Ray Thomas
Key words: Agricultural landscape, faunal recovery, community participation, seed production area
Twenty-one years of plantings in the Lurg Hills, Victoria, have seen a consolidation of the work described in the 2009 EMR feature Regent Honeyeater Habitat Restoration Project. The priorities of the Project are to protect and restore remnants and enlarge them by add-on plantings. Together, this work has protected relatively healthy remnants by fencing; restored depleted remnants by planting or direct seeding; and revegetated open areas that had been cleared for agriculture. Other restoration activities include mistletoe removal, environmental weeding, environmental thinning; feral animal control, kangaroo reduction, nest box placement, and systematic monitoring of a range of threatened and declining woodland birds and hollow-dependent mammals.
Updated outputs since 2009. A further 540 ha of private land has now been planted (150 additional sites since 2009). This means the total area treated is now 1600ha on over 550 sites. The oldest plantings are now 19 years old and 10m high (compare to 12 years old and 6m high in 2009) (Fig 1).
The total number of seedlings planted is now approx. 620,000 seedlings compared with 385,000 in 2009. Some 280km fencing has been established compared with 190 km in 2009. Mistletoe now treated on scores of heavily infested sites
Fig. 1. Ecosystem attributes developing in 19-year-old planting at Dogleg Lane (Foster’s). Note pasture grass weeds are gone, replaced by leaf litter, logs, understorey seedling recruitment, open soil areas.
Improvements in genetics and climate readiness. As reported in 2009, seed collection is carried out with regard for maximising the genetic spread of each species, to prevent inbreeding and more positively allow for evolution of the progeny as climate changes. This has meant collecting seed in neighbouring areas on similar geological terrain but deliberately widening the genetic base of our revegetation work. We are also attempting to create as broad bio-links as possible so that they are functional habitat in their own right (not just transit passages). This may allow wildlife to shift to moister areas as the country dries out. With a species richness of 35–40 plant species for each planting site, we also enable natural selection to shift the plant species dominance up or down slope as future soil moisture dictates.
2016 Update: In recent years we have engaged with geneticists from CSIRO Plant Division in Canberra, to improve the genetic health of our plantings. Many of our local plants that we assumed to be genetically healthy, have not recruited in our planting sites. For example, Common Everlasting (Chrysocephalum apiculatum) produces very little if any fertile seed each year because it is sterile to itself or its own progeny (Fig 2 video). In fragmented agricultural landscapes, it seems that many of our remnant plants have already become inbred, and it is seriously affecting fertility, form and vigor. The inbreeding level has affected fertility in this particular case, but we have several other cases where form and vigor are seriously affected as well.
Fig 2. Andie Guerin explaining the importance of collecting seed from larger populations. (Video)
Seed production area. We have now set up a seed production area (seed orchard) for about 30 local species that are ‘in trouble’, to ensure that the plants have sufficient genetic diversity to reproduce effectively and potentially adapt, should they need to as a result of a shifting climate. This will allow these populations to become self-sustaining. Each species is represented in the seed production area by propagules collected from typically10-15 different sites (up to 20kms and sometimes 50kms distant) and as many parents as we can find in each population.
We aim for at least 400 seedlings of each species, to ensure the genetic base is broad enough to have the potential for evolution in situ. The planting ratios are biased towards more from the bigger populations (that should have the best diversity), but deliberately include all the smaller populations to capture any unique genes they may have. We plant each population in separate parallel rows in the seed orchard to maximise the cross pollination and production of genetically diverse seed for future planting projects. We have noticed that the health of some of these varieties is greatly improving as a result of increasing the genetic diversity. On one site we direct-sowed Hoary Sunray, sourced from a large population, and it has since spread down the site very quickly (Fig 3).
Fig 3. Small sub-shrubs and herbaceous species are generally not planted in stage 1 of a project, as the weed levels are often too high for such small plants to succeed. These plants are only introduced in stage 2, when the weeds have diminished up to a decade later. This approach has been very successful with direct seeding and planting some of our rarer forbs.
Recruitment of Eucalypts now evident. Nearly 20 years on from the first plantings, we can report that quite a number of sites have eucalypts old enough to be flowering and seeding, and some of them are now recruiting. We are delighted that our early efforts to broaden the planting genetics are demonstrating success with such natural processes (Figs 1 and 3). Ironbark recruitment from our plantings commenced in 2014 and Red Box commenced in 2015.
Recruitment can also be seriously affected by herbivore problems, particularly rabbits. In recent years we have been undertaking careful assessments of rabbit load on a potential planting site and have gained some advantage by deploying an excavator with a ripper attached to the excavator arm. The excavator allows us to rip a warren right next to a tree trunk (in a radial direction), or work close to fence without damaging either. We’re finding this is providing a very good result. On one site we suspected there were a few warrens but it turned out to be just short of 30 warrens within 100 m of the site – each with 30-40 rabbit holes. After ripping all of those, we ended up with activity in only 2 of the warrens, which were then easily retreated.
We have had such good results with the rabbits on some sites that we are trialing planting without tree guards – it’s much more efficient on time, labour, and costs. And adjacent to bush areas, where kangaroos and wallabies are a significant threat to plantings, this process has an extra advantage. It seems that macropods learn that there is something tasty in the guards, so a guard actually attracts their attention. Our initial trials are producing some good results and given us confidence to expand our efforts with thorough rabbit control.
Faunal updates. An important objective of the project is to reinstate habitat on the more fertile soils favoured for agriculture, to create richer food resources for nectarivorous and hollow-dependent fauna including the Regent Honeyeater (Anthochaera phrygia). In 2009 the Regent Honeyeater was nationally Endangered and was thought to be reduced to around 1500 individuals. By 2015, it was thought to be reduced to 500 individuals, and so has been reclassified as Critically Endangered.
Regent Honeyeaters have turned up in recent years in gully areas where the soils are deeper, the moisture and nectar production is better, and there is a bit more density to provide cover against the effects of aggressive honeyeaters like the Noisy Miner (Manorina melanocephala). The Regent Honeyeaters have been able to remain on such sites for around for a week or more, but have not bred on the sites to date. But breeding has occurred about 15kms away on the eastern edge of our project area. Radio-tracking showed that these breeding birds were some of the captive-bred birds released at Chiltern 100km further NE, and that the birds came towards Lurg after the Chiltern Ironbarks had finished flowering. We consider it to be just a matter of time before the Regent Honeyeaters will find the many habitat sites we’ve planted on higher productivity soils in the Lurg area.
Formal monitoring of Grey-crowned Babbler (Pomatostomus temporalis temporalis) for the past last 13 years has documented a rapid rise (due to some wetter years) from 60 birds in 19 family groups to approx. 220 birds in 21 family groups. There is also exciting evidence that the endangered Brush-tailed Phascogale (Phascogale tapoatafa) is returning to the Lurg district. The distinctive shredded Stringybark nests are now found in scores of our next boxes (up to 10km from the site of our first records of 2 dead specimens in the south of our project area in the mid 1990s). This dramatic population spread is presumably a direct result of our carefully located corridor plantings that have bridged the habitat gaps all across the district.
Increased social engagement. In the last 6 years we have increased the number of visits to planting days by 50 per cent. There has been a steady growth in the number of new local landholders involved and the total number is now 160 landholders engaged, compared with 115 in 2009. Everyone we come across knows of the project and anyone new to the area hears about it from one of their neighbours. Very few people (you could count them on one hand), say they would rather not be involved. In fact we increasingly get cold calls from new people who have observed what has happened on their neighbour’s place and then phone us to say they want to be involved. It’s a positive indication that the project is part of the spirit of the area. This was further confirmed by the inclusion, of a very detailed Squirrel Glider (Petaurus norfolcensis) mural in a recent street art painting exhibition. The permanent artwork is the size of a house wall, and situated prominently in the heart of the parklands of Benalla.
Much of our work has relied heavily on volunteers, with a total of 10,344 students and 24,121 community volunteers involved over the past 21 years. City folk have fewer opportunities to be in nature, with the bushwalking clubs, university students and scouts in particular, really keen to come and roll up their sleeves.
Typically about 17 to 20 of the local schools, primary and secondary, help us with propagating the seedlings at the start of each year and then planting their own seedlings back out into the field in the winter and spring. And we are increasingly getting interest from metropolitan schools that come to the country for a week-long camp. Some of the schools even have their own permanent camps up here and they want to be involved with our hands on work too. “It’s simply part of our environmental responsibility”, is the way they express it.
Contact: Ray Thomas, Coordinator of the Regent Honeyeater Project Inc (PO Box 124, Benalla, Vic. 3672, Australia; Tel: +61 3 5761 1515. Email: ray@regenthoneater.org.au
READ MORE
- Global Restoration Network Top 25 Report: http://regenthoneyeater.org.au/grn.php
- Landcare: http://www.landcareonline.com.au/?page_id=8350
- EMR full feature article: Regent Honeyeater Habitat Restoration Project, Lurg Hills, Victoria
EMR Project Summaries 