According to a Fish and Wildlife study, almost 80 percent of non-native species found on the West Coast were first sighted in California.
You might have heard about ballast water. Cargo ships fill their holds with seawater to stay balanced, but that water can also carry invasive species.
Since 1999, ships have been required to either retain ballast water or discharge this water at least 200 nautical miles away from shore — and over 90 percent of them do.
But invasives remain a problem well beyond the ports. Researchers say recreational boating also plays a part. Small vessels can spread around species that have been introduced by cargo ships.
There’s another less-obvious way invasive species gets introduced —and it’s cost California millions of dollars.
After “Finding Nemo” was released, people started flushing fish and plants down the drain, or taking them to the ocean and dumping them in. It led to a pulse of invasion around the country.
A study from UC Davis found that aquariums contribute to a third of the world’s worst aquatic and invasive species.