This looks like something out of a nightmare.

Mass animal die-offs are always fascinating, yet scary. This one happened right in our home state.

Tens of thousands of dead bunker fish could be seen floating in the Shinnecock Canal in Hampton Bays Monday. The haunting videos and images have shown up all over the internet, causing some to speculate that maybe the waters are contaminated, or it was some sort of bizarre mass suicide.

The truth, however, looks to be a little less dramatic.

The New York Department of Environmental Conservation said the fish were probably chased into the canal by other predatory fish (perhaps, blue fish). The DEC had closed the locks on the canal Monday. This trapped the thousands of fish. Once so many of them were crammed into the relatively small space, they suffocated due to lack of oxygen.

In spite of the reassurances, the Suffolk County Health Department is collecting water samples to test for pathogens.