Environment Minister Albert Jacob, said, “the 2014 Fish Community Index showed that fish communities in the Swan and Canning rivers from Mosman Park and upstream to the Swan Valley and Kent Street Weir had improved since the mid-2000s.”
The fish index uses a range of metrics including diversity and number of fish species to evaluate the fish community as one measure of estuary health.
Other measures that contribute to an overall picture of river health include water quality, seagrass growth and distribution and a survey of foreshore conditions.
Mr Jacob ,said, “The 2014 Fish Community Index assessment for the estuary as a whole is consistent with the pattern of good-fair condition assessments in recent years,”
He further added “In total, 35 species and more than 30,825 fish were caught and released in shallow waters and 21 species and 1,601 fish were caught and returned in deeper waters by scientists.
It is important to note that the number of species caught in deeper water was consistent with those in 2012 and 2013.”
However, the number of species recorded in shallower waters in 2014 was notably higher than the 29 species recorded in the previous two years.
The Minister said the rivers, like all urban waterways, were under pressure from climate change, historical land use and development, but the fish community results showed the rivers were stable.
Adding further he said ,“This year’s results reflect high and stable salinity in the rivers, higher oxygen levels and the absence of algal blooms across much of the water way.
It’s true that some parts of the river system are healthier than others but the claim that the river is dead is just not supported by the science and monitoring.”