Department of Agriculture and Food Western Australia
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Livestock water requirements and water budgeting for South West Western Australia
No full textAdequate supplies of good quality stock water are just as important as feed supplies during summer, a period when feed and water quantity and quality are at their lowest in the agricultural areas of Western Australia.
Information on this page will help livestock owners to calculate a water budget – before problems develop – to complement a feed budget
Applying data-limited assessment methods to charter logbook length data
No full textMarine waters along the Western Australian coastline are characterised by low ecosystem productivity and high species diversity of fishes. With over 3,000 known species comprising estuarine, nearshore, demersal and pelagic fishes in the region, many contribute to important commercial and recreational fisheries (Lenanton et al. 1991; Molony et al. 2011; Newman et al. 2018). As it is logistically and economically infeasible to conduct intensive monitoring and high-level stock assessments of all exploited fish species in Western Australia, indicator species are used to assess the sustainability of suites of species of biological and ecological similarity, for optimal use of available resources (Newman et al. 2018).
In recent years, there has been increased demand for quantitative stock assessments of a greater number of species to meet national reporting in the Status of Australian Fish Stocks Reports (SAFS; www.fish.gov.au), used to inform Australia’s progress against UN Sustainable Development Goal 14.4.1, on the proportion of fish stocks within biological sustainable levels. The types of assessment analyses that can be applied to provide stock status estimates for a species vary depending on a range of factors including; the identified level of sustainability risk, species biology, characteristics of the fishery, data availability and level of resourcing for conducting quantitative assessments. There are five levels of stock assessment methodology of increasing complexity that are used by the Department of Primary Industries and Regional Development (DPIRD), from Level 1 (L1) which comprises a relatively simple simulation (i.e. Catch-MSY) to Level 5 (L5), which involves a dynamic, integrated stock assessment model (see Newman et al. (2023)). For many species however, no long-term reliable abundance indices and/or age composition data are available that would allow age-based equilibrium assessment approaches (L3, age-based catch curve and per recruit analysis) or dynamic assessment approaches (L4, biomass dynamics models, or L5, integrated models). Length data are available, however, for many of these species.
Compared to collecting age data, obtaining length data requires far less resourcing and thus is highly cost effective. However, the utility of length information (without catch and abundance indices) for providing stock status estimates can be limited, depending on factors such as reliability of available life history information, species biology and the dynamics of the fishery targeting the stocks of interest. As with all data used for assessment, it is also important to evaluate how representative the available length data are of the overall stock.
Unlike for commercial logbooks, Tour operator returns (charter logbooks) contain self-reported length measurements. These data, which first started being recorded in 2001/02 by charter operators from all four bioregions, provide an opportunity to raise the level of assessment for a number of fish species in Western Australia from catch only (L1) to length-based equilibrium assessment models (L3, length-based catch curve and per recruit analysis), and thereby provide more robust scientific advise for those species.
In this study, several length-based empirical analyses and models were applied to test the applicability of these methods and the available length data in charter logbooks for providing stock status information for fish species targeted by charter operators. The assessment methods include: empirical length-based indicators (Froese 2004), length-converted catch curves (Pauly 1990), length-based catch Fisheries Research Report [Western Australia] No. 331 | Page vi curve (Hesp 2023), mean length mortality estimators (Gedamke and Hoenig 2006), the length-based spawning potential ratio method (Hordyk et al. 2015a) and Bayesian biomass estimators (Froese et al. 2018)
Fallow and red deer: requirements to keep
No full textThis factsheet provides information on the requirements for keeping fallow and red deer species in Western Australia.
Fallow (Dama dama) and red deer (Cervus elaphus) are declared pests under the Biosecurity and Agriculture Management (BAM) Act 2007 in Western Australia (WA).
The department assists in preventing the establishment of deer in the wild. This means a permit is required to keep fallow and red deer in WA. Animals that escape or become feral must be recaptured or destroyed.
Small populations of feral deer occur in WA from escaped captive stock and deliberate release. Deer damage native plants, crops and plantation trees and can transmit exotic livestock diseases.
Fallow and red deer may only be kept in WA under authority of a permit to keep breed or cultivate. All other species of deer are prohibited and not permitted to be kept outside of high security facilities, such as zoological parks and scientific organisations, approved by the Minister.
Requirements for the keeping of deer have been framed to safeguard agriculture, the natural environment, and community. Permits to keep deer will include specific conditions to manage the risks that they pose to WA.
People who wish to keep deer at a particular location must apply for a permit before they obtain the animals, and a permit will only be issued when the department is satisfied (by inspection) that an applicant is able to provide conditions for the safe and secure keeping of deer.
Applicants should also be aware of the relevant industry codes of practice, guidelines, standards and animal husbandry manuals
Effective furrow sowing for water repellent soils
No full textFurrow sowing creates micro-relief, small ridges, and furrows into which water can be harvested. Sloping water repellent surfaces induce run-off, which collects at the base of the sown furrow, enhancing water entry through increased hydraulic pressure
Argentine ants
No full textArgentine ants (Linepithema humile) are small, brown, and notorious worldwide for being one of the most difficult and costly ants to control, as it can involve ongoing and repetitive use of residual, contact insecticides. The ants are established in Western Australia (WA)
Electric ant (little fire ant)
No full textThe electric ant (Wasmannia auropunctata), also known as little fire ant, is a tiny, gold-brown coloured ant, and one of the world\u27s most invasive pests. Electric ants prey on and compete with other insects and can displace large numbers of native animals, ants, and other insects.
They affect human health and lifestyle, can inflict painful stings on humans and wild and domestic animals, can blind pets, damage the environment, and have the potential to severely affect agricultural industries.
The electric ant is native to Central and South America and was first detected in Australia in 2006 in Queensland, where there are localised incursions. It is an introduced invasive ant species that is of great concern for Western Australia (WA).
Electric ants are a declared pest that is prohibited in WA under the Biosecurity and Agriculture Management (BAM) Act 2007
Managing subsurface water in WA
No full textThe Department of Primary Industries and Regional Development (DPIRD) recommends that subsurface water management is part of an integrated water and salinity program. An integrated program can help to lower water tables and alleviate problems with waterlogging, rising salinity, and infrastructure damage
Breeding ewes are worth feeding
No full textDespite potentially elevated grain prices, strong prices for meat and wool mean that Western Australian sheep farmers can confidently supplementary feed their underweight ewes in summer/autumn.
Analysis in 2019, based on then-current prices, showed it was a profitable investment to feed all ewes to maintain condition during pregnancy, and to feed low condition score single bearing ewes and low and medium condition score twin bearing ewes to gain condition.
In 2019, John Young from Farming Systems Analysis Service completed an analysis on the value of a ewe in the WA farming system. His report had some important messages for the 2020 season.
This coming summer/ autumn, the feed shortage due to dry conditions and potentially higher supplementary grain prices may tempt local farmers to underfeed their ewes,” said Mr Young. “However, farmers need to consider the cost of mismanaging ewe nutrition.”
Mr Young used 2019 prices to update the economic analysis he carried out in 2011 for Lifetime Ewe Management (LTEM), the nationally recognised course in better ewe management and lamb survival
Sheep worm control in WA
No full textEffective, sustainable control of sheep worms involves a combination of planned stock and farm management, monitoring worm burdens using faecal worm egg counts (WEC), strategic timing of drenches and the genetic selection of worm resistant sheep.
Levels of drench resistance of sheep worms in WA are some of the highest in the world and without resistance management action at individual farm level, it will continue to worsen and spread.
Although effective drench options are generally available, many sheep owners are unaware that resistance has reduced the effectiveness of worm control programs, and this can affect profitable sheep production
Decoding the decisive role of seed moisture content in physical dormancy break: filling the missing links
No full textSpecies producing seeds with a water-impermeable seed coat, i.e., physical dormancy (PY), dominate the dry tropical forests. Despite increasing interest and understanding of the germination ecology of a PY species, less is known about how PY break occurs, particularly what changes lead to the opening of the ‘water gap’. Based on the moisture conent (MC) attained, two ranges of PY may exist: shallow PY, a state with higher MC and seeds could reverse to a permeable state when the relative humidity increases; and absolute PY, a completely dry state. Here, we demonstrate that this MC variation between seeds affects preconditioning and the ‘water-gap’ opening stages. A conceptual model developed shows a strong relationship between temperature and duration, with high temperature breaking PY in seconds, but seasonal temperature fluctuations and constant temperatures require a longer time. The duration required at any conditions to break PY is purported to depend on the hydrophobic bonds of the lipids, which are likely weakened during the preconditioning, and the amount of water influences hydrolysis, leading to the ‘water-gap’ opening. We argue that the moisture content of the seeds and its interaction with biochemical compounds are a possible explanation for why only a proportion of PY seeds become permeable to water each year. Nonetheless, empirical investigations must validate these notions