An update of the pulse logbook data collected in 2017-2020

Abstract We present the outcomes of a collaborative research programme tasked with reducing bycatch, and thus discards in a temperate Australian prawn trawl fishery. Sea trials in the Gulf of St Vincent, South Australia, assessed the performance of a modified trawlnet that incorporated a rigid polyethylene grid and a T90-mesh codend. Compared with conventional designs, the modified net yielded marked reductions in bycatch (cumulatively >81% by weight), with pronounced decreases in sponge (92%), elasmobranchs (80%), teleost fish (71%), molluscs (61%), and crustaceans (78%). Using commercial logbook data, we estimate that the use of modified nets could reduce discards by ∼240 tons per year. This outcome was achieved with moderate declines in the catch rate (kg h−1) of the target species, Western King Prawn (mean ∼15%), of which almost all were small adults of low commercial value. Adoption of the modified net by industry was realized in March 2012, because it met environmental objectives (i.e. reducing bycatch and improving public perceptions of sustainability), reduced prawn damage, demonstrated commensurate financial returns, and engaged stakeholders throughout the development process. Overall, the project provides a useful example of bycatch research with demonstrable outcomes of improving the ecological and economic sustainability of prawn harvests.

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Standardizing catch rates: is logbook information by itself enough?

ICES Journal of Marine Science ◽

10.1093/icesjms/fsm179 ◽

2008 ◽

Vol 65 (2) ◽

pp. 255-266 ◽

Cited By ~ 25

Author(s):

J. Bishop ◽

W. N. Venables ◽

C. M. Dichmont ◽

D. J. Sterling

Keyword(s):

Relative Abundance ◽

Prediction Models ◽

Expert Knowledge ◽

External Information ◽

Linear Regression Models ◽

Catch Per Unit Effort ◽

Estimation Model ◽

Catch Rates ◽

Logbook Data ◽

Estimation Models

Abstract Bishop, J., Venables, W. N., Dichmont, C. M., and Sterling, D. J. 2008. Standardizing catch rates: is logbook information by itself enough? – ICES Journal of Marine Science, 65: 255–266. The goal of the work was to maximize the accuracy of standardized catch per unit effort as an index of relative abundance. Linear regression models were fitted to daily logbook data from a multispecies penaeid trawl fishery in which within-vessel changes in efficiency are common. Two model-fitting strategies were compared. The predictive strategy focused on maximizing the explained variance, and the estimation strategy on finding realistic coefficients for important components of changing catchability. Realistic values could not always be obtained, because the regression factors were not orthogonal, and data on the presence of technology were sometimes unreliable or systematically incomplete. It was not possible to separate fishing power from abundance by analysing logbook data alone; it was necessary to incorporate external information within the standardization model. Therefore, the resultant estimation models incorporated external information and expert knowledge by offsets. There was no single best estimation model. Instead, a series of models provided an envelope of possible changes in relative fishing power and prawn abundance since 1970. Compared with the prediction models, the estimation models revealed different trends in relative fishing power and relative abundance.

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Procedural Exposure Analysis of Logbook Data of A Government Surgeon for One Year Period

New Indian Journal of Surgery ◽

10.21088/nijs.0976.4747.9618.17 ◽

2018 ◽

Vol 9 (6) ◽

pp. 787-790

Author(s):

Kiruthika Dhakshinamoorthy ◽

Keyword(s):

Exposure Analysis ◽

One Year ◽

Logbook Data

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Seasonal bathymetric distributions of three coastal flatfishes: Estimation from logbook data for trawl and gillnet fisheries

Fisheries Research ◽

10.1016/j.fishres.2020.105733 ◽

2021 ◽

Vol 233 ◽

pp. 105733 ◽

Cited By ~ 1

Author(s):

Takeshi Tomiyama ◽

Manabu Yamada ◽

Akibumi Yamanobe ◽

Yutaka Kurita

Keyword(s):

Logbook Data

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VMSbase: An R-Package for VMS and Logbook Data Management and Analysis in Fisheries Ecology

PLoS ONE ◽

10.1371/journal.pone.0100195 ◽

2014 ◽

Vol 9 (6) ◽

pp. e100195 ◽

Cited By ~ 43

Author(s):

Tommaso Russo ◽

Lorenzo D'Andrea ◽

Antonio Parisi ◽

Stefano Cataudella

Keyword(s):

Data Management ◽

R Package ◽

Fisheries Ecology ◽

Logbook Data

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Stalked barnacle (Pollicipes pollicipes) harvesting in the Berlengas Nature Reserve, Portugal: temporal variation and validation of logbook data

ICES Journal of Marine Science ◽

10.1093/icesjms/fsp226 ◽

2009 ◽

Vol 67 (1) ◽

pp. 19-25 ◽

Cited By ~ 17

Author(s):

David Jacinto ◽

Teresa Cruz ◽

Teresa Silva ◽

João J. Castro

Keyword(s):

Temporal Variation ◽

Nature Reserve ◽

Marine Protected Area ◽

Temporal Patterns ◽

Fishing Effort ◽

Tidal Range ◽

Systematic Bias ◽

Pollicipes Pollicipes ◽

Specific Regulation ◽

Logbook Data

Abstract Jacinto, D., Cruz, T., Silva, T., and Castro, J. J. 2010. Stalked barnacle (Pollicipes pollicipes) harvesting in the Berlengas Nature Reserve, Portugal: temporal variation and validation of logbook data. – ICES Journal of Marine Science, 67: 19–25. Stalked barnacle (Pollicipes pollicipes) exploitation at the Berlengas Nature Reserve, Portugal, by professional harvesters has been subject to specific regulation since 2000. The only available information on barnacle exploitation there comes from catch reports (logbooks) provided by the harvesters. We evaluated the quality of the logbook information, described the temporal patterns of P. pollicipes fishing effort from 2000 to 2006 based on the logbook data, and modelled the daily fishing effort in relation to variability in oceanographic conditions. Results suggest different levels of reliability for the information contained in the logbooks: (i) information on the date of harvest seems to be reliable because 83% of the observed harvest dates were also declared; (ii) information on the quantity harvested shows a large discrepancy (mean = 31.8%) between declared and observed amounts, but we believe it can be used to analyse temporal patterns of exploitation, because there was no systematic bias (under- and overreporting was to the same extent). The total quantity of barnacles harvested between 2000 and 2006 (∼16 t year−1) was closely related to the effort applied. Daily harvesting effort was considered a function of two predictive variables (significant wave height and tidal range) and of their interaction. Neither the harvesting activity nor the resource itself seems to be at risk of collapse if such levels of pressure are maintained, but efforts should be made to increase surveillance and monitoring within the marine protected area.

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Variation in geographic stock area, catchability, and natural mortality of ocean shrimp (Pandalus jordani): some new evidence for a trophic interaction with Pacific hake (Merluccius productus)

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f95-100 ◽

1995 ◽

Vol 52 (5) ◽

pp. 1018-1029 ◽

Cited By ~ 17

Author(s):

Robert W. Hannah

Keyword(s):

Mortality Rates ◽

Fishing Effort ◽

Trophic Interaction ◽

Natural Mortality ◽

Commercial Catch ◽

Merluccius Productus ◽

Shrimp Abundance ◽

New Evidence ◽

Incorrect Information ◽

Logbook Data

Interannual variation in geographic stock area, catchability, and natural mortality of age 2 ocean shrimp (Pandalus jordani) was investigated for the years 1980–1990, using commercial catch and logbook data. Stock area changed gradually from 1980–1990, but showed wide variation, demonstrating that an assumption of constant catchability is not valid for ocean shrimp. Stock area was positively correlated with total catch, suggesting that stock area increases roughly in proportion to shrimp abundance. The time series of fishing effort and effort per unit stock area were quite different, showing that fishing effort probably gives incorrect information on time trends in ocean shrimp fishing mortality. Natural mortality rates varied widely over the study period also and were positively correlated with the abundance of age 2+ Pacific hake (Merluccius productus), a known shrimp predator. The best correlations were between natural mortality rates and the number of age 2–7 Pacific hake. Hake abundance indices that included only age 3+ fish were not significantly correlated with shrimp natural mortality rates, suggesting that if a trophic interaction exists between these two species, it may be influenced by hake recruitment events.

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Influence of fleet renewal and trawl development on landings per unit effort of the Danish northern shrimp (Pandalus borealis) fishery

ICES Journal of Marine Science ◽

10.1093/icesjms/fsq141 ◽

2010 ◽

Vol 68 (1) ◽

pp. 26-31 ◽

Cited By ~ 13

Author(s):

Ole Ritzau Eigaard ◽

Sten Munch-Petersen

Keyword(s):

Time Series ◽

Pandalus Borealis ◽

Northern Shrimp ◽

Unit Effort ◽

Generalized Linear Modelling ◽

Stock Assessments ◽

Order Books ◽

The Relationship ◽

Logbook Data ◽

Engine Power

Abstract Eigaard, O. R., and Munch-Petersen, S. 2011. Influence of fleet renewal and trawl development on landings per unit effort of the Danish northern shrimp (Pandalus borealis) fishery. – ICES Journal of Marine Science, 68: 26–31. Recent stock assessments of the Pandalus stock in the Skagerrak (ICES Division IIIa) and the Norwegian Deep (Division IVa east) have relied largely on a time-series of landings per unit effort (lpue) calculated from Danish logbook data. Because of fleet renewal and trawl-size changes, the relationship between nominal effort data as recorded in logbooks (days fishing) and effective effort is likely to have changed, so to standardize the nominal lpue time-series, trawl-size development has been taken into account using generalized linear modelling. As logbooks do not provide trawl-size information, this standardization was made possible by retrieving technical trawl and vessel data from industry order books. These data demonstrated an approximately linear relationship between vessel engine power and Pandalus trawl size, so validated the use of vessel horsepower from the logbooks as a proxy for an unknown trawl size. Standardized lpue time-series for the past 20 years indicated a lesser increase in stock size than nominal lpue, the modelling results demonstrating that vessel lpue increased by 9.5% with each 100 hp of engine power.

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Mixed-Species Yield-per-Recruit Simulations of the Effect of Seasonal Closure on a Central Queensland Coastal Prawn Trawling Ground

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f94-100 ◽

1994 ◽

Vol 51 (5) ◽

pp. 998-1011 ◽

Cited By ~ 7

Author(s):

N. Gribble ◽

M. Dredge

Keyword(s):

Field Studies ◽

Fishing Mortality ◽

Economic Gain ◽

Mixed Species ◽

Direct Benefit ◽

Reduced Costs ◽

Effect On Yield ◽

Yield Per Recruit ◽

Positive Effect ◽

Logbook Data

An assessment of the effect of seasonal closure on the central Queensland coastal prawn trawling grounds was carried out by mixed-species yield-per-recruit simulations of the fishery based on parameters determined from field studies and analysis of logbook data. Under a conventional scenario of constant fishing mortality, simulations suggest little positive effect on yield to be achieved from closures of up to 15 wk in duration. Economic gain would have to be made via reduced costs during the closure, rather than through increased value of the postclosure yield. Logbook data clearly showed that the fishery underwent a heavy pulse of effort, immediately after the fishing season opened. Nonlocal boats had entered the fishery to take advantage of the prawns available. Using this more realistic regime of fishing mortality, simulations suggest a significant increase in yield and value of catch. The increase was caused by boosted exploitation rates of the stocks and was determined by the magnitude of the effort pulse rather than as a direct benefit of the closure.

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