Stalled vessels near Strait of Hormuz could trigger invasive species catastrophe

Over 1,500 ships are idle in the Persian Gulf, hundreds more in Gulf of Oman.

A possible ecological catastrophe could be fueled by stalled ships as conflict over the Strait of Hormuz continues to block traffic on the passageway, scientists say.

The Strait of Hormuz has been a major source of contention since the war with Iran broke out in February. In retaliation to the ongoing conflict, Iran has intermittently caused a decline of tanker traffic through the critical waterway, which connects the Persian Gulf with the Gulf of Oman for the passage of around 20% of the world's oil supply, according to the U.S. Energy Information Administration.

But continued closures at the Strait of Hormuz could trigger a super-spreader event of invasive species as marine organisms attach to the idle vessels and get transported to other ecosystems around the world, according to a paper published Wednesday in the journal Biological Invasions.

This is because prolonged stationary periods can lead to substantial biofouling on ships, according to the paper. Buildup can include microorganisms, algae, plants and invertebrates.

The biofilm grows on the side of the commercial ships and then gets transported around the world as the vessels travel from port to port, Mario Tamburri, a marine ecologist at the University of Maryland's Center for Environmental Science and lead author of the study, told ABC News.

Once invasive species take hold of a foreign ecosystem, it's nearly impossible to get rid of them, Tamburri said.

"We know that these invading invading organisms can cause millions of dollars' worth of damage and impact -- commercial operations like aquaculture and fisheries -- and change the environment," Tamburri said.

One example is the zebra mussels in the Great Lakes, Tamburri said. Native to the Caspian and Black Seas south of Russia and Ukraine, zebra mussels quickly spread in the Great Lakes in the 1980s and are now present in the Mississippi and St. Croix Rivers, according to the National Park Service. They have also now spread to the West Coast due to human transport.

There is little to be done to remove zebra mussels once they have become established in a body of water, according to the NPS. Ecologists have been "battling" with the invasive species for 50 years, Tamburri said.

Ships are typically coated with an "anti-fouling" paint, formulated with chemicals to prevent marine animals from adhering to or growing on them, Tamburri said.

But when ships sit around for a long time, the coatings no longer work well, allowing for the possibility of "extensive growt