Watch Online Free on Watchseries. Caddo Lake is the only natural lake in Texas, a swampy world home to a thriving and delicate ecosystem. But its future is threatened by the appearance of Giant Salvinia, an incredibly aggressive invasive plant from South America that is rapidly overwhelming the body of water. This animated short brings together the real people who are devoting their lives to overcoming his green monster before it’s too late. Because, as one fishing guide puts it, “the lake means everything.”