Estuaries and Coasts

, Volume 36, Issue 1, pp 36-43

First online:

Open Access This content is freely available online to anyone, anywhere at any time.

Quantifying the Loss of a Marine Ecosystem Service: Filtration by the Eastern Oyster in US Estuaries

  • Philine S. E. zu ErmgassenAffiliated withDepartment of Zoology, University of Cambridge Email author 
  • , Mark D. SpaldingAffiliated withGlobal Marine Team, The Nature Conservancy, Department of Zoology, University of Cambridge
  • , Raymond E. GrizzleAffiliated withDepartment of Biological Sciences, University of New Hampshire
  • , Robert D. BrumbaughAffiliated withGlobal Marine Team, The Nature Conservancy


The oyster habitat in the USA is a valuable resource that has suffered significant declines over the past century. While this loss of habitat is well documented, the loss of associated ecosystem services remains poorly quantified. Meanwhile, ecosystem service recovery has become a major impetus for restoration. Here we propose a model for estimating the volume of water filtered by oyster populations under field conditions and make estimates of the contribution of past (c. 1880–1910) and present (c. 2000–2010) oyster populations to improving water quality in 13 US estuaries. We find that filtration capacity of oysters has declined almost universally (12 of the 13 estuaries examined) by a median of 85 %. Whereas historically, oyster populations achieved full estuary filtration (filtering a volume equivalent or larger than the entire estuary volume within the residence time of the water) in six of the eight estuaries in the Gulf of Mexico during summer months, this is now the case for only one estuary: Apalachicola Bay, Florida. By contrast, while all five estuaries on the North Atlantic coast showed large decreases in filtration capacity, none were achieving full estuary filtration at the time of our c. 1900 historic baseline. This apparent difference from the Gulf of Mexico is explained at least in part by our North Atlantic baseline representing a shifted baseline, as surveyed populations were already much reduced by exploitation in this region.


Crassostrea virginica USA Restoration Estuarine habitat Historical ecology Water quality