Seafood Watch
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Abalone Haliotis spp. ©Monterey Bay Aquarium International – Contained production systems (See separate report on unenclosed sea ranching production) October 27, 2012 Andrea Robertson, Consulting Researcher Disclaimer Seafood Watch® strives to ensure all our Seafood Reports and the recommendations contained therein are accurate and reflect the most up-to-date evidence available at time of publication. All our reports are peer- reviewed for accuracy and completeness by external scientists with expertise in ecology, fisheries science or aquaculture. Scientific review, however, does not constitute an endorsement of the Seafood Watch program or its recommendations on the part of the reviewing scientists. Seafood Watch is solely responsible for the conclusions reached in this report. We always welcome additional or updated data that can be used for the next revision. Seafood Watch and Seafood Reports are made possible through a grant from the David and Lucile Packard Foundation. 2 Final Seafood Recommendation Abalone farmed in land and sea-based enclosures receive a high score of 7.88 out of 10, making this a Best Choice for seafood sustainability. Abalone Haliotis spp. International Contained aquaculture, both land and sea Criterion Score (0–10) Rank Critical? C1 Data 8.61 GREEN N/A C2 Effluent 8.00 GREEN NO C3 Habitat 6.53 YELLOW NO C4 Chemicals 8.00 GREEN NO C5 Feed 10.00 GREEN NO C6 Escapes 4.00 YELLOW NO C7 Disease 4.00 YELLOW NO C8 Source 10.00 GREEN N/A 3.3X Wildlife mortalities -1.00 GREEN NO 6.2X Introduced species escape 0.00 GREEN N/A Total 58.14 Final score 7.27 OVERALL RANKING Final score 7.27 Initial rank GREEN Red criteria 0 Interim rank GREEN Critical criteria? NO Final Rank BEST CHOICE Scoring note – Scores range from zero to ten where zero indicates very poor performance and ten indicates the aquaculture operations have no significant impact. 3 Executive Summary Abalone are single-shelled molluscs native to temperate and tropical oceans around the world. Of the 100 species found worldwide, approximately 15 are grown in aquaculture for human consumption. Abalone available to US consumers are grown domestically (18% of US market) and imported from Mexico (23%), Australia (18%), Chile (16%), and China (13%), among other countries. Data availability is considered excellent due to its wide availability, comprehensive coverage, and multiple peer-reviewed sources. Production systems may use any combination of single-pass flow-through tanks on land and tethered cages or other enclosures in the sea (see separate report on open seabed ranching). These systems discharge effluent into the marine environment, but it is believed that this effluent results in very little detrimental impact. Land-based facilities and tethered sea enclosures have minimal impact on the functionality of surrounding marine habitats and wildlife, including potential abalone predators. Chemical use is minimal, and therefore minimal chemical effluent is released into the marine environment despite the high potential for discharge from sea cages. In the wild, abalone are herbivores, consuming only micro and macroalgae over the course of their lives. Some aquaculture operations supplement algal feed with fishmeal protein, but this practice is relatively rare. In general, cultured abalone do not consume any wild fish, have a small feed footprint, and produce a net gain in edible protein. Algae harvest is generally regulated, and harvested biomass regrows quickly. Abalone feed is therefore considered to be very sustainable. A majority of abalone farms raise locally native species, reducing the risk of environmental harm from potential escapees. Where non-native species are produced, they may or may not already be present in surrounding habitats. In some locations, the potential exists for non- native species to escape and establish themselves in local marine habitats. Historically, the primary disease concern for abalone has been bacterial withering foot syndrome. More recently, a variant of the herpes virus has infected abalone populations in Australia, China, and Taiwan. Due to effluent discharge and flow-through sea enclosures, there is a high risk of pathogen and parasite transmission between wild and cultured populations. However, the global industry is well regulated, with constant monitoring for outbreaks. Overall, abalone farmed in land and sea-based enclosures receive a high score of 7.88 out of 10, making this a best choice for seafood sustainability. 4 Table of Contents Final Seafood Recommendation ..................................................................................................... 2 Executive Summary ......................................................................................................................... 3 Introduction .................................................................................................................................... 5 Scope of the analysis and ensuing recommendation ............................................................ 5 Analysis ........................................................................................................................................... 7 Scoring guide .......................................................................................................................... 7 Criterion 1: Data quality and availability ............................................................................... 7 Criterion 2: Effluents .............................................................................................................. 9 Criterion 3: Habitat .............................................................................................................. 10 Factor 3.3X: Wildlife and predator mortalities .................................................................... 12 Criterion 4: Evidence or Risk of Chemical Use ..................................................................... 13 Criterion 5: Feed .................................................................................................................. 14 Criterion 6: Escapes ............................................................................................................. 16 Factor 6.2X: Escape of unintentionally introduced species................................................. 18 Criterion 7. Disease; pathogen and parasite interactions ................................................... 19 Criterion 8. Source of Stock – independence from wild fisheries ....................................... 21 Overall Recommendation ............................................................................................................. 22 Acknowledgements ....................................................................................................................... 23 References .................................................................................................................................... 23 About Seafood Watch® ................................................................................................................. 27 Guiding Principles ......................................................................................................................... 28 Data points and all scoring calculations........................................................................................ 29 5 Introduction Scope of the analysis and ensuing recommendation This report evaluates the sustainability of abalone commercially available to consumers in the United States. The large majority of this stock is red abalone (Haliotis rufescens), but other abalone may also be found. This report will focus on abalone produced by the five most common sources of abalone in US markets: Mexico, Australia, US, Chile, and China (including Taipei and Hong Kong). In many cases, abalone production methods are similar or identical between countries, but exceptions will also be identified. Abalone farming consists of three phases: hatchery, juvenile, and growout. In the hatchery and juvenile phases, young abalone are grown in land-based raceway and holding tanks. During the growout phase, abalone may be raised using a variety of production systems, including raceway tanks on land and tethered cages or other enclosures at sea. This report addresses the sustainability of all such “enclosed” methods of farming. A separate evaluation is available from Seafood Watch for abalone farmed at sea without the use of enclosures, also known as sea ranching. Species overview Abalone are sessile molluscs found in temperate and tropical intertidal marine waters around the world. They are exclusively herbivores, consuming microalgal films as larvae and macroalgae as juveniles and adults. They are characterized by their single large shell, which has a series of holes along one edge and an iridescent interior. The meat of the abalone is a single large foot that it uses for locomotion, like most marine snails. More than 100 species of abalone exist worldwide, but aquaculture operations tend to focus on approximately 15 species, subspecies, and hybrids (Allsopp et al. 2011). Red abalone (Haliotis rufescens) dominates US markets, as it grows quickly in the temperate waters of the North American west coast and reaches the largest size of any abalone species. The native habitat of red abalone stretches from Oregon to Baja California, from low intertidal waters to a depth of 40 meters (130 feet) (Braje et al. 2009). Humans have been eating abalone for thousands of years.