NEW YORK (Reuters) - New York City's wildlife-rich saltwater marsh islands could disappear within five years due to rapidly increasing degradation that may be caused by the dumping of treated sewage, a study showed on Thursday.
The islands of Jamaica Bay, a sensitive bird and fish habitat near John F. Kennedy airport, have long been observed to be vanishing.
But the new study by the Jamaica Bay Watershed Protection Plan Advisory Committee says they could disappear by 2012, or 12 years earlier than a previous estimate by the city's Department of Environmental Protection
New York City created the committee in 2005 to help the department protect one of the city's last remaining wilderness areas, which is home to more than 80 fish species.
Some 20 percent of North America's migratory bird species stop in Jamaica Bay's marshes, which also provide flood protection for humans, the report said.
The department previously estimated that from 1924 to 1999 the bay lost half of its tidal wetlands, and that the loss accelerated over time. Evidence from satellite imagery and aerial photography taken between 2003 and 2005 shows recent losses have been even more rapid.
Tidal creeks on the marsh islands are expanding and vegetated areas are turning into mud flats, then sand flats, as they disappear, the study said.
The report says the exact cause is unknown but lists one possibility as the high nitrogen content of treated sewage -- a conclusion that has been disputed.
The committee reiterated its call to immediately cut nitrogen discharges into the bay.
Coastal development and dredging could also be hurting the wetlands by cutting off sediments that feed the marshes, the study said.
One official with the Department of Environmental Protection called the link to nitrogen contamination "weak."
"To find that smoking gun and justify spending the capital dollars to upgrade the plants has been frustrating," Angela Licata, deputy commissioner of the department, told The New York Times.
A department spokesman referred questions to the department's own report, which is due out in October.