Recreational Harvest of Sharks and Rays in Western Australia Is Only a Minor Component of the Total Harvest

Sharks and rays are a global conservation concern with an increasing number of species considered at risk of extinction, mostly due to overfishing. Although the recreational harvest of sharks and rays is poorly documented and generally minimal, it can be comparable to the commercial harvest. In this study, we quantified the recreational harvest of sharks and rays in Western Australia, a region with a marine coastline greater than 20,000 km. A total of 33 species/taxonomic groups were identified, with the harvest dominated by dusky and bronze whalers, blacktip reef sharks, gummy sharks, Port Jackson sharks, wobbegongs, and rays and skates. Eighty-five percent of individuals were released with an unknown status (alive or dead). We found a latitudinal gradient of species composition, with tropical and subtropical species of the genus Carcharhinus dominating in the north and temperate species from a range of families dominating in the south. Overall, our findings showed that the recreational harvest was negligible when compared with commercial landings.

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Recreational Harvest of Sharks and Rays in Western Australia is only a Minor Component of the Total Harvest

10.21203/rs.3.rs-225321/v1 ◽

2021 ◽

Author(s):

Matias Braccini ◽

Eva Lai ◽

Karina Ryan ◽

Stephen Taylor

Keyword(s):

Western Australia ◽

Time Series Data ◽

Minor Component ◽

Series Data ◽

Commercial Fishing ◽

The North ◽

Commercial Harvest ◽

Conservation Concern ◽

Taxonomic Groups ◽

A Minor

Abstract Sharks and rays are of global conservation concern with an increasing number of species at risk of extinction, mostly attributed to overfishing by commercial fishing. Their recreational harvest is poorly known but it can be of similar magnitude to the commercial harvest in some regions. We quantified the recreational harvest of sharks and rays in Western Australia, a region with a marine coastline of > 20,000 km. We recorded 33 species/taxonomic groups but the harvest was dominated by dusky and bronze whalers, blacktip reef shark, gummy shark, Port Jackson shark, wobbegongs, and rays and skates. Most species caught were released (85% of all individuals), although gummy and whiskery sharks were typically retained. There was a clear latitudinal gradient of species composition with tropical and subtropical species of the genus Carcharhinus dominating in the north and temperate species of the families Triakidae, Carcharhinidae, Heterodontidae and Rajidae dominating in the south. The recreational harvest was negligible compared with commercial landings. The newly available time series data can be incorporated into stock assessments to allow the quantification of recreational fishing mortality of shark and ray species and therefore comply with state, national and international initiatives for their conservation and sustainable management.

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Predicting the hatching date of Malleefowl Leipoa ocellata eggs without excavating the mound

10.20938/afo38078086 ◽

2021 ◽

Vol 38 ◽

pp. 78-86

Keyword(s):

Western Australia ◽

Egg Production ◽

Hatching Success ◽

Cost Effective ◽

Breeding Population ◽

Egg Laying ◽

The North ◽

Remote Cameras ◽

Invasive Method ◽

Conservation Concern

The Malleefowl Leipoa ocellata (Family Megapodiidae) has suffered a major contraction in its distribution across Australia and is considered vulnerable to extinction. It incubates its eggs in a mound. A key conservation concern for this species is the level of recruitment of young into the breeding population. One approach for measuring recruitment success is to mark chicks as they emerge from the mound. Traditional methods have involved excavating the mound in order to determine the rate of egg production, hatching success and to predict the timing of hatching. This is laborious, involves significant disturbance and may pose a risk to the eggs or chicks. A less invasive method, using remote cameras to determine the date of egg-laying and hatching, and length of incubation, was tested to help predict when chicks emerge from their mound. In the mound studied at Matuwa in central Western Australia, 19 eggs were laid from 26 August 2017 to 27 January 2018, with eggs being laid earlier in the day as temperature increased and as time progressed. An average incubation period of 61.25 days was observed for four chicks that were recorded emerging from the mound. This study has provided evidence that remote cameras can be used to help determine the number of eggs laid and their hatching success and to predict emergence times of Malleefowl chicks without needing to excavate mounds. Further development of this technique as a more cost-effective and passive alternative for providing information on chick recruitment is recommended to help facilitate the recovery of the species. It was also of interest to record details of the mound observed here as the study site was located on the north-eastern limit ofthe known Malleefowl range in Western Australia, where there are few detailed records.

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The Age and Origin of the Jinfosi Biotite Granite, North Qilian, NW China: Evidence from U–Pb Zircon Age Data, Geochemistry, and Nd–Sr–Pb Isotopes

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.616-618.3 ◽

2012 ◽

Vol 616-618 ◽

pp. 3-18 ◽

Cited By ~ 1

Author(s):

Xing Li Sun ◽

Xiao Huang Liu ◽

Jiu Feng Liu ◽

Bai Nian Sun

Keyword(s):

Minor Component ◽

Biotite Granite ◽

Pb Isotopes ◽

Zircon Age ◽

Nw China ◽

The North ◽

Material Values ◽

A Minor ◽

Shrimp Zircon ◽

North Qilian

New geochemistry, Nd–Sr–Pb isotopes and U–Pb zircon data from the Jinfosi Biotite granite provide important constraints on the evolution of the crust in this part of the North Qilian, NW China. The Jinfosi Biotite granite have the following properties: SiO2 > 65%, A/CNK(Molar Al2O3/(CaO + Na2O + K2O) ratios generally > 1.1, Na2O generally < 3.2%, Sm/Nd values between 0.17 and 0.27, and high Rb/Sr values. A chondrite-normalized rare earth element (REE) pattern shows negative Eu anomalies and depletion in heavy REEs. 143Nd/144Nd values are relatively low, and values of εNd(t) and εSr(t) are indicative of continental lithosphere. (87Sr/86Sr)i values are between 0.69952 and 0.70962, corresponding to continental crust mixed with a minor component of mantle material. Values of 206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb are 18.9–19.0, 15.59–15.85, and 38.00–and 39.00, respectively, corresponding to S-type collision-related granites. The Jinfosi Biotite granite yield a SHRIMP zircon U–Pb age of 416.7 ± 4.1 Ma. R1–R2 and Rb versus (Yb + Nb) discrimination diagrams indicate that the Jinfosi biotite granite was produced during continental collision following closure of the paleo-North Qilian Ocean.

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Overview of the status of Atlantic salmon (Salmo salar) in the North Atlantic and trends in marine mortality

ICES Journal of Marine Science ◽

10.1093/icesjms/fss013 ◽

2012 ◽

Vol 69 (9) ◽

pp. 1538-1548 ◽

Cited By ~ 114

Author(s):

Gérald Chaput

Keyword(s):

Atlantic Salmon ◽

Salmo Salar ◽

North Atlantic ◽

North Atlantic Ocean ◽

Minor Component ◽

Atlantic Salmon Salmo Salar ◽

The North ◽

The Status ◽

The North Atlantic ◽

A Minor

Abstract Chaput, G. 2012. Overview of the status of Atlantic salmon (Salmo salar) in the North Atlantic and trends in marine mortality. – ICES Journal of Marine Science, 69: 1538–1548. Since the early 1980s, the ICES Working Group on North Atlantic Salmon has collated and interpreted catch data, exchanged information on research initiatives, and provided advice to managers in support of conservation efforts for Atlantic salmon. During the past three decades, the annual production of anadromous Atlantic salmon from more than 2000 rivers draining into the North Atlantic has been less than 10 million adult-sized salmon. This represents a minor component, by number and biomass, of the pelagic ecosystem in the North Atlantic Ocean. Ideally, Atlantic salmon would be assessed and managed based on river-specific stock units, the scale that best corresponds to the spawner to recruitment dynamic. In reality, comparatively few river-specific assessments are available for either the Northwest or the Northeast Atlantic. The marine survival of Atlantic salmon is low and, based on return rates of smolts to adults from monitored rivers, has declined since the mid- to late 1980s. Abundance has declined more severely for the multi-sea-winter components, and especially in the southern areas of the species' range. Common patterns in abundance, inferred at the level of stock complex in the North Atlantic, suggest that broad-scale factors are affecting productivity and abundance and that they are acting throughout the salmon's time at sea.

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Fisheries of the Forth, Scotland

Proceedings of the Royal Society of Edinburgh Section B Biological Sciences ◽

10.1017/s0269727000006898 ◽

1987 ◽

Vol 93 (3-4) ◽

pp. 479-494

Author(s):

F. G. Howard ◽

D. W. McKay ◽

A. W. Newton

Keyword(s):

Minor Component ◽

Population Characteristics ◽

The North ◽

The North Sea ◽

Firth Of Forth ◽

Over Exploitation ◽

A Minor ◽

Demersal Species ◽

Made In ◽

Pelagic Fisheries

SynopsisHistorical aspects of the Firth of Forth fisheries are described, and the present state of the stocks of exploited species is reviewed. The once-substantial pelagic fisheries have declined and now constitute only a minor component of the firth fisheries. Herring fisheries were based on spring spawning herring but the herring now caught in the firth are from stocks of overwintering juveniles of autumn spawning herring. Recent conservation measures have closed many of the firth grounds to herring and sprat fishing. The main demersal species caught are cod, haddock, whiting, plaice and lemon sole. Most landings are from catches made in the middle and outer firths and the North Sea. The demersal pair trawl is now the most important gear used in directed demersal fishing. The most important shellfish fishery is that for the Norway lobster, current landings being valued at £2·4 million. Over-exploitation resulted in a decline in the stocks in the late 1970s. They are now recovering. Recent studies suggest that population characteristics of Norway lobsters are influenced by the physical environment. The firth today is one of the most intensively exploited areas in Scotland for lobster and crabs. Other exploited shellfish include squid, winkles and mussels.

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Demersal cephalopods of the Gulf of Carpentaria, Australia

Marine and Freshwater Research ◽

10.1071/mf9940351 ◽

1994 ◽

Vol 45 (3) ◽

pp. 351 ◽

Cited By ~ 6

Author(s):

M Dunning ◽

S McKinnon ◽

CC Lu ◽

J Yeatman ◽

D Cameron

Keyword(s):

Minor Component ◽

Abundant Species ◽

Northern Australia ◽

Australian Species ◽

The North ◽

Sepia Pharaonis ◽

Catch Rates ◽

A Minor ◽

North Western ◽

High Catch

Demersal trawl and dredge surveys of the Gulf of Carpentaria in the early summers of 1990 and 1991 provided the first comprehensive assessment of the cephalopod fauna of this shallow, tropical basin off northern Australia. Twenty-one taxa (comprising five loliginid squids, seven cuttlefishes, seven octopuses and two dumpling squids) were recorded. In addition to hosting species distributed broadly in the Indo-West Pacific (e.g. loliginid squids Sepioteuthis lessoniana, Photololigo cf. chinensis and P. cf. edulis; cuttlefishes Sepia eiliptica and Sepia pharaonis), the Gulf of Carpentaria represents the most northwesterly extent of the range of some eastern Australian species (e.g. Loliolus noctiluca and Sepia whitieyana). Squid catches were lower in the north-western gulf in 1990 and higher in shallower water during the more geographically restricted survey in 1991, whereas cuttlefish were more evenly distributed throughout the different sampling areas in both years. Broad size ranges of both sexes of the four most abundant species (P. cf. chinensis (northern form), P. cf. eduiis, S. eiliptica and S. pharaonis) are indicative of extended spawning seasons, and fully mature individuals of these species were evident throughout the gulf. Cephalopods are a minor component in reported domestic fisheries catches from the Gulf of Carpentaria, where penaeid prawns are targeted. High (though seasonal) squid catch rates were reported annually by Taiwanese trawlers targeting butterfish and squid from certain areas prior to 1979. With the observed population structure of the abundant cephalopod species and relatively high catch rates in some localities during these recent surveys, it is suggested that the cephalopod resources of the Gulf of Carpentaria could support increased commercial fisheries exploitation.

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Protonation effects on dynamic flux properties of aqueous metal complexes

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc2009091 ◽

2009 ◽

Vol 74 (10) ◽

pp. 1543-1557 ◽

Cited By ~ 8

Author(s):

Herman P. Van Leeuwen ◽

Raewyn M. Town

Keyword(s):

Complex Formation ◽

Metal Ion ◽

Good Description ◽

Minor Component ◽

Outer Sphere ◽

Metal Species ◽

Central Metal ◽

Inner Sphere ◽

A Minor ◽

Protonated Ligand

The degree of (de)protonation of aqueous metal species has significant consequences for the kinetics of complex formation/dissociation. All protonated forms of both the ligand and the hydrated central metal ion contribute to the rate of complex formation to an extent weighted by the pertaining outer-sphere stabilities. Likewise, the lifetime of the uncomplexed metal is determined by all the various protonated ligand species. Therefore, the interfacial reaction layer thickness, μ, and the ensuing kinetic flux, Jkin, are more involved than in the conventional case. All inner-sphere complexes contribute to the overall rate of dissociation, as weighted by their respective rate constants for dissociation, kd. The presence of inner-sphere deprotonated H2O, or of outer-sphere protonated ligand, generally has a great impact on kd of the inner-sphere complex. Consequently, the overall flux can be dominated by a species that is a minor component of the bulk speciation. The concepts are shown to provide a good description of experimental stripping chronopotentiometric data for several protonated metal–ligand systems.

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Statherian (ca. 1714–1680 Ma) Extension-Related Magmatism and Deformation in the Southwestern Korean Peninsula and Its Geological Significance: Constraints from the Petrological, Structural, Geochemical and Geochronological Studies of Newly Identified Granitoids

Minerals ◽

10.3390/min11060557 ◽

2021 ◽

Vol 11 (6) ◽

pp. 557

Author(s):

Byung-Choon Lee ◽

Weon-Seo Kee ◽

Uk-Hwan Byun ◽

Sung-Won Kim

Keyword(s):

Korean Peninsula ◽

Tectonic Setting ◽

Alkali Feldspar ◽

Ductile Deformation ◽

Southwestern Part ◽

The North ◽

Deformation Event ◽

Geochemical Analyses ◽

A Minor ◽

T Values

In this study, petrological, structural, geochemical, and geochronological analyses of the Statherian alkali feldspar granite and porphyritic alkali feldspar granite in the southwestern part of the Korean Peninsula were conducted to examine petrogenesis of the granitoids and their tectonic setting. Zircon U-Pb dating revealed that the two granites formed around 1.71 Ga and 1.70–1.68 Ga, respectively. The results of the geochemical analyses showed that both of the granites have a high content of K2O, Nb, Ta, and Y, as well as high FeOt/MgO and Ga/Al ratios. Both granites have alkali-calcic characteristics with a ferroan composition, indicating an A-type affinity. Zircon Lu-Hf isotopic compositions yielded negative εHf(t) values (−3.5 to −10.6), indicating a derivation from ancient crustal materials. Both granite types underwent ductile deformation and exhibited a dextral sense of shear with a minor extension component. Based on field relationships and zircon U-Pb dating, it was considered that the deformation event postdated the emplacement of the alkali feldspar granite and terminated soon after the emplacement of the porphyritic alkali feldspar granite in an extensional setting. These data indicated that there were extension-related magmatic activities accompanying ductile deformation in the southwestern part of the Korean Peninsula during 1.71–1.68 Ga. The Statherian extension-related events are well correlated with those in the midwestern part of the Korean and eastern parts of the North China Craton.

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Diet among oil-workers on off-shore oil installations in the Norwegian sector of the North Sea

British Journal Of Nutrition ◽

10.1079/bjn19920062 ◽

1992 ◽

Vol 68 (1) ◽

pp. 11-19 ◽

Cited By ~ 2

Author(s):

A. Oshaug ◽

L. I. Østgård ◽

K. U. Trygg

Keyword(s):

North Sea ◽

Heart Diseases ◽

Daily Intake ◽

Minor Role ◽

Coronary Heart Diseases ◽

Average Daily Intake ◽

The North ◽

The North Sea ◽

Oil Workers ◽

A Minor

Dietary studies based on 24 h recalls were carried out on four oil installations in the Norwegian sector of the North Sea. Two hundred and three persons were interviewed about what they had eaten the previous 24 h. Food purchased for the installations in the previous 5 months was recorded. Results based on 24 h recalls showed that average daily intake of energy was 12.2 MJ of which 17% came from protein, 44% from fat and 39% from carbohydrate, including 8% from sugar. Meat, vegetables, fresh fruits, seafood (shellfish), french fries, eggs, cream and ice-cream were important components of the diet, while bread, fish and cereals played a minor role. Average daily intake (mg) of nutrients were: calcium 1244, iron 15, vitamin A 1049 μg, vitamin D 4.1 μg, thiamin 1.6, riboflavin 2.2, nicotinic acid 22, ascorbic acid 143. Dietary fibre intake, estimated as unavailable carbohydrate, was on average 19 g, and the average daily intake of cholesterol was 755 mg. Intakes were compared with the Norwegian recommended dietary allowance. Most of the employees chose a diet which when eaten over a longer period of time may contribute to the development of coronary heart diseases (CHD) and thereby increase the morbidity and mortality from CHD in the oil industry.

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Toward a global reference database of COI barcodes for marine zooplankton

Marine Biology ◽

10.1007/s00227-021-03887-y ◽

2021 ◽

Vol 168 (6) ◽

Author(s):

Ann Bucklin ◽

Katja T. C. A. Peijnenburg ◽

Ksenia N. Kosobokova ◽

Todd D. O’Brien ◽

Leocadio Blanco-Bercial ◽

...

Keyword(s):

Species Diversity ◽

Dna Sequences ◽

Reference Sequence ◽

Global Ocean ◽

Reference Database ◽

Data Repositories ◽

Marine Zooplankton ◽

The North ◽

Coi Sequences ◽

Taxonomic Groups

AbstractCharacterization of species diversity of zooplankton is key to understanding, assessing, and predicting the function and future of pelagic ecosystems throughout the global ocean. The marine zooplankton assemblage, including only metazoans, is highly diverse and taxonomically complex, with an estimated ~28,000 species of 41 major taxonomic groups. This review provides a comprehensive summary of DNA sequences for the barcode region of mitochondrial cytochrome oxidase I (COI) for identified specimens. The foundation of this summary is the MetaZooGene Barcode Atlas and Database (MZGdb), a new open-access data and metadata portal that is linked to NCBI GenBank and BOLD data repositories. The MZGdb provides enhanced quality control and tools for assembling COI reference sequence databases that are specific to selected taxonomic groups and/or ocean regions, with associated metadata (e.g., collection georeferencing, verification of species identification, molecular protocols), and tools for statistical analysis, mapping, and visualization. To date, over 150,000 COI sequences for ~ 5600 described species of marine metazoan plankton (including holo- and meroplankton) are available via the MZGdb portal. This review uses the MZGdb as a resource for summaries of COI barcode data and metadata for important taxonomic groups of marine zooplankton and selected regions, including the North Atlantic, Arctic, North Pacific, and Southern Oceans. The MZGdb is designed to provide a foundation for analysis of species diversity of marine zooplankton based on DNA barcoding and metabarcoding for assessment of marine ecosystems and rapid detection of the impacts of climate change.

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