NEW YORK (CBSNewYork) -- A bottlenose dolphin that's been swimming in the East River doesn't seem interested in heading back out to sea.
It was first seen Wednesday off the FDR Drive near East 96th Street. The mammal was spotted in the water again Thursday morning.
Onlookers flocked to the water's edge to take pictures and observe the dolphin.
"I saw my friend, there were people with cameras. He said there's a dolphin in the water," said Queens resident, Mike Caponigro.
"The dolphin was diving and swimming normally and there were no observable injuries noted," The Riverhead Foundation for Marine Research and Preservation wrote on its Facebook page.
The group is continuing to monitor the dolphin's movements.
It is unusual for dolphins to swim in the waters around Manhattan, but it is not unheard of. In 2010 there were four separate sightings.
Dolphins are used to a cleaner environment than the East River, and the 30-billion gallons of sewage and water that the river contains may not be good for the dolphin's health.
"They come from very pristine waters, so it's conceivable their immune system may be unprotected from these pulses of bacteria," said Riverkeeper John lipscomb.
For now, experts told CBS 2, that the dolphin is behaving normally. It is an eight-foot long adult and appears to be well nourished.
for more features.