Investigating Unusual Number of Dolphin Deaths This Summer

One of two dolphins stranded on a Ocean Ciyt beach this summer
Photo: shorenewstoday.com

The NJ Department of Environmental Protection’s Division of Fish and Wildlife has reported that it is monitoring an unusually high number of dolphin deaths that have been reported over the past several weeks and is working with the nonprofit Marine Mammal Stranding Center in Brigantine to better understand the cause of the mortalities.

While the underlying cause of the deaths has not been confirmed, they appear to be part of a natural disease cycle and not related to water quality, which has been excellent this summer.

Since July 9, the Marine Mammal Stranding Center has responded to 21 dolphin deaths along the New Jersey coast. Necropsy results available so far have confirmed that four of the dolphins died of pneumonia. Federal officials are looking into larger than normal numbers deaths of dolphins in New Jersey and other Mid-Atlantic states, although at this time it is not known if there is any connection.

Twenty bottlenose dolphins and one common dolphin have been reported dead or dying on or near beaches scattered from Monmouth County to Cape May County. Dolphins of varying sizes and ages have been affected. The public is advised not to approach dead or dying dolphins.

“We are offering whatever assistance we can, including the use of our conservation officers and our boats to recover dolphins as we work to understand the cause of these deaths,” said Division of Fish and Wildlife Law Enforcement Chief Mark Chicketano.

Morbillivirus, a naturally occurring virus in dolphin populations, was confirmed in one of the recovered dolphins. Results are pending on additional dolphins to help determine if morbillivirus is present in those animals. Morbillivirus was linked to the deaths of 90 dolphins in 1987 off New Jersey.

“Dolphins swim close together in pods. Diseases spread between animals when they surface to breathe,” said Robert Schoelkopf, Director of the Marine Mammal Stranding Center. “There is no evidence that the deaths we are seeing this summer are in any way related to water quality.”

The state’s Cooperative Coastal Monitoring Program, a joint state, local and federal effort, conducts routine testing of bathing beaches. Water quality has been excellent, with no closures of ocean beaches due to elevated bacteria levels.

Noting that there’s an increased risk of sharks feeding on dead or dying dolphins, Schoelkopf strongly cautioned the public not to approach the animals or attempt to bring them ashore. Pets should also be kept away from them.

If you see a dead or dying dolphin, contact the Marine Mammal Stranding Center’s 24-hour hotline at (609) 266-0538.