DPI: Coastal Residents Warned of Excavation Consequences (Australia)
The Department of Primary Industries (DPI) is warning residents of coastal communities that excavating the entrances of lakes, lagoons and intermittently opening creeks can have long lasting and severe consequences for fish and fish habitat.
DPI Director of Fisheries Compliance, Glenn Tritton, said the warning comes after a channel was recently dug out at the mouth of Bonville Creek in an attempt to open up the creek.
“A number of Sawtell residents used shovels to dredge a channel from the mouth of Bonville Creek to the ocean, which has been closed in recent months,” he said.
“Many people wrongly believe that opening creeks and lagoons can improve water quality or enhance fish recruitment, however, this is not the case.
“Similar openings of lakes, lagoons and creeks in the past have resulted in severe environmental damage.
“Opening closed creeks and lagoons to the ocean in the wrong way can lead to low dissolved oxygen levels, increased exposure, death of aquatic vegetation and large fish kills.
“In late August this occurred on Sydney’s northern beaches when a large number of fish and eels died after the entrance to Curl Curl Lagoon was opened without approval.”
Over the long term, more frequent openings can increase the rate of sand movement and lead to shifts in the structure of fringing riparian vegetation communities.
“Many of our closed creeks and lagoons maintain good water quality and are not only home to a range of aquatic life but are frequently used for swimming, water sports and fishing,” Mr Tritton said.
“It is important that there is minimal interference with these entrance barriers and that we allow the natural processes to operate where possible.
“A combination of onshore weather patterns and recent dry weather caused the Bonville creek entrance to build up with sand and the creek should re-open naturally once higher rainfalls return.”
Mr Tritton said it was illegal to harm or disturb key fish habitats along the NSW coastline without authorisation.
“Tough penalties apply of up to $110,000 for an individual or $220,000 for a corporation for the illegal dredging of waterland without a permit,” he said.
“People who witness illegal creek, lake or lagoon openings or fishing should immediately contact their local fisheries.”
Press Release, October 3, 2012