The death toll for bottlenose dolphins continues to rise as four more washed up on South Jersey beaches Thursday night and Friday and one more was found floating just off shore.

The total to have washed ashore in the state since July 9 was 25 as of 5 p.m. Friday. One more dead mammal was identified floating in the ocean Friday morning in Avalon.

The most recent to wash ashore were in Atlantic City Friday afternoon, in Ocean City on Thursday evening and in Avalon and North Cape May on Friday morning.

Marine Mammal Stranding Center co-director Bob Schoelkopf said it was a good thing a storm pushed beachgoers off the shore Thursday afternoon in Ocean City.

“(The dolphin) was bit by a sand tiger (shark) and, chances are, if anyone would have tried to hold it down they would have been hurt,” he said, saying the shark would likely have still been nearby.

In Avalon, one dolphin was found along a jetty and another floating in the water, Schoelkopf said.

The floating dolphin remained in the water because the U.S. Coast Guard was not able to assist the stranding center, Schoelkopf said.

The dolphin in Atlantic City was 8 feet long and weighed 450 pounds, Schoelkopf said.

The cause for the high number of dolphin deaths is still unknown. The National Oceanic and Atmospheric Administration issued an alert to stranding centers asking them to include additional tests in the necropsies to help determine the cause.

On Thursday, the DEP said the deaths appear to be linked to a natural disease cycle, not water-quality issues, spokesman Larry Hajna said.

Previously, fishermen have spotted at least five dead dolphins floating of Barnegat Light and Cape May, but the stranding center is only keeping count of the ones brought into the center.

Schoelkopf said fishermen who are reporting the dead dolphins often leave the site or do not have accurate coordinates to help locate the mammal.

Necropsy results for one dolphin found in Seaside Park was confirmed to have a virus that was responsible for a mass die-off in 1987, Schoelkopf said. The morbillivirus, a virus similar to measles, killed nearly 750 dolphins between New Jersey and Florida. Four of the dolphins have died of viral pneumonia.

Contact Anjalee Khemlani:

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