Tasmanian Aquaculture Research Articles

Belly Up: How Corporate Interests Are Keeping an Unsustainable Tasmanian Aquaculture Afloat and Failing to Protect the Welfare of the Nonhuman Animals Affected

AbstractThe Tasmanian salmon industry has become one of the state's most profitable industries to date. Though production conditions notoriously lack transparency, there is a clear dependency on the mass production of complex nonhuman animals who are kept in inappropriate conditions and subject to harmful industry practices. This article explores why the Tasmanian Environmental Protection Agency recently approved the construction of the largest salmon hatchery in Australia, despite serious environmental sustainability and welfare concerns. It considers the likely impact of the new hatchery on the welfare of both the farmed nonhuman animals and the surrounding free-ranging life and advocates for industry improvements that are guided by considerations of nonhuman animal welfare and environmental sustainability.

Belly Up: How Corporate Interests Are Keeping an Unsustainable Tasmanian Aquaculture Afloat and Failing to Protect the Welfare of the Nonhuman Animals Affected

Belly Up: How Corporate Interests Are Keeping an Unsustainable Tasmanian Aquaculture Afloat and Failing to Protect the Welfare of the Nonhuman Animals Affected

Big Fish, Small Pond: NGO–Corporate Partnerships and Corruption of the Environmental Certification Process in Tasmanian Aquaculture

Aquaculture is the single largest agribusiness in the Australian state of Tasmania, with local company, Tassal, the foremost producer of farm-raised salmon in the country. Tassal has come under considerable criticism for its environmental impact, despite the fact that since 2014, the Aquaculture Stewardship Council (ASC) and the World Wildlife Fund have certified it consistently as a sustainable business. This article argues that these endorsements are the result of a corrupt corporate arrangement that is designed purposefully to mislead consumers. It examines the considerable payments to both non-governmental organizations from Tassal and the questionable nature of the certification process administered by the ASC.

Multiple step ahead river flow modelling for south east tasmanian aquaculture

We develop multiple step ahead prediction models of river flow for locations in Tasmania (Australia) for decision support in aquaculture. In predicting river flows for multiple days ahead, we first statistically determine the maximum input lags of rainfall and river flow. We then use machine learning techniques in building models. In multiple step ahead prediction, we consider both static and dynamic approaches. In dynamic approach, one day prediction is served as input to two days ahead prediction. The experimental results demonstrate that, in general, a dynamic approach provides better accuracy in multiple day’s ahead prediction. For Duck Bay location using dynamic approach, support vector regression performs best over linear regression, M5P and multilayer perceptron. However, at Montagu Bay location, we find that M5P performs best over methods. We find that multiple step ahead prediction of river flow for each location requires modelling of lags with associated machine learning techniques.

Experimentally induced marine flexibacteriosis in Atlantic salmon smolts Salmo salar. II. Pathology

The fish disease marine flexibacteriosis is characterised by necrotic lesions on the body, head, fins, and occasionally gills, with erosive lesions on the external surface as the prominent clinical sign. In Australia, the main species affected are Atlantic salmon Salmo salar and rainbow trout Oncorhynchus mykiss in sea-cage culture in Tasmania. Using a dose-dependent trial to determine pathology, 2 forms of the disease were noted in Atlantic salmon. The acute form occurs within 2 to 3 d after inoculation at high doses (1 x 10(8) cells ml(-1)) and is characterised by the disintegration of the epithelium. The chronic form of the disease began as small superficial blisters of the epidermis, which develop into ulcerative lesions that leave musculature exposed. The predominant lesion sites were the dorsum and pectoral fins. Jaws were commonly affected, and gill necrosis was also noted. Behaviour of Atlantic salmon as well as the conditions under which they were kept contribute to the size and distribution of lesions observed. Lack of an inflammatory response in pathology and rapid and destructive mortalities observed in higher inoculum doses suggested a role of toxins in the pathogenesis of Tenacibaculum maritimum. This is the first study to examine the development of marine flexibacteriosis lesions and to utilise immunohistochemistry to verify that the bacteria observed in histology was T. maritimum.

Relationships between mobile macroinvertebrates and reef structure in a temperate marine reserve

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 389:31-44 (2009) - DOI: https://doi.org/10.3354/meps08210 Relationships between mobile macroinvertebrates and reef structure in a temperate marine reserve Timothy J. Alexander*, Neville Barrett, Malcolm Haddon, Graham Edgar Marine Research Laboratories, Tasmanian Aquaculture and Fisheries Institute, University of Tasmania, Private Bay 49, Tasmania 7001, Australia *Email: tja0@utas.edu.au ABSTRACT: Relationships between different metrics of reef structure and the density of macroinvertebrates were examined at 3 nested spatial scales inside and outside a long-established, ‘no-take’ marine protected area (MPA) at Maria Island, Tasmania, Australia. Generalized linear models were developed that best explained the contributions of rugosity, substratum composition (different-sized boulders, bedrock, sand) and refuge metrics to the spatial variability in invertebrate species richness, total abundance, and the abundances of major taxonomic classes and focal species. To distinguish responses associated with protection from fishing from those relating to natural geographic variation, relationships between reef structure and invertebrate density were also assessed using survey data from before the MPA came into effect. Models combining reef structure and MPA protection explained between 44 to 67% of spatial variability of total invertebrate abundance across all survey scales examined (1 × 5, 1 × 50 and 1 × 200 m). The number of refuge size categories provided the best predictor of invertebrate species richness at the 5 m scale; however, no reef structure metric investigated was significant at the largest (200 m) spatial scale for species richness. Amongst the explanatory variables examined, MPA protection and density of small refuges generated significant responses for the majority of taxa. One commonly applied metric of reef structure, rugosity, was found to be a relatively poor predictor of invertebrate abundance and richness, generating few significant relationships. Comparisons with pre-MPA data indicated that protection from fishing greatly influenced most major components of the invertebrate community, while reef structure appears to have little interactive influence on these MPA effects at the scales tested here. KEY WORDS: Rugosity · Spatial refuges · Marine protected area · Sea urchins · Crinoids · Generalized linear model · Species richness · Tasmania Full text in pdf format PreviousNextCite this article as: Alexander TJ, Barrett N, Haddon M, Edgar G (2009) Relationships between mobile macroinvertebrates and reef structure in a temperate marine reserve. Mar Ecol Prog Ser 389:31-44. https://doi.org/10.3354/meps08210 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 389. Online publication date: September 04, 2009 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2009 Inter-Research.

Effects of skeletal deformities on swimming performance and recovery from exhaustive exercise in triploid Atlantic salmon

The occurrence of spinal deformity in aquaculture can be considerable, and a high rate of deformity has been suggested in triploid smolts in Tasmania. However, the physiological performance of fish with skeletal deformities has not been addressed. The swimming performance and oxygen consumption of triploid Atlantic salmon smolts with either a vertebral fusion (platyspondyly) or multifocal scoliosis were compared to normal (non-deformed) triploid smolts. Fish with vertebral fusion attained swim speeds similar to normal fish, whereas scoliotic fish were unable to attain comparable swim speeds. Routine and maximum oxygen consumption was higher for deformed fish compared with normal fish, translating into apparent increased routine metabolic scope in vertebral fusion fish, and equivocal scope in scoliotic fish compared with normal controls. Deformed fish developed a lower excess post-exercise oxygen consumption compared to non-deformed fish, suggesting they are either incapable of sustained anaerobic activity or possess an increased recovery capacity. These data suggest that skeletal deformity has differential effects on swimming performance depending upon the type of deformity but imposes a significant metabolic cost on salmon smolts.

A new species of copepod (Siphonostomatoida: Caligidae) parasitic on the striped trumpeter, Latris lineata (Forster), from Tasmania

A new species of caligid copepod (Siphonostomatoida), Caligus nuenonnae n. sp., is described based on material collected from the body surface of striped trumpeter [Latris lineata (Forster)] reared at the Tasmanian Aquaculture and Fisheries Institute, Marine Research Laboratories, Australia. Caligus nuenonnae n. sp. is characterised by the following combination of features: 1) female genital complex with a mid-lateral indentation and highly concave posterior margin; 2) 1-segmented abdomen in the female that is about one-third the length of the genital complex; 3) distinctly broader first abdominal somite relative to the second abdominal somite in the male; 4) antenna with a spatulate process on the proximal segment; 5) recurved postantennal process without a basal accessory process; 6) female maxilliped with a proximal ridged protrusion on the corpus; 7) sternal furca with widely separated, apically truncate tines; 8) distal exopodal segment of leg 1 with a lateral flange on each apical spine and an accessory process on apical spines two and three; 9) leg 3 protopod with two adhesion pads on the dorsolateral surface; 10) leg 4 exopod 2-segmented, with I-0; I, III armature; 11) terminal exopodal segment of leg 4 with the outer apical spine being slightly shorter than the middle apical spine; 12) male maxillulary dentiform process with numerous small points embossed on the surface; and 13) male legs 5 and 6 represented by distinct lobate projections.

Determining the age and growth of wild octopus using stylet increment analysis

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 367:213-222 (2008) - DOI: https://doi.org/10.3354/meps07558 Determining the age and growth of wild octopus using stylet increment analysis Stephen C. Leporati*, Jayson M. Semmens, Gretta T. Pecl Tasmanian Aquaculture and Fisheries Institute Marine Research Laboratories, University of Tasmanian, Private Bag 49, Hobart, Tasmania 7001, Australia *Email: stephen.leporati@utas.edu.au ABSTRACT: Stylet increment analysis is a method of octopus age estimation that quantifies growth rings within stylets (reduced internal shells found in the mantle). This method was applied to wild Octopus pallidus to determine gender and seasonal influences on age and growth. A total of 503 individuals (94 males and 409 females) were aged, revealing that O. pallidus can reach a maximum age of approximately 1.6 yr and that spawning occurs throughout the year. Male octopuses on average were significantly larger (550 and 482 g for males and females, respectively) and older (259 and 243 d for males and females, respectively) than female, and overall growth rates were positively correlated with temperature at hatching. However, these differences were secondary to individual growth heterogeneity. Growth of males ranged from 1.32 to 5.33% body weight (bw) d–1 and females from 1.55 to 6.9% bw d–1, with no relationship between age and size evident regardless of sex. Stylet increment analysis is a promising technique that could play a role similar role to statoliths in squid as an ageing tool. KEY WORDS: Octopus · Stylet increment analysis · Age · Growth · Seasonal effects Full text in pdf format PreviousNextCite this article as: Leporati SC, Semmens JM, Pecl GT (2008) Determining the age and growth of wild octopus using stylet increment analysis. Mar Ecol Prog Ser 367:213-222. https://doi.org/10.3354/meps07558 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 367. Online publication date: September 11, 2008 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2008 Inter-Research.

Mitigating fur seal interactions: relocation from Tasmanian aquaculture farms

Abstract At Tasmanian salmon aquaculture farms, fur seals were trapped and relocated to reduce interactions with stock, operations and equipment. From 1990 to 2005, 4517 relocations of 1124 seals were undertaken, peaking at 1203 relocations in 2003. Of the relocations, 56% were recaptured seals. Most seals had less than 10 captures (46%), with 3% trapped more than 20 times. Relocations were mostly seasonal, occurring in the austral winter and spring with a peak in August. Seal recapture intervals were highly variable, ranging from days to years. Within the same year, recapture intervals per seal ranged from 4 to 258 days, mean 36 days. Australian fur seals were trapped more frequently than New Zealand fur seals. The first trapped New Zealand fur seal was identified in 2000. Relocation provides short‐term relief from seal interactions but does not mitigate the interaction problem in the longer term. The core of the seal interaction problem is the current inability to exclude seals from pens and fish stock. Salmon farms are providing a predictable, accessible food source for seals. Copyright © 2008 John Wiley & Sons, Ltd.

THE FIRST CHONDRACANTHID (COPEPODA: CYCLOPOIDA) REPORTED FROM CULTURED FINFISH, WITH A REVISED KEY TO THE SPECIES OF CHONDRACANTHUS

A new species of the Chondracanthidae (Copepoda: Cyclopoida), Chondracanthus goldsmidi, is described based on material collected from the nasobranchial region of striped trumpeter (Latris lineata [Forster]) cultured at the Tasmanian Aqua-culture and Fisheries Institute, Marine Research Laboratories, Australia. This represents the first report of a chondracanthid copepod infecting cultured finfish and the first metazoan parasite from cultured striped trumpeter. Chondracanthus goldsmidi n. sp. can be distinguished from its female congeners by the absence of lateral processes on the head and the presence of 3 pairs of lateral trunk outgrowths, 3 middorsal body outgrowths (of which the first 2 are rounded), a small and subcylindrical antennule, and unornamented legs 1 and 2. A revised key to the 39 valid species of Chondracanthus is provided.

Pentacapsula neurophila sp.n. (Multivalvulida) from the central nervous system of striped trumpeter, Latris lineata (Forster)

Striped trumpeter, Latris lineata, are being experimentally cultured by the Tasmanian Aquaculture and Fisheries Institute at Taroona, Tasmania. Fish surviving over 30 days post-hatching have frequently developed nervous aberrations associated with a severe granulomatous meningoencephalomyelitis. The myxozoan parasite Pentacapsula neurophila sp.n. was revealed as the parasite causing the disease in the striped trumpeter juveniles. Measurements made of isolated spores indicated that the organism was distinct from all previously described Pentacapsula species. This is the first report of a marine myxozoan parasite of the genus Pentacapsula in Australian waters.

Effect of processing soybean meal on the apparent digestibility of practical diets for the greenback flounder Rhombosolea tapirina (Günther)

Aquaculture ResearchVolume 30, Issue 9 p. 719-723 Effect of processing soybean meal on the apparent digestibility of practical diets for the greenback flounder Rhombosolea tapirina (Günther) M. P. Bransden, M. P. Bransden School of Aquaculture and Tasmanian Aquaculture and Fisheries Institute, University of Tasmania, Launceston, Tasmania, AustraliaSearch for more papers by this authorC. G. Carter, C. G. Carter School of Aquaculture and Tasmanian Aquaculture and Fisheries Institute, University of Tasmania, Launceston, Tasmania, AustraliaSearch for more papers by this author M. P. Bransden, M. P. Bransden School of Aquaculture and Tasmanian Aquaculture and Fisheries Institute, University of Tasmania, Launceston, Tasmania, AustraliaSearch for more papers by this authorC. G. Carter, C. G. Carter School of Aquaculture and Tasmanian Aquaculture and Fisheries Institute, University of Tasmania, Launceston, Tasmania, AustraliaSearch for more papers by this author First published: 09 October 2008 https://doi.org/10.1046/j.1365-2109.1999.00367.xCitations: 11 Dr C G Carter, School of Aquaculture, University of Tasmania, PO Box 1214, Launceston, Tasmania 7250, Australia AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Citing Literature Volume30, Issue9September 1999Pages 719-723 RelatedInformation

The pathology of Flexibacter maritimus in aquaculture species in Tasmania, Australia

Macroscopic and microscopic features of natural and experimental Flexibacter maritimus infection, and epidemiological aspects of the disease, have been reported in a number of species of fish in Tasmanian aquaculture including Atlantic salmon, Salmo salar L., rainbow trout, Oncorhynchus mykiss (Walbaum), greenback flounder, Rhombosolea tapirina Günther, and striped trumpeter, Latris lineata (Bloch & Schneider). There is a great deal of consistency in the pathology in salmonids and non‐salmonid species, with erosive lesions of external surfaces being the most prominent clinical sign. Experimentally induced disease of salmonids and flounder is similar to natural infection. Mature lesions show dermal and gill erosion, with dermal bacterial invasion into the dense connective tissue and occasionally underlying musculature, but a remarkable lack of inflammatory response. The earliest lesions show consistent fragmentation and degeneration of the epithelium, with infiltration of amorphous protein‐like materials and occasionally intra‐epithelial cellular inflammatory cells, plus congestion and haemorrhage of the superficial dermis, but without visible bacteria in standard sections. Variable scale loss, oedema and a low level of inflammation in scale pockets, plus variable small adherent bacterial mats, are evident before full epithelial erosion.