An interim report, released from a larger, U.S. federal study on invasive Asian Carp, has identified storm sewers, bird feces, and even Asian Carp sperm as possible sources of environmental DNA (eDNA) that could be behind positive eDNA hits found in the Great Lakes and Chicago waterways. Researchers are trying to iron out the eDNA method, which is useful for detecting species in low abundance, but is unable to confirm the presence of live fish.
Invasive goldfish, which belong to the carp family, could be a threat to both native fish species and the water clarity at Lake Tahoe in California and Nevada, Reuters reported. Goldfish found in the lake have weighed as much as 1.8 kilograms (4 pounds), and researchers say the waste excreted by the fish can encourage algae growth.
Invasive species cost Europe $US 16 billion each year, according to a study released this week from researchers at the Italian Institute for Environmental Protection and Research, Reuters reported. The invaders can harm both the environment and public health.
Farmers in Australia’s Goulburn River Valley are fighting a move by government-owned Goulburn-Murray Water to shut down irrigation channels that provide water to some rural areas, The Australian reported. The water company hopes to reduce water waste and costs, but the farmers say they are squeezing out small farms in favor of commercial operations.
Athens’ heaviest downpour since 1961 has created power outages and flooded city streets, Reuters reported. Over a 3-hour period, as much as 130 liters (34 gallons) of water fell per square meter (10.7 square feet) in some areas, officials said.