Western Banders Association

BIRD RESEARCH IN THE GREAT WESTERN WOODLANDS

Harry F. Recher

Ted Davis (Boston University) and I have been studying birds in the Great Western Woodlands (GWW) since 1997 when we first visited the Yellowdine area east of Southern Cross to study birds in Salmon Gum woodlands (Recher and Davis 2002). Earlier we had worked in Wandoo woodlands at Dryandra (Recher and Davis 1998). In 2000, I initiated a study of birds in York Gum and Salmon Gum woodlands on Mt Gibson Station (Recher and Davis 2010) and in 2003 we commenced work on birds in eucalypt woodlands along the Norseman-Hyden Road 10-45 km west of Norseman. Commencing in 2005 we were able to join an ARC funded project with The Wilderness Society and people from the Australian National University (Recher et al. 2007). We’ve continued this work through 2010 using our original study areas at Yellowdine and Norseman, while adding new sites in woodlands west of Widgiemooltha 10-45 km along Cave Hill Road and north of Norseman in similar woodlands 25-35 km along the Coolgardie-Norseman Road. I’m happy to provide GPS coordinates to anyone wanting to visit these areas, especially as these represent some of the best woodlands remaining in Australia and are under significant threat from a variety of human impacts, including climate change, tourism, mining, and increased fire frequency, so if you want to see them you need to be quick.

 I’ve only mentioned the more conspicuous eucalypts in each region and have ignored the mallees, which is an injustice to the rich flora of the GWW (see Watson et al. 2008). Ted and I began working in the GWW because we wanted to study a eucalypt woodland avifauna that might still be intact. The GWW appeared to fit this demand as a core 7.5m ha of its ~21m ha has never been grazed by domestic stock and there was little evidence of feral goats, camels, or rabbits away from pastoral and agricultural lands. Although the GWW is hardly undisturbed, with more than a century long history of mining and logging (pit props, timber, fuel-wood), including extensive clear-felling, as well as mammal extinctions, I still think it comes closer to having a pristine or original woodland avifauna than anywhere else in Australia. However, this does not mean the avifauna is unchanged. I am now of the view that nomadic and migratory species, particularly nectar-feeders, have been adversely affected by the clearing of the wheatbelt to the west and south of the GWW and by the degradation of pastoral lands throughout the mulga country north and east of the GWW. Although numbers of nomadic and migratory species can at times be quite extraordinary, this does not mean they or any particular species are abundant. Nomads and migrants commonly congregate at particularly rich sources of food, such as flowering eucalypts or outbreaks of psyllid insects (lerp), creating an illusion of abundance, when in fact there are relatively few birds when the GWW as a whole is taken into account. The really abundant birds in the GWW are the residents, mainly sedentary species, such as Weebill, Inland and Chestnut-rumped Thornbill, Redthroat, and Yellow-plumed Honeyeater. These occur throughout the GWW, often in considerable densities.

 We had a primary goal of coming to understand and quantifying the ecology of eucalypt woodland birds, with the aim of using this information to better inform conservation management of eucalypt woodlands throughout Australia. While there has been considerable research on birds in Australia, we really know very little about the details of their lives, the foods they eat, where they feed, how they use or do not use different kinds of plants for foraging and nesting, how abundant they are, how numbers change with time or in response to drought and fire, when and where they nest, and so on. Moreover, some of the most widely accepted facts about even common Australian birds are just plain incorrect, but are perpetuated from one generation to the next because there are really very few people who take the time to study birds in the wild. The approach Ted and I took was to concentrate on avian foraging behaviour (how and where birds foraged and the foods they ate) for all species encountered. Our procedures are described in the references given below. We worked mainly from late winter to late spring as this was a time we could also obtain information on breeding and nesting and because is a time when numbers of birds are relatively stable. We’d be the first to admit that much more needs to be known about our birds during winter and summer; summer in particular. Spring is also an efficient time to work as it is relatively cool and birds are active for long periods during the day. Obtaining foraging data is therefore relatively easy. By including all species and having multiple sites (we have more than 80 plots in the GWW) we can quickly acquire quantitative natural history information for a large number of species.

 Natural history information is the backbone of ecological research from which testable theories and models are derived. It is also the core of good conservation management, but not enough is done these days in Australia with the emphasis on experimentation, experimental design, computer modelling, and statistical analysis. Too much time is spent in the cloisters and not enough in the field. We no longer teach natural history at school or university, with the result that increasingly few Australians have any understanding or regard for their environment or concern for other species. This includes many biologists and people being trained in resource and environmental management.

 I’m probably digressing here, but I think understanding why people do research is as important as understanding how they do it.

 In all of the GWW there are about 215 species of birds, including water and wading birds (Watson et al. 2008), but I consider this an overestimate. Keeping in mind that we only work in eucalypt woodlands and exclude mallee and shrublands from our studies, Ted and I have recorded 86 species of birds on our plots at Yellowdine, Widgiemooltha, and Norseman. Foraging and nesting data have been obtained for most of these.

 Not all species occur in all of those localities and most make quite specific habitat choices. Many, more mature and closed woodlands, especially those with Dundas Blackbutt and Red Morrell, are dominated by Yellow-plumed Honeyeaters, which exclude most smaller birds, such as Weebills, pardalotes and thornbills from their colonies. Thornbills, in particular, are most abundant in the more open woodlands with a well developed and species rich understorey and shrub layer. So long as there is a eucalypt canopy with lerp and no Yellow-plumed Honeyeaters, there will be Weebills and Striated Pardalotes. Gilbert Whistler appear most frequently where there is an abundance of Exocarpos aphyllus and feed heavily on Exocarpos fruit at all stages of ripeness (Davis and Recher 2009). Similarly we only find an abundance of nectar-feeders where eucalypts are in bloom. Eucalypts are almost the only source of nectar on our plots and provide the only really rich flows of nectar. The recent prolonged drought in the GWW has meant reduced numbers of nectar-feeders, both honeyeaters and Purple-crowned Lorikeet, and raises the question of where these birds go when nectar is not available in the GWW. I suspect many used to move west and south into higher rainfall zones where there is a greater variety of nectar-rich plants, but much of this land has been cleared for farming. It is likely that the numbers of nectar-feeders in the GWW were reduced many years ago, as the wheatbelt was cleared; the abundance of a species will always be determined by the least abundant resource. In the instance of nectar-feeders in the GWW, that would be nectar during times of drought.

 The drought in the GWW has also affected other birds, with ground-foraging species, such as Chestnut-rumped Thornbill, Dusky Woodswallow, and Rufous Treecreeper, showing signs of decline since 2003/2005. Others, such as Inland Thornbill, have shifted their foraging habits and now feed higher in the canopy. Presumably eucalypts are better able to maintain productivity during drought and will therefore sustain invertebrates as food for birds longer, but that is really a hypothesis, not an answer. In 2008, food chasers, such as trillers failed to appear, and now some of the canopy foraging insect-eaters, such as Black-faced Cuckoo Shrike are present only in greatly reduced numbers. The absence of big flocks of nectar-feeders also led to the decline of birds of prey, such as Little Falcon and Brown Goshawk.

 Drought, of course, leads to fire and in 2006 we set up a study to monitor the recolonization of woodlands burnt in a wildfire north of Norseman in December 2005. Our aim was not just to record what species and when birds return to the burnt area, but how each species uses the new vegetation for foraging and nesting. I’ve conducted extensive post-fire studies on birds in eastern Australia and have never encountered anything so different as the post-fire environment on those Norseman plots. Recovery is slow, with many trees killed and regrowth occurring from seeds and lignotubers, with almost no epicormic growth. Five years post-fire and the birds using the burnt area are a tiny subset of the original avifauna, as judged by the birds in adjacent unburnt forest. It will be decades or longer before a complete woodland avifauna is recovered highlighting the long-term consequences of more fires from more frequent drought with climate change and from simply having more people, more tourists, more miners, more bird-watchers using the GWW.

 This is probably enough for you to have an idea of what Ted and I have been doing in the GWW. Details can be found in the papers we've published and you can also find an overview of the application of our studies in Recher et al. (2010). The bulk of our work is now being prepared for a book, as I am fed up with the long delays, especially from referees, encountered with publishing in most scientific journals and the need to assign copyright to multinational publishing houses. You can also probably guess my disdain of referees who seem to think natural history studies do not merit publication unless accompanied by tedious and unnecessary statistical analyses. Ted and I have either paid for our research ourselves or it has been paid for by you and other tax payers and should not be used for profit by big (or small) corporations. If our original goals and aims in this research are to be achieved, then our work must not only be published, but it must be free and freely available to everyone needing or wanting to use it.

 Harry F. Recher

Edith Cowan University

School of Natural Sciences, Joondalup, WA 6027

 email: hjrecher@bigpond.com