DOCSLIB.ORG

Drivers of Spatial and Temporal Movement Patterns of Acanthopagrus Butcheri Through an Estuarine Surge Barrier

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Drivers of Spatial and Temporal Movement Patterns of Acanthopagrus Butcheri Through an Estuarine Surge Barrier Drivers of spatial and temporal movement patterns of Acanthopagrus butcheri through an estuarine surge barrier Submitted by Richelle McCormack This thesis is presented for the degree of Bachelor of Science Honours. College of Science, Health, Engineering and Education, Murdoch University 2019 Declaration I declare this thesis is my own account of my research and contains as its main content work which has not been previously submitted for a degree at any tertiary education institution. Richelle McCormack ii Acknowledgements I would like to extend a very special thank you to all my supervisors. Dr Stephen Beatty for all his expertise and knowledge on freshwater ecosystems and statistics; Dr James Tweedley for his expert knowledge on the Vasse-Wonnerup Estuary and thorough editing of all my work; and Dr Alan Cottingham for his expert knowledge on all things Black Bream, south-west Australian estuaries and for teaching me the ropes on catch and release and PIT tagging of fish in the middle of the night on board a little rickety dinghy in Busselton. I feel so lucky to have had three amazing academics by my side throughout my Honours experience, who have worked collaboratively to make this as much an enjoyable and educational experience as Honours can be. They all dedicated so much time and effort in covering my drafts in red ink and meeting with me for countless hours, and I am so grateful for their dedication. My supervisors also introduced me to a wealth of professionals who aided in my research. Thank you to Tom Ryan for his technical assistance and initial set up of the PIT antenna system. I extend a lot of gratitude to GeoCatch and Department of Water and Environmental Regulation (DWER) and the Water Corporation for the hydrological data and Bureau of Meteorology (BoM) for the environmental data without which this project would not have been possible. The fieldwork components of this project were also funded by DWER (IRMA 17379) with support from GeoCatch, so another massive thanks for that. My sincere gratitude goes to Karl Pomorin Karltek whose technology in conjunction with the PIT system made tracking fish from the comfort of my lounge room possible. Thank you to the Busselton and Molloy Senior high schools for assisting in the collection of in situ data, and the wider Busselton community for showing a genuine interest in the health and management of the Vasse-Wonnerup Estuary. The study was conducted under Murdoch University Animal Ethics Committee permit RW2793/15 and Department of Primary Industries and Regional Development (Fisheries) Exemption 2902. I acknowledge the Noongar people who are the Traditional Custodians of the land on which my research took place. iii To the great friends I’ve made through the last year and a half that have provided moral support, motivation and just great banter- Elysia Tingey and Georgina Stagg, it’s been comforting knowing we’ve all been in the same boat, so thank you so much! Last but definitely not least, a huge thank you and deepest appreciation and love to my incredible partner Tyson Addicoat who has supported me in every way throughout this project. His emotional support, positivity and ability to put up with my sleep deprivation and stress induced moods in particular has been nothing short of heroic. To all my friends and family that I have had to cancel plans on and have not seen for a while, thank you for your understanding, and I cannot wait to make up for lost time in seeing you all now that my studies are complete... until next time! iv Abstract Coastal and estuarine environments are popular sites for human settlement, yet they are among the most vulnerable to changing climate and extreme weather events such as rising sea level and storm surges. Storm surge barriers have been installed in numerous estuaries around the world to mitigate flooding risk. However, these structures have numerous deleterious impacts on ecological connectivity by restricting flow and fragmenting habitats, thus preventing fishes from accessing preferred spawning, nursery and feeding areas. Despite the ecological impact of estuarine surge barriers being well recognised, few studies have investigated their impact on obligate estuarine fishes; particularly at the individual level. The highly degraded Vasse-Wonnerup Estuary in south-western Australia has suffered regular mass fish kills, and fish gates were installed on the storm surge barriers to enable two-way fish passage in times of poor water quality. However, the majority of recent fish kills have occurred immediately upstream of the Vasse Surge Barrier (VSB) suggesting the gates have been ineffective in facilitating movement. The sparid Acanthopagrus butcheri has been particularly impacted by these fish kills. Due to its large body size, life-history characteristics and socio-economic importance in southern Australia, this obligate estuarine species is ideal to investigate how fish passage through the VSB may be influenced by prevailing environmental conditions. The fine-scale movement patterns of passive integrated transponder (PIT) tagged A. butcheri were monitored through the VSB using a custom designed system between 20th March 2017 and 31st May 2018. Passage data were analysed together with a suite of hydrological and environmental variables using generalised additive mixed models to determine the drivers of fish approaches (i.e. those detected at the downstream site of the fish gate without subsequently passing through) and the daily and hourly upstream and downstream passages through the fish gate. Daily approaches of A. butcheri to the VSB were typically greatest during September-December and April-May. As the species is known to spawn in July-October in the system, the increase in PIT detections in spring may have been partially associated v with an adult upstream migration. However, the key spawning site for the species is known to occur in another region of the system (i.e. the ‘Deadwater’ region) rather than habitats upstream of the VSB. This fact, along with the increase in detections at the VSB that occurred during April-May outside of the spawning period, suggests that the peaks in detections at the VSB may have been attributed to high localised migration, rather than representing spawning activity. Hourly upstream and downstream passages through the fish gate were nocturnal and crepuscular, respectively. Downstream passages were also associated with declines in dissolved oxygen concentrations in the upstream habitats; suggesting that A. butcheri was seeking to escape poor water quality. However, the hourly and daily upstream and downstream passages of A. butcheri were also strongly associated with times of minimal flow velocity within the fish gate that occurred when water levels equalised on the upstream and downstream sides of the VSB. Therefore, while the species appeared to be avoiding poor water quality by passing through the fish gate, it appeared this could only occur during certain hydrological conditions. This likely limited its ability to freely escape from times of poor water quality, thus explaining the periodic fish kills that occur mostly upstream of the VSB. These findings have clear implications for the management of the VSB and also instream barriers in other systems that house A. butcheri. A key recommendation for the future management of the VSB is to automate the fish gate operation so it opens during times of upstream and downstream water equalisation. This would maximise fish passage opportunities and simultaneously prevent salt-water intrusion upstream prevents stratification and associated hypoxia and toxic algal blooms. Given the projected increase in sea level rise and decrease in rainfall in south- western Australia, and indeed many parts of the world, associated with climate change, the construction of storm surge barriers is becoming more prevalent. This study highlights the need to understand the movement patterns and life-history requirements of resident estuarine species to maintain connectivity to critical habitats. vi Contents Acknowledgements ..................................................................................................... iii Abstract ........................................................................................................................ v 1. Introduction ............................................................................................................. 1 1.1. Estuaries and their fish faunas ....................................................................................... 1 1.2. Threats to estuaries ....................................................................................................... 3 1.3. Instream barriers ........................................................................................................... 5 1.4. South-western Australian estuaries ............................................................................... 7 1.5. Acanthopagrus butcheri................................................................................................. 8 1.6. Aims and hypotheses ..................................................................................................... 9 2. Materials and Methods .......................................................................................... 10 2.1. Study site......................................................................................................................10 2.2. Surge barrier and fish fauna ..........................................................................................13
Load more

Recommended publications
  • Disease List for Aquaculture Health Certificate
    Quarantine Standard for Designated Species of Imported/Exported Aquatic Animals [Attached Table] 4. Listed Diseases & Quarantine Standard for Designated Species Listed disease designated species standard Common name Disease Pathogen 1. Epizootic haematopoietic Epizootic Perca fluviatilis Redfin perch necrosis(EHN) haematopoietic Oncorhynchus mykiss Rainbow trout necrosis virus(EHNV) Macquaria australasica Macquarie perch Bidyanus bidyanus Silver perch Gambusia affinis Mosquito fish Galaxias olidus Mountain galaxias Negative Maccullochella peelii Murray cod Salmo salar Atlantic salmon Ameirus melas Black bullhead Esox lucius Pike 2. Spring viraemia of Spring viraemia of Cyprinus carpio Common carp carp, (SVC) carp virus(SVCV) Grass carp, Ctenopharyngodon idella white amur Hypophthalmichthys molitrix Silver carp Hypophthalmichthys nobilis Bighead carp Carassius carassius Crucian carp Carassius auratus Goldfish Tinca tinca Tench Sheatfish, Silurus glanis European catfish, wels Negative Leuciscus idus Orfe Rutilus rutilus Roach Danio rerio Zebrafish Esox lucius Northern pike Poecilia reticulata Guppy Lepomis gibbosus Pumpkinseed Oncorhynchus mykiss Rainbow trout Abramis brama Freshwater bream Notemigonus cysoleucas Golden shiner 3.Viral haemorrhagic Viral haemorrhagic Oncorhynchus spp. Pacific salmon septicaemia(VHS) septicaemia Oncorhynchus mykiss Rainbow trout virus(VHSV) Gadus macrocephalus Pacific cod Aulorhynchus flavidus Tubesnout Cymatogaster aggregata Shiner perch Ammodytes hexapterus Pacific sandlance Merluccius productus Pacific
    [Show full text]
  • Oyster Farms Are the Main Spawning Grounds of the Black Sea Bream Acanthopagrus Schlegelii in Hiroshima Bay, Japan
    Oyster farms are the main spawning grounds of the black sea bream Acanthopagrus schlegelii in Hiroshima Bay, Japan Kentaro Kawai, Hiroki Fujita, Gustavo Sanchez and Tetsuya Umino Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi Hiroshima, Hiroshima, Japan ABSTRACT Understanding the anthropogenic impact of oyster farms is essential for the management and conservation of marine fishes. In Japan, Hiroshima Bay is the region with the most intense oyster farming and thus suitable to study the impact of these farms. Here, we surveyed spherical planktonic eggs of the black sea bream Acanthopagrus schlegelii, one of the most abundant fish in the Bay. Our survey was performed at fourteen stations which included places with oyster farms and historical spawning grounds. We found the highest egg densities in four stations, one with historical spawning aggregations and three with major oyster farms. Besides, surveys at the innermost part of Hiroshima Bay, where two major rivers discharge, showed a low density of eggs indicating that black sea bream avoids spawning in low salinity areas. Our study suggests that oyster farms benefit spawners of black sea bream by providing more food sources than historical spawning grounds for efficient spawning. Yet, whether oyster farms represent a full advantage for the species remains unclear, particularly because they are known to host jellyfishes that prey on eggs and limit water flow that can influence the survival of fish eggs. Subjects Agricultural Science, Aquaculture, Fisheries and Fish Science, Ecology, Marine Biology, Submitted 8 February 2021 Accepted 26 April 2021 Zoology Published 1 June 2021 Keywords Shellfish aquaculture, Fish spawning, Sparid, Anthropogenic impact, Fish eggs Corresponding author Tetsuya Umino, INTRODUCTION [email protected] Hiroshima Bay is an enclosed bay in the western Seto Inland Sea of Japan with an average Academic editor seabed depth of 25.6 m.
    [Show full text]
  • BARRAMUNDI Barramundi (Lates Calcarifer) Are Native to the Indo-Paci C Region Where They Can Be Found in Both Freshwater, Brackish Water, and Saltwater Environments
    Assessment FARMED BARRAMUNDI Barramundi (Lates calcarifer) are native to the Indo-Pacic region where they can be found in both freshwater, brackish water, and saltwater environments. Sea Port sources their farmed Barramundi from Vietnam, China, and Taiwan. Barramundi are a good species for farming because they are very tolerant of many production challenges, such as temperature changes and crowding. Sea Port sources from farms that produce from primarily earthen ponds. These ponds make is easier for farmers to monitor and reduce pollution discharges, escapees, diseases, and feed inputs when compared to farmers using open pen/cage production methods in lakes or marine habitats. GO BLUE! SEAFOOD SUSTAINABILITY SPECTRUM ENVIRONMENTAL IMPACT LEVEL: MODERATE ACTIONS THAT SEA PORT IS UNDERTAKING Because Barramundi require a lot of protein in their diet, they have Sea Port is promoting the occasional consumption of farmed historically been fed pellets that contain wild sh as an ingredient. Barramundi based on our belief that a wide variety of farmed seafood However, advances in feed formulations that substitute various grain holds the best promise to relieve pressure on our wild sheries while meals and animal byproducts for shmeal have greatly reduced the increasing the availability of high quality and healthy seafood. amount of marine feed inputs to around 10-15%. Barramundi farming Barramundi certainly adds to this variety and we foresee progress in shares the same universal environmental risks associated with most the development of new feed formulas to further reduce the content nsh pond/pen/cage aquaculture in terms of trying to minimize of marine resources. diseases and its spread, chemical/antibiotic use, pollution, escapees, and disruption to local fauna, ora, and to the hydrology of the local habitats We created the sustainability assessments for each of our seafood in which production is occurring.
    [Show full text]
  • First Report of Megalocytivirus (Iridoviridae) in Grouper Culture in Sabah, Malaysia
    Int.J.Curr.Microbiol.App.Sci (2014) 3(3): 896-909 ISSN: 2319-7706 Volume 3 Number 3 (2014) pp. 896-909 http://www.ijcmas.com Original Research Article First report of Megalocytivirus (Iridoviridae) in grouper culture in Sabah, Malaysia Asrazitah Abd Razak1, Julian Ransangan1* and Ahemad Sade2 1Microbiology and Fish Disease Laboratory, Borneo Marine Research Institute, Universiti Malaysia Sabah, Jalan UMS, 88400, Kota Kinabalu, Sabah, Malaysia 2Fisheries Department Sabah, Wisma Pertanian, Jalan Tasek, 88628 Kota Kinabalu, Sabah, Malaysia *Corresponding author A B S T R A C T Groupers are popular aquaculture species in Sabah, Malaysia. However, its aquaculture production is often limited by disease outbreaks. Although many diseases are known to affect groupers, iridovirus infection is a major concern because it causes high mortality within a short period of time. Recently, a disease resembled to iridovirus occurred and caused heavy losses to grouper aquaculture in K e y w o r d s Sabah. This has prompted us to conduct a study with the aim to determine if iridovirus present in the culture groupers. In this study, we examined 212 fish Grouper; specimens, which represented all the major culture grouper species in Malaysia. Megalo- The examination was carried out using single- and nested-PCR methods and cytivirus; followed by DNA sequencing. Two genes (major capsid protein and ATPase) were ISKNV; targeted for the PCR amplification and DNA sequencing. The finding showed nested-PCR; 15.6% (33/212) of the grouper specimens were severely infected by iridovirus. Sabah; Meanwhile, 17.4% of the specimens exhibited latent infection or asymptomatic Malaysia carriers.
    [Show full text]
  • Restocking the Blackwood River Estuary with the Black Bream Acanthopagrus Butcheri Project No. 2000/180
    Restocking the Blackwood River Estuary with the Black Bream Acanthopagrus butcheri Jenkins, G.I., French, D.J.W., Potter, I.C., de Lestang, S., Hall, N.G., Partridge, G.J., Hesp, S.A. and Sarre, G.A. Project No. 2000/180 Fisheries Research and Development Corporation Report FRDC Project 2000/180 Restocking the Blackwood River Estuary with the Black Bream Acanthopagrus butcheri. Jenkins, G.I. # French, D.J.W.* Potter, I.C. * de Lestang, S.* Hall, N.* Partridge, G.J. # Hesp, S.A. * Sarre, G.A. * June 2006 #Aquaculture Development Unit WA Maritime Training Centre, Challenger TAFE 1 Fleet Street, Fremantle, Western Australia, 6160 *Centre for Fish and Fisheries Research School of Biological Sciences and Biotechnology Murdoch University Murdoch, Western Australia 6150 This work is copyright. Except as permitted under the Copyright Act 1968 (Cth), no part of this publication may be reproduced by any process, electronic or otherwise, without the specific written permission of the copyright owners. Neither may information be stored electronically in any form whatsoever without such permission. June 2006 ISBN: 86905-8932 1 TABLE OF CONTENTS TABLE OF CONTENTS ..............................................................................................................................2 OBJECTIVES................................................................................................................................................3 NON-TECHNICAL SUMMARY.................................................................................................................4
    [Show full text]
  • Barramundi Fillets
    Barramundi Fillets >> MILD, SWEET FLAVOR >> GREAT SOURCE OF OMEGA-3 >> PROVIDES AFFORDABLE MENU VERSATILITY Barramundi Fillets A unique yet affordable gourmet fish, Barramundi is prized for its succulent white flesh, mildly sweet flavor and delicate texture, making it an ideal addition to most any seafood recipe. Also called Asian Sea Bass, Barramundi is a great source of Omega-3 and has remarkable menu versatility. Trident’s deep-skinned fillets are carefully portioned for consistent sizing, and they offer a beautiful and distinctive presentation whether steamed, baked, grilled or fried. Features & Benefits >> UNIQUE MENU ITEM Provides menu differentiation with mainstream appeal >> A GOOD SOURCE OF OMEGA-3 Comparable to wild salmon HANDLING INSTRUCTIONS >> DEEP SKINNED Keep frozen until ready to thaw. Ensures a mild flavor and white fillet color when cooked Thawing Instructions: Remove all packaging. Place on tray or plate. Cover with a plastic wrap or wax paper and thaw in refrigerator for 16 – 24 hours. Keep thawed product refrigerated and use within 2 – 3 days. Species Information COOKING INSTRUCTIONS Barramundi is a buttery tasting whitefish with delicate, Remove all packaging. flaky texture and naturally high Omega-3 content. Trident Oven temperatures vary. Cook to an internal temperature of 145°F. Barramundi are farm-raised in ocean pens by suppliers From thawed, allow 10 minutes of cooking time per inch of held to the strictest environmental standards, ensuring thickness at 350°F until fish flakes easily when tested with a fork. consistent clean flavor and the highest quality. From frozen, double the cooking time. Fish is best when the flesh has just turned opaque and is still moist throughout.
    [Show full text]
  • Biology, Stock Status and Management Summaries for Selected Fish Species in South-Western Australia
    Fisheries Research Report No. 242, 2013 Biology, stock status and management summaries for selected fish species in south-western Australia Claire B. Smallwood, S. Alex Hesp and Lynnath E. Beckley Fisheries Research Division Western Australian Fisheries and Marine Research Laboratories PO Box 20 NORTH BEACH, Western Australia 6920 Correct citation: Smallwood, C. B.; Hesp, S. A.; and Beckley, L. E. 2013. Biology, stock status and management summaries for selected fish species in south-western Australia. Fisheries Research Report No. 242. Department of Fisheries, Western Australia. 180pp. Disclaimer The views and opinions expressed in this publication are those of the authors and do not necessarily reflect those of the Department of Fisheries Western Australia. While reasonable efforts have been made to ensure that the contents of this publication are factually correct, the Department of Fisheries Western Australia does not accept responsibility for the accuracy or completeness of the contents, and shall not be liable for any loss or damage that may be occasioned directly or indirectly through the use of, or reliance on, the contents of this publication. Fish illustrations Illustrations © R. Swainston / www.anima.net.au We dedicate this guide to the memory of our friend and colleague, Ben Chuwen Department of Fisheries 3rd floor SGIO Atrium 168 – 170 St Georges Terrace PERTH WA 6000 Telephone: (08) 9482 7333 Facsimile: (08) 9482 7389 Website: www.fish.wa.gov.au ABN: 55 689 794 771 Published by Department of Fisheries, Perth, Western Australia. Fisheries Research Report No. 242, March 2013. ISSN: 1035 - 4549 ISBN: 978-1-921845-56-7 ii Fisheries Research Report No.242, 2013 Contents ACKNOWLEDGEMENTS ...............................................................................................
    [Show full text]
  • Meeting the Salinity Requirements of the Bivalve Mollusc Crassostrea
    water Article Meeting the Salinity Requirements of the Bivalve Mollusc Crassostrea gigas in the Depuration Process and Posterior Shelf-Life Period to Improve Food Safety and Product Quality João A. Silvestre 1,Sílvia F. S. Pires 2 , Vitória Pereira 2 , Miguel Colaço 1, Ana P. L. Costa 2 , Amadeu M. V. M. Soares 2 , Domitília Matias 3, Filipa Bettencourt 3, Sergio Fernández-Boo 4, Rui J. M. Rocha 2,* and Andreia C. M. Rodrigues 2 1 Department of Biology, University of Aveiro, 3810-193 Aveiro, Portugal; [email protected] (J.A.S.); [email protected] (M.C.) 2 CESAM (Centre for Marine and Environmental Studies), Department of Biology, University of Aveiro, 3810-193 Aveiro, Portugal; [email protected] (S.F.S.P.); [email protected] (V.P.); [email protected] (A.P.L.C.); [email protected] (A.M.V.M.S.); [email protected] (A.C.M.R.) 3 IPMA, Instituto Português do Mar e da Atmosfera, 8700-305 Olhão, Portugal; [email protected] (D.M.); [email protected] (F.B.) 4 Centro Interdisciplinar de Investigação Marinha e Ambiental (CIIMAR), Universidade do Porto, Avenida General Norton de Matos, S/N, 4450-208 Matosinhos, Portugal; [email protected] * Correspondence: [email protected] Citation: Silvestre, J.A.; Pires, S.F.S.; Abstract: Microbiological contamination of bivalve molluscs is one of the major concerns inherent to Pereira, V.; Colaço, M.; Costa, A.P.L.; food safety, thus depuration is frequently needed to assure food safety levels associated with their Soares, A.M.V.M.; Matias, D.; consumption. Salinity plays an important role in the metabolic activity of bivalves and as such can Bettencourt, F.; Fernández-Boo, S.; influence their depuration capacity.
    [Show full text]
  • Aspects of the Biology of Juvenile Barramundi Lates Calcarifer (Bloch
    ResearchOnline@JCU This file is part of the following reference: Barlow, Christopher G. (1998) Aspects of the biology of juvenile barramundi Lates calcarifer (Bloch) relevant to production for recreational fisheries and farming, with a note on the proposal to introduce Nile perch Lates niloticus (L.) to Australia. PhD thesis, James Cook University. Access to this file is available from: http://eprints.jcu.edu.au/24097/ The author has certified to JCU that they have made a reasonable effort to gain permission and acknowledge the owner of any third party copyright material included in this document. If you believe that this is not the case, please contact [email protected] and quote http://eprints.jcu.edu.au/24097/ Aspects of the biology of juvenile barramundi Lates calcarifer (Bloch) relevant to production for recreational fisheries and farming, with a note on the proposal to introduce Nile perch Lates niloticus (L.) to Australia Thesis submitted by Christopher G. BARLOW BSc (JCUNQ) MSc (UNSW) in January 1998 for the degree of Doctor of Philosophy in the Department of Zoology at qvR cv4.7-vee- James Cook University of North Queensland STATEMENT ON ACCESS I, the undersigned, the author of this thesis, understand that James Cook University of North Queensland will make it available for use within the University Library and, by microfilm or other means, allow access to users in other approved libraries. All users consulting this thesis will have to sign the following statement: `In consulting this thesis I agree not to copy or closely paraphrase it in whole or in part without the written consent of the author; and to make proper written acknowledgement for any assistance which I have obtained from it.' Beyond this, I do not wish to place any restriction on access to this thesis.
    [Show full text]
  • TLR3 038 73038 NT Humpty Doo Barramundi Farm FACT
    FOOD WITH MIGUEL MEASTRE TOP END BBQ’D BARRAMUNDI Miguel heads to Humpty Doo Barramundi farm just outside Darwin to check out Australia's favourite fish. The farm raises 'barra' from the runt stage right through to the dinner plate! And that's exactly what Miguel is after, but he's was catch it first. That means into the pen with a cricket helmet and his bare hands. With his catch of the day, Miguel cooks up a delicious barramundi dish with a spectacular NT sunset to finish. FAST FACTS • Darwin is the capital of the Northern Territory and the most northern city in Australia and is located on the coasts of the Timor Sea. • Darwin is situated at the top of the state and known as the ‘Top End’. • The population of Darwin is estimated to be around 127,532 and represents half of the Northern Territory population. • There are more crocodiles in the Northern Territory than anywhere else in the world. • Darwin has two distinct seasons; the ‘Wet’ is from November until April and the ‘Dry’ season from May to October, with plenty of activities on offer during both seasons. • At 1,352,172 sQ km Northern Territory is the third largest state in Australia behind Western Australia and Queensland. • Darwin has been rebuilt twice; first after being bombed by World War Two and secondly from Cyclone Tracey in 1974. Hence the modern-looking city. Source: http://www.abs.gov.au/websitedbs/corporate.nsf/home/ABS+Offices+-+Northern+Territory http://www.travelnt.com/travelling-in-the-nt/weather-and-seasons.aspx HUMPTY DOO BARRAMUNDI Humpty Doo Barramundi produce year round supplies of premium Saltwater Barramundi.
    [Show full text]
  • The Status of the Black Bream Acanthopagrus Butcheri (Pisces: Sparidae) Population in Lake Clifton, South-Western Australia
    Journal of the Royal Society of Western Australia, 94: 25–28, 2011 The status of the black bream Acanthopagrus butcheri (Pisces: Sparidae) population in Lake Clifton, south-western Australia K A Smith & J Norriss Department of Fisheries, P.O. Box 21, North Beach, 6020, Australia. Corresponding author: [email protected] Manuscript received August 2010; accepted December 2010 Abstract Lake Clifton hosts the largest living, non-marine thrombolite (microbialite) reef in the southern hemisphere. The thrombolite reef was recently listed as a critically endangered ecological community. The main threat to the ecology of the lake is increasing salinity, but other threats have also been identified, including the impact of the introduced fish Acanthopagrus butcheri (Munro, 1949). Samples opportunistically collected after a fish kill in 2007 indicated that A. butcheri in this lake experienced very low somatic growth and recruitment failure between 1995 and 2007, probably in response to hypersalinity. The evidence suggests that the A. butcheri population in Lake Clifton is effectively extinct. The proposed conservation strategy for Lake Clifton addresses a range of identified threats, including the eradication of A. butcheri. However, management action in response to this particular threat may no longer be required. The abundance of A. butcheri in the lake is probably very low and the population is likely to become extinct if current environmental trends continue. A dramatic reduction in growth rate after 1995 demonstrates the extraordinary growth plasticity of A. butcheri in response to environmental influences. Keywords: salinity, fish kill, growth, Sparidae, thrombolite Introduction 1987). Hence, a shift from permanently hyposaline to permanently hypersaline conditions threatens the Lake Clifton is a small, permanently closed, coastal survival of the key microbial species responsible for lake on the south-west coast of Western Australia, thrombolite formation.
    [Show full text]
  • Factors Required for the Successful Aquaculture of Black Bream In
    Determination of the biological parameters required for managing the fisheries of four tuskfish species and western yellowfin bream Fairclough, D. V., Hesp S. A., Potter, I. C. & N. G. Hall Project No. 2000/137 Fisheries Research and Development Corporation Report FRDC project 2000/137 Determination of the biological parameters required for managing the fisheries of four tuskfish species and western yellowfin bream Fairclough D.V. Hesp S.A. Potter I.C. Hall N.G. June 2004 Centre for Fish and Fisheries Research Murdoch University Murdoch, Western Australia 6150 This work is copyright. Except as permitted under the Copyright Act 1968 (Cth), no part of this publication may be reproduced by any process, electronic or otherwise, without the specific written permission of the copyright owners. Neither may information be stored electronically in any form whatsoever without such permission. June 2004 ISBN: 0-646-39851-2 2 Table of Contents NON-TECHNICAL SUMMARY:............................................................................................6 OUTCOMES ACHIEVED TO DATE .......................................................................................6 ACKNOWLEDGEMENTS.......................................................................................................9 1.0 GENERAL INTRODUCTION .......................................................................................10 1.1 BACKGROUND ...................................................................................................10 1.2 NEED.....................................................................................................................13
    [Show full text]