Expect the unexpected: place-based protections can lead to unforeseen benefits

  • Published source details Flitcroft R.L., Bottom D.L., Haberman K.L., Bierly K.F., Jones K.K., Simenstad C.A., Gray A., Ellingson K.S., Baumgartner E., Cornwell T.J. & Campbell L.A. (2016) Expect the unexpected: place-based protections can lead to unforeseen benefits. Aquatic Conservation: Marine and Freshwater Ecosystems, 26, 39-59.


This study is summarised as evidence for the following.

Action Category

Facilitate tidal exchange to restore/create brackish/salt marshes from other land uses

Action Link
Marsh and Swamp Conservation
  1. Facilitate tidal exchange to restore/create brackish/salt marshes from other land uses

    A site comparison study of four brackish marshes in an estuary in Oregon, USA (Flitcroft et al. 2016) reported that after removing levees to restore tidal exchange, the plant community became more similar to that of a nearby natural marsh – but remained significantly different after >30 years. In all three restored marshes, freshwater pasture grasses were gradually replaced by native salt-tolerant species such as pickleweed Salicornia virginica and saltgrass Distichlis spicata (data not reported). However, in a marsh where tidal exchange had been restored for the longest time (>30 years), the overall plant community composition remained significantly different from the natural marsh (data not reported). This restored marsh lacked some “diagnostic” brackish marsh species, such as Baltic rush Juncus balticus and black bent Agrostis alba. Methods: Vegetation was surveyed in four brackish marshes within the Salmon River estuary (years and survey methods not reported; salinity obtained from Gray et al. 2002). In three marshes, tidal influx had been restored. Levees that kept these sites as freshwater pasture were removed in 1978, 1987 or 1996. The other site was a natural marsh, where tidal influx had never been modified.

    Additional Reference: Gray A., Simenstad C.A., Bottom D.L & Cornwell T.J. (2002) Contrasting functional performance of juvenile salmon in recovering wetlands of the Salmon River estuary, Oregon USA. Restoration Ecology, 10, 514–526.

    (Summarised by: Nigel Taylor)

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