Cryptic invertebrates on subtidal rocky reefs vary with microhabitat structure and protection from fishing

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 481:93-104 (2013) - DOI: https://doi.org/10.3354/meps10263 Cryptic invertebrates on subtidal rocky reefs vary with microhabitat structure and protection from fishing Timothy J. Alexander* Institute of Marine and Antarctic Studies, University of Tasmania, GPO Box 252, Private Bag 49, Hobart, Tasmania 7001, Australia *Email: tjalexander001@gmail.com ABSTRACT: The deployment of flat concrete blocks on subtidal rocky reefs can replicate natural reef microhabitats and provides a means for standardized sampling of cryptic invertebrates. The shape of the cavity beneath the block is related to reef topography and may influence the invertebrate community by affecting the amount of space for cryptic fauna to colonise and influencing the effectiveness of their predator-defence mechanisms. To determine the effect of sub-block reef structure and different levels of external predators on cryptic molluscs and echinoderms, I deployed concrete blocks at locations inside and outside the Maria Island marine reserve in eastern Tasmania, Australia. Relationships between sub-block reef structure and the cryptic invertebrate assemblage were evident between locations, whereas only a small but significant proportion of variation of assemblages between blocks within location was explained by reef surface area. No clear association with external predation pressure was evident in multivariate analyses of variation in assemblage structure. Juvenile abalone Haliotis rubra were not influenced by microhabitat structure but were significantly less abundant at protected locations, the only species to exhibit such a response. This result follows a decline of emergent adult abalone in the marine reserve and raises the possibility of recruitment failure of abalone at some fully protected locations in the longer term. KEY WORDS: Cryptic species · Marine reserve · Abalone · Boulders · Echinoderms · Molluscs Full text in pdf format PreviousNextCite this article as: Alexander TJ (2013) Cryptic invertebrates on subtidal rocky reefs vary with microhabitat structure and protection from fishing. Mar Ecol Prog Ser 481:93-104. https://doi.org/10.3354/meps10263 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 481. Online publication date: May 07, 2013 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2013 Inter-Research.