Breaking News: Protesters march on Pakistan PM Nawaz's house

U.S. ports at risk of species invasions from dumped ballast water

May 7, 2013 at 4:50 PM   |   Comments

OLDENBURG, Germany, May 7 (UPI) -- Several U.S. cities are on a list of "hot spots" at risk of invasive species hitching rides in ballast water carried into ports by cargo ships, researchers say.

San Francisco, New York and Los Angeles are on the list created by researchers at the University of Oldenburg in Germany who studied the threat level of invasive species faced by 1,400 ports across the globe, NewScientist.com reported Tuesday.

Empty ships routinely take on seawater as ballast before beginning a voyage to keep them stable at sea, then dump it in the port where they take on cargo, along with invasive species native to wherever the water was taken on.

Ballast water is probably the leading cause of alien species invasions worldwide, the researchers said.

Invasions are more likely to occur if the water at both ports is of similar temperature and salinity, they said, and are more likely with warmer waters, which usually contain more species.

The findings could help port officials in their efforts to control invasive species, Oldenburg researcher Hanno Seebens said.

"Usually port authorities cannot check all ships," he said. "Our model can help inspectors identify the ships with the highest probability of carrying potentially invasive species."

© 2013 United Press International, Inc. All Rights Reserved. Any reproduction, republication, redistribution and/or modification of any UPI content is expressly prohibited without UPI's prior written consent.
Recommended UPI Stories
Featured UPI Collection
2014: The Year in Music [PHOTOS]

2014: The Year in Music [PHOTOS]

Most Popular
Southwest U.S. could face 35-year 'megadrought'
Hurricane Katrina nine years later
Latvia boasts world's first net for migrating bats
Apple reportedly delays launch of rumored iWatch
New space debris monitoring facility set for Australia
Trending News