Abstract

Restoring wetlands to improve habitats for birds has become an important conservation tool as many wetlands have deteriorated and wetland bird populations declined. To what extent such restorations are effective is not well known because surveys usually either lack data before the restoration or means of correcting for background population trends. We identified wetland restorations made in agricultural landscapes in Sweden and retrieved all available Before-After survey data of breeding birds. From the resulting heterogeneous surveys, we quantified the effectiveness of restorations for eight bird groups comprising 72 bird species from 30 wetlands. We used national survey data to correct for background population trends. We estimated that island breeder populations have increased by between 62 % and 315 % (95 % confidence intervals) following restorations. Deep water foragers, shallow water foragers and short meadow breeders also mainly increased following restoration. The direction of effect was uncertain for tall meadow breeders, reed breeders and predators. Shrubland breeder populations declined between-55 % and-4 % following restorations. While restoration measures seemed to generally benefit about half of the breeding wetland bird community, estimated species-and site-specific re-sponses varied greatly and were associated with large uncertainty. Such heterogeneity in responses can arise due to biotic and abiotic interactions, varying management actions and survey methods between wetlands. Thus, to improve the effectiveness of future wetland restorations, funding bodies and environmental agencies should require standardised Before-After bird surveys at both restored and non-restored reference sites. Such improved survey designs would facilitate the development of more efficient restoration efforts.

Keywords

Management; Aves; BACI; Eutrophic lakes; Wetland overgrowth; Freshwater ecosystem

Published in

Biological Conservation
2022, Volume: 273, article number: 109676
Publisher: ELSEVIER SCI LTD

SLU Authors

• Kacergyté, Ineta

  • Department of Ecology, Swedish University of Agricultural Sciences
    

• Pärt, Tomas

  • Department of Ecology, Swedish University of Agricultural Sciences
    

• Berg, Åke

  • Department of Urban and Rural Development, Swedish University of Agricultural Sciences
    

• Arlt, Debora

  • Department of Ecology, Swedish University of Agricultural Sciences
    
  • SLU Swedish Species Information Centre, Swedish University of Agricultural Sciences
    

• Knape, Jonas

  • Department of Ecology, Swedish University of Agricultural Sciences
    

Associated SLU-program

SLU Swedish Biodiversity Centre


Sustainable Development Goals

Ensure availability and sustainable management of water and sanitation for all
Protect, restore and promote sustainable use of terrestrial ecosystems, sustainably manage forests, combat desertification, and halt and reverse land degradation and halt biodiversity loss


UKÄ Subject classification

Environmental Sciences related to Agriculture and Land-use
Ecology


Publication identifier

DOI: https://doi.org/10.1016/j.biocon.2022.109676

Permanent link to this page (URI)

https://res.slu.se/id/publ/119027