Scotland Neck, N.C. — Damage to a wildlife sanctuary in Halifax County from the weekend snowstorm killed at least 20 birds, officials said Tuesday.

The Sylvan Heights Waterfowl Park will remain closed until the end of this week so staff members can repair about 40 aviaries that collapsed Sunday under the weight of ice and snow and locate and secure birds that escaped the broken pens. The bulk of the damage occurred at Sylvan Heights’ adjacent breeding center.

"This is just unimaginable," said Brent Lubbock, Sylvan Heights' marketing director. "We're on our third day, and we're still knocking snow off (the nets atop the aviaries)."

The dead birds included one of only three female black-headed ducks in captivity in the U.S., officials said.

"It's been heart-breaking to see all of this," refuge co-founder Ali Lubbock said.

Ali Lubbock said staff members weren't yet sure how many birds they would find or their condition. She said they are treating the situation like medical triage.

"We had to weigh which ones were the highest priority based on endangered and threatened status and then move down," she said. "You try to assess which birds are going to succumb faster than others, and you move steadily accordingly."

Sylvan Heights is home to about 4,000 birds. The storm caused about $20,000 in damage, officials said.

"We've been through tornadoes, hurricanes, fires, oil spills, and this snowstorm has probably caused more damage, especially to the breeding center, than we've ever seen," Brent Lubbock said.

Disney's Wild Animal Kingdom and a zoo in New York have agreed to send several waterfowl husbandry professionals to assist the Sylvan Heights staff. Volunteers from the N.C. Zoo Society are helping with the clean-up of the damage and the care of the birds.