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Metropolitan Monitoring Program 2023
No full textAnnual surveys of shore- and boat-based recreational fishers within the Metropolitan zone of the West Coast bioregion provide information on human dimensions and catch-per-fisher as well as mean length and weight of key recreationally caught species. For shore-based fishers, estimates of effort, catch and harvest are also presented for key nearshore species. This information is used to support ongoing assessments for key demersal and nearshore species and review the effectiveness of fisheries managements, such as Australian Herring and Southern Garfish.
A roving creel survey of shore-based fishers was used to collect data between Ocean Reef and Point Peron (30% of coastline within the Metropolitan Zone) from February to June 2023. Estimates of fishing effort and catch therefore align with the spatio-temporal sampling frame of this survey. An access point (boat ramp) survey was used to collect data from boat-based fishers at key boat ramps between Two Rocks and Mandurah from January to July 2023. These data are considered to be representative of the entire Metropolitan zone.
The highest proportions of shore- and boat-based fishers were aged between 30–44 (36%) and 45–59 (25%) years. Shore-based fishers predominantly fished less than ten days (38%) in the previous 12-months. Most shore- (85%) and boat-based (75%) fishers resided and fished within the Perth Metropolitan area.
Median kept catch for shore-based fishers on a fishing trip was 3 fish per fisher. Australian Herring (29%), Squid (12%) and Yellowtail Scad (8%) were the most frequently kept species. Toadfish, Tarwhine and Pink Snapper were the most frequently released species by shore-based fishers. Median kept catch for boat-based fishers on a fishing trip was 1 fish per fisher. West Australian Dhufish (10%), Silver Trevally (9%) and Squid (9%) were the most frequently kept species, while Wrasses (21%), Pink Snapper (16%) and West Australian Dhufish (6%) were the most frequently released species by boat-based fishers.
Fishing effort for shore-based fishers in the Metropolitan zone was 147,062 fisher hours (95% CI 126,276–167,847) in 2023. Effort remained consistent with all previous survey years (2010, 2014–22) (i.e., the 95% confidence interval overlapped between survey years), except 2016 (194,926–382,931 fisher hours). The kept catch (all species) for shore-based fishers was 190,941 fish (95% CI 27,053–354,828) in 2023, and 144,793 fish (103,945–185,640) were released. Annual kept catch was higher than the past 5 years, although this was not significantly different.
The annual mean shore-based harvest of Australian Herring was 13.6 t (95% CI 6.6–20.7 t) in 2023 which has been steady since 2018. The annual mean harvest of Australian Herring was lower in 2023 compared with 32 t (95% CI 19.9–44.3) in 2017 and 31.1 t (95% CI 19.8–42.3) in 2010 (shorter, 3-month survey period) although this was not significantly different. The shore-based harvest of School Whiting was 0.5 t (0.1–1.1) in 2023, which was consistent with the previous 3 survey years. The shore-based harvest in 2023 for Pink Snapper (0.7 t 95% CI 0–1.9), Tailor (0.9 t 95% CI 0–3.3) and Squid (3.6 t 95% CI 1.2–6) has been consistently low since 2014
Workshop on recreational fisheries in stock assessments (WKRFSA)
No full textICES Technical Report Contributors (Editors)
Martina Scanu; Zachary Radford
Contributors (Authors)
David Curtis; Didzis Ustups; Eneko Bachiller; Estanis Mugerza; Gwladys Lambert; Hans Jakob Olesen; Ioannis Thasitis; Ivo Sics; Jonnathan White; Karina Ryan; Kieran Hyder; Kjell Nedreaas; Lennert van de Pol; Lucia Zarauz; Manos Koutrakis; Marie Storr-Paulsen; Martina Scanu; Matthew Farthing; Nicola Walker; Paul Bouch; Pia Schuchert; Sean Tracy; Simon Weltersbach; Sophy Phillips; Zachary Radford.
Executive summary
The Workshop on Recreational Fisheries in Stock Assessments (WKRFSA) aimed to establish a process for integrating recreational fisheries (RF) data into stock assessments. The workshop addressed three questions: identifying obstacles to RF inclusion, creating a decision tree for RF data inclusion and reconstruction, and establishing criteria based on data quality and catch quantity. It had three sections: assessing where RF data fits in the assessment cycle, schematizing RF data reconstruction, and discussing blockers to RF inclusion. To prioritize stocks for RF data inclusion, a productivity-susceptibility analysis (PSA) by the WGRFS is ongoing. This PSA will provide a list of species within each ecoregion where RF could impact stock sustainability levels. When a risk is identified for a stock, RF data should be included in the data-call process for consideration in the benchmark. Key blockers to RF inclusion were categorized into data issues, communication challenges, and resourcing problems. Data issues focused on quality, quantity, and consistency of the RF data. A need for better communication about RF data availability was outlined. Resourcing challenges included knowledge gaps within ICES stock roles, communication of RF-specific advice, and capacity needs for improved inclusion methods. A flowchart-based framework for integrating RF data into the stock assessment process was developed, addressing survey errors, different catch levels, and reconstructing commonly missing RF data under different scenarios. Acknowledging data limitations, the framework proposed capturing RF exploitation levels in the assessment model or as a statement in the advice only. The workshop addressed several of the blockers to inclusion of RF data into the assessment/advice cycle through identifying avenues for improved RF communication, devising methods within the framework for handling data quality, quantity, and consistency issues. However, the workshop was not able to resolve all the issues identified. Five key tasks for future development to resolve further blockers emerged: ICES supporting both stock assessment and RF communities to enhance capacity, considering a dedicated RF data coordinator role for each stock, improving communication between WGRFS and assessment WGs, compiling a priority list of species through PSA analysis, and ACOM providing standardized guidance for RF-specific advice
BEN Signage Installation Map – Shire of Augusta-Margaret River
No full textBeach Emergency Number (BEN) Signage Installation Map – Shire of Augusta-Margaret Riverhttps://library.dpird.wa.gov.au/gis_bens/1021/thumbnail.jp
All insect, weed and plant disease occurences recorded in the PestFacts WA database in 2024 from all sources. This includes data from the project\u27s surveillance activities.
No full textThe collection contains all weeds, insect and disease reports recorded in the PestFacts database during 2024 from all sources
Assessment of the status of the Pilbara Demersal Scalefish Resource
No full textExecutive Summary
For this assessment of the Pilbara Demersal Scalefish Resource (PDSR) of Western Australia, red emperor and bluespotted emperor are the indicator species used to represent the status of the resource. In addition, goldband snapper, though not an indicator species, is relatively abundant in the annual catches, particularly in deeper waters (around 100 m) and in the western Pilbara region and its status has also been assessed
Implications of big, old, fat, fecund, female fish (BOFFFFs) for the reproductive potential of a demersal teleost stock
No full textThe ‘big old fat fecund female fish’ (BOFFFF) hypothesis suggests that larger, older female fish contribute disproportionately more to the reproductive potential of a stock than smaller, younger female fish. As fishing typically differentially removes larger, mature fish, this can negatively impact reproductive potential and impair the recovery of a depleted stock. In this study, the BOFFFF hypothesis was explored quantitatively for the endemic West Australian dhufish (Glaucosoma hebraicum) by estimating the relationships between total length (TL) of females and spawning season duration, spawning frequency and oocyte size. The impacts of these size effects on estimates of reproductive potential of the G. hebraicum stock were also explored using a per-recruit analysis. Larger (900 mm TL), older mature female G. hebraicum were shown to spawn for a longer duration (six versus two months) and on more occasions (155 versus 60 times) than smaller (350 mm TL), younger mature fish, and thus these larger females have higher annual fecundity. Larger, older mature G. hebraicum also spawn, on average, significantly larger oocytes with greater estimated energy content (474.6 diameter and 0.234 J versus 379.9 and 0.140 J). Due to these size effects, reproductive output of G. hebraicum scales hyperallometrically with fish body mass, rather than isometrically. Not accounting for these size effects in per-recruit analysis resulted in higher estimates of stock reproductive potential and thus stock status. Such overestimates, if used to inform management, have the potential to result in harvest rates being set too high which, in turn, could thus affect stock sustainability
Manipulating larval rearing media to optimise mass production of the blow fly Calliphora vicina (Diptera: Calliphoridae)
No full textThe oviparous blow fly Calliphora vicina has shown potential as a managed pollinator to support honeybee (Apis mellifera) usage in Australian horticulture. A series of three laboratory-based studies reared newly hatched larvae of C. vicina on meatmeal with varying amounts of either whole egg powder, whole eggs (including shells), bran flakes, brewer\u27s yeast, fish paste or milk powder. The objective was to determine the best larval media for quick and efficient production of adult flies in a mass-rearing environment. Pure meatmeal or meatmeal with only brewer\u27s yeast added were the least productive media. Larvae fed meatmeal with either 10% or 20% whole dried egg powder had the fastest development to pupae, the highest pupation rate, the heaviest pupae and the highest subsequent adult eclosion. Larval media containing fish paste had the highest survival through to adult emergence (\u3e85%) of all the media treatments, which suggests that this ingredient is of value when mass rearing C. vicina. In addition, newly hatched larvae (n = 50) were reared on varying amounts of media (i.e., 4, 2, 1, 0.5, 0.25 and 0.125 g per larvae) to determine the minimum amount of media required to produce adults. Reductions in media per larvae resulted in smaller pupae and adults that emerged with no subsequent reduction in adult eclosion, indicating the adaptability of this fly to food deprivation. Replacing whole egg powder with whole eggs reduces the costs of rearing C. vicina larvae significantly. In order to rear 1 million adult C. vicina, these studies showed that 0.5 g of media per larvae is sufficient to produce high numbers of pupae with \u3e95% adult eclosion. Although larval development and pupation are optimal on media containing whole egg powder, its recent rapid rise in costs makes it far less economical compared with the use of discarded whole eggs from egg producers. Sourcing of seafood waste could also reduce media costs and improve production of C. vicina. The costs of each media required to realise 1 million adult C. vicina are between 1900 depending on the media ingredients
Agricultural groundcover update May 2024
No full textIn May, over 9% (1,410,000 ha) of the arable farmland in the south-west of Western Australia had less than 50% vegetative groundcover, which is inadequate to prevent wind erosion. Northern grainbelt had the highest risk of wind erosion and over 26% of this farmland had inadequate groundcover, predominantly found on landscapes known for sandy soils. About 1.3% (208,900 ha) of arable land had a high to very high risk of wind erosion because groundcover was less than 30%. Half of this land was in the West Midlands Ag Soil Zone
Bringing it all together - Turning the Dial Conference 2024
No full textJoin us for the final session of the day, where we\u27ll bring together industry experts for a dynamic panel discussion facilitated by MC Josh Byrne. Huia Adkins from GHD, Ebony Johnson from the National Retailers Association, and Nerida Kelton from the Australian Institute of Packaging will share their insights and perspectives on key themes discussed throughout the event.
During this interactive session, panelists will reflect on the day\u27s presentations and discussions, highlighting key takeaways, challenges, and opportunities for action. From sustainable packaging to circular economy thinking, attendees will gain valuable insights into how industry leaders are driving positive change within their respective sectors.
Speakers Huia Adkins, GHD, Sustainability Business Group Leader Nerida Kelton, AIP Bonnie Marshall, National Retail Association, Communications Manager, Policy team
Facilitator Josh Byrne, Josh Byrne & Associates, Directo
Weed Seed Wizard scenario - herbicide resistance in wild oats in Wagga Wagga, New South Wales
No full textThe Weed Seed Wizard is a national collaborative project that uses paddock management information to predict weed emergence and crop losses now and in the future.
The Weed Seed Wizard is a computer simulation tool that: applies to all Australian grain growing areas helps growers understand and manage weed seedbanks on their farms uses farm management records to simulate how different crop rotations, weed control techniques, irrigation, grazing and harvest management tactics can affect weed numbers, the weed seedbank and yields uses farm-specific management and site-specific weather is multi-species
See www.dpird.wa.gov.au for further information on Weed Seed Wizard.
This New South Wales scenario is set in Wagga Wagga between 2008 and 2010 and is a barley - canola - wheat rotation with wild oats and a few annual ryegrass