Quickup River - Powleys Road

River condition at the Powleys Road site (site code: HD25QUIC1, site reference: 6031577) on the Quickup River (a tributary of the Denmark River) was assessed in March 2020 as part of the Healthy Rivers Program (Healthy Rivers), using standard methods from the South West Index of River Condition (SWIRC). The SWIRC incorporates field and desktop data from the site and from the broader catchment. Field data collected include the following indicators, assessed over approximately a 100 m length of stream:

• Aquatic biota: fish and crayfish community information (abundance of native and exotic species across size classes, general reproductive and physical condition)
• Water quality: dissolved oxygen, temperature, specific conductivity, and pH (logged in-situ over 24 hours), as well as laboratory samples for colour, alkalinity, turbidity and nutrients
• Aquatic habitat: e.g. water depth, substrate type, presence of woody debris and detritus, type and cover of macrophytes and draping vegetation
• Physical form: channel morphology, bank slope and shape, bioconnectivity (barriers to migration of aquatic species), erosion and sedimentation
• Fringing zone: width and length of vegetation cover within the river corridor and lands immediately adjacent, structural intactness of riparian and streamside vegetation
• Hydrology: measures of flow (velocity) at representative locations (compared against data from stream gauging stations within the system)
• Local land use: descriptions of local land use types and activities (compared against land use mapping information for the catchment)

This is the first assessment of this site using the SWIRC methods. At this time no previous assessments of river ecology had been reported.

Assessments are listed below:

• 2020 – summer (18–19 March): Healthy Rivers

Other department data: Search on the site code or site reference in the Department of Water and Environmental Regulation’s Water Information Reporting (WIR) system to find data for this site and nearby sampling points (flows, surface water quality, groundwater monitoring, the department's meteorological data). See also the Bureau of Meteorology website for additional meteorological data for the area.

Six native species were recorded at this site in the March 2020 assessments, comprising three endemic* fish (nightfish, western minnow, western pygmy perch), and three endemic* crustaceans (smooth marron, koonac, a new crayfish species – see below for further information). This included some of the largest nightfish (18 cm) and western minnow (16 cm) that have been found across all assessments conducted throughout Western Australia. A pigment-free western pygmy perch was also amongst the catch. See the gallery at the bottom of the page for more images.

* these species are ‘endemic’ to south-west Western Australia, which means they are found nowhere else in the world (unless introduced)

Notably no non-native species were recorded during assessments.

Western mud minnow are expected in the subcatchment but were not recorded at this site and may be located elsewhere in the catchment. This species is listed as vulnerable under the Biodiversity Conservation Act 2016 (state, Western Australia) and is highly susceptible to salinisation, land degradation and hydrological changes due to instream barriers, water abstraction and climate change. Further investigation is required to determine the presence-absence of this species.

The new crayfish species recorded at this site was discovered through a genetic survey of crayfish in South West Western Australia undertaken by the department and Edith Cowan University (School of Science) in 2019–2020. This crayfish was recorded across the Denmark-Albany region and is similar in appearance to the restricted gilgie (Cherax crassimanus). This new species of crayfish is yet to be described, for the purpose of this summary it will be referred to as Cherax species novel.

Only fish and freshwater crustaceans (crayfish and shrimp) that typically inhabit river channels are targeted by the standard SWIRC sampling methods. However, where other species were caught and/or observed (e.g., turtles, rakali-native water rats, tadpoles), these are mentioned below in the Other aquatic fauna section.

Note: collection of fauna from inland aquatic ecosystems across Western Australia requires a license from the Department of Primary Industries and Regional Development (DPIRD) and also the Department of Biodiversity, Conservation and Attractions (DBCA). All species collected must be reported to these agencies as part of license conditions.

Although not targeted by collection methods a motorbike frog (Litoria moorei) and native bush rat (Rattus fuscipes) were recorded during March 2020 assessments.

For more information on aquatic species, please see the River Science fauna page here.