Spread the Word Not Halophila

Vimeo Link:  https://vimeo.com/263671322

YouTube Link: https://youtu.be/Q6Iov7BkKiY

Team Members:

Colin Howe, University of the Virgin Islands
Tanya Ramseyer, University of the Virgin Islands
Lauren Olinger, University of the Virgin Islands
John Cassell, University of the Virgin Islands
Elizabeth Brown, University of the Virgin Islands


Caribbean seagrass communities provide juvenile fish areas to forage for food, protection and, nursery habitat. Starting in 2002, an invasive seagrass Halophila stipulacea colonized many Caribbean islands displacing native seagrass. The impacts to juvenile fish that utilize seagrass communities remains under studied. We deployed fish traps in Frenchman, Lindbergh and Sprat Bay for 24h intervals in patches of bare sand, H. stipulacea and, native seagrasses Thalassia testudinum and Syrinodium filiforme. Relative total abundance of juvenile fish was identified to the species or family level and compared across treatment habitats for each trap. The results showed higher abundances of juvenile fish in the invasive seagrass compared to the native seagrass; mostly comprised of nocturnal carnivores like snappers and grunts (Family Lutjanidae & Haemulidae). The native seagrasses showed significantly higher species diversity compared to the invasive seagrass. The result show reduced family diversity and altered juvenile fish abundance within the invasive seagrass.

Original Publication: 

Olinger, Lauren, Sarah Heidmann, Allie Durdall, Colin Howe, Tanya Ramseyer, Sara Thomas, Danielle Lasseigne, Elizabeth Brown, John Cassell, Michele Donihe, Marieke Duffing Romero, Mara Duke, Damon Green, Paul Hilbrand, Kristin Wilson Grimes, Richard Nemeth, Tyler Smith, Marilyn Brandt., 2017. Altered juvenile fish communities associated with invasive Halophila stipulacea seagrass habitats in the US. Virgin Islands. Plos One 12(11): e0188386: 43121

Link to Publication: https://doi.org/10.1371/journal. pone.0188386

Support Provided by: National Science Foundation Grant No 1355437

By the Numbers

Over 40,000 students in 50 US states, the US Virgin Islands, and 25 countries participated as judges in the 2016 Ocean 180 Video Challenge.