image: Mangroves comprise a group of terrestrially derived coastal plants that evolved traits to disperse by ocean currents. view more
Credit: Image courtesy of Tom Van der Stocken.
Researchers report global patterns of mangrove dispersal. Mangroves--trees or shrubs that grow in salt water along tropical and subtropical shorelines--are ecologically and socioeconomically valuable. Mangroves are also highly susceptible to climate-driven sea level rise. Buoyant mangrove seeds and fruits, called propagules, disperse via ocean currents, providing a mechanism for range shifts in response to climate change, but the spatial scale of such dispersal is unknown. Tom Van der Stocken, Dustin Carroll, and colleagues used a high-resolution ocean current model to simulate global propagule trajectories over a period of 1 year. Dispersal frequently occurred along the coasts, with no dispersal observed between opposite sides of the African or American continents. The authors calculated the degree of connectivity between various regions as the probability of a propagule released from one region taking root in a different region. The authors found significant connectivity between the Tropical East Pacific and the Galapagos Islands, which were in turn connected with Central Polynesia, suggesting that archipelagos could act as stepping stones for trans-Pacific dispersal. The authors also observed direct and reciprocal connectivity between opposite sides of the Indian Ocean. The effective dispersal distance was sensitive to the time that viable propagules spent floating. According to the authors, the results illuminate present mangrove distributions and possible responses to climate change.
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Article #18-12470: "Global-scale dispersal and connectivity in mangroves," by Tom Van der Stocken, Dustin Carroll, Dimitris Menemenlis, Marc Simard, and Nico Koedam.
MEDIA CONTACT: Tom Van der Stocken, Jet Propulsion Laboratory, Pasadena, CA; tel: 818-354-1784, 626-818-5313; e-mail: <tom.van.der.stocken@jpl.nasa.gov>; Dustin Carroll, Jet Propulsion Laboratory, Pasadena, CA; e-mail: <Dustin.Carroll@jpl.nasa.gov>
Journal
Proceedings of the National Academy of Sciences