Daintree to Lower Barron Fish Barrier Prioritisation project

Fish migration is an essential life-history adaptation utilised by many freshwater fish species in the Wet Tropics region’s coastal catchments.

Catchment Solutions assessing fish barriers on waterways in the Wet Tropics Qld

A comprehensive study

In 2023, Catchment Solutions partnered with Terrain NRM to conduct a comprehensive study on fish barriers within coastal catchments from the Barron to the Daintree, encompassing the Bloomfield River. The primary objective was to assess the large number of man-made barriers that prevent, delay and obstruct fish migration in the Daintree, Mossman, Mowbray, Bloomfield and Lower Barron River catchments. These barriers were evaluated based on their cumulative impact on aquatic ecosystems, fisheries resources, economy, and local communities. This study, conducted alongside the Murray and Lower Herbert Rivers Fish Barrier Prioritisation, aimed to prioritise barriers and their remediation efforts in the southern Wet Tropics region.

Daintree River Fish Barrier prioritisation identify and rank for fishway construction remediation
Fish Barriers on Avondale Creek Cattana Wetlands, Granite Creek Bloomfield River and Daintree River catchment.

Fish migration is an essential life-history adaptation utilised by many freshwater fish species in the Wet Tropics region’s coastal catchments. Migration strategies between key habitats have evolved for various purposes, including feeding, reproduction, predator avoidance, nursery habitat utilisation, genetic diversity maintenance, and population dispersal. Barriers disrupting connectivity not only affect fisheries’ productivity but also create conditions conducive to invasive pest fish species like tilapia. Importantly, around 70% of freshwater fish species in the Daintree to Lower Barron regions migrate between estuarine and freshwater environments, including iconic species such as barramundi, mangrove jack, jungle perch, tarpon, giant herring, and long-finned eels. Lesser-known species, like empire gudgeon, red scat, roman-nose goby, and the critically endangered opal cling goby (Stiphodon semoni) also rely on migration between saltwater and freshwater for their life cycles and contribute significantly to aquatic ecosystems. Remediating barriers and preserving connectivity between saltwater and freshwater is crucial for maintain freshwater fish community condition and enhancing overall aquatic ecosystem health.

Australian diadromous fish species impacted by fish barriers in our waterways
Key fish species that migrate between salt and fresh water to complete their lifecycle; Mangrove Jack, Jungle Perch, Opal Cling Goby (photo credit James Donaldson), Post-larvae Barramundi
Diadromous freshwater fish species impacted by fish barriers captured during fishway monitoring by Catchment Solutions including, mangrove jack, jungle perch, opal cling goby and post larvae barramundi
Catchment Solutions Fisheries Ecologist Matt Moore with the iconic Barramundi that requires connectivity between salt and freshwater to complete their lifecycle.


Examples of barriers identified in the project:

Top-ranking barriers

A catchment-scale river network analysis tool in GIS was employed to prioritise these barriers based on biological and geographical criteria, generating a prioritised list for on-site validation.

Fish barrier prioritisation map created by Catchment Solutions for the Daintree, Barron, Mowbray, Bloomfield rivers in Wet Tropics, north Queensland, Australia
Showing all potential fish barriers (n=1,649) identified in coastal catchments from the lower Barron to Daintree Rivers in stage 1 of the fish barrier prioritisation

Following field validation, a top 30 priority list of barriers in the northern Wet Tropics region was produced, outlining remediation options and indicative costs. The top-ranking barriers impacting the region’s fish populations and aquatic ecosystem health include:

  1. Granite Creek – Redundant Causeway – Bloomfield River catchment
  2. South Mossman River – Mossman Mill Weir – Mossman River catchment
  3. Marins Creek – Culvert Causeway – Daintree River catchment
  4. Stewart Creek – Pipe Culvert Causeway – Daintree River catchment
  5. South Mossman River – Shannonvale Rd Causeway – Mossman River catchment
Top ranking fish barriers in the Wet Tropics, Queensland, identified by Catchment Solutions at weirs and culverts in Mossman, Daintree rivers
Top 3 priority ranked fish barriers identified in the fish barrier assessment for the Daintree
fish barriers prioritised by Catchment Solutions in Wet Tropics, Queensland rivers, Australia, including weirs, road causeways and culverts
Top 4 to 6 priority ranked fish barriers identified in the fish barrier assessment in the Daintree

Catchment Solutions Fish Barrier Prioritisation Report - Daintree, Mossman & Lower Barron Catchments

Link Fish Barrier Report

After identifying and prioritising fish barriers, the goal is to appropriately remediate these structures using nature-like rock ramp fishways

rock ramp fishways or rock fish ladders designed and constructed by Catchment Solutions in Queensland, Wet tropics
Showing nature-like rock ramp fishways on 5 Mile Creek, Cardwell, Gooseponds Creek, Mackay and Murray Creek, Mt Ossa constructed to remediate fish barriers and provide aquatic connectivity.


Lagoon Creek Rock ramp Fishway constructed by Catchment Solutions completed and flowing
Lagoon Creek Fishway construction completed and flowing. Photo credit: Geoff Collins (OzFish)


Five Mile Creek Fishladder Post Construction and Flowing
Five Mile Creek Fishladder Post Construction and Flowing. Photo Credit: Geoff Collins (OzFish)