Inquiry Into Ecosystem Decline in Victoria

LC EPC Inquiry into Ecosystem Decline in Victoria Submission 100 Inquiry into Ecosystem Decline in riverside woodland each spring, to follow up the major project, and that is very impressive. Victoria Pre-Europeans, there was a significant population of The extent of the decline of Victoria’s biodiversity Manna Gum in the area, but the last big old tree died Vegetation: trees and collapsed five years ago, so my group has planted about 10 as the start of an effort to reintroduce this In 1993 Randall Robinson was employed by Heidel- species. berg Council to develop a flora species list for Wilson Reserve, Ivanhoe East. He identified 172 species, of Shrubs which 101 were weeds, some of them very minor but The pre-European landscape in Ivanhoe included many of them very serious threats to the riverside about 10 shrub species (up to 10 m tall), but after habitats. In the 27 years since then, especially since many decades of the Yarra’s north bank being the council amalgamations in 1996, Banyule Council devoted to dairy farming, to the 1930s, only two have has somewhat increased its commitment to habitat survived: Tree Violet and Prickly Currant Bush, both management and restoration. But very large parts of of which are super-abundant, far more than would be the Yarra riverside environment within Banyule are the case in a healthy mixed-species ecosystem. So my not managed at all and Banyule has made it clear it Friends group has, among other things, planted has no intention of managing it. hundreds of shrub seedlings of the species that went The unmanaged sections are as a result overwhelmed missing: Blackwood wattle, Prickly Moses wattle, by a variety of weed species: trees, shrubs, ground- Hazel pomaderris, Victorian Christmas Bush, Hop covers, grasses, climbing creepers. Goodenia, River Bottlebrush, Hempbush. Robinson’s list includes 26 tree species, of which 20 One quite rare species along the Yarra, Muttonwood, are weed species, several of them very abundant and has a little-known population within the area we look widespread throughout the reserve, all reproducing after. It has been weeded at ground level several times copiously. and the colony censused – currently about 100 stems, varying from 2 x 10-metre old parent trees, down to One species Robinson omitted was Box Elder, Acer small seedlings recently germinated. Several have negundo, of which there are about 20-30 trees on one been planted at odd places, and Melbourne Water peninsula protruding into the Yarra. Last spring I planted about 80 of them in 6 beds in 2011 after a pulled out 32,000 seedlings of this species over nasty accident during their major woody weed blitz. several weeks from that small peninsula area – it, and All are doing well and are visited at least annually – several other copiously reproducing tree weeds can several of the beds are very well managed by the easily overwhelm the area with exotic species and Melbourne Water teams and I look after the others, all out-compete the indigenous species. of which have produced a significant number of new Almost every day while out in the reserve and its seedlings as a result of good weed control. Banyule surrounding areas, weeding, I pull out seedlings of has contributed nothing to this effort, as the beds are Glossy Privet, Box Elder, Desert Ash, Tree Tobacco, all outside the area they have decided to maintain Madeira Wintercherry, less often Mirror Bush. Had I (several are on the Yarra’s south bank in Boroon- not been removing seedlings, there would now be a dara’s territory, so are not Banyule’s responsibility). far greater abundance of these serious weed species in Ground flora: grasses, herbs the area. The reserve was created in the 1920s out of the public All the work the Banyule bushland team do is very -spirited work of a trio of local citizens: Theodore good, but their decision to abandon the large majority Eisemann, Christopher Bailey, Harry Wilson, who of the area for which they are responsible declares an raised money to purchase 1.2 km of the river frontage unwillingness to commit more resources to managing from the dairy farmer and handed it to the then their bushland. Heidelberg Council for open space. Wilson was the A decade ago, Melbourne Water invested a large local Sea-Scout leader for 41 years, arranged for amount of money and staff time in removing woody construction of a boat shed by the river and planted a weeds from Templestowe to Clifton Hill, along about decorative border of Tradescantia fluminensis around 20 km of river frontage, both banks, and that has it. This very serious weed now has invaded the entire made a very large difference. After some delay, reserve and a much wider area, and 20 years ago, money was found to invest in some revegetation and comprised virtually the entire ground cover for many shrub and tree seedlings were planted. They several kilometres of the riverbanks. Our work has sent out a team to inspect the condition of the involved a major effort to remove this often metre- deep cover and reintroduce indigenous ground covers; 1 of 17 LC EPC Inquiry into Ecosystem Decline in Victoria Submission 100 grasses and mat-forming flowering herbs. It is classified as “permitted entry” and permitted to be intensive work, requiring years of commitment to sold by nurseries. There has long been fierce resist- ongoing weed control, until the indigenous species ance by nurseries to having the more serious weed become dense and mature enough to outcompete the species banned from being sold as so many keen invasive weeds. gardeners favour them. This is a major failure of The group generally manages to attract 10-15 people environmental management on a national scale. The to working bees, and put in up to 200 plants, usually legislation needs to be changed to prohibit the sale 2-3 working bees each year, so around 600 plants. (even at Sunday markets which are also a big This is overall quite a tiny contribution to restoration problem) of a wide range of serious environmental of the riverside ecosystem, but for most of the length weeds – English Ivy, Japanese Honeysuckle, Privet, of the riverside trail we have worked on, our effort is Tree Tobacco, Madeira Wintercherry, Arum lily, not supplementing anything done by Banyule, so the Yellow Flag Iris. only work that is done has been ours. A very much One that I have not seen in residential gardens, but is greater commitment is needed, probably requiring very common in parts of the Banyule riverside land, state government funding and work force, to enlarge especially in Horseshoe billabong, is Red Inkweed this effort so it makes a substantial contribution to (Phytolacca octandra). I have put a large effort into restoration of the 1.2 km of river frontage. removing this very toxic weed, especially before its Weeds of National Significance fruit ripens, for some years, and see very little effort by Council to do anything to control this species. It This category of exceptionally serious weeds includes now seems to be spreading outside the billabong, as I 32 species, 3 of which are found in the reserve and have removed many along the nearby riverside areas riverside area we work: Blackberry (very abundant), that I patrol and try to manage. Bridal Veil Creeper (moderately often), Bitou Bush (rare), Gorse being found just outside the area, with Fauna potential to colonise inside this area. I am mainly aware of local declines in bats and frogs Banyule has a campaign most years to poison Black- and insects. berry. I find many seedlings at sites I look after and I have led 2 bat-box monitoring projects, one at Organ always dig them out. Most of these sites are never Pipes NP in Melbourne’s west, since late 1994, the visited by Banyule field staff as the areas in which I other in Ivanhoe, 10 km northeast of the CBD, since work are not actively managed by them. Feb 2005. In both projects, bat numbers peaked in The neighbouring Ivanhoe golf course (owned by 2012, and have been in marked decline since then. Banyule) at times has a good commitment to Black- The long increase in bats from 1994 to 2012 was berry control, and sometimes neglects it for years, so mainly a result of installing more bat boxes, and its fruit are spread back into the conservation areas. successful breeding of the resident bats. The subsequent decline may be due to the end of the wet Bridal Veil Creeper is found occasionally, and the years (2010-2) and recurrence of near-drought dense cluster of tubers supporting the wiry stems must conditions, reducing breeding success, or may be dug out to prevent regrowth – the worst infestation possibly be a response to the reported radical decline I have found has been in a private garden not far from in insect populations worldwide – all these bats are my home – a very large festoon of it covering several insectivores and decline in their food supply would shrubs by the front fence. cascade up the food chain. I have only found Bitou bush twice and single plants, so it is not a big issue locally. Bat numbers at Organ Pipes NP 3000 I and several other regular patrollers of the bushland 2500 trails, have had a program for years of removing Moth 2000 Vine (Kapok, Araujia sericifera), generally in areas 1500 not managed at all by the Council, and often in autumn/winter find very large vines covered in near- 1000 ripe fruit.

Load more