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Low-Emission Beef Production In The Southern Rangelands Of Western Australia: An Analysis Of Herd Structure And Stocking Rate Experiencing Droughts, Christophe D'Abbadie

Animal Production and Livestock Research Articles

Reconciling profitable cattle production with rangeland health and reduced emissions is a key challenge in the southern rangelands of Western Australia (WA). Stocking rate and herd structure selection are crucial decisions to achieve this balance. This study assessed the emission profiles of three contrasting herd structures (weaner production, live export, and slaughter production), and three stocking rates within a herd–carbon accounting modelling framework. The analysis considers the impact of varying drought frequencies on these cattle production systems. Herd models were developed for the semiarid southern WA rangelands. Stocking rates were set at 100%, 80% and 66% of the government recommended …

An Assessment Of Dingo Ancestry In Camp Dogs In Western Australia, Tracey L. Kreplins, Danielle Stephens, N Laing, C Oskam

Biosecurity Research Articles

Hybridisation between Australian dingoes and domestic dogs is a controversial area of interest and research. An ongoing canine sterilisation programme in rural and remote Western Australia provided an opportunity to assess the dingo ancestry of camp dogs and opportunities for hybridisation. Blood samples were collected from 345 individual community dogs at 21 locations. Dogs were screened using 23 microsatellite loci and ancestry percentage assigned using an iterative Bayesian assignment algorithm. A single individual was a dingo, 96% were domestic dogs and 3.5% were hybrids. Camp dog and dingo hybridisation in these areas is of little concern in terms of conserving …

Density-Dependence Inside A Marine Protected Area Increases Natural Mortality And Stunts The Growth Of A Spiny Lobster, Simon De Lestang, Emma Jade Tuffley

Fisheries Research Articles

Sustainable fisheries management often requires the modelling of stocks under unfished conditions, when the influence of population densities on animal growth and mortality can be substantial. This can be especially true for species such as spiny rock lobster, which are very habitat specific. Using western rock lobster (Panulirus cygnus) tag-recapture data from adjacent and similar fished and unfished areas, the key life history parameters of natural mortality and growth were examined and compared under different population density scenarios. In an area representative of virgin biomass levels, lobsters exhibited reduced growth rates and a substantially higher rate of natural mortality …

Ecological Risk Assessment For The Western Australian Sea Cucumber Resource, Kimberley A. Smith, Cameron Desfosses, Dave Murphy, Amie Steele, Lachlan W. Strain

Fisheries research reports

In April 2024, the Department of Primary Industries and Regional Development (Department) convened an ecological risk assessment (ERA) of the fisheries that access the Western Australian Sea Cucumber Resource, which comprises a range of species from the class Holothuroidea. This document contains background information used to support the ERA risk scoring process, along with the scores from the workshop and a summary of the workshop discussions that were relevant to the scoring. This includes an overview of commercial fisheries that access the Resource, focusing primarily on the WA Sea Cucumber Fishery, and one fishing authorisation issued under the Aboriginal Community …

Microplastic Extraction From Digestive Tracts Of Large Decapods, Katrina Bornt, Kathryn Linge, Jason How, Simon De Lestang, Renae Hovey, Tim J. Langlois

Fisheries Research Articles

The reliable quantification of microplastic contamination in chitinous organisms requires validated methods to remove interfering complex organic and inorganic material. This study trialled KOH, H2O2 and HNO3 digestion methods on the digestive tracts of two large decapods (Panulirus cygnus and Portunus armatus) to validate a protocol that facilitates reliable microplastic extraction. KOH digestion provided the best recovery (>95 %) of all polymers (e.g. polyamide, polyethylene, polyethylene terephthalate, polypropylene, polystyrene and polyvinyl chloride), with the lowest impact to their physical morphology and chemical spectra. While HNO3, and HNO3 + H2O2 treatments were more effective at digesting chitin, they …

Revealing The Impact Of Spatial Bias In Survey Design For Habitat Mapping: A Tale Of Two Sampling Designs, Stanley Mastrantonis, Tim J. Langlois, Ben Radford, Claude Spencer, Simon De Lestang, Sharyn Hickey

Fisheries Research Articles

Submerged aquatic vegetation, referring to benthic macroalgae and plants that obligately grow underwater, are critical components of marine ecosystems and are frequently found to provide preferential recruitment habitats. The mapping and monitoring of aquatic vegetation through remote sensing and machine learning is becoming an important aspect of managing coastal environments at scale. Accurate mapping and monitoring require robust sampling and occurrence data to assess predictive error and quantify submerged vegetation extents. The form of ground truthing survey design (preferential, random, grid-based or spatially balanced) could significantly influence predictive model outcomes and the overall accuracy of mapping and monitoring. Here, we …

What Is The Best Fit For Electric Weed Control In Australia?, Miranda J. Slaven, Catherine Borger

Experimental Summaries - Plant Research

Electric weed control is a non-chemical weed management alternative that will apply to a range of agricultural systems. The current project assessed electric weed control via the continuous electrode-plant contact method (using a Zasso™ XPower).

A wide range of field trials in 2022 and 2023 investigated weed control efficiency, suitability of electric weed control for fence line control of glyphosate-resistant annual ryegrass (Lolium rigidum Gaud.), use for crop topping, fire risk, damage to the soil biota, or use for inter-row weed control in vineyards or lupin crops. Broadleaf weeds were controlled more effectively than grass weeds with electric weed …

Estimation Of Effective Number Of Breeders And Effective Population Size In An Abundant And Heavily Exploited Marine Teleost, Andrea Bertram, Justin Bell, Chris Brauer, David Fairclough, Paul Hamer, Jonathan Sandoval-Castillo, Maren Wellenreuther, Luciano B. Beheregaray

Fisheries Research Articles

Obtaining reliable estimates of the effective number of breeders (Nb) and generational effective population size (Ne) for fishery-important species is challenging because they are often iteroparous and highly abundant, which can lead to bias and imprecision. However, recent advances in understanding of these parameters, as well as the development of bias correction methods, have improved the capacity to generate reliable estimates. We utilized samples of both single-cohort young of the year and mixed-age adults from two geographically and genetically isolated stocks of the Australasian snapper (Chrysophrys auratus) to investigate the feasibility of generating reliable Nb and Ne estimates for a …

Boom, Shake The Room: Seismic Surveys Affect Behaviour And Survival Of Western Rock Lobster, Simon De Lestang, Jason How, Kelvin Rushworth, Christine Erbe

Fisheries Research Articles

Seismic studies are conducted to investigate subterranean structures for, among other things, indications of petroleum and mineral deposits. Within the marine environment, these studies use sub-surface airguns to create powerful sound waves that penetrate the substrate, with their variable reflection time and strength being used to model seabed densities, structure, and composition. There is a growing body of work examining the effects of seismic surveys on marine fauna, primarily marine mammals and to a lesser extent fishes and invertebrates. Recently published studies on the southern rock lobster have shown these intense sound waves can affect lobster physiology and short-term behaviour. …

Agricultural Groundcover Update April 2024, Justin Laycock

Natural resources published reports

• In April, over 12% (1,876,000 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 1.5% (238,900 ha) of arable land had a high to very high risk of wind erosion because groundcover was less than 30%.

Agricultural Groundcover Update May 2024, Justin Laycock

Natural resources published reports

• In 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.

Rain And Potential Evapotranspiration Are The Main Drivers Of Yield For Wheat And Barley In Southern Australia: Insights From 12 Years Of National Variety Trials, Edward G. Barrett-Lennard, Nicholas George, Mario D'Antuono, Karen W. Holmes, Phillip R. Ward

Grain and Other Field Crops Research Articles

Context
Water is widely assumed to be the factor most limiting the growth of annual crops in rainfed environments, but this is rarely tested at sub-continental scale. Aims
Our study aimed to determine the key environmental and management variables influencing the yield of wheat and barley in the grain-production regions of southern Australia, using data from National Variety Trials. Methods
We used generalised additive models to determine the importance of climatic and management variables on wheat and barley grain yield. We determined the effects of the best one, two or three variables and their interactions. Key results
The aridity index, …

Heavy Steers And Heifers Run At Low Stocking Rates Enhance Drought Resilience In A Pastoral Region Of Australia, Christophe D'Abbadie, Ross Kingwell, Philip E. Vercoe, Bradley Plunkett, Alan Peggs

Animal Production and Livestock Research Articles

CONTEXT

The semi-arid mulga lands of the Southern Rangelands of Western Australia experience frequent droughts. Maintaining a profitable animal grazing enterprise whilst preserving rangeland condition requires selecting an appropriate stocking rate and herd structure.

OBJECTIVE

We construct and apply bioeconomic models of beef enterprises for the semi-arid Southern Rangelands of Western Australia, to assess the profitability and relative riskiness of three different livestock production systems and three different stocking rates when exposed to different frequencies of drought.

METHODS

We construct bio-economic models of herd structures that separately focus on producing either: (i) 200 kg heifers and 210 kg steers (ii) …

Including Methane Emissions From Agricultural Ponds In National Greenhouse Gas Inventories, Martino E. Malerba, Tertius De Kluyver, Nicholas J. Wright, Odebiri Omosalewa, Peter I. Macreadie

Climate Science Research Articles

Agricultural ponds are a significant source of greenhouse gases, contributing to the ongoing challenge of anthropogenic climate change. Nations are encouraged to account for these emissions in their national greenhouse gas inventory reports. We present a remote sensing approach using open-access satellite imagery to estimate total methane emissions from agricultural ponds that account for (1) monthly fluctuations in the surface area of individual ponds, (2) rates of historical accumulation of agricultural ponds, and (3) the temperature dependence of methane emissions. As a case study, we used this method to inform the 2024 National Greenhouse Gas Inventory reports submitted by the …

West Coast Rock Lobster Resource Harvest Strategy, Department Of Primary Industries And Regional Development, Western Australia

Fisheries management papers

Harvest strategies for Western Australia’s (WA) aquatic resources are formal documents developed by the Department of Primary Industries and Regional Development (DPIRD, the Department) to support decision-making processes that ensure the outcomes are consistent with the principles of Ecologically Sustainable Development (ESD; Fletcher 2002a) and Ecosystem Based Fisheries Management (EBFM; Fletcher et al. 2012). Harvest strategies are a key component of all contemporary fishery management systems and a requirement for certification under the Marine Stewardship Council (MSC). The objectives of ESD are reflected in the objectives of the Fish Resources Management Act 1994 (FRMA) and the Aquatic Resources Management Act …

Consultation Summary For Proposed Declared Pest Rates 2024/2025, Department Of Primary Industries And Regional Development, Western Australia

Biosecurity published reports

Before determining a rate, the Minister for Agriculture and Food is required to consult with owners of the land to be rated, as described in the Biosecurity and Agriculture Management (Declared Pest Account) Regulations 2014 (the Regulations).

The annual process for consultation enables the Department of Primary Industries and Regional Development (DPIRD) to gauge landholder perception on the proposed Declared Pest Rate (DPR) in accordance with the Regulations.

Agricultural Groundcover Update March 2024, Justin Laycock

Natural resources published reports

• In March, over 10% (1,577,000 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.

• The northern grainbelt had the highest risk of wind erosion and over 20% of this farmland had inadequate groundcover.

• About 1.3% (191,000 ha) of arable land had a high to very high risk of wind erosion because groundcover was less than 30%.

Sheep And Goat Industry Funding Scheme Annual Report 2022/2023, Department Of Primary Industries And Regional Development, Western Australia

Biosecurity published reports

The Sheep and Goat Industry Funding Scheme (IFS) has been operating since 2010 to address biosecurity threats relevant to the Western Australian (WA) sheep and goat industry. The Scheme was established by regulation under the Biosecurity and Agriculture Management Act 2007 to enable sheep and goat producers to identify pest and disease priorities at a whole-of-industry level and raise funds for activities to address these priorities.

There are currently three Industry Funding Schemes in operation. In addition to the Sheep and Goat IFS, there is a Cattle IFS and a Grains, Seeds and Hay IFS. The three IFSs operate in …

Agricultural Groundcover Update February 2024, Justin Laycock

Natural resources published reports

• About 92% of the grainbelt had adequate (more than 50%) vegetative groundcover to prevent wind erosion in February 2024.

• Nearly 8% of the grainbelt (1,193,400 ha) had less than 50% groundcover, which is inadequate to prevent wind erosion.

• The northern grainbelt had the highest risk of wind erosion and 16.5% of this farmland had inadequate groundcover.

• Less than 0.7% of the grainbelt had a high to very high risk of wind erosion because groundcover was less than 30%.

Procedures For Rangeland Condition Assessment In The Pilbara And Southern Rangelands 2022, Department Of Primary Industries And Regional Development

Natural resources published reports

To define the procedures used in 2022 by the Department of Primary Industries and Regional Development (DPIRD) to complete rangeland condition assessment (RCA) in the Pilbara and southern rangelands region which has predominantly shrub-based pastures. For the rest of the pastoral estate, DPIRD uses the Procedures for RCA in the Kimberley which has grass pastures.

RCA is the process DPIRD uses to make systematic, lease level assessment of rangeland. Rangeland condition considers both the condition of pastures (as defined in the Pasture condition and management guide for the Pilbara rangelands or Southern rangelands pasture condition and management guides) and soils …

Grains, Seeds And Hay Industry Funding Scheme Annual Report 2022/2023, Department Of Primary Industries And Regional Development, Western Australia

Biosecurity published reports

The Grains, Seeds and Hay Industry Funding Scheme (IFS) has been operating since 2010 to address biosecurity threats relevant to Western Australia’s (WA) grains, seeds and hay industry. The Scheme was established under the Biosecurity and Agriculture Management Act 2007 to enable growers to identify the pest and disease priorities at a whole-of-industry level and raise funds for activities to address these priorities.

There are currently three Industry Funding Schemes in operation. In addition to the Grains, Seeds and Hay IFS, there is a Cattle IFS and a Sheep and Goat IFS. The three IFSs operate in a similar manner. …

Cattle Industry Funding Scheme Annual Report 2022/2023, Department Of Primary Industries And Regional Development, Western Australia

Biosecurity published reports

In June 2010 the Cattle Industry Funding Scheme (IFS) was introduced to address biosecurity threats relevant to the Western Australian (WA) cattle industry. The Scheme was established under the Biosecurity and Agriculture Management Act 2007 to enable cattle producers to identify the pest and disease priorities at a whole-of-industry level and to raise funds for activities to address these priorities.

There are currently three Industry Funding Schemes in operation. In addition to the Cattle IFS, there is a Sheep and Goat IFS and a Grains, Seeds and Hay IFS. The three IFSs operate in a similar manner.

The purpose of …

Ecological Risk Assessment For The Western Australian Cephalopod Resource, Cameron J. Desfosses, Kimberley A. Smith, Lachlan W.S. Strain, Dave Murphy, Keyley Hogan-West, Daniel Yeoh, Shannon Burchert, Linda Wiberg, Bec Oliver, Brett M. Crisafulli, Gabby E. Mitsopoulos

Fisheries research reports

On 27 October 2023, the Department of Primary Industries and Regional Development (DPIRD, Department) convened an ecological risk assessment (ERA) of the fisheries that access the statewide Cephalopod Resource (Resource), which comprises a range of octopus, squid and cuttlefish species. This document contains the background information used to support the ERA risk scoring process, and a summary of the workshop discussions that were relevant to the risk scoring. The background information includes an overview of Western Australian commercial fisheries that access the Resource, focusing primarily on the Octopus Interim Managed Fishery (OIMF), Cockburn Sound Line and Pot Managed Fishery (CSLPMF), …

Ecological Risk Assessment For The Western Australian Large Pelagic Fish Resource, Kimberley A. Smith, Paul Lewis, Kendra Travaille, Brett M. Crisafulli, Liv Rynvis, Gabby E. Mitsopoulos

Fisheries research reports

In December 2023, the Department of Primary Industries and Regional Development (DPIRD, the Department) convened an ecological risk assessment (ERA) of the fisheries that access the Statewide Large Pelagic Fish Resource (Resource). This Resource comprises a range of tropical and temperate species including mackerels, billfish, kingfish, cobia, mahi mahi and tunas. This document contains the background information used to support the ERA risk scoring process, scoring from the workshop and a summary of the workshop discussions that were relevant to the risk scoring. This includes an overview of Western Australian commercial fisheries that access the Resource, with a focus on …

Procedures For Rangeland Condition Assessment In The Kimberley 2022, Department Of Primary Industries And Regional Development

Natural resources published reports

This report defines the procedures used in 2022 by the Department of Primary Industries and Regional Development (DPIRD) to complete rangeland condition assessment (RCA) in the Kimberley region which has grass-based pastures. For the rest of the pastoral estate, DPIRD uses the Procedures for RCA in the Pilbara and southern rangelands which have predominantly shrub pastures.

RCA is the process DPIRD uses to make systematic, lease-level assessment of rangeland. Rangeland condition considers both the condition of pastures (as defined in the Pasture condition guide for the Kimberley, Ryan et al. 2013) and soils as determined by erosion, using the …

Metropolitan Monitoring Program 2023, Alissa C. Tate, Lucy J. Rudd, Claire B. Smallwood, Karina L. Ryan

Fisheries research reports

Annual 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 …

Variations In Life-History Traits In Exploited And Unexploited Populations Of Perth Herring (Nematalosa Vlaminghi): Evidence For Density-Dependent Growth?, Kimberley A. Smith, Sybrand Alexander Hesp, Peter Graham Coulson

Fisheries Research Articles

Results supported the hypothesis of faster growth in exploited populations because of density-dependent processes. Environmental factors may also have contributed to trait differences between populations.

Long Term Sustainable Use Of Demersal Gillnet And Demersal Longline In Western Australia’S Temperate Shark Fisheries - Fisheries Research Report 340, Matias Braccini, Jack Parker, Daniela Waltrick, Maddison Watt, Nick Blay, Clinton Syers

Fisheries research reports

The Temperate Demersal Gillnet and Demersal Longline Fisheries (TDGDLF) are one of the main commercial shark fisheries in Australia. Most fishers in the TDGDLF use demersal gillnets to target sharks with scalefish taken in smaller amounts. Demersal longlines are also permitted but are not widely used. Demersal gillnets are size selective, but they do not necessarily discriminate among species, catching target and non-target species.

The Western Australian Fishing Industry Council (WAFIC) received funding as part of the Australian Government’s Our Marine Parks Grants Program to undertake research on the TDGDLF. This project was administered under the direction of a steering …

Assessment Of The Status Of The Pilbara Demersal Scalefish Resource, Corey Wakefield, Ainslie Denham, Fabian Trinnie, Sybrand A. Hesp, Rachel Marks, Dion Boddington, Stephen J. Newman

Fisheries research reports

Executive 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.

Agricultural Groundcover Update January 2024, Justin Laycock

Natural resources published reports

Summary

• About 94% of the grainbelt had adequate (more than 50%) vegetative groundcover to prevent wind erosion in January 2024.
• In the northern half of the grainbelt, a larger-than-average area has 51–60% groundcover, which is expected to decrease to below 50% over the coming months.
• Just under 6% of the grainbelt (855,000 ha) had less than 50% groundcover, which is inadequate to prevent wind erosion. West Midlands Ag Soil Zone had the highest risk of wind erosion and 14.5% of this farmland had inadequate groundcover.
• Less than 0.5% of the grainbelt had a high to very high risk of wind …