Faunal communities are invariant to fragmentation in experimental seagrass landscapes

Department of Biological Sciences, Virginia Institute of Marine Science, The College of William & Mary, Gloucester Point, VA, USA
Marine Resources Program, Oregon Department of Fish & Wildlife, Newport, OR, USA
DOI
10.7287/peerj.preprints.1823v2
Subject Areas
Ecology, Marine Biology
Keywords
epifauna, eelgrass, habitat loss, mesopredators, estuaries
Copyright
© 2016 Lefcheck et al.
Licence
This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, reproduction and adaptation in any medium and for any purpose provided that it is properly attributed. For attribution, the original author(s), title, publication source (PeerJ Preprints) and either DOI or URL of the article must be cited.
Cite this article
Lefcheck JS, Marion SR, Lombana AV, Orth RJ. 2016. Faunal communities are invariant to fragmentation in experimental seagrass landscapes. PeerJ Preprints 4:e1823v2

Abstract

Human-driven habitat fragmentation is cited as one of the most pressing threats facing many coastal ecosystems today. Many experiments have explored the consequences of fragmentation on fauna in one foundational habitat, seagrass beds, but have either surveyed along a gradient of existing patchiness, used artificial materials to mimic a natural bed, or sampled over short timescales. Here, we describe faunal responses to constructed fragmented landscapes varying from 4-400 m2 in two transplant garden experiments incorporating live eelgrass (Zostera marina L.). In experiments replicated within two subestuaries of the Chesapeake Bay, USA across multiple seasons and non-consecutive years, we comprehensively censused mesopredators and epifaunal communities using complementary quantitative methods. We found that community properties, including abundance, species richness, Simpson and functional diversity, and composition were generally unaffected by the number of patches and the size of the landscape, or the intensity of sampling. Additionally, an index of competition based on species co-occurrences revealed no trends with increasing patch size, contrary to theoretical predictions. We extend conclusions concerning the invariance of animal communities to habitat fragmentation from small-scale observational surveys and artificial experiments to experiments conducted with actual living plants and at more realistic scales. Our findings are likely a consequence of the rapid life histories and high mobility of the organisms common to eelgrass beds, and have implications for both conservation and restoration, suggesting that even small patches can rapidly promote abundant and diverse faunal communities.

Author Comment

Minor formatting and grammatical changes based on referee comments, concurrent with submission of the revised copy to a peer-reviewed journal.

Supplemental Information

Supplement 2 - Functional Traits

DOI: 10.7287/peerj.preprints.1823v2/supp-2