Although an official death toll hasn't been taken, early reports suggest several thousand fish have expired -- mostly mossbunker, called "bunker," a common bait fish. Hundreds have washed up along the shores near Belmar Marina, and still hundreds more float motionless on the surface of the estuary.
The cause of the fish kill is unconfirmed, but most fish kills, officials confirmed this morning, are the result of oxygen depletion.
There's speculation that an influx of larger blue fish just offshore may have pushed a mass of bunker up the river -- squeezing too many fish into a smaller area and sucking the oxygen out of the river.
"This is highly unusual," Matt Doherty, Belmar's mayor, told the Asbury Park Press. "It's alarming, but we want to wait until we get the full test results to really look at what caused this."
Michael A. Meddis, public health coordinator in the Monmouth County Health Department, said the kill appears to be isolated. "We have no other complaints up the coast."