Volunteers at the Marine Mammal Stranding Center (MMSC) has reported that the dolphin that has strayed into a New Jersey river has died despite efforts to save it.

The cetacean was first spotted in the South River on Wednesday but volunteers from the MMSC,  a private non-profit marine rescue organization in Brigantine, New Jersey, hoped that it would return into the ocean with the high tide.

The dolphin remained stranded for the second day prompting workers to go into the water in an effort to coax the animal into deep water. They gently pushed the animal with a baykeeper boat and guided it toward the Raritan Bay.  

The center said that the dolphin seemed to be swimming to the bay by Saturday morning with volunteers following it from a distance. One volunteer though noticed that the animal was swimming into a shallow area and alerted the center staff immediately.

It turned out that the animal is in bad state. The dolphin, which was estimated to weigh about 400 pounds and measure over 9 feet long, was having seizures and having difficulty breathing when a rescue team arrived. The rescuers then pulled the animal from the water to bring it to a veterinarian but it died during transit.

"Despite their efforts to float the animal, it had no energy left to swim, and so they carried it back to our dolphin transport truck, where it died," the center said. "We know that this was an older animal but we will know more after the state veterinary pathologists examine the dolphin. "

MMSC director Sheila Dean said that they think that the dolphin actually went to the river to die just like in the case of a number of marine animals that they have tried to save.

"We suspect that he was an old male dolphin that had gone up the river to die," Dean said. "We have seen this about 50 times out of the 4,700 marine mammals that we have attempted to rescue."

Despite the failed attempt to rescue the dolphin, the MMSC thanked those who supported the effort. It said that they hope people will be more aware now of the diversity and fragility of the state's marine life.

The MMSC responds to strandings of marine animals such as dolphins, whales, sea turtles, and seals that have washed ashore.  It urges those who find stranded animals to contact them at 609-266-0538.