A few of you have written in to point out the recent media coverage of a possibly controversial take on non-native fish introductions. Noting that the risk of negative ecological impacts following fish introductions is typically less than 10%, Dr. Rodolphe Guzman, a biologist at Bournemouth University, posits that this means the majority of introductions are safe, and considers the risk of invasion to be only one factor in the decision of whether to bring non-native species into aquaculture. Read more in this interview from Reuters or this writeup in Practical Fishkeeping. You can also check out the Gozlan article, "Introduction of non-native freshwater fish: is it all bad?" in the journal Fish and Fisheries (abstract only).