Saskatchewan : Province on alert for invasive aquatic species

And on the other end of the scale from endangered species - species which are not wanted (well, at least, not where they have not historically been).

“Saskatchewan’s lakes and waterways have significant environmental, economic and recreational importance and aquatic invasive species such as zebra and quagga mussels pose a serious threat. Proclaiming Aquatic Invasive Species Awareness Week in Saskatchewan will help inform and educate the public on this critical issue.”