Andrew W. Claridge

Diversity and habitat relationships of hypogeous fungi. II. Factors influencing the occurrence and number of taxa

Fruit-bodies of hypogeous fungi were sampled over two seasons across 136 forested study sites representing a stratified sample of the climatic, geological and topographic features of far south-eastern mainland Australia. Two hundred and nine species, over three-quarters being undescribed, were recorded. Statistical models based on various environmental attributes measured for each site were developed for the occurrence of several common taxa. At a landscape scale, climatic factors such as mean minimum temperature of the coldest month and annual mean moisture index were important explanatory variables for most taxa examined, but the type of response varied. More locally, topographic position, soil fertility, time since last fire and micro-habitat structures such as the leaf litter layer and number of large fallen trees also influenced the distribution of taxa in different ways. A model was then developed for the number of fungal species occurring at each site. Important explanatory variables were type of substrate, topography and diversity of potential host eucalypt species. The utility of each model constructed needs evaluation by further sampling of hypogeous fungi. Possible implications of our findings for forest management are discussed. Further analyses of our existing data are also identified.

Use of infrared digital cameras to investigate the behaviour of cryptic species

In this paper we report on the application of infrared digital cameras to investigate aspects of the breeding biology of the spotted-tailed quoll, an endangered marsupial carnivore. Technical details are provided about the cameras, which were deployed remotely at two ‘latrine’ sites used by the target species within Kosciuszko National Park in southern New South Wales, Australia. Examples of images captured by the cameras are presented, with notes on possible application of the same technology to better understand the social behaviour of rare and cryptic species.

Recommended guiding principles for reporting on camera trapping research

Camera traps are used by scientists and natural resource managers to acquire ecological data, and the rapidly increasing camera trapping literature highlights how popular this technique has become. Nevertheless, the methodological information reported in camera trap publications can vary widely, making replication of the study difficult. Here we propose a series of guiding principles for reporting methods and results obtained using camera traps. Attributes of camera trapping we cover include: (i) specifying the model(s) of camera traps(s) used, (ii) mode of deployment, (iii) camera settings, and (iv) study design. In addition to suggestions regarding best practice data coding and analysis, we present minimum principles for standardizing information that we believe should be reported in all peer-reviewed papers. Standardised reporting enables more robust comparisons among studies, facilitates national and global reviews, enables greater ease of study replication, and leads to improved wildlife research and management outcomes.

Diversity and habitat relationships of hypogeous fungi. I. Study design, sampling techniques and general survey results

Hypogeous fungi are a large yet unknown component of biodiversity in forests of south-eastern mainland Australia. To better define their diversity and habitat relationships, we identified and counted fruit-bodies at 136 study sites sampling the climatic, geological and topographic features of the region. In one year 7451 fruit-bodies representing 209 species were collected in an autumn and spring sampling period. Only 57 of these species were previously described. Within genera, the number of species ranged from 1 to 21. Sites sampled in autumn averaged higher diversity of species and greater number of fruit-bodies than the same sites sampled in spring. Most major taxa occurred at more sites in autumn than in spring, whereas a few occurred more frequently in spring than in autumn. These patterns are consistent with those identified in previous smaller studies and likely reflect seasonal changes in soil moisture and temperature levels. Subsequent papers will explore factors influencing the occurrence, relative abundance and numbers of species of hypogeous fungi at the study sites and their community structure and possible host–plant relationships.

Mycophagy by small mammals in the coniferous forests of North America: nutritional value of sporocarps of Rhizopogon vinicolor, a common hypogeous fungus

Abstract We evaluated the nutritional value of sporocarps of Rhizopogon vinicolor, a common hypogeous fungus in the coniferous forests of North America, for two small mammal species: the Californian red-backed vole (Clethrionomys californicus) and the northern flying squirrel (Glaucomys sabrinus). Although the nitrogen concentration of sporocarps was high, much of it was in non-protein form or associated with cell walls, suggesting that it may be of low nutritional value or protected from mammalian digestive enzymes. Sporocarps also had high concentrations of cell wall constituents, indicating low availability of digestible energy. When fed a diet of this fungus alone in a controlled feeding experiment both mammal species lost a small amount of body mass. Digestibilities of dry matter, nitrogen, cell wall constituents and energy from sporocarps by both species were lower than the digestibilities of other food types by other similarly sized small mammals. Red-backed voles digested the various components of sporocarps at least as well as the flying squirrels, even though they were almost six-fold smaller in body mass. This observation supports the notion that red-backed voles, like other microtine rodents, have morphological and physiological adaptations of the digestive system that are postulated to permit greater digestion of fibrous diets than predicted on the basis of body size. Despite this, our results re-affirm previous conclusions that hypogeous fungi are only of moderate nutritional value for most small, hindgut-fermenting mammals. Future studies should focus on the importance of mixed-species of fungi in the diet of small mammalian mycophagists.

Mycorrhizal effectiveness of Rhizopogon spores recovered from faecal pellets of small forest-dwelling mammals

Mature basidiomes of the hypogeous ectomycorrhizal fungi Rhizopogon vinicolor and R. truncatus were fed to three species of mycophagous mammals in captivity. Spores which passed through the digestive tract of the mammals were isolated from faecal pellets. The metabolic activity and mycorrhizal effectiveness of these spores was assessed. Flouricene-diacetate (a vital stain) was used to assess spore metabolic activity. Mycorrhizal effectiveness was determined by inoculating Douglas-fir (Pseudotsuga menziesii) and ponderosa pine (Pinus ponderosa) seedlings with spore slurries. The same assays were performed on spores isolated from uneaten basidiomes. Spores from R. vinicolor were viable after passage through the gut of each mammal species but the digestive process did not substantially enhance or detract from the ability of spores to form ectomycorrhizas relative to spores from uneaten basidiomes. Spores recovered from faeces of Californian red-backed vole (Clethrionomys californicus) and Townsends chipmunk (Tamias townsendii) had significantly higher metabolic activity than spores from uneaten basidiomes and those recovered from northern flying squirrel (Glaucomys sabrinus) faeces. Spores from eaten and uneaten basidiomes of R. truncatus failed to show any signs of metabolic activity and largely failed to form ectomycorrhizas on seedlings. The reasons for this are unclear but we suggest that germination of spores from this fungus may depend upon other factors. Our findings add to the growing body of literature demonstrating that spores of at least some species of hypogeous fungi remain viable after passage through the digestive tract of mycophagous animals.

Desert Truffles of the African Kalahari: Ecology, Ethnomycology, and Taxonomy

Desert Truffles of the African Kalahari: Ecology, Ethnomycology, and Taxonomy. The Khoisan people of the Kalahari Desert have used truffles for centuries. The extreme conditions in which desert truffles grow means that they fruit only sporadically when adequate and properly distributed rainfall occurs, and then only where suitable soil and mycorrhizal hosts occur. Truffles are hunted in the Kalahari by men and women; they look for cracks in the soil, often humped, caused by expansion of the truffles, which are then extracted with hands or digging sticks. The truffles are eaten raw or cooked (boiled, roasted over fire, or buried in hot ashes). Commercial harvest of Kalahari truffles has increased in the last decade and the quantities harvested have been observed to be declining where livestock have been concentrated.

Desert Truffles of the Australian Outback: Ecology, Ethnomycology, and Taxonomy

Desert Truffles of the Australian Outback: Ecology, Ethnomycology, and Taxonomy. The Aborigines of central Australia have traditionally used desert truffles as food. Truffle hunting in the desert requires substantial ecological knowledge, as truffles occur sporadically and only with adequate and properly distributed rainfall as well as the presence of necessary soil conditions and mycorrhizal hosts. Truffles are hunted primarily by women, who look for cracks or humps in the soil caused by expansion of the truffles, which are then extracted with digging sticks. The truffles are typically eaten raw or baked or roasted in ashes. Seven truffle species are recorded from the Australian Outback, including three that have been only recently described.

There’s no accounting for taste: bait attractants and infrared digital cameras for detecting small to medium ground-dwelling mammals

Context Reliable information about the occurrence and distribution of threatened forest-dwelling mammals is critical for developing effective conservation plans. To optimise limited resources, advances need to be made to the toolkit available for detecting rare and cryptic fauna. Aims We trialled three bait attractants (peanut butter with oats, live mealworms and black truffle oil) in combination with infrared digital cameras to determine whether detection rates of forest-dwelling native mammals in south-eastern Australia were influenced by: (1) bait type; (2) previous visits by conspecifics; (3) previous visits by Rattus; and (4) duration of bait deployment. Methods Bait attractants were set at 40 camera stations in combination with odourless controls. Over two fortnight-long deployments, 1327 images were captured of 22 mammal and bird species. From these data, detailed statistical analyses were conducted of six mammal genera. Key results Peanut butter with oats was found to be a significantly better attractant than empty bait holders for Antechinus, Isoodon, Perameles and Rattus, but not for Potorous or Pseudocheirus. Truffle oil and mealworms were also significantly better attractants than the control for Rattus but not the other five genera. When Antechinus, Isoodon, Potorous or Rattus were detected at a bait station there was a significant likelihood they had been detected there during the previous 24 h. This was not the case for Perameles or Pseudocheirus. A prior visit by Rattus to a station had no significant influence on the detection probabilities of Antechinus, Isoodon, Perameles, Potorous and Pseudocheirus during the subsequent 24 h. Detection probabilities for Isoodon and Rattus declined significantly during the fortnight-long deployments but trends for the other genera were not significant. Conclusions Peanut butter with oats is an excellent general purpose bait for detecting small to medium-sized mammals. However, scope exists for using other baits to target species. For example, truffle oil baits may reduce by-catch of non-target Rattus in labour intensive cage trapping of bandicoots. Regardless of bait type, longer deployments are necessary to detect Perameles, Potorous or Pseudocheirus than Antechinus, Isoodon or Rattus. Implications Targeted detection of predominantly ground-dwelling mammals may be improved by better understanding the attraction of species to baits and required bait deployment times.

Efficacy of hair-sampling techniques for the detection of medium-sized terrestrial mammals. I. A comparison between hair-funnels, hair-tubes and indirect signs

We compared the efficacy of two different designs of hair-tube for detecting medium-sized, terrestrial marsupials in a range of forest types in south-east New South Wales. The two designs compared were a large-diameter PVC pipe (large hair-tube) and a tapered hair-funnel. In addition, the relative abundance of forage-diggings of the same marsupials was estimated simultaneously in order to provide an independent assessment of their distribution within the same study area. Only two hair-tubes out of 620 contained hair that could be attributed to the target fauna, both from the long-nosed bandicoot (Perameles nasuta). This was despite the widespread occurrence of forage-diggings at all of the 31 transects that were surveyed. Only two species of mammal, the agile antechinus (Antechinus agilis) and the bush rat (Rattus fuscipes), were detected in sufficient quantity to enable statistical analysis comparing the efficacy of the two hair-tube types. For R. fuscipes the large hair-tube was significantly more effective than the hair-funnel. Conversely, the hair-funnel was significantly more effective in detecting A. agilis than the large hair-tube. Our results suggest that both designs of hair-tube, in their current form, are ineffective for surveying for medium-sized terrestrial marsupials. We see three important issues regarding hair-tube design and implementation that require more attention before this technique can be considered an effective surveying tool: hair-tube morphology, the material used to capture hair, and bait type.