Invasive Species Threat To US Waters

by Patriot Daily

Published on Reuters

US waters are threatened by invasive species that may spread deadly diseases to people and wildlife, impair water supply infrastructure, harm ecosystems, cause twice the annual economic damage of all natural disasters, and are linked to half of the decline of endangered species.

When large ships are not transporting cargo, the ships pump coastal waters and all the living organisms into their ballast tanks while at foreign ports to obtain balance. When closer to our shores, the ballast water is exchanged with ocean waters, but the exchange does not eliminate the invasive species, which then are discharged into our waters. The 9th Circuit has directed the EPA to regulate this pollution while Congress has reached an impasse on legislation.

Ballast water is needed to provide balance for changes in the ship's weight. The problem is that the ballast water contains thousands of invasive species which are then carried in the ballast tanks of the ship. When a ship reaches the next port, changes in the cargo load may require changes in ballast, and thus the ballast water is discharged into a new ecosystem. When the ships return to the US, then the invasive critters are released into US waters. Each year, "more than 21 billion gallons of ballast water" is discharged into US waters.

The invasive species range from "microscopic bacteria to weeds, fish, crabs and mussels." Each day, more than 10,000 marine species "hitch rides around the globe in the ballast water of cargo ships."

These invasive species then create enormous problems for our water supplies, environment and people.

They can spread disease. A 2001 EPA report disclosed that a cholera bacteria was "possibly" released by a Chinese freighter in Latin America, which caused the deaths of 10,000 people. Ships from Latin America then imported this cholera in their ballast tanks to the Mobile, Alabama port. Fortunately, the cholera bacteria was discovered in oyster and finfish samples so that no one was killed in the US.

Deadly diseases may be spread to wildlife as well as people. For example, it is believed that ship ballast water likely transported Viral Hemorrhagic Septicemia (VHS), an invasive species virus, to US waters, resulting in bloody, hemorrhaging "fish kills involving more than 30 species, including valuable sport fish such as salmon, trout, walleye, muskie, bass and perch."

They clog the water pipes and infrastructure. For example, two decades ago, little quagga and zebra mussels hitched a ride from Eastern Europe to the Great Lakes. In 6 years, the invasive species caused $500 million in damages to the regional economy by clogging water intake pipes. Last year, the mussels spread to Lake Mead in Nevada and on to Southern California, where one water district projects it will cost at least $15 million a year to try to extinguish aqueduct infestations.

They threaten native species: Invasive species are a "major or contributing cause of declines for almost half the endangered species" in the US. The absence of natural predators allows the invasive species to "multiply rapidly and quickly take over an ecosystem."

The threat by invasive species is enhanced because they are "almost impossible to remove" and thus scientists, industry officials and land managers have concluded that "invasive species are one of the most serious, yet least appreciated, environmental threats of the 21st century." Continued...

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