Scaling restoration actions in the marine environment to meet quantitative targets of enhanced ecosystem services

Expectations of ecological and fisheries benefits of habitat restoration are commonly used to justify its high financial cost; however, few empirical studies that rigorously test these expectations exist. Here, we describe the results of a study designed to quantify the effects of restoring oyster reefs in marsh tidal creeks on the mobile macrofauna. We used a before/after control/impact (BACI) design in which fishes and crustaceans within 6 tidal creeks were sampled 7 × before and 14 × after the addition of live oyster reefs to 3 of the tidal creeks. We detected no significant effects of the addition of oyster reefs on the overall fish or crustacean assemblages within the tidal creeks, and a weak positive effect on the abundance of demersal fishes. These results challenge current predictions that restoration of oyster reefs will result in an increase in mobile fauna. Our findings of no increase in mobile fauna may have resulted from the functional redundancy of a nearby biogenic habitat because reefs were placed in tidal creeks that were surrounded by dense salt marsh. We conclude that a positive correlation between mobile fauna and oyster habitat is not automatic, and that the role of the surrounding landscape is important in predicting the response of transient fish and crustaceans to oyster reef restoration.

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Can habitat restoration be redundant? Response of mobile fishes and crustaceans to oyster reef restoration in marsh tidal creeks

Geraldi

Powers²,

Heck³

et al. 2009

“…Assumptions are often needed because of the lack of area-specific data, large uncertainty in relevant biological parameters and/or the lack of clear consensus in the literature on key issues (Peterson et al 2003a). Injury estimates and restoration scaling are highly sensitive to life history data for individual species.…”

Section: Discussionmentioning

confidence: 99%

“…For example, unlike restoration opportunities for many species of marine fishes and invertebrates, it is not practical, nor in many cases possible, to replace dead, injured or missing birds directly through captive breeding programs. Although the creation of some types of new habitat is possible and may be an effective mechanism for enhancing fish and invertebrate populations (Peterson et al 2003a, in this Theme Section), creating shoreline for coastal bird species would typically be enormously expensive. In contrast to many marine fish and invertebrate species, however, considerable efforts to conserve bird populations have been conducted for decades by government and private entities.…”

Section: Introductionmentioning

confidence: 99%

Scaling restoration to achieve quantitative enhancement of loon, seaduck, and other seabird populations

Sperduto

Powers²,

Donlan³

2003

The 1996 'North Cape' oil spill along the Rhode Island coast led to the deaths of at least 2292 birds, resulting in an estimated 6275 bird-years lost (adjusted by expected longevity and productivity). We synthesize information on bird population dynamics to develop an appropriate restoration strategy. Marine birds (seaducks, loons, grebes) with natural recovery periods estimated to exceed 1 yr accounted for 87% of the total bird-years lost. Marine birds (gulls, cormorants, alcids, gannets) with recovery estimated to be less than a year accounted for 10% of injuries. Common loons Gavia immer and common eiders Somateria mollissima were selected as targets for restoration because of regional concern over their population status and the magnitude of lost bird-years. Three restoration options were evaluated for loons: nest site protection; nest site enhancement; and public education/outreach. Nest site enhancement opportunities were limited and benefits from public education/outreach efforts were uncertain. Nest site protection was preferred for both loons and eiders because nest site availability and/or quality currently limit(s) productivity. This option assumes that preventing future productivity loss compensates for productivity loss that resulted from the 'North Cape' oil spill. This assumption is supported by regional productivity estimates for the 2 target species, is consistent with scientific literature, and represents the consensus of expert opinions. Based on a series of scaling calculations, protection of 25 nest sites for a 100 yr period is expected to balance the loss of 2920 loon-years. Protection of 315 eider nest sites over a 100 yr period would replace 2605 bird-years lost (remaining marine bird injury). Calculations adjust future production credit through economic discounting of 3% yr

“…Compensatory restoration is sometimes required to elevate lost ecosystem services by converting a less valued habitat into a more valued one (Peterson et al 2003). Salt marshes have been preferentially restored in recognition of their high primary productivity and contributions to faunal abundance (Peterson et al 2008a).…”

Section: Introductionmentioning

confidence: 99%

Evaluating estuarine habitats using secondary production as a proxy for food web support

Wong

Peterson

Piehler

2011

Self Cite

The management, restoration, and conservation of estuarine habitats would benefit from knowledge of habitat-specific functions that reflect important ecosystem services. Secondary production may provide a comprehensive metric of food web support because it synthesizes contributions of local primary production, food subsidies from other habitats, and the protective influences of habitat structure. Despite widespread perceptions of how habitats compare in food web contribution, few methodologically comparable studies on secondary production across multiple estuarine habitats exist. At field sites in North Carolina, USA, annual secondary production was estimated for macrobenthic infaunal and epifaunal communities in salt marshes, seagrass meadows, oyster reefs, intertidal and subtidal flats, and on shoreline stabilization structures. Habitats with hard emergent or biogenic structure generally exhibited higher secondary production than habitats lacking structure. Oyster reef had the highest secondary production, ranging from 467.3 to 853.7 g ash free dry mass (AFDM) m −2 yr −1, while shoreline stabilization structures ranked high because of dense epifaunal communities. Estimates of secondary production suggest ranking of natural habitats as oyster reef > salt marsh > seagrass > intertidal flat and subtidal flat. Undesirable impacts of shoreline stabilization structures on adjacent habitats made their inclusion in this ranking of food web support by habitat difficult. The importance of suspension feeders on oyster reefs, shoreline stabilization structures, and in some marshes suggests that secondary production patterns are partly influenced by external subsidies facilitated by support from habitat structure. Consequently, estuarine rehabilitation should include structural habitat elements that will contribute to ecosystem production at higher trophic levels. Without such habitat restoration, the fate of estuaries in the USA affected by anthropogenic stressors may be loss of habitat diversity and prevalence of low-trophic-supporting habitats.