Using Conditional Lorenz Curves to Examine Consolidation in New Zealand Commercial Fishing

2012 ◽  
Vol 27 (4) ◽  
pp. 303-321 ◽  
Author(s):  
Kobi Abayomi ◽  
Tracy Yandle
Keyword(s):  
New Zealand ◽  
Commercial Fishing ◽  
Lorenz Curves

scholarly journals Kahawai Phylogeny and Phylogenetics:  A Genetic Investigation into Commercial and Recreational Fisheries Management and Practice

2021 ◽  
Author(s):  
◽  
Brenton Hodgson
Keyword(s):  
New Zealand ◽  
Common Ancestor ◽  
Coastal Communities ◽  
Commercial Fishing ◽  
Recreational Fisheries ◽  
Monophyletic Clade ◽  
Genetic Investigation ◽  
Fish Stocks ◽  
Modern Times ◽  
The Family

<p>Globally, commercially exploited fish species are coming under more and more pressure as the population of humans grow. Protein from the sea has traditionally been available to coastal communities throughout history. In modern times however, traditional artisanal fisheries have been replaced by commercial fishing industries. It is estimated by some authorities that these modern fisheries have led to decreases in pre-exploitation biomass of desirable species of up to 90%. As desirable species decline, secondary species become more valuable and subject to exploitation. An issue with this exploitation is that management decisions of fish stocks are often based on political or commercial concerns rather than sound science focussed on preserving stocks, and ultimately, fishing industries. To investigate phylogenetic and phylogeographic relationships of fish, kahawai (Arripis trutta) was used as a proxy species. A. trutta is one of only four members of the genus Arripis, which in turn is the sole member of the family Arripidae. It was found that a single, highly connected population of A. trutta inhabit New Zealand waters, and approximately 15 migrants per generation make the journey between New Zealand and Australia, genetically linking these populations. A phylogeny of A. trutta was resolved using mitochondrial DNA, and while COX1 data supported the hypothesis that A. trutta forms a monophyletic clade within the Stromateoids (medusa fish, squaretails and drift fish) and the Scombrids (tuna, mackerel and their allies) suggesting a common ancestor, other data collected during the investigation does not support this hypothesis.</p>

The Potential for Historical Studies of Fisheries in Australia and New Zealand

2001 ◽  
pp. 181-206 ◽  
Author(s):  
Malcolm Tull ◽  
Tom Polacheck
Keyword(s):  
New Zealand ◽  
Primary Sources ◽  
Commercial Fishing ◽  
Secondary Literature ◽  
Trawl Fishery ◽  
Small Family ◽  
The Impact

Malcolm Tull, Tom Polacheck, and Neil Klaer examine the primary sources - particularly printed statistical sources - and secondary literature in order to understand the impact of commercial fishing and harvesting of fish across Australia and New Zealand - including a case study of the multi-species Southeast Australain Trawl Fishery. The authors note that fisheries in Australia and New Zealand have historically been managed by small, family operations, so the records pertining to them are sparse. As a result, most of the records in this chapter come from governmental sources - such as reports and inquiries into Australasian fisheries.

Another New Zealand centenarian: age validation of black cardinalfish (Epigonus telescopus) using lead–radium and bomb radiocarbon dating

2017 ◽  
Vol 68 (2) ◽  
pp. 352 ◽  
Author(s):  
Dianne M. Tracey ◽  
Allen H. Andrews ◽  
Peter L. Horn ◽  
Helen L. Neil
Keyword(s):  
New Zealand ◽  
Growth Zone ◽  
Commercial Fishing ◽  
Age Validation ◽  
Fishing Activity ◽  
Combined Application ◽  
Bomb Radiocarbon ◽  
Otolith Core ◽  
Radiometric Ages ◽  
Lead 210

Black cardinalfish (Epigonus telescopus, Apogonidae) is an important component of deepsea commercial fishing activity in the New Zealand region. It is estimated to live longer than 100 years on the basis of counts of unvalidated annual growth zones in otoliths. Age-validation procedures for long-lived fishes are often one of the following two techniques: (1) lead–radium disequilibria, which uses the natural decay of radium-226 into lead-210 as a natural clock; or (2) bomb radiocarbon (Δ14C) dating, which relies on the marine signal created by nuclear testing. The high estimated lifespan, as well as the large size of the otolith core region, make E. telescopus an excellent candidate for a combined application of these two independent age-validation techniques. The lead–radium dating using otolith cores indicated that growth-zone counts less than ~60 years were consistent with radiometric ages, whereas higher counts appeared to be under-estimates. There was 95% confidence that maximum age was at least 95 years. The validation indicated that fish aged over 60 years tended to be under-aged by up to 30%. The bomb radiocarbon levels in otolith cores supported age estimates up to ~40 years made from zone counts, and by inference from the zone counts validated with lead–radium dating, longevity exceeds 100 years.

scholarly journals Investigating spatiotemporal variation in the diet of Westland Petrel through metabarcoding, a non-invasive technique

2020 ◽  
Author(s):  
Marina Querejeta ◽  
Marie-Caroline Lefort ◽  
Vincent Bretagnolle ◽  
Stéphane Boyer
Keyword(s):  
New Zealand ◽  
Foraging Behaviour ◽  
Invasive Technique ◽  
Morphological Identification ◽  
Commercial Fishing ◽  
Close Link ◽  
Non Invasive ◽  
Ecological Requirements ◽  
Geographical Variations ◽  
Different Seasons

AbstractAs top predators, seabirds are directly impacted by any changes in marine communities, whether they are linked to climate change or caused by commercial fishing activities. However, their high mobility allows them to adapt to changing conditions. For example, seabirds can adapt their foraging behaviour according to the resources available at different seasons. This capacity of adaptation comes to light through the study of their diet. Traditionally, the diet of seabirds is assessed through the morphological identification of prey remains in regurgitates, a method that is invasive for the bird and limited in terms of resolution. However, the recent optimization of DNA-based approaches is now providing a non-invasive and more comprehensive and accurate characterization of animals’ diet. Here, we used a non-invasive metabarcoding approach to characterize the diet of the Westland petrel (Procellaria westlandica), an endangered burrowing species, endemic to the South Island of New Zealand. We collected 99 fresh faecal samples at two different seasons and in two different sub-colonies. Besides from describing the diet of the Westland petrel, our aim was to account for seasonal and geographical variations in the diet of the petrel and assess potential links with the fishery industry in New Zealand.We found that amphipods were the most common prey, or secondary prey, followed by cephalopods and fish, suggesting a close link between the composition of prey items and New Zealand’s commercial fishing activities but, also, some level of natural predation. Our results show significant differences in diet between seasons (before hatching vs chick rearing season) and between sampling sites (two sub-colonies 1.5 km apart), which suggests variability and adaptability in the foraging strategy of the Westland petrel.Due to its non-invasive nature, the method used here can be applied on a great number of samples to draw a comprehensive picture of the diet dynamic in seabirds and unravel their adaptability or ecological requirements. This work demonstrates how environmental DNA can inform the conservation of an endangered species with elusive foraging behaviour, providing, in this case, valuable information regarding the diet preferences of an iconic species within New Zealand’s biodiversity.

scholarly journals Occupational Health and Safety in the New Zealand Fishing Industry: Preliminary Finding of the Key Issues

1970 ◽  
Author(s):  
Jeremy Hayman ◽  
Danae Anderson ◽  
Felicity Lamm
Keyword(s):  
New Zealand ◽  
Social Issues ◽  
Labour Force ◽  
Health And Safety ◽  
Preliminary Finding ◽  
Commercial Fishing ◽  
Fishing Industry ◽  
Diverse Workforce ◽  
Fishing Vessels ◽  
Fishing Sector

In 2008 there were approximately 3,500 registered commercial fishing vessels in New Zealand and 2,500 full­time employees working in the industry, a fraction of New Zealand’s two million plus labour force. However, in the Maritime New Zealand’s Annual Report 2000­2001 it was reported that New Zealand’s commercial fishing sector represented a disproportionately high number of maritime fatalities. With the exception of the 2007 fatality figures, the rate of Maritime New Zealand reported fatalities and accidents within the commercial fishing sector have remained fairly static. As a result, there have been a variety of initiatives implemented in this hazardous industry, for example, FishSAFE, and a number of reviews undertaken. However, unlike other sectors, implementing OHS interventions in the fishing industry has to account for a number of unique features such as the employment strata, geographical isolation of job, precariousness of employment, increasingly a diverse workforce and social issues such as substance abuse, and. This paper reports on preliminary findings based on interview data of employers and employees in the New Zealand fishing industry. In particular, it exposes a number of barriers to implementing and maintaining OHS measures, for example, increasingly tight profit margins, time pressures, and confusion around regulatory requirements. The initial findings also indicate that the command and control structure of managing staff in the fishing industry can influence individual and group perception and acceptance of risk. Finally, the paper highlights areas requiring further investigation.

Eels at the Edge: Science, Status, and Conservation Concerns

2009 ◽  
Keyword(s):  
New Zealand ◽  
Substantial Reduction ◽  
Theoretical Models ◽  
Commercial Fishing ◽  
Silver Eel ◽  
Glass Eel ◽  
Frequency Distributions ◽  
Anguilla Australis ◽  
The Status ◽  
Commercial Glass

<em>Abstract.—</em>The two main species of freshwater eels in New Zealand, the shortfin <em>Anguilla australis </em>and the endemic longfinned eel <em>A. dieffenbachii</em>, are extensively commercially exploited and also support important customary fisheries. Since there are no commercial glass eel fisheries in New Zealand, other indices must be used to indicate changes in recruitment over time. While there is some anecdotal evidence of reductions in glass eel recruitment, there is evidence of poorly represented cohorts of longfins within some populations, and modeling of these data indicate a substantial reduction in recruitment over the past two decades. Growth of both species is typically slow at 2–3 cm per year, meaning that both species are susceptible to commercial capture for many years until spawning escapement. Extensive commercial fishing has resulted in more substantial changes in length-frequency distributions of longfins than in shortfins; likewise, regional reductions in catch per unit effort are more significant for longfins. Theoretical models of silver eel escapement indicate that longfin females are especially susceptible to overexploitation. Shortfins would have been more impacted than longfins by loss of wetlands, but the impact of hydro stations on upstream access for juvenile eels and downstream access for silver eels would have been more severe for longfins. Overall, there is no clear evidence that the status of shortfin eel stocks has been seriously compromised by the extensive commercial eel fishery, but there is increasing evidence that longfins are unable to sustain present levels of exploitation.

scholarly journals Using fish-processing time to carry out acoustic surveys from commercial vessels

2005 ◽  
Vol 62 (2) ◽  
pp. 295-305 ◽  
Author(s):  
Richard L. O'Driscoll ◽  
Gavin J. Macaulay
Keyword(s):  
New Zealand ◽  
Processing Time ◽  
Cost Effective ◽  
Small Scale ◽  
Commercial Fishing ◽  
Fish Processing ◽  
Acoustic Surveys ◽  
Catch Rates ◽  
Time Required ◽  
High Catch

Abstract In some fisheries large factory freezer trawlers have periods of down time as the catch is processed. By utilizing this time, scientific acoustic surveys can be carried out between commercial-fishing operations without compromising fishing success. Examples are presented from three acoustic surveys for hoki (Macruronus novaezelandiae) in New Zealand waters during 2002 and 2003 conducted from a commercial vessel fitted with a scientifically calibrated SIMRAD ES-60 echosounder. These surveys confirmed the presence of a new spawning area for hoki and provided biomass estimates from known fishing grounds. The approach described works well for small-scale acoustic surveys adjacent to areas of high catch rates and is cost-effective because the vessel “pays for itself” by fishing commercially. The major limitation is that the boundaries of the survey area are determined by the time available during processing, which is related to the size of the catch and the time required to search for a suitable location for the next commercial trawl. In the New Zealand hoki surveys, processing time was typically 3–8 h, which was sufficient to carry out about 10–70 km of acoustic transects. Acoustic research was also limited to periods of relatively good conditions by the use of a hull-mounted transducer.

scholarly journals Demographics of Etmopterus lucifer (Lucifer dogfish)

2021 ◽  
Author(s):  
◽  
Annie Rose Galland
Keyword(s):  
New Zealand ◽  
Growth Model ◽  
Growth Models ◽  
Total Mortality ◽  
Information Criterion ◽  
Commercial Fishing ◽  
Precautionary Approach ◽  
Late Maturity ◽  
Trawl Fisheries ◽  
Age Estimates

<p>This study provides the first comprehensive description of the demographics of lucifer dogfish (Etmopterus lucifer) from the Chatham Rise, New Zealand during January 2012. Lucifer dogfish is a non-QMS species commonly taken as bycatch in New Zealand deepwater trawl fisheries, where it has low commercial value and is usually discarded. Sexual maturity of females was determined by assessing the condition of the ovary and uterus, and the width of the uterus and oviducal gland. Male maturity was assessed by determining clasper and testes condition, inner clasper length, testes length, and testes weight. A sample of lucifer dogfish was aged by counting growth bands on the internal section of the dorsal fin spine (n = 97), assuming annual deposition of bands. Intra- and inter-reader bias in age estimates was estimated, but count precision was high within (CV = 12.71 %) and between reader age estimates (11.98 %). A number of growth models were fitted to the length-at-age data, including the traditional and modified Von Bertalanffy growth formula (VBGF) and four cases of the Schnute growth model. Selection of the best growth model was based on the Akaike Information Criterion (AIC). The fourth case of the Schnute growth model best represented growth. Lucifer dogfish had an estimated age and length at maturity of 10.4 years and 34.0 cm respectively for males, and 13.0 years and 41.0 cm for females. The oldest observed fish were 17 and 14 years for males and females respectively. The total mortality estimates were in the range of 0.14 to 0.35 yr ⁻¹. Lucifer dogfish fed primarily upon mesopelagic fishes, with Hector’s lanternfish (Lampanyctodes hectoris) identified as being the most common prey. Lucifer dogfish had late maturity relative to its longevity. Although sampling of the population was likely to be incomplete, and biases in age estimates may have occurred, these observed life history characteristics indicate that productivity will be low, and as a consequence, the precautionary approach should be applied, as the potential impact of commercial fishing on this species is high.</p>

scholarly journals Seabird and Marine Mammal Bycatch Reduction Through Fishing Industry Funded Research: The New Zealand Conservation Services Levy Program

1999 ◽  
Vol 33 (2) ◽  
pp. 13-18 ◽  
Author(s):  
West Ian F. ◽  
Janic Molloy ◽  
Michael F. Donoghue ◽  
Chris Pugsley
Keyword(s):  
New Zealand ◽  
Marine Mammals ◽  
Wildlife Conservation ◽  
Commercial Fishing ◽  
Fishing Industry ◽  
Protected Species ◽  
The Status ◽  
Extensive Consultation ◽  
By Catch ◽  
Marine Wildlife

Since 1995 the New Zealand government has implemented a scheme to recover from the domestic commercial fishing industry the funding required to investigate and mitigate the impacts of fishing on protected species of marine wildlife. Conservation Services Levies are approved by the Minister of Conservation, administered by the Department of Conservation (DOC), and are collected by the Ministry of Fisheries. The levies are set annually following extensive consultation between the relevant government agencies and stakeholder groups. Levies are primarily used to boost observer coverage in selected fisheries, to monitor the status of protected species known to be incidentally taken in fishing operations, and to develop ways of mitigating the by-catch of species protected under the New Zealand Marine Mammals Protection Act 1978 and the Wildlife Act 1953. Conservation Services Levies provide a rare example in the global fishing industry of a transparent and accountable process, requiring the industry to pay at least part of the true environmental costs of its operation. It would be premature to suggest that the introduction of these levies has achieved a resolution of the various interactions between commercial fisheries and protected species of marine wildlife.

Sign in / Sign up

Export Citation Format

Share Document