An environmental group is celebrating the results of a Blackadder Wetlands transition from tidal to freshwater system project, which has been a great success without the use of chemicals.
The Blackadder Woodbridge Catchment Group (BWCG) is a voluntary group that works to preserve and enhance the remnant habitat along the Blackadder and Woodbridge Creeks.
The BWCG’s project involved herbicide free weed control, community planting events and a bird survey on the Blackadder Wetland, located in Ray Marshall Park next to the Swan River.
Seven volunteers counted birds each week at the wetland over a 12-month period and the resulting data is the most comprehensive collection of annual bird data for the wetland to date.
The bird study was done to understand ecological changes at the wetland, following the construction of a weir by the City of Swan in 2012.
The study found, as a fresh water system, the wetland was a very important summer refuge for water birds in an urban setting, and up to 1000 birds per survey were counted during the study.
BWCG secretary Phil Cloran said the data would now be used as a baseline for future studies and it would inform future management of the area.
Mr Cloran said the study found the wetland provided habitat for at least 102 bird species, with 26 of those species listed as having conservation significance.
He said 12 species were observed breeding at the wetland, including three conservation category species, nankeen night heron, pink-eared duck and blue-billed duck.
“It now supports well over twice the numbers and species diversity as it did as a tidal system when BWCG last officially surveyed the site in 2000.”
Mr Coran said the wetland was gathering increasing interest from the community and the study also identified two potential sites where the addition of seats and bird hides would add to the enjoyment of the wetland.
BWCG chairman Adam Viskovich said the study was also a useful basis for future work particularly on water quality, fish, fauna and macro invertebrates.
As an added bonus, the study found less mosquito breeding took place as a freshwater system than when there were frequent incursions of salt water in summer.
Mr Viskovich said the BWCG would continue its efforts in weed control and planting of indigenous flora in the vicinity of the wetland and fortnightly bird counts would be conducted.