Links to more information about the invasive seaweed issue:
http://blogs.scientificamerican.com/expeditions/2013/05/22/usc-dornsife-scientific-diving-an-analysis-of-sargassum-horneri-ecosystem-impact/
http://californiadiver.com/the-invasion-of-the-devil-weed-sargassum-horneri-invading-california-waters/http://www.ocregister.com/articles/sargassum-646894-kelp-california.html
Sargassum horneri, Catalina
