The flock of swans at the Palace of Fine Arts is growing with the addition of a newly hatched baby, according to the San Francisco Recreation and Park Department.

The baby swan, also known as a cygnet, just hatched on Memorial Day and has been named Martha by the swans’ volunteer caregivers, department officials said.

“We are so excited and thrilled to have Martha as part of the Rec and Park family.” said Phil Ginsburg, the department’s general manager.  “We are thankful for all the love and care that our staff and volunteers provide for our animals.”

Martha is the offspring of Blanche and father Blue Boy, who has been busy guarding the nest. Blue Boy met Blanche when he and his sister Bella were moved to the Palace of Fine Arts last January.

There are three more eggs still in the nest that have not hatched yet. If they do not hatch soon, caregivers say they could be infertile and might need to be removed to prevent the mother from continuing to sit on them.

Bella is currently recovering at her birth home in Point Reyes from a foot fracture. Jack Long, the exotic bird breeder who is caring for her, said she is “perfectly well” and should return to the Palace of Fine Arts lagoon in the next few days.

sgaiser@sfexaminer.com

Bay City News contributed to this report.