ナショナルジオグラフィックさんのインスタグラム写真 - (ナショナルジオグラフィックInstagram)「Photos by Keith Ladzinski @ladzinski / Invasive Asian carp breach; they're being collected along the Illinois River, about nine miles south of Lake Michigan. Invasive species in the United States cost the country an estimate 137 billion dollars a year in both management and damage. Asian carp management alone costs an estimated $7 billion, according the Department of Fish and Wildlife. From electric barriers to nearly year-round fishing efforts by the DFW and contracted "carp cowboys," serious work is being being done to keep these fish out of Lake Michigan. Asian carp are incredibly damaging to native fish populations in lakes and rivers because they outcompete other fish for both food and space. If they enter Lake Michigan it could overrun the fish stocks. They were intentionally introduced to help with algae blooms and a variety of aquatic vegetation considered problematic in agriculture. The people that introduced them had no idea what a problem it would eventually become. The fish seen here are taken to pet food facilities for processing. Photographed on assignment for the Great Lakes December issue cover story for @natgeo. Check out Nat Geo's link in bio for more on this story.」12月4日 4時38分