Researchers at the Royal Botanical Gardens (RBG) have counted as many as two million large and small

Researchers at the Royal Botanical Gardens (RBG) have counted as many as two million large and small goldfish this year in Hamilton Harbour, Canada, fish that are likely descendants of people dropping unwanted pets in the water.

The fish, which are threatening the local ecosystem, seem to be thriving thanks to climate change, and poor water conditions that have discouraged native species from flourishing.

The problem of invasive goldfish pets released into ponds and lakes isn’t limited to Hamilton. More examples here,here,hereandthere 

Fromhere