Mitigating against the loss of species by adding artificial intertidal pools to existing seawalls

Abstract

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 497:119-129 (2014) - DOI: https://doi.org/10.3354/meps10596 Mitigating against the loss of species by adding artificial intertidal pools to existing seawalls Mark Anthony Browne1,2,*, M. G. Chapman1 1Centre for Research on Ecological Impacts of Coastal Cities, School of Biological Sciences, University of Sydney, New South Wales 2006, Australia 2National Center for Ecological Analysis and Synthesis, University of California, Santa Barbara, 735 State Street, Suite 300, Santa Barbara, California 93101-3351, USA *Corresponding author: browne@nceas.ucsb.edu ABSTRACT: Over 80% of the money allocated to protect coastlines from climatic change is spent building new seawalls or increasing the stability, height and length of existing seawalls. Although this protects important infrastructure, it has serious consequences for intertidal biodiversity, because walls are built and maintained according to engineering and financial criteria, despite the fact that they are known to adversely affect intertidal biodiversity. We tested the predictability and reliability of adding pots, designed to simulate rockpools, to seawalls as an artificial habitat to mitigate against loss of intertidal species. Two sizes of concrete pots were attached at mid- and highshore tidal levels to sandstone seawalls at 2 locations in Sydney Harbour, Australia. After 7 mo, pots increased intertidal biodiversity on the seawalls by adding additional species. They also supported greater covers and densities of algae and many invertebrates compared with established assemblages on the seawalls. The size of the pot, its height on the wall and its location affected the assemblages that developed, with greater abundances and diversity of organisms in shallower pots and those at midshore levels. Although there were slight differences between locations for some taxa, these results show an easy cost-effective method that authorities can use to try to mitigate the adverse effects on intertidal assemblages of armouring shorelines with featureless, vertical walls. KEY WORDS: Biodiversity · Climatic change · Coastal squeeze · Surrogate habitat · Seawall · Succession · Urbanization Full text in pdf format PreviousNextCite this article as: Browne MA, Chapman MG (2014) Mitigating against the loss of species by adding artificial intertidal pools to existing seawalls. Mar Ecol Prog Ser 497:119-129. https://doi.org/10.3354/meps10596 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 497. Online publication date: February 05, 2014 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2014 Inter-Research.