COLIN NICHOL takes up the cause of some struggling plants at Bibra Lake.
COCKBURN council should be commended for its excellent care of parks and gardens in its charge and particularly the area of Bibra Lake Reserve.
It’s well used and well cared for. We should trust council’s expertise in this field; with some exceptions they have been good caretakers of the city’s public spaces.
One of those exceptions concerns the success rate of revegetation along the lake shore areas. There are plenty of examples of past successful plantings but a recent walk around raises questions about more recent ones.
Of about 450 plantings counted inside cardboard protectors, along the western foreshore of Bibra Lake, including the vicinity of the jetty, (Bibra Lake Pier or Bibra Lake Turtle Cages section and ‘beach’), some 140 were found to survive, a success rate of only about 30 per cent.
Cockburn council’s head of sustainability and environment Chris Beaton, protests a more desirable outcome. He states the area was revegetated with 590 plants in 2021and results of independent monitoring in 2022 showed a survival rate of 85 per cent.
That is a very high success rate, so it must depend upon where you look. Presumably watering and care routines are in place for that jetty area; no information was provided on that.
Parts of that stretch has been largely left for turtle nesting which explains the bare patches.
Those regimented-like ranks of individual plantings on the northern side of the lake boundary, on Hope Road, corner of and just along from Progress Drive, look hopeful at first sight.
Spread across what is quaintly called Turtle Corner, they present what seems to be a sward of green, but on closer examination reveal themselves to apparently be mostly dead.
Of the hundreds, a walk around reveals barely one in ten survives amongst the intensive plantings across that expanse. That encouraging green is their surrounding plastic protectors, not the plants.
A plant failure rate of 70 per cent in some sections and 90 per cent in others is out of kilter with more like the approximate 30 per cent or so research turns up.
Hopefully some are late starters, or reluctant seeds.
In response, the City explains that, “in 2022, 5,000 seedlings were planted and are currently being monitored and watered.
“Current estimates of survival are 70 per cent, with final data available in May. Planning is in place for more revegetation, including infill plantings, this winter. The Rehabilitating Roe 8 project will continue to focus efforts on improving the visual and environmental amenity at Turtle Corner”.
This is a big task and represents a second attempt, after the depredations of Roe 8 bulldozing in that area.
Council backgrounds the story: “This area was first revegetated in winter 2021 as part of the Rehabilitating Roe 8 project. In that year, survival of seedlings at Turtle Corner was well below expectations due to the use of an alternative technique that did not work well with soil conditions on site”. (Surely tests had been done?).
“Record summer temperatures in Perth also took their toll”.
So, for now it seems it’s a case of watch and wait. Let’s hope enough of the struggling surviving plants hang in until the next rain.