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Lots of invertebrate news!
Niall Doran(Niall.Doran@dpiwe.tas.gov.au) & Mike Driessen, WHA Fauna, Nature Conservation Branch, DPIWE, GPO Box 44, Hobart TAS 7001

Invertebrate work has been the focus of attention for the Nature Conservation Branch of DPIWE recently, both within the branch and in cooperation with other agencies. The following summary of some of these events includes a gratuitous amount of information about spiders and the World Heritage Area information, for which we make absolutely no apologies!

Searching for tiny spiders. Late last year Hydro Tasmania allowed us to tag along on one of their monitoring trips along the Gordon River. This gave us access to a host of different sites on the river to survey for the presence of Olgania excavata, the little six-eyed spider ('Rare' under the Threatened Species Protection Act 1995) within the World Heritage Area. This species is only 1 mm in body length, and is known from only five widely distributed sites, including Bubs Hill, the Gordon River Valley and Ida Bay. It was first collected in the Gordon River surveys conducted for the HEC in the 1970s, from a (presumed) habitat of moss and wet leaf litter.

Sampling involved the collection of moss and leaf litter samples, which were subsequently run through Berlese-Tullgren funnels. Additional samples were taken near recorded localities at Arthurs Folly and Bradley Chesterman caves near Ida Bay. Extracted material is currently being divided into six groupings (spiders, pseudoscorpions, multipedes, amphipods, snails and 'everything else'). Plenty of little spiders have been found so far, but no Olgania - we're still looking! This material will be available to anyone interested in it for future research, and will ultimately be lodged with either QVM or the TMAG.

Searching for bigger spiders. A serendipitous discussion about survey work on Plesiothele fentoni, the Lake Fenton trapdoor ('Endangered' under the TSPA), led to the discovery of an unexpected range extension for the species. This species had been considered 'Extinct' until being rediscovered by Robert Raven (Queensland Museum) and Maria Moore in 1996. The spider is known from only one restricted location near Mt Field. Surveys we undertook in 2001 to help plan maintenance and management work for the area confirmed the continued existence of this colony, as well as finding specimens in nearby areas where burrow densities were notably high. This work was being discussed by Niall and Bob Mesibov at QVMAG when Lisa Joy Boutin (QVMAG spiders curator) casually commented on having seen a specimen of P. fentoni in a sample she had been sorting two days before. It was even more surprising when Lisa subsequently produced it, the spider having come from miscellaneous pitfall material collected at Tarraleah by Ray Brereton in 1992!

Plesiothele fentoni

This represents a substantial range extension for the species, and a potentially remarkable increase in conservation security for the species (depending on the size and current condition of the Tarraleah population). It also raises the question of where the species may occur between and beyond these sites. We also need to ask what other secrets are hiding away in all that ancient unsorted material that we all have hidden away, whether we like to admit or not!

Searching for the biggest spiders. Hickmania troglodytes, the Tasmanian cave spider, remains one of Niall's favourite animals. He was therefore very pleased when an American documentary crew for the Animal Planet program contacted DPIWE to ask about this species, and whether they would be able to film it when they came to Tasmania. While they were also interested in the vertebrate fauna, this at least showed recognition of growing interest in our invertebrate species. Even better, the program presenter was keen to ensure all of his facts were right throughout filming, and he presented the spider as a 'fascinating, interesting animal' in its own right rather than from the 'creepy-crawly' point-of-view that spiders usually suffer.

Hickmania troglodytes

Effects of fire on invertebrates. This project continues to dominate WHA fauna management research. The third year of post-burn data was collected from highland sites at Lake St Clair in February 2002. Lowland sites at McPartlan Pass were finally burnt in spring last year, but no sooner had we said 'Whew, finally got that done', than an escaped forestry burn (the next day!) ripped across the plains and burnt three of the four control grids and reburnt two grids that were burnt in Autumn 2001. This will obviously present some interesting challenges for analysis.

Collected material is slowly but surely being identified to species or morphospecies level. Robert Raven has worked his way through over 20 000 spiders. Data on the preliminary impacts of fire on spiders were presented at the Invertebrate Biodiversity & Conservation Conference in Adelaide in December, 2001. Other groups that are currently being identified include flies (15 000+ specimens, by Gunther Theischinger), springtails (10 000+ specimens, by Penny Greenslade), millipedes and centipedes (500+ specimens, by Bob Mesibov), snails (1000+ specimens, by Kevin Bonham), mites (Owen Seeman), beetles, moths and butterflies (Peter McQuillan), caddis-flies (Arturs Neboiss and Alice Wells) and bugs (Gerry Cassis).

Anyone with an interest in identifying Hymenoptera, Psocoptera, Opilionida and Thysanoptera should contact us, as we can make your day or (more likely) your year.

Survey for Allanaspides hickmani. Last spring Shaun Thurstans commenced a survey of the distribution of this rare syncarid crustacean. It was previously known from only three locations in the Lake Pedder-McPartlan Pass Area, one of which is now submerged under the new Lake Pedder. Shaun searched areas to the north of the known locations and the gaps between existing sites. It appears that Allanaspides hickmani is confined to flat areas of buttongrass moorlands within the McPartlan Pass area (approximately six square km) and extends west for about 3 km into small patches of buttongrass either side of the Gordon River Road (within about 200 m). Pierre Horwitz found the species at one location on the southern side of Lake Pedder during the 1980s. We aim to do further surveys along the southern side of Lake Pedder and an area on the northern side of Lake Gordon.

WHA invertebrate values. The Tasmanian Wilderness was first listed as a world heritage site in 1982 and was expanded in 1989. Since that time there has been a considerable amount of research in the WHA, and fauna work has focused on invertebrates, with important results. For example, the strange marine invertebrate community of Bathurst Channel was not known when the WHA was last listed. Stephen Mallick and Mike Driessen are now revising and updating the WHA fauna values. We will be seeking advice (and have already done so) from a number of invertebrate specialists. If you have any information on WHA invertebrate values we would love to hear from you. The WHA criteria are (briefly summarised):

        1. Faunal evidence of Pangea and Gondwana
        2. Evidence of on-going biological evolution
        3. Outstanding natural phenomena
        4. Rare and threatened species

As part of the review of values we are also trying to complete an inventory of recorded WHA invertebrate fauna. This is obviously a mammoth task and will take some time complete.

Public education and awareness is ever important, and invertebrate information has recently been updated and provided to field centers at Hastings and Mt Field. Outside the WHA, invertebrate interpretation is being developed for Flinders Island and Freycinet.

Mt Weld/Warra invertebrate altitudinal transects. This is a co-operative project between ourselves, Forestry Tasmania and the University of Tasmania, as previously described in Invertebrata 20 by Dick Bashford. We have been torturing a wide range of unsuspecting volunteers on the slopes of Mt Weld, to help gather a vast amount of invertebrate material from this remote and often inhospitable area. This has involved a massive undertaking of people hours and effort in the field, and thanks are due to the following people without whom it could not have been achieved: Suzette Wood*, Mark Weeding*, Jonah Gouldthorpe*, Colin Shepherd*, Kevin Doran*, Ray Brereton, Alistair Scott, Alastair Richardson, Sally Bryant, Helen Daly, Ursula Taylor, Belinda Yaxley, Shaun Thurstans, Simon Grove, Chris Palmer, and Peter Dalton (Robbie Gaffney and Nicki Meeson about to find out what it's all about). Those people marked with an asterisk, along with Mike, were silly enough to go more than once!

The mammoth job of sorting to ordinal level has been undertaken by the ever-reliable Judi Griggs at the Forestry Tasmania labs, with continued project support from Dick Bashford and Andy Muirhead. With sample collection now drawing to a close, finer scale taxonomic identification and data analysis will now be undertaken between the three organizations in conjunction with specialist advice on the respective groups.

Montane rainforest on Mt Weld

Burrowing crayfish. Outside the WHA program, last year produced some very satisfying results for Engaeus burrowing crayfish. A fourth species was added to the TSPA as 'Vulnerable', this being E. martigener, the Furneaux burrowing crayfish. Engaeus spinicaudatus, the Scottsdale burrowing crayfish, was also upgraded on the TSPA from 'Vulnerable' to 'Endangered.' Most significantly, DPIWE (NCB) nominations of all four of these species under the Environment Protection and Biodiversity Conservation Act 1999 were accepted, and they joined only four other invertebrates listed for protection under the Commonwealth legislation as at the end of last year. The Tasmanian giant freshwater crayfish is among the others.

While listing or upgrading the conservation status of a species is itself not something to be celebrated, it does at least provide recognition of the plight of these animals, and provides a mechanism for conservation work on them. Although single species approaches do not necessarily target biodiversity conservation overall, they do allow for the protection of species under particular threat, and these species can in turn provide an identifiable 'face' or image for conservation messages across the wider community.

Engaeus martigener

The Burrowing Crayfish Group Recovery Plan (2001-2005) produced by DPIWE (NCB) was formally adopted by the Commonwealth government in 2001. Although it did not receive full funding under the NHT, it has received partial funding in a co-operative rehabilitation and community awareness project between the Launceston Environment Centre and DPIWE. Jim Nelson has been busily completing previous community-based crayfish work as well as undertaking key field work for the co-operative project. Jim has been fine-tuning our knowledge of the distribution of the species of greatest conservation concern (E. spinicaudatus), as well as identifying suitable areas for rehabilitation work. He has also been using and modifying a crayfish trap that Phil Bell and Niall used successfully on E. spinicaudatus several years ago, and the three of them hope to write up this trapping technique and data sometime soon.

Coming up!. A lot of different invertebrate work is currently underway within the Nature Conservation Branch, but more is currently on the drawing boards. Niall is hoping to outline a proposal for broadscale invertebrate inventory, assessment and prioritisation in the not too distant future (stay tuned!). With Tasmania due to hold the next Invertebrate Biodiversity and Conservation Conference in 2003, there is no better time for us to showcase the unusual, unique and fascinating invertebrate fauna that we have, the expertise of the various people, groups, institutions and organisations we have working on it, or the threats, pressures and challenges that it faces.

A tale from the tail end
Bob Mesibov (mesibov@southcom.com.au), Research Associate, QVMAG

It's not widely appreciated that most invertebrate species are quite rare.

If you intensively collect almost any invertebrate group, you'll find that a few species are represented in the collection by heaps of specimens, while a much larger number of species are represented by only a few specimens each. Changing the sampling method will change the species proportions a bit, but not usually by much. Most invertebrates are genuinely rare, regardless of how you search for them.

The 'tail-enders' on the abundance list create some interesting problems for invertebrate ecologists. Suppose you want to compare the beetle faunas at similar forest sites A and B, 10 km apart. After, say, 50 hours of collecting at each site, you have an A list and a B list of species. The most abundant species are likely to be present on both lists. However, just under half the species on either list may be there as one or two specimens ('singletons' and 'doubletons'); this is not an uncommon result in such surveys. Down on the tail ends of the lists, there will be big differences between site A and site B.

Are the A and B faunas really the same? If you did more collecting, would those A-only singletons and doubletons turn up in B, and vice versa? Sure, some would, but you'd probably also collect previously unrecorded rarities at B which don't show up at A. And vice versa.

Tail-enders are also a headache for conservation biologists, because that R word 'rare' sounds conservation alarm bells. The problem is that a quick-and-dirty survey of an area is unlikely to turn up tail-enders. You have to search long and hard before you find them, which means that it's extremely difficult to identify areas which may be critical to their survival.

Many Invertebrata readers will have had frustrating and/or colorful experiences with tail-enders. What follows is a recent one of my own.

The area concerned is the Southern Forests block of wet eucalypt centered around Tahune Bridge on the Huon River. For convenience here I'll call it 'the Tahune area.' By any standard, this is one of the best-sampled forest blocks in Tasmania. Over the past 30-odd years, many resident and visiting specialists have driven west from Geeveston to collect their favourite creatures along Arve Road, South Weld Road and Picton Road, and in the Tahune Forest Reserve. There have also been much broader invertebrate samplings, most recently as part of the Warra Long-Term Ecological Research study (see www.warra.com).

Millipede specimens galore have come from these samplings. Some I've looked at were collected in:

        My own, private visits between 1974 and 2001
        Incidental collections by other specialists, notably the late V.V. Hickman
        An Australian Biological Resources Study project in the early 1970s
        University of Tasmania student research projects
        Forestry Tasmania pitfall surveys outside Warra, 1995/96
        Forestry Tasmania pitfall surveys inside Warra, 1997/98

Many more specimens came from logged/unlogged area surveys I did for Forestry Tasmania near Tahune Bridge in 1988 and 1997. The second study alone generated nearly 650 millipede specimens by hand-collecting.

The long-term harvest of millipedes from the Tahune area, about 30 species in all, has the usual abundance pattern. A few species are extremely common, but most are fairly rare. Nevertheless, up to January 2002 I believed I had a pretty good picture of the Tahune area millipede world. If any more rarities were lurking there, I reckoned they were likely to be species which were common elsewhere in the region, such as a dry-forest specialist trying its luck in the Tahune's wet habitats.

I was wrong! In January I checked the 1999, 2000 and 2001 centipede/millipede catches from Warra, which are curated by Dick Bashford at Forestry Tasmania's head office in Hobart (see the recent Invertebrata item by Dick and Simon Grove). There were 468 samples. In each of two of these I found one specimen of a bizarre new millipede species.

At first I placed the new species in a group not previously reported from Australia, on the basis of a resemblance to a millipede from high-elevation rainforest in Madagascar. (Not such a crazy idea, since that rainforest is home to a number of Gondwana alumni shared with Tasmania.) After dissecting one of the two Warra specimens, a mature male, I'm now fairly confident the beast fits within a native family, but it clearly represents a new and very peculiar genus in that family.

Two things make this discovery more than just another addition to the Warra millipede list. The first is that a millipede similar to (but not identical with?) the new species had previously been collected in far southern caves by Stefan Eberhard and Arthur Clarke. The cave specimens were unpigmented, and so different from any surface-dwelling millipedes that I suspected they were relicts from pre-Ice Age times. Now we know that this millipede genus also lives in forest litter, far from any caves, and that in above-ground habitats it's pigmented. The second cause for excitement is the unexpected nature of this creature's appearance. It was found after more than 30 years of hand-collecting and trapping in the Tahune area, lurking among (in all) a couple of thousand pitfall samples.

I'll be looking for more specimens of the new millipede near the relevant Warra pitfall traps this autumn. I know just where those traps are: close to two study sites where I hand-collected millipedes for a total of 25 hours in 1997!

Q. How long does it take to get to know the invertebrate fauna of an area?
A. How much time have you got?!!