Friends of Deal Island
Working Bee Report 13 – 29 April 2015
Funding: The bulk of funds for this working bee came from a grant provided by the Foundation for National Parks and Wildlife for weed management and restoration of native vegetation. Some funds were also sourced from a small grant from the Wildcare Board provided through NRM North for North-east islands management. Volunteer participants contributed to travel costs and paid for food for the fortnight and accommodation on Flinders Island. In –kind support was provided by PWS Flinders Island with transport on Flinders, and use of the visitors’ house, vehicle, gas, etc. on Deal.
Objectives: The first general objectives of any weed management program must be to ensure that no new infestations establish and to conduct maintenance / follow-up weeding to support work done previously. As well, we always hope to continue to progress the program by doing some new work.
More specifically, our objectives were to:
Participants: Bob and Penny Tyson, Shirley Fish, Paul Chisholm, Ross Baguley, Phillipa Foster, and Vicky Wadley. Chris Sedevic was a last minute withdrawal due to ill health of a close relative.
Catering: The bulk of the food was ordered in advance from Walkers supermarket, with meat ordered through Ciaran the butcher. Thanks go to Sally and Rachael of Walkers for being extremely helpful as usual.
Transport: Private vehicle transport to/from homes to Launceston Airport. Sharp Airline flights to/from Flinders Island. Each paid a contribution of $100 towards the cost of transport. Boat crossings to/from Flinders Island to Deal Island were with James Luddington on Strait Lady. On our arrival at Whitemark we were met by Wayne and Cindy who transferred us and our gear to the Whitemark jetty. We and all of our gear and supplies were then transferred to Strait Lady in the zodiac due to the very low tide. After a quick smooth run with a detour to look at the back of Dover Island, we arrived at the jetty mid-afternoon. Our return to Flinders at the end of the bee was delayed by a day because of the weather, and we arrived back in Whitemark in the morning of the 28th which gave us half a day to look around. We were joined by Wayne, James and Lindsey for our end of bee pub meal. It was a smooth flight back to Launceston on the early flight on 29th April.
Caretakers: Tim and Lyn were very welcoming. They met us at the jetty to transport all the gear up to the house. They made the truck available to cart fencing materials, and Lyn joined us for several days weeding. We shared several meals and birthdays with them.
Induction, Training and Safety: Once we got to Deal, everyone was introduced to the island and the projects to be undertaken. Job safety was discussed. Job Risk Analyses were read, Material Safety Data Sheets were referred to and Personal Protection Equipment was provided and its use emphasised. We reviewed each day’s work as we went and discussed safety issues arising. Weed and native species, including rarities, were introduced as we worked.
Notes on revegetation:
The slopes down to East Cove have been the site of one of the two large infestations of sea spurge on Deal Island, and the current major focus of weed removal and subsequent rehabilitation. (The other big infestation was at Garden Cove.) The core of the 5ha East Cove infestation was fenced to exclude the wallabies, and so prevent damage done by their browsing and movement through the area. Then the mature spurge was weeded - for the first time just 12 months ago. The first generation of regrowth was removed by the working bee last November. This was a big job – seedling spurge 10 -15cm tall, in a density resembling grasses in a lawn. On this bee we returned to do the second re-weeding and luckily, the seedling density was about 90% less.
The dry period on the island leading up to November and commented on in the last report has continued, and there was even less food for the wallabies, which were in poor condition. They had not been able to get into the exclosure though, and vegetation within was dry but so much better than elsewhere. (The geese too were suffering from lack of food and we saw several fresh carcases around the residence compound area.)
As we saw last time, the differences between the vegetation and the condition of the soil inside and outside the exclusion area are dramatic, there being increasingly more vegetation within the exclosure than outside. The extensive areas covered by the green Tetragonia (bower spinach) and Rhagodia (coastal salt bush), and also by grey saltbush (Atriplex cinerea) appeared to have expanded. Sword sedge seemed to be spreading as well and there were a lot of native grasses the density of which - and other vegetation, was greater on the lower slopes. Some plants appeared to have died as result of the dry – the main species concerned being pimpernel (Anagalis arvensis) an introduced species, but useful in holding some soil.
Some indication of the scale of the effect that wallabies have on the vegetation can be seen from the smaller areas from which wallabies have been excluded. Small rectangular areas were fenced off early in the program to show the effects that grazing by wallabies has on the vegetation. These now contain vegetation 30 – 50cm tall and closely grazed where the hungry wallabies can reach. They look as if they have been carefully topiaried into three dimensional shapes. In most of these exclosures, Tetragonia and Rhagodia are the dominant species within the fence.
Outside the main exclosure, both soil and the ground cover vegetation (apart from the coast twinleaf Zygophyllum billarderei which continued to thrive) looked worn, sparse and extremely dry. Between the patches of twinleaf were large areas of bare black, loose sandy soil in which a few wall rocket, plantagos and a very few thistle rosettes could be seen. The soil was so dry that it was hygroscopic – it repelled water. Even a small amount of rain such as the falls of 1 or 2mls experienced during the bee was not absorbed but ran off the surface taking soil with it and so developing runnels. There is a potential that if heavy rain falls on very dry soils, runnels can grow and develop into erosion gullies which can be a feature of granular granitic soils. However, since the working bee, there has been some decent rain (and we hope for more) without ill effect. Seed in this bare soil will now be germinating – those of native and introduced plants (including weeds) alike. It may be a busy weed season to come.
As before, spurge was dealt with by pulling and dropping the plant on the ground to rot except for fertile material from the few seedy ones which was composted. The very few larger plants growing from established roots were cut and the stem pasted with glyphosate.
Likely places around the coastline were checked for new infestations – nothing new was revealed. Squally Cove, Little Squally Cove, ‘Indian Head Cove’ (the one west of East Cove), Pulpit Rock were all visited, and only 2 small plants were removed from Winter Cove. Time: 8 hours
Garden Cove Spurge: This was worked over first (this was the 9th reweeding since the area was first cleared. We all spent one full day there and several of the team returned again later in the bee for further sweeps. This time we really did have to look hard to find spurge and it was hard for new people to believe that so much of the area had previously been affected by such a dense and well established infestation. We think the area was covered fairly thoroughly. A few seedy plants missed last time were bagged and returned to compost in the weed drum. Each of the 15 outlying patches were checked at least twice. Time: 92 hours
East Cove Spurge: The difference in this area is amazing. The two rounds of weeding out spurge so far, has totally changed the look of the slopes around the Cove. Where sea spurge dominated the scene just over 12 months ago, natives are beginning to take over again.
We started work by weeding inside the fenced area. With everyone working, this took two days to clear, followed up with periods later in the bee. Re-weeding areas outside the fenced exclusion area was much quicker this time, but still some plants were found surprisingly high above the top fence. Time: 140 hours
Total sea spurge: 240 hours
Work continued on the removal of arums. We searched areas known to have arums in the past, with some walks taken off track in the hope of finding more. About 25 plants were removed mainly from halfway house and Telstra Corner areas. Arum sites are marked with stakes left in place for 3 years or so, and checked regularly. Stakes are removed if no regrowth is noted over 2 years. Time: 40 hours
Known sites at Garden Cove, the residence compound area, as well as the Jetty Patch and the site in the bay to the west of East Cove were all checked. Nothing found at Garden Cove, nor were any west of East Cove. But 50 or so small non seedy plants removed from the Jetty Patch. A group of ten plants which had flowered were found outside the compound downhill and nearly adjacent to the generator shed (marked with stake) . Another few non seedy plants were found by the stake near the cattle yard. Time: 32 hours
Mullein (creticum and great)
Scattered as usual. A few great mullein were removed from the lower section of the Winter Cove erosion gully, two from the high site about halfway to Winter Cove, several where the Garden Cove track meets the airstrip, and several scattered plants behind Garden Cove. A large creticum mullein rosette was found at the eastern end of Garden Cove, several small rosettes at each of the markers near the dam, and some from the site at the inland end of the old track parallel to and east of Garden Cove Creek. Time: 12 hours
Efforts to keep this major weed in check continue until we are able to conduct a concerted attack.
Several small outliers at Garden Cove and on the hillside above Typha Pool were checked and treated where necessary. 100 plus plants were dug at Dallas’s patch at the northern end of Winter Cove, and one from the foreshore below this patch. A similar number were removed from the patch on the steep bank at the mouth of Winter Cove Creek.
A couple of hundred were dug from the airstrip patch after a thorough search found several colonies on the Flag Hill side, and in the gully towards East Cove.
The patch on the beginning of the Winter Cove track was checked, and most plants were very small and hard to get, so it was left for the November bee.
The main patch has advanced southwards, and we spent a day and a half bagging flowering and seedy plants, and digging rosettes on the front south of the Winter Cove track. Rosettes and seedlings growing in the slashed part of the track were dabbed with glyphosate.
Following earlier discussions with Richard Holloway who we are consulting in relation to biological control, a careful check was made of flowering plants throughout the main patch checking for any signs of the presence of ragwort flea beetle – sawdust in leaf axils and bore holes in the stem. None were found.
Several seedlings were dug from marked sites where mature plants had been removed previously from Garden Cove and Little Squally. Several rosettes were found (and removed) scattered through the bush between the western ends of Garden Cove and Winter Cove tracks. Time: 105 hours
Relocation of the Fence and Extension of the Exclosure
Following discussion with Wayne, the exclosure at East Cove was further extended to include part of the hillside from its existing top fence up to the Residence Compound and northwards towards the road. The purpose of this was to promote the growth of a better cover of native vegetation. This in turn should help control run-off of rain water after dry periods and lessen the danger of erosion. All materials were salvaged from fences no longer required. All working bee participants assisted with this project. 320 metres of new fence was constructed. Two lucky wallabies escaped the round up. Time: 256 hours
Revegetation and erosion control
20 seedling sheoaks were dug from Garden Cove road, potted, and left in the garden where they will be protected and watered, ready for planting out in November. Three cuttings of layering saltbush were taken and transplanted to the gully below Telstra Corner, protected with tree guards. Disused tree guards and small cages were collected and stockpiled adjacent to the main wire dump ready for re-use in November. The retaining wall below the end of the barbecue slab was rebuilt and strengthened with rock. Some sheoak logs were collected from Winter Cove track and laid on the sandy banks either side of the jetty-barbecue area. The drain through the salt bush at the lowest point on the road between the stile and the jetty was re-opened. Time: 16 hours
Tools and equipment
Dabbers were cleaned as required. Secateurs and loppers were also thoroughly cleaned at intervals during, and after the bee. Before leaving, all equipment was cleaned, and stored as listed in the Weed Folder. An inventory of herbicides, associated chemicals, weeding equipment and relevant personal protective equipment was prepared. Time: 20 hours
Photo points were monitored as usual. Time: 4 hours
This is the record of the weeds being treated on the island, treatment given, the known weed sites, and the time taken to do the work. The progress made in weed management had made it out of date and less relevant. New maps have been added, new site descriptions, and some alternative treatments. Time: 25 hours
Breakdown of time spent on each task