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Linking Marine Fisheries Species to Biogenic Habitats in New Zealand: a Review and Synthesis of Knowledge

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Linking Marine Fisheries Species to Biogenic Habitats in New Zealand: a Review and Synthesis of Knowledge GEN2015A19 Linking marine fisheries species to biogenic habitats in New Zealand: a review and synthesis of knowledge New Zealand Aquatic Environment and Biodiversity Report No. 130 M.A. Morrison E.G. Jones M. Consalvey K. Berkenbusch ISSN 1179-6480 (online) ISBN 978-0-478-43229-9 (online) May 2014 GEN2015A19 Requests for further copies should be directed to: Publications Logistics Officer Ministry for Primary Industries PO Box 2526 WELLINGTON 6140 Email: [email protected] Telephone: 0800 00 83 33 Facsimile: 04-894 0300 This publication is also available on the Ministry for Primary Industries websites at: http://www.mpi.govt.nz/news-resources/publications.aspx http://fs.fish.govt.nz go to Document library/Research reports © Crown Copyright - Ministry for Primary Industries GEN2015A19 Contents 1 INTRODUCTION .......................................................................................................................... 5 1.1 Objectives ............................................................................................................................... 6 1.2 Scope and limitations of review .............................................................................................. 6 1.3 What is (biogenic) habitat? ..................................................................................................... 7 1.4 Why does (biogenic) habitat matter to fisheries? .................................................................... 9 1.5 Some definitions of habitat/area functions ............................................................................ 11 1.6 The issue of sliding environmental base-lines ...................................................................... 15 2 NEW ZEALAND’S BIOGENIC HABITATS ............................................................................. 16 3 THE COASTAL ZONE ................................................................................................................ 17 3.1 Salt Marsh ............................................................................................................................. 17 3.2 Mangroves (Avicennia marina australasica) ........................................................................ 20 3.3 Seagrass (Zostera capricorni) ............................................................................................... 25 3.4 Macro-algae .......................................................................................................................... 31 3.5 Shellfish (molluscs) biogenic habitats .................................................................................. 45 3.6 Sponges (numerous species) ................................................................................................. 61 3.7 Bryozoan reefs and/or accumulations ................................................................................... 65 3.8 Tubeworms ........................................................................................................................... 76 3.9 Coastal (less than 200 m water depth) gorgonians, red and black corals, hydroids, ascidians, brachiopods, sea-pens, sea-whips and other species ......................................................................... 81 4 BURROWS AS BIOGENIC HABITAT ...................................................................................... 83 4.1 Impact on geotechnical sediment properties ......................................................................... 86 4.2 Impact on geochemical sediment properties ......................................................................... 88 4.3 Burrow irrigation .................................................................................................................. 89 4.4 Geochemistry of burrow environments ................................................................................. 89 4.5 Influence on associated biota ................................................................................................ 9 2 4.6 Burrows as habitats for other species .................................................................................... 93 4.7 Influence on meiofauna ......................................................................................................... 94 4.8 Influence on macrofauna ....................................................................................................... 95 4.9 Influence on aquatic plants ................................................................................................... 97 4.10 Threats to burrows and burrowing organisms ....................................................................... 98 5 THE DEEP SEA (MORE THAN 200 M WATER DEPTH) ....................................................... 98 5.1 New Zealand’s deep-water fish and fisheries ....................................................................... 99 5.2 Corals .................................................................................................................................. 102 GEN2015A19 5.3 Bryozoans ........................................................................................................................... 109 5.4 Sponges ............................................................................................................................... 109 5.5 Tubeworms ......................................................................................................................... 109 6 CASE STUDIES OF BIOGENIC HABITAT LINKS TO FISHERIES..................................... 110 6.1 Blue crabs in the northern Gulf of Mexico ......................................................................... 110 6.2 Sponges and fish on the North-west Australian Continental Shelf ..................................... 112 6.3 Corals and sablefish in Alaska; and a meta-analysis of foundation (biogenic) species ...... 114 7 SELECTED NEW ZEALAND FISHERIES SPECIES – BIOGENIC HABITAT LINKS ....... 116 7.1 Snapper (Pagrus auratus) ................................................................................................... 116 7.2 Tarakihi (Nemodactylus macropterus) ................................................................................ 119 7.3 Blue cod (Parapercis colias) .............................................................................................. 122 8 CONCLUSIONS ......................................................................................................................... 123 8.1 Consider biogenic habitats as a key element of marine ecosystems ................................... 128 8.2 A national (fish-) habitat classification ............................................................................... 129 8.3 Detection and mapping ....................................................................................................... 129 8.4 Habitat modelling and predictive maps............................................................................... 130 8.5 Threats and stressors ........................................................................................................... 130 8.6 Fisheries links – from patch to the fishery scale ................................................................. 130 8.7 The functioning of the biogenic habitats themselves as living organisms .......................... 131 8.8 Integrated marine spatial planning and ecosystem based management .............................. 132 9 ACKNOWLEDGEMENTS ........................................................................................................ 132 REFERENCES ................................................................................................................................... 132 GEN2015A19 EXECUTIVE SUMMARY Morrison, M.A.; Jones, E.; Consalvey, M.; Berkenbusch, K. (2014). Linking marine fisheries species to biogenic habitats in New Zealand: a review and synthesis of knowledge. New Zealand Aquatic Environment and Biodiversity Report No. 130. 156 p. Fisheries research and management has traditionally been focussed on the fish populations, while the habitats and environments which underpin their production have been largely ignored. This situation is changing, with an increasing awareness that habitats are important and can be degraded through human activities, both marine and land-based. While the wider field of marine ecology has been researching such fish-habitat themes for a number of decades, the species worked on are often small, site-attached, and relatively short-lived; while fisheries species tend to be larger bodied, and operate over much larger spatial and temporal scales. Given this, quantitatively linking fisheries species to habitats is a challenge, and an active field of research. One type of habitat that appears to be especially important for many demersal species are those referred to as ‘biogenic’ habitats. These biogenic habitats are formed by plants and animals, and occur from the inter-tidal out to the deep sea. Well known biogenic habitats include salt marshes, mangrove forests, seagrass meadows, kelp forests, bryozoan fields, and shellfish beds. For the purposes of this review, biogenic habitats are defined as a) those living species that form emergent three-dimensional structure, that separate areas in which they occur from surrounding lower vertical dimension seafloor habitats and b) non-living structure generated by living organisms, such as infaunal tubes and burrows. A sub-set of these habitats are biogenic “reefs”, which
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