stood a few steps away, her brow deeply furrowed. LeBlanc has visited the nest once a week for the past month. ''I just like watching them." LeBlanc's voice trailed off.

Then, with a fretful note, she said, ''I just hope they're OK."

Donovan Slack can be reached at dslack@globe.com