, Volume 62, Issue 2, pp 145–149 | Cite as

Detection of inconspicuous epiphytic algae supporting food webs in seagrass meadows

  • Christopher L. Kitting
  • Brian Fry
  • Mark D. Morgan
Original Papers


Detritus from common seagrasses and other marine angiosperms may often be a less important basis for estuarine food webs than previously believed. In NW Gulf of Mexico seagrass meadows, epiphytic algae have high productivities, palatability, and a more important trophic role than common large plants have. Interdisciplinary field experiments show (1) intensive night-time ingestion of epiphytes by various invertebrate “detritivores”, (2) very high productivity of epiphytic algae on seagrasses, and (3) assimilation of epiphytes rather than seagrasses, as measured by δ13C comparisons. These combined data show that many naturally concentrated and potentially competing invertebrates in Gulf of Mexico seagrass meadows feed largely on the algal overgrowth on seagrass blades, even when such algae appear to be sparse. Primary productivity of these epiphytic algae can equal that of the seagrasses, per blade or per unit biomass. Animal δ13C values tracked epiphytic values rather than seagrass values when comparisons were made over six sites. These measurements reinforce the view that epiphytic algae can be the primary basis of the food web in seagrass meadows.


Biomass Assimilation Detritus Seagrass Meadow Important Basis 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag 1984

Authors and Affiliations

  • Christopher L. Kitting
    • 1
  • Brian Fry
    • 1
  • Mark D. Morgan
    • 1
  1. 1.Marine Science InstituteUniversity of Texas at AustinPort AransasUSA

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