Bill Hollingsworth put on black gloves, grabbed a plastic bag and walked across the Route 52 causeway to pick up the feathery carcass of a herring gull on the asphalt.

“We cleaned the roadway off yesterday,” said Hollingsworth, executive director of the Humane Society of Ocean City, “so this is from this morning, or last night.”

The work has become an almost daily chore for the organization, which has found more than 50 dead or injured birds along the bridge since it fully opened in mid-May, and no one is sure why.

By comparison, only a handful of birds are found each year on similar bridges, such as the Route 72 causeway onto Long Beach Island and the Route 37 causeway to Seaside Heights.

“I went through all our reports, and we’ve only had a couple since January,” said Gayle Tomkinson, an animal control officer in Stafford Township, which handles animal removal on the Dorland J. Henderson Memorial Bridge to Long Beach Island.

“I’d say we have no more than four to six a year,” said Jim Bowen, director of Toms River Animal Control. “We don’t have that many.”

Dead gulls were never a problem on the old causeway between Somers Point and Ocean City, and no one predicted they might become one when the new causeway was built.

The leading theory is that something about the wind current through that part of the Great Egg Harbor Bay sends birds veering into cars or the roadway itself.

The Humane Society issued an advisory Thursday asking motorists to be cautious of the birds when traveling across the bridge. Hollingsworth said they have also asked the city and state to install signs to caution drivers to look out for gulls, similar to those posted for turtles that cross low-lying roadways elsewhere.

Many gulls rest on the railing at the northern side of the causeway’s lowest section, on the largest of the Rainbow Islands, and apparently look for fiddler crabs and other food in the marsh below.

Hollingsworth said he has witnessed birds struggle to take off from that location, and he thinks some may drift backward into traffic. Their flight may also be disrupted by large trucks passing by.

But why that would be a problem with this causeway and not its previous incarnation is unclear. Even at its lowest point, the new structure is higher, and it slopes up and down, whereas the old causeway was mostly level.

Whatever is creating the issue, it is frequently fatal. Most of the birds are found dead; of 10 found injured, two were rehabilitated, while the rest were so badly hurt they had to be euthanized.

“Broken backs, broken feet, broken wings,” said Hollingsworth, listing the injuries the Humane Society has seen.

The Ocean City Police Department and the state Department of Transportation have been monitoring the situation, trying to figure out what is going on and how to prevent it. The DOT has also reached out to groups such as the New Jersey Audubon Society for advice.

“This is an unusual situation,” DOT spokesman Joe Dee said. “This is a very unusual situation.”

The obvious solution seems to be to stop the birds from landing on the causeway, Hollingsworth said, if the problem is primarily with perching and taking off again.

“The simple remedy is to put bird spikes so they don’t rest on the guardrail,” he said. “It’s inexpensive, and it doesn’t change the bridge at all.”

Hollingsworth said he wants the issue solved sooner rather than later, not only for the sake of the gulls but also for the well-being of his employees. They are out on the road so frequently it is a safety hazard, he said, and the organization recently bought reflective vests to be safer.

After collecting the most recent bird’s carcass Thursday morning, Hollingsworth went underneath the structure to see what the birds were looking at so eagerly in the wetlands below.

When he looked out over the edge, about 6 feet above the mud and grass, hundreds of fiddler crabs scurried back into their holes. A few gulls were down there as well, away from the apparent danger of the road above.

“These are the smart ones,” Hollingsworth said.

Contact Lee Procida:

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