Journal articles: 'Nemadactyllus macropterus'

1

Gauldie, R. W. "The Morphological Basis of Fish Age Estimation Methods Based on the Otolith of Nemadactylus macropterus." Canadian Journal of Fisheries and Aquatic Sciences 51, no. 10 (October 1, 1994): 2341–62. http://dx.doi.org/10.1139/f94-237.

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Relationships between the anatomy of the endolymphatic sac, sac otoconia, sagitta and astericus of Nemadactylus macropterus (Cheilodactylidae: Teleostei) are described and the variation in opaque and hyaline zones, sulcal checks, and daily microincrement widths along different growth axes of the otolith measured. The quantitative morphology of the otolith is used to compare the different age estimation techniques for N. macropterus that are based on opaque and hyaline zones, sulcal checks, and daily microincrements. Comparison of the different methods shows that at the present state of knowledge daily microincrements present the most credible age estimation method for N. macropterus.

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2

Coulson, P. G., S. A. Hesp, I. C. Potter, and N. G. Hall. "Life cycle characteristics of the Blue Morwong Nemadactylus valenciennesi, compared with those of other species of Cheilodactylidae." Marine and Freshwater Research 61, no. 1 (2010): 104. http://dx.doi.org/10.1071/mf08341.

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The demonstration by this study that the life cycle characteristics of the reef fish Nemadactylus valenciennesi differed markedly from those of other cheilodactylids led us to compare these differences and hypothesise on their evolutionary implications. The distribution, length and age compositions, growth and the length and age at maturity of N. valenciennesi in south-western Australian waters have been determined. The maximum age (21 years) of N. valenciennesi (maximum total length = 984 mm) is far less than those of the much smaller Cheilodactylus fuscus, Nemadactylus macropterus (both ~40 years) and Cheilodactylus spectabilis (97 years). Yet N. valenciennesi, N. macropterus and C. spectabilis mature at a similar young age (3–7 years). While, on the basis of data for other species, all three species mature at lengths consistent with their asymptotic lengths, the last two species mature at a far earlier age than would be predicted from their long life spans. The early attainment of maturity by N. macropterus and C. spectabilis may reflect a response to high juvenile mortality or constrained adult growth, whereas their long life spans could reflect a response to variable recruitment in the past or compensation for limited annual reproductive output due to very constrained adult growth.

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3

Sabadel, AJM, LM Durante, and SR Wing. "Stable isotopes of amino acids from reef fishes uncover Suess and nitrogen enrichment effects on local ecosystems." Marine Ecology Progress Series 647 (August 13, 2020): 149–60. http://dx.doi.org/10.3354/meps13414.

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In 1979, the Suess effect was described as decreasing δ13C in the oceans linked to anthropogenic CO2 emissions. After years of over-fertilization of farming soils and runoff, we hypothesized that δ15N in coastal environments would also decline, whereby synthetic fertilizers lead to depletion of the heavy isotope 15N. We used museum-preserved and modern samples of 3 fishes from Otago, New Zealand, to reconstruct the isotopic baselines of C and N and assess specific trophic positions through time (1955-present) based on bulk and amino acid stable isotope values. Our sample set included Odax pullus, a strictly herbivorous species, and 2 commercially important species: Nemadactylus macropterus and Parapercis colias. Muscle tissue of the fishes recorded the change in δ13CBulk through time, which matched estimated Suess effect values for New Zealand. We also resolved the effects on the C isotopic baseline from natural changes in the food web using analysis of the δ13C of essential amino acids and found that while P. colias maintained a steady diet, the food web position of N. macropterus likely changed. Analysis of δ15N of phenylalanine in O. pullus indicated a decrease of 0.023‰ yr-1 since 1955, which corroborates our coastal N-enrichment hypothesis. Furthermore, we found that isotopic changes for N. macropterus were consistent with overfishing and habitat degradation in the region. These data provide vital information for our resolution and understanding of how past environments have changed in terms of both anthropogenic influences on coastal food web structure and biogeochemical cycles of C and N in marine ecosystems.

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4

Grewe, Peter M., Adam J. Smolenski, and Robert D. Ward. "Mitochondrial DNA Diversity in Jackass Morwong (Nemadactylus macropterus: Teleostei) from Australian and New Zealand Waters." Canadian Journal of Fisheries and Aquatic Sciences 51, no. 5 (May 1, 1994): 1101–9. http://dx.doi.org/10.1139/f94-109.

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The jackass morwong (Nemadactylus macropterus), a commercially valuable marine fish in the Australian–New Zealand region, was surveyed for genetic variation as part of a larger project aimed at clarifying its stock structure. Mitochondrial DNA variation in 166 jackass morwong from seven southern Australian localities was examined using nine restriction enzymes. The 28 haplotypes identified gave an overall nucleon diversity of 0.671. Mean nucleotide diversity per sample was 0.458%, with a (corrected) nucleotide divergence among samples of 0.001%. There was no significant spatial patterning. Five hundred individuals from eight southern Australian localities and one New Zealand locality were examined using three restriction enzymes detecting polymorphic cut sites. The 33 haplotypes identified gave an overall nucleon diversity of 0.635. Mean nucleotide diversity per sample was 1.247%, with a (corrected) nucleotide divergence among samples of 0.002%. No differentiation was detected among the Australian localities. The New Zealand sample showed weak but significant divergence from the Australian samples. These results were similar to those from a concurrent allozyme analysis, and we conclude that there is appreciable nuclear and mitochondrial DNA gene flow among Australian localities, while the Tasman Sea separating Australia from New Zealand acts as a partial barrier.

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5

Wankowski, Jacek W. J., Edward Hyduke, and Stephen Williams. "Population age structure and mortality rates of jackass morwong (Nemadactylus macropterus) in Eastern Bass Strait, Australia." Fisheries Research 6, no. 4 (September 1988): 317–35. http://dx.doi.org/10.1016/0165-7836(88)90002-1.

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6

Jordan, Alan R. "Age, growth and spatial and interannual trends in age composition of jackass morwong, Nemadactylus macropterus, in Tasmania." Marine and Freshwater Research 52, no. 4 (2001): 641. http://dx.doi.org/10.1071/mf99157.

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Transverse sections of sagittae were examined. The first and second annual increments were defined by examination of the progression of otolith radius and length of the 0+ and 1+ cohorts. Growth in both sexes is rapid until ~5 years old (32–35 cm), and then slows appreciably. There was a broad range of lengths within individual age-classes, with a maximum of 12 age-classes present in a 1 cm length-class. Maximum ages of males and females were 41 and 30 years, respectively, which is considerably higher than previously estimated from whole otoliths. There was no significant difference in the growth curves between males and females, although this is influenced by the large number of juveniles and by the examination of relatively few large, older fish. The sex-specific von Bertalanffy growth parameters are: L∞ 38.4 cm FL, t0 –0.07 years, K 0.36 year–1 for females and L∞ 36.2 cm FL, t0 0.15 years, K 0.42 year–1 for males. The age composition was dominated by 4–7 year olds but showed evidence of considerable recruitment variability, particularly in the strong 1988 year-class. The relationship between the life-history strategy of N. macropterus and recruitment variability is discussed.

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7

Elliott, NG, and RD Ward. "Enzyme variation in jackass morwong, Nemadactylus macropterus (Schneider, 1801) (Teleostei: Cheilodactylidae), from Australian and New Zealand waters." Marine and Freshwater Research 45, no. 1 (1994): 51. http://dx.doi.org/10.1071/mf9940051.

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Nemadactylus macropterus was sampled from eight localities around southern Australia, ranging from Western Australia to New South Wales, and from one area off the western coast of New Zealand. Thirty-three enzyme loci were analysed by gel electrophoresis. Average heterozygosity per locus per sample was 10.1 %, ranging from 8.4% to 11.I% per sample. Although no significant differentiation was observed among the Australian samples, there was significant differentiation between the Australian and New Zealand samples. This was primarily attributable to variation at the sAAT-I * locus, where the common allele had a frequency of around 0.80 in Australian samples and around 0.94 in the New Zealand sample (P<0.001). Across all 33 loci, 0.47% of the total genetic variation in Australian and New Zealand samples was due to differentiation between these two areas. This is significantly greater (P=0.001) than the value of 0.17% that could be ascribed to sampling error alone. Two loci (ADH* and GPI-I *) that had previously been reported as monomorphic in New Zealand specimens were found to be polymorphic in the New Zealand samples analysed in this study, and allele frequencies at these loci were indistinguishable from Australian samples.

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8

Bruce, B. "Influence of mesoscale oceanographic processes on larval distribution and stock structure in jackass morwong (Nemadactylus macropterus: Cheilodactylidae)." ICES Journal of Marine Science 58, no. 5 (October 2001): 1072–80. http://dx.doi.org/10.1006/jmsc.2001.1099.

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9

Castillo-Jordán, Claudio, Neil L. Klaer, Geoffrey N. Tuck, Stewart D. Frusher, Luis A. Cubillos, Sean R. Tracey, and Michael J. Salinger. "Coincident recruitment patterns of Southern Hemisphere fishes." Canadian Journal of Fisheries and Aquatic Sciences 73, no. 2 (February 2016): 270–78. http://dx.doi.org/10.1139/cjfas-2015-0069.

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Three dominant recruitment patterns were identified across 30 stocks from Australia, New Zealand, Chile, South Africa, and the Falkland Islands using data from 1980 to 2010. Cluster and dynamic factor analysis provided similar groupings. Stocks exhibited a detectable degree of synchrony among species, in particular the hakes and lings from Australia, New Zealand, Chile, and South Africa. We tested three climate indices, the Interdecadal Pacific Oscillation (IPO), Southern Annular Mode (SAM), and Southern Oscillation Index (SOI), to explore their relationship with fish stock recruitment patterns. The time series of IPO and SOI showed the strongest correlation with New Zealand hoki (blue grenadier, Macruronus novaezelandiae) and Australian jackass morwong (Nemadactylus macropterus) (r = 0.50 and r = –0.50), and SAM was positively related to Australian Macquarie Island Patagonian toothfish (Dissostichus eleginoides) (r = 0.49). Potential linkages in recruitment patterns at sub-basin, basin, and multibasin scales and regional and global climate indices do account for some of the variation, playing an important role for several key Southern Hemisphere species.

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10

Klaer, Neil L. "Abundance indices for main commercial fish species caught by trawl from the south-eastern Australian continental shelf from 1918 to 1957." Marine and Freshwater Research 55, no. 6 (2004): 561. http://dx.doi.org/10.1071/mf03182.

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Per-haul records of catches by steam trawlers on the south-eastern Australian continental shelf from 1918 to 1957 were examined for the main commercial species tiger flathead (Neoplatycephalus richardsoni), jackass morwong (Nemadactylus macropterus), redfish (Centroberyx affinis), latchet (Pterygotrigla polyommata) and chinaman leatherjacket (Nelusetta ayraudi). Catch rates in weight per haul per species were standardised to annual indices of abundance using a log-linear model. Standardised annual index trends for flathead, latchet and leatherjacket indicate a strong to severe decline during the period covered by the data. All species showed seasonal patterns, but the peak season varied depending on the species. The distribution of standardised catch rate by area also differed greatly by species, and no single area showed consistent differences across all species. Day trawls caught more flathead, redfish and latchet, while night trawls caught more morwong and leatherjacket. Moon phase had less influence on catch rates than other factors. The correlation of annual index trends to a number of annual mean environmental factors was examined and no strong correlations were found.

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11

STATHAM, JO A., H. ALLAN BREMNER, and ANTHONY R. QUARMBY. "Storage of Morwong (Nemadactylus macropterus Bloch and Schneider) in Combinations of Polyphosphate, Potassium Sorbate and Carbon Dioxide at 4oC." Journal of Food Science 50, no. 6 (November 1985): 1580–84. http://dx.doi.org/10.1111/j.1365-2621.1985.tb10538.x.

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12

Piasente, M., I. A. Knuckey, S. Eayrs, and P. E. McShane. "In situ examination of the behaviour of fish in response to demersal trawl nets in an Australian trawl fishery." Marine and Freshwater Research 55, no. 8 (2004): 825. http://dx.doi.org/10.1071/mf04054.

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In situ examination of the behaviour of fish was undertaken with underwater cameras positioned on demersal trawl gear used by Australia’s South East Trawl Fishery. Blue grenadier (Macruronus novaezelandiae), pink ling (Genypterus blacodes) and whiptails (Coelorinchus spp.) swam in an anguilliform mode whereas other species displayed a carangiform swimming mode. Tiger flathead (Neoplatycephalus richardsoni) and ocean perch (Heliocolenus spp.) were active in response to the approaching trawl net compared with the generally passive activity of whiptails, New Zealand dory (Cyttus novaezelandiae), and jackass morwong (Nemadactylus macropterus). However, when in the body of the trawl, gemfish were active while ocean perch, whiptails and New Zealand dory were generally passive. Some blue grenadier, ocean perch and whiptails escaped capture by passing through open meshes in the trawl mouth, whereas tiger flathead passed under the ground gear. In the trawl body, small numbers of blue grenadier passed through open meshes in the top panel whereas numerous spotted warehou swam faster than the towing speed, presumably escaping capture by swimming forwards and out of the trawl. Interspecific behavioural variation in escape response could be utilised to design more efficient trawl gears.

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13

Jordan, Alan R. "Spatial and temporal variations in abundance and distribution of juvenile and adult jackass morwong, Nemadactylus macropterus, in south-eastern Tasmania." Marine and Freshwater Research 52, no. 4 (2001): 661. http://dx.doi.org/10.1071/mf99156.

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Depth-stratified random demersal trawl surveys of the shelf of southern and eastern Tasmania from summer 1993 to summer 1995 showed seasonal variations in abundance of N. macropterus in all depth strata, although the trend varied between years, with abundance peaking in summer 1993 and winter 1994. This variation is attributed to the seasonal movement of fish from south-eastern Tasmanian shelf waters, although some seasonal change in size composition is also evident. Catch rates were highest on the outer shelf and lowest on the inner shelf, reflecting the distinct size-structuring, with juveniles concentrated on the inner and mid shelf and mature fish on the outer shelf. Size compositions differed among shelf regions, with few mature fish on the mid shelf of Storm Bay compared with the same stratum on the east coast, indicating that the bay is primarily a nursery area for the species. Settlement from the pelagic post-larval phase occurred in spring and early summer at 7–9 cm, with evidence of movement between inner-and mid-shelf strata by autumn. Abundance of 0+ fish was highest in 1993 and 1994 and a considerable decrease in the abundance in both regions in 1995. The influences of local hydrography and the large size at settlement are discussed.

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14

Wayte, Sally E. "Management implications of including a climate-induced recruitment shift in the stock assessment for jackass morwong (Nemadactylus macropterus) in south-eastern Australia." Fisheries Research 142 (May 2013): 47–55. http://dx.doi.org/10.1016/j.fishres.2012.07.009.

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15

Klaer, N. L. "Steam trawl catches from south-eastern Australia from 1918 to 1957: trends in catch rates and species composition." Marine and Freshwater Research 52, no. 4 (2001): 399. http://dx.doi.org/10.1071/mf00101.

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Haul-by-haul steam trawler catch and effort data for 1918–23, 1937–43 and 1952–57, which cover a large portion of the history of steam trawling in the Australian South East Fishery, were examined in detail for the first time. There were 64371 haul records in total. The catch-rate for all retained catch combined shows a strong decline overall, with a brief recovery during World War II, probably due to increased retention of previously discarded species. The fishing fleet moved to more distant fishing grounds and deeper waters as the catch-rate declined. The catch-rates of the main commercial species followed a similar pattern in a number of regions within the fishery. The catch-rate of the primary target species – tiger flathead (Neoplatycephalus richardsoni) – dropped considerably from the early, very high, catch-rates. Chinaman leatherjacket (Nelusetta ayraudi) and latchet (Pterygotrigla polyommata) – species that were apparently abundant in the early years of the fishery, virtually disappeared from catches in later years. The appearance of greater catches of jackass morwong (Nemadactylus macropterus), redfish (Centroberyx affinis) and shark/skate during the war and afterwards was probably due to increased retention of catches of these species. The disappearance of certain species from the catch may be due to high fishing pressure alone, or to a combination of fishing pressure, changes in the shelf habitat possibly caused by the trawl gear, and environmental fluctuations.

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16

Audzijonyte, Asta, Elizabeth A. Fulton, and Anna Kuparinen. "The impacts of fish body size changes on stock recovery: a case study using an Australian marine ecosystem model." ICES Journal of Marine Science 72, no. 3 (November 3, 2014): 782–92. http://dx.doi.org/10.1093/icesjms/fsu185.

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Abstract Many fished stocks show long-term reductions in adult body size. Such changes could lead to new feeding interactions and alter stock productivity, introducing new levels of uncertainty in fisheries management. We use a marine ecosystem model parameterized for Southeast Australia to explore how reductions (up to 6% in 50 years) in size-at-age of fished species affect stock recovery after an implementation of a fishing moratorium. We show that reduction in body size can greatly elevate predation mortality and lower the post-fishing biomass of affected species. In our simulations, the recovery period after the fishing moratorium was characterized by two phases. In the initial readjustment phase, the ecosystem dynamics was largely determined by the rapid changes in the biomasses of recovering species and changes in body size had negligible effects. In contrast, fish body sizes had the major impact on the biomasses in the second, semi-equilibrium state and the final biomasses were generally not affected by the harvest rate during the fishing period. When reduced size-at-age elevated predation mortality in most age groups of a species (tiger flathead Platycephalus richardsoni or silver warehou Seriolella punctata in our simulations), the species' equilibrium biomass was considerably lower compared with the scenarios of no change in body size. For other species (pink ling Genypterus blacodes and jackass morwong Nemadactylus macropterus), a predation increase in some age groups was balanced by the decrease in others. The latter reduction in predation mortality occurred when major predators of species with reducing size-at-age were decreasing in size themselves, or when cannibalism was an important source of juvenile mortality (in blue grenadier Macruronus novaezelandiae). We suggest that decreased size-at-age will be most detrimental to stock recovery when the main predators of the stock are not affected by the drivers causing changes in body size.

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17

Papa, Yvan, Alexander G. Halliwell, Mark A. Morrison, Maren Wellenreuther, and Peter A. Ritchie. "Phylogeographic structure and historical demography of tarakihi (Nemadactylus macropterus) and king tarakihi (Nemadactylus n.sp.) in New Zealand." New Zealand Journal of Marine and Freshwater Research, April 7, 2021, 1–25. http://dx.doi.org/10.1080/00288330.2021.1912119.

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Journal articles on the topic 'Nemadactyllus macropterus'

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