Reinfestation of Eucalyptus marginata ground coppice by jarrah leafminer after scorch by autumn or spring fires

Population densities of jarrah leafminer Perthida glyphopa in adjoining areas of jarrah Eucalyptus marginata forest in southwest Western Australia were monitored before and after autumn and spring fires, then compared to examine the effect of fire season and intensity. Densities of leafminer were reduced in tree canopies and on ground coppice after autumn fire scorched the host canopies. Densities of larval mines on ground coppice increased by the second spring after an autumn fire. Numbers of mines on leaves returned to levels indistinguishable from pre-fire values by the second autumn after fire. Leafminer populations on ground coppice appeared unaffected by a spring fire. Mechanisms that may account for observed differences between the effects of spring and autumn fires are discussed. Managed fires are not considered a practical tool for control of leafminer populations.     

Response of bird populations in jarrah and yarri forest in Western Australia following removal of half the canopy of the jarrah forest

Counts of birds present in jarrah (Eucalyptus marginata) forest on ridges and in yarri (E. patens) forest along streams were made during spring in three consecutive years, 1981–83. Thirty-eight species were recorded in set transects during the study. Six species were restricted to yarri, nine occurred only in jarrah, and eleven tended to be more abundant in yarri. The number of birds of all species was greater in the yarri forest.

Early in 1983, part of the jarrah forest was thinned, reducing canopy cover by about one-half, including removal of all Banksia grandis. The bird community showed few immediate changes. Two species were recorded as significantly more frequent after treatment and no species was recorded as significantly less frequent after treatment. The number of bird species present was similar in unlogged and logged jarrah forest. Two species became significantly more abundant in the yarri forest after the jarrah forest was logged. These findings suggest that most bird species in the jarrah forest may be adaptable to gross disturbance of the forest.     

The influence of the jarrah leafminer Perthida glyphopa Common (Lepidoptera: Incurvariidae) and prescribed burning on the girth increment of jarrah Eucalyptus marginata Donn ex Smith

Girth increment in jarrah trees, E. marginata, both resistant and susceptible to the jarrah leafminer, P. glyphopa, was measured at 3 sites between 1971 and 1986 and at another site between 1971 and 1981. Significant annual losses of girth increment were detected in the susceptible trees damaged by the leafminer before and during the time of observation. In trees observed through the development of heavy infestation, significant girth increment losses occurred some 5 years after the damage began. Over the period of observation the mean losses of girth increment in the susceptible trees ranged from 44 to 70%.

Rainfall in both current and preceding years had a significant effect on the girth increment in all trees, but varied between sites. At the drier sites both resistant and susceptible trees responded significantly only to the current year's rainfall, while those at the wetter sites were significantly influenced by rainfall of the previous year. In the susceptible trees this effect was overridden by the influence of damage by the leafminer. Girth increment in both resistant and susceptible trees increased for 1 year after 4 out of 5 ground fires in spring that occurred during the time of observation.     

Forestcheck: the response of vascular flora to silviculture in jarrah (Eucalyptus marginata) forest

Forest understorey vascular plants were monitored across a sequence of time since treatment to assess the effects of silviculture (timber harvesting and regeneration systems) in jarrah (Eucalyptus marginata) forest in south-west Western Australia. Species richness, abundance and structure were assessed at 48 sites in four jarrah forest ecosystems. Monitoring grids in reference forest, which was either uncut or had not been harvested for at least 40 y, were compared to grids in forest that had undergone shelterwood/selective cut and gap release silvicultural treatments. A total of 446 plant species was recorded of which 68, 22 and 35 species were recorded on only one grid within the reference, shelterwood/selective cut and gap release treatments respectively. Silvicultural treatments had no significant long-term effect on mean species richness and abundance of understorey plants, but had a distinct influence on plant community composition. Reference forest had more species of small and medium shrubs compared with silvicultural treatments. Xanthorrhoea preisii (a grass tree) was significantly less common in silvicultural treatments compared with reference forest and Allocasuarina fraseriana (a small to medium tree) and Kennedia coccinea (a vine) were more common on harvested grids. The mean number of plant species per grid was not significantly different between treatments or forest ecosystems. There was, however, strong regional variation in plant community composition, especially in the Jarrah Blackwood Plateau and Jarrah South forest ecosystems and which probably reflects the influence of climatic and edaphic factors on jarrah forest species composition. Dominance-diversity curves for each treatment showed that ranking of species with high abundance was similar in all treatments, but varied between treatments for species with very low abundances. There was no significant relationship between species richness and time since last fire because field assessments were carried out at least 3–13 y after disturbance, by which time species assemblages had stabilised.     

Factors influencing the performance of jarrah leafminer (Lepidoptera) within stands of jarrah forest of Western Australia

The survival rate among larvae of jarrah leafminer Perthida glyphopa in crowns of pole-sized jarrah Eucalyptus marginata at 14 m above ground level significantly exceeds that on leaves in foliage of ground coppice (< 2 m above ground), although the oviposition rate is similar in both cases. This is associated with greater concentrations of leaf N and P, lower concentrations of Ca, Mg and leaf phenols, and lower temperatures within pole crowns. Rate of parasitization of larvae in mines in leaves of pole-sized trees is similar to that in leaves of ground coppice. Poles with foliage inherently resistant to feeding by jarrah leafminer larvae have similar numbers of mines per leaf to susceptible poles, but the larvae in mines of resistant jarrah experience higher mortality than those on susceptible jarrah, and die sooner so that mean area of mines is only about one-third of that on susceptible jarrah. The area of mines is also directly dependent on the mean maximum temperature but not on the mean minimimum temperature. Resistance is associated with lower concentrations of leaf N in young leaves but not with higher concentrations of leaf phenols or lower concentrations of other major nutrients. Explicit criteria for discriminating resistant jarrah are provided; as a result, resistant jarrah can be retained, and susceptible jarrah selectively removed, during timber harvesting operations.     

Forestcheck: the response of birds to silviculture in jarrah (Eucalyptus marginata) forest

In the five-year period from 2001 to 2006, 48 monitoring grids comprising the FORESTCHECK initiative were established in open eucalypt (jarrah, Eucalyptus marginata) forest in south-west Western Australia. Since 1985, revised silvicultural objectives have necessitated detailed monitoring of responses by bird species and assemblages to silvicultural treatments (timber harvesting and associated burning). Few marked changes in the avifauna were detected. Species accumulated (in terms of numbers of grids) at similar rates in gap release, shelterwood/selective cut, and reference (either never harvested or harvested more than 40 years previously) forests. In terms of individuals, species accumulated faster in the gap release forests. The number of species represented as singletons was greatest on the never harvested (8), coupe buffer (7) and gap release (6) grids. Dominance-diversity curves also showed only minor differences between silvicultural treatments. Neither nMDS nor CAP ordinations showed any clear separation between the treatments. There was little evidence of any substantial effect of silvicultural treatments on avian community structure or on individual bird species. Community structure was, however, significantly associated with forest ecosystem/year of sampling. The basal area of live trees was not correlated with bird species richness or abundance on each grid. These results are consistent with previous studies, which indicate that most bird species in jarrah forest have a high threshold level of tolerance to disturbance. It is likely that the rapid regeneration of dominant tree species after harvesting and associated fire, the patchiness of treatments at the landscape scale, the high degree of connectivity of harvested and burnt forests with forests not recently harvested or burnt, and the retention of habitat trees in the most heavily—harvested (gap release) forests all conduce to dampen local-scale impacts and conserve the avifauna in relation to the home range and normal movements of its constituent bird species.     

Effect of Prescribed Burning in a Forest on Wood Characteristics of Jarrah

Wood specimens have been examined which were collected from three positions along the merchantable bole of jarrah (Eucalyptus marginata Sm.) trees growing in Western Australia. These trees had been subjected to a series of two experimental fires at either of two intensities in either spring or autumn. The more intense fire caused crown and trunk damage and resulted in kino vein formation. If such burning took place in autumn, loss of radial growth resulted. The less intense fire treatment did not result in external damage. Minor disturbances to the density profiles in the first year after the fire were the only observed effects on characteristics of the wood.     

A soil heating index for interpreting ecological impacts of jarrah forest fires

Soil heating during forest fires gives rise to numerous ecological responses, many of which are poorly understood. To interpret, predict and manage these responses, such as fire-induced legume regeneration, it is necessary to identify the key fire, fuel and soil factors that affect heat transfer to the soil, and to determine functional relationships incorporating these factors. Heat transfer to the soil was investigated in the laboratory using jarrah forest litter as the heat source to develop a soil heating index for jarrah forest fires. Maximum soil temperature and heat load (the area beneath the temperature history trace) depended on the quantity of surface litter fuel consumed and soil and fuel moisture content, but was independent of fire rate of spread. A linear relationship incorporating these factors was developed to predict the maximum soil temperature at a depth of 10 mm, thus deriving the soil heating index. This relationship, together with knowledge of the temperatures necessary to achieve optimum germination of soil stored seed, can be used to interpret regeneration responses and to prescribe fires to optimise the regeneration of desired species.     

Extreme wildfire behaviour in 3-year-old fuels in a Western Australian mixed Eucalyptus forest

This paper describes the behaviour of an intense wildfire which burnt through three-year-old fuels in open forest of jarrah (Eucalyptus marginata), marri (E. calophylla) and karri (E. diversicolor) near Manjimup, W.A. The fire occurred during very dry fuel conditions which resulted from record high air temperatures (maximum 43.5°C) following a rainless period of twenty eight days. Fire danger at the time was Extreme, with a peak McArthur Forest Fire Danger Index of 65. The fire crowned extensively in mixed-aged jarrah/marri stands, and it is proposed that crown fire initiation was facilitated by the substantial component of sapling and pole-sized regrowth which provided a vertically continuous fuel structure. Concentrated spotting occurred up to 2km downwind of the fire, and an isolated spot fire developed 8km away. During an initial run under north-westerly winds the fire travelled 2.2km with an average forward rate of spread of 1300m/h, which is somewhat faster than predicted by either the Western Australian Forest Fire Behaviour Tables or the McArthur Forest Fire Danger Meter. The relatively low fuel loads in the area appear to have assisted in the rapid containment of the fire once burning conditions moderated.     

A refined method for estimating capsule crops in individual jarrah (Eucalyptus marginata) crowns

An accurate measure of the number of capsules in the crowns of jarrah (Eucalyptus marginata) trees is needed to assess the potential for seedling regeneration prior to silvicultural treatment in jarrah forests. The current method of estimating capsule crops on jarrah trees uses stem diameter and estimates of capsule density in the crown, but has not been fully validated. In this study, we sought to develop an accurate and practical method of assessing capsule crops in the crowns of individual jarrah trees. We did this by measuring a number of tree characteristics prior to felling them. A total of 24 trees were selected, spanning a range of sizes and crown conditions, and the total number of capsules was counted for each tree. Multiple linear regression was used to model capsule number against various combinations of eight different tree/crown variables, with model fit compared using an adjusted coefficient of determination (adjR²). The final model recommended for field use included three easily measured variables (stem diameter, subjective assessment of capsule density, and subjective assessment of capsule clump distribution in the crown) and had a high degree of predictability (adjR² = 0.83), which was the same as that of the full model. This method substantially improved estimates of crown capsule numbers compared with the method currently used (adjR² increased from 0.29 to 0.83), which tended to underestimate canopy capsule numbers.     

Coleoptera in litter of dry sclerophyll eucalypt forest and the effects of low-intensity prescribed fire on their activity and composition in west-central Victoria

Surface-active Coleoptera (beetles) were monitored in dry sclerophyll mixed eucalypt forest of west-central Victoria near Daylesford, and the effects of a one-off low-intensity prescribed fire applied during spring (15 October 1985) or autumn (25 March 1987) were assessed on families and species between 19 March 1985 and 28 February 1989. The study was based on 27 550 adult specimens, ranging in length from 0.5 mm to 22.0 mm and representing 30 families and 109 species, of which 78 species (71.6%) are undescribed. The most commonly trapped ‘major’ families were the Staphylinidae (predominantly predators), followed by the Nitidulidae and Leiodidae (both decomposers/fungus feeders). The specimens were contained in 3 140 pitfall trap samples taken from two sites burnt in spring, two sites burnt in autumn and one ‘control’ site, all adjacent to each other within an 80.5 ha study area. This is the first Australian study that has examined in detail the effects of prescribed fire on both families and species of the Coleoptera within litter of native forest.

A high level of stability in activity was evident among coleopteran populations over the 4-year study period when fire was absent. The same was observed at the two sites burnt in autumn (fire intensity = 176 kW m^?1). Both fires had no effect on family or species richness. However, the spring fire (256 kW m^?1) at one study site temporarily boosted activity of the ‘major’ family Staphylinidae after early autumn of the second post-fire year, and induced a short burst in activity of species Thalycrodes pulchrum (Nitidulidae) during the first post-fire winter, and among Leiodidae during the first postfire spring. At both spring-burnt sites, the pool of the 19 less commonly trapped ‘minor’ families incurred an immediate post-fire upsurge lasting until early summer 1986. As these positive responses at the spring-burnt sites were associated with a 4.41 ha^?1 lower fine fuel load (humus, litter, twigs of < 6mm diameter) during the first post-fire year compared with the autumn-burnt sites, it is possible that they reflect enhanced trapping efficiency and not increased population levels. Until this question is resolved, it appears preferable to apply any necessary one-off prescribed fire for reducing fuel loads on the forest floor during autumn rather than spring to minimise possible short-term impacts on surface-active Coleoptera.     

EIGHTH TRIENNIAL CONFERENCE—ADELAIDE

Physical and chemical properties of litter and soil of two adjacent stands of high quality jarrah forest, one unburned since 1937, the other burned periodically during the past 40 years and last burned in Spring 1981, were compared in 1982 and 1983. Sampling of the larger elements of the invertebrate fauna was by litter and soil coring and pitfall-trapping three times during 1983.

Most of the soil properties studied had higher values in the burned stand, suggesting that repeated low intensity fires do not deplete jarrah forest soils of nutrients. Periodic low intensity fires had little impact on the frequency of occurrence or capture of the invertebrate fauna studied.     

JARRAH STEM DISTRIBUTIONS

Laboratory bioassays were conducted on the susceptibility of air-dried sapwood specimens, from trees of both regrowth and mature karri (Eucalyptus diversicolor) and jarrah (Eucalyptus marginata), to attack by the powder post borer (Lyctus brunneus). The susceptibility of regrowth karri was determined using material collected from 10 trees (five trees x two areas) each at three positions (the butt, midway along the bole and the crown). Material from the butts of 64 mature trees, representing three different areas in the south west of Western Australia, was similarly assessed. Both regrowth and mature karri specimens were collected from trees within the main karri estate. The susceptibility of both regrowth and mature jarrah was compared concurrently in a bioassay which evaluated butt specimens of approximately 20 trees from each of three different areas in the jarrah forest. Prior to the bioassays, all specimens were assessed for starch concentration in the sapwood.

Some sapwood specimens of both regrowth and mature karri were susceptible to attack by L. brunneus. Specimens cut from the butt position of regrowth karri trees contained the highest concentration of starch and were more heavily attacked by L. brunneus. Similarly, some regrowth and mature jarrah specimens from some areas were susceptible to attack.

Differences in starch concentration and susceptibility between areas from which each timber species was harvested were revealed. Positive correlations, between starch concentration and susceptibility of mature karri and regrowth and mature jarrah, were obtained. A revision of previously published ratings for both karri and jarrah is recommended. We further recommend that a re-assessment of the susceptibility to L. brunneus of all commercially available hardwood timber species be undertaken, particularly if a regrowth resource of those species is being utilised or likely to be utilised in the near future.     

The recognition of heterogeneity and restricted endemism in the management of forested ecosystems in south-western Australia

This paper seeks to refine issues of biodiversity conservation in the context of the exploitation and management of heterogeneous forested ecosystems in south-western Australia. An appropriate spatial scale that accounts for levels of endemism, refugiai habitats and relictual biota will also allow variation to be portrayed between the community types in which the main south-western timber species, jarrah (Eucalyptus marginata) and karri (E. diversicolor) occur. The greater intensity and extent of disturbances since European settlement urges that interactions between agents of disturbance be recognised in forest management. Application of the precautionary principle, and the recognition of fine-scale environmental variation, will allow for more effective management of public lands. There is a need to consider a range of taxa when considering biodiversity gradients or choosing indicator taxa to monitor forest disturbance. We recommend a collaborative, multidisciplinary, cross-institutional approach to understanding biological patterns and processes. This may also allow interactions and change to be more effectively monitored. Adherence to credible scientific practices including willingness to debate, publish and peer review would also contribute to greater co-operation in the management of public lands in south-western Australia.     

Silvicultural impacts in jarrah forest of Western Australia: synthesis,evaluation, and policy implications of the Forestcheck monitoring project of 2001–2006

This paper, the final in a series of ten papers that report the impact of silvicultural treatments (harvesting and associated burning) in jarrah (Eucalyptus marginata) forest, reviews these papers and explores similarities and disparities. More than 2500 species were processed, dominated by macro-invertebrates, vascular flora and macrofungi. Few significant impacts were evident, and most species groups were resilient to the disturbances imposed. Regeneration stocking did not meet specified standards on two gap release and seven shelterwood grids subjected to silvicultural treatment in the period 1988–2002. Six treated grids had a retained basal area of more than 18 m² ha^?1, which obviated the need for further regeneration. More than 50 y may be needed for biological processes to reverse the increase in bulk density of soil caused during harvesting. Cryptogams (especially lichens) were the species group most sensitive to disturbance, although recovery of species richness was nearly complete 10 y after disturbance. For cryptogams and vascular flora, species recorded in only one grid (singletons) were more likely to occur on reference grids than on silviculturally treated grids. For all species groups studied, the imprint of harvesting 40 or more years earlier on species composition had become indistinguishable from that on grids never harvested. Soil nutrient status correlated with species richness for fungi on wood (negatively), light-trapped invertebrates (positively), birds (positively) and terrestrial vertebrates (frogs, reptiles and mammals, negatively). Silvicultural disturbance (timber harvesting and associated burning) correlated with species richness for fungi on wood (positively), terrestrial vertebrates (positively) and cryptogams (negatively). Time since the last (prescribed) fire did not correlate with any species group. Plant disease decreased species richness of light-trapped invertebrates by about 35%. Very few taxa were sufficiently widespread or sufficiently responsive to silvicultural disturbance to be of value as bio-indicators, demonstrating the superiority of biodiversity monitoring over bio-indicator monitoring. It is recommended that FORESTCHECK be expanded into a biological survey of the lower south-west of Western Australia.     

Gum leaf skeletoniser moth,Uraba lugens,in the forests of Western Australia

Uraba lugens defoliated large areas of eucalpyt forest in the south west of Western Australia in January 1983 and extensive infestations continued each year up to the 1985/86 summer when 160 000 ha were affected. In Western Australia the pupation and oviposition behaviour, the life cycle and the host preferences of this indigenous moth differ from those recorded for coastal, inland and highland forms in eastern Australian States. Oviposition occurs in parallel rows as is the case with the eastern Australian lowland form, and like the eastern highland form there is only one generation per year. The larvae have been recorded on Eucalyptus marginata (jarrah), E. calophylla (marri), E. diversicolor (karri), E. rudis (flooded gum), E. decipiens (limestone marlock) and E. wandoo (wandoo).     

Thirteen year results from a Spotted Gum provenance trial in the Wellington catchment of Western Australia

The response of invertebrates to silvicultural treatments (including timber harvesting and post-harvest burning) was examined as part of the FORESTCHECK monitoring project in the jarrah (Eucalyptus marginata) forest of south-west Western Australia. Invertebrates were collected twice yearly (spring and autumn) at 48 sample grids in four jarrah forest ecosystems, which included two different vegetation complexes within the same ecosystem. Grids represented examples of unharvested forest (reference) and forest subject to gap release and shelterwood/selective cut treatments. Collection methods included light trapping, pitfall trapping and hand sampling. A total of 56 705 invertebrate specimens comprising 1497 morphospecies were collected. Within each forest ecosystem, species richness did not differ significantly between gap release, shelterwood/selective cut and reference forest. Estimated total richness of macro-invertebrates varied with silvicultural treatment and collection method: 630 species for pitfall trapping and 1095 for light trapping. Estimated richness from light trapping of grids in unharvested forest was 892 species, compared with 780 species in shelterwood/selective cut and 665 species in gap release treatments. Collection method influenced the direction and magnitude of changes in estimated richness following timber harvesting and post-harvest burning, indicating that multiple collection methods are needed to assess invertebrate response to disturbance. Based on combined capture methods, estimated whole bioregional richness of macro-invertebrate morphospecies was highest in reference forest (1783), intermediate in forest subject to shelterwood/selective cut treatment (1652) and lowest in forest subject to gap release (1527 morphospecies). Greater richness estimates in reference forest are attributable to a greater proportion of macro-invertebrate species that occurred in only one grid. However, the robustness of comparisons between treatments of these bioregional estimates of richness is compromised by inadequate sampling. In contrast, for equivalent sampling effort, species accumulation was slightly greater in silviculturally treated forest than in reference forest, implying that silviculturally treated grids had a more homogenous species composition. Data were analysed using non-metric multidimensional scaling ordination and canonical analysis of principal co-ordinates (CAP) analysis. Invertebrate assemblage composition and abundance were strongly influenced by biogeographic pattern, as represented by forest ecosystem/year of collection (these factors were confounded in the design of the monitoring project). No significant effects of silvicultural treatments on morphospecies composition were detected using CAP analysis of morphospecies abundance. Retention of patches of unharvested forest adjacent to harvested forest will assist in maintaining invertebrate biodiversity at the landscape scale. The data suggest that indicator species may be of limited value for monitoring recovery after disturbance in the jarrah forest bioregion because of substantial species turnover between different forest ecosystems and years of sampling. Monitoring of invertebrates should be continued to demonstrate whether harvested coupes are sufficiently heterogeneous, so that their contribution to bioregion species diversity is equivalent to that of unharvested areas.     

A FIELD METHOD FOR DETERMINING SOIL MOISTURE

The Forests Department of Western Australia has directed particular attention over the past fifteen years to the development of an adequate fire control organisation for the protection of large areas of regenerated forest and plantations, in addition to extensive tracts of virgin Eucalypt forest which are supporting a large sawmilling industry. Extensive controlled burning of firebreak belts and dangerous hazards is carried out annually during the spring and autumn months, and during the fire danger season outbreaks of fire occurring in and around State Forests under intensive management are immediately suppressed.

Early and accurate detection, rapid access to all parts of the forest, and the employment of trained, experienced fire fighters form the basis of successful supppression. Eighteen towers, four tree lookouts and a number of houses on vantage points in the forest provide facilities for accurate detection; the main routes of access embrace 2,260 miles of forest roads and 5,780 miles of trafficable firelines; 1,030 miles of departmental telephone line and 490 telephones arc used for communication, while twenty-four departmental motor trucks arc equipped with water supplies and fire fighting implements and are constantly available in the summer months for the transport of field working parties engaged in silvicultural work. These workmen, who are trained in fire suppression methods, are provided with home and school facilities for their families in small settlements established in the forests.

Valuable assistance in fire suppression is rendered by local settlers and timber workers, and provision is made for their transport by hired vehicles, and the supply of standard departmental fire fighting equipment. These volunteers are given training in the use of equipment and fire fighting methods at the commencement of each fire season.

Annual fire losses during the last few years have been confined to less than 0.03% of the area protected.     

Responses of foraging ant populations to high-intensity wildfire,salvage logging and natural regeneration processes in Eucalyptus regnans regrowth forest of the Victorian Central Highlands

The effects of high-intensity wildfire plus salvage logging and fire-induced natural regeneration processes on foraging ants (Formicidae) were assessed in multiple-use Eucalyptus regnans (Mountain Ash) regrowth forest approximately 60 km east of Melbourne in the Victorian Central Highlands. The study was based on 35 912 ant specimens, and on 69 493 epigeal non-ant arthropods of 27 taxa, contained in 2,160 pitfall trap samples collected at three sites over a single pre-fire year and two post-fire years.

Twenty ant species of sub-families Dolichoderinae, Formicinae, Myrmeciinae, Myrmicinae and Ponerinae were identified, but only Notoncus spinisquamis, Myrmecia pilosula and Chelaner sculpturatus could be validated. Two species were placed into the newly erected genus OcheteUus (Dolichoderinae), and one species of Myrmicinae could not be identified below sub-family rank. The biology and taxonomy of the majority of these species is uncertain, although the most commonly trapped ant, Prolasius? pallidus, is a recognised seed harvester, and two other species of Prolasius plus C. sculpturatus are suspected seed harvesters. The second most frequently trapped species, Iridomyrmex? foetans, is a carnivore and scavenger. Chelaner sculpturatus was the most frequently trapped among 18 “minor” species.

The rapid replacement of the ecologically complex regrowth forest by young even-aged regeneration of E. regnans through wildfire effects and salvage logging caused a substantial increase in foraging activity of P. pallidus during the first post-fire autumn period, and activity remained high for up to 14 months depending on elevation of the forested landscape. Activity of I. foetans declined immediately after the fire, but eight months later it was significantly higher than “control plot” levels for up to four months. The response of the less frequently trapped “minor” species to the wildfire, logging and regeneration processes remained uncertain because of the low numbers trapped before and after the fire. Prolific regeneration of E. regnans emerged in the burnt forest, suggesting that fire-induced seed fall was sufficiently large and extensive to have caused predator satiation. The implications of this for artificial regeneration programs in E. regnans forest are discussed.     

PRODUCER GAS IN WESTERN AUSTRALIA

A survey was undertaken lo assess 5 to 10-year-old rehabilitated bauxite minesite vegetation as suitable habitat for birds while breeding during spring in the jarrah (Eucalyptus marginata) and marri (E. calophylla) forest at Jarrahdale. Western Australia. The minesites had been rehabilitated and revegetated with local shrub species and a mix of local and eastern eucalypts resistant to the root rot fungus Phytophthora cinnamomi.

Twenty-one species of birds used the former minesites for foraging or hunting while breeding; twelve of these were found nesting or rearing fledglings in the revegetation. Among the breeders were four understorey dwelling species which were otherwise uncommon in surrounding upland forest or (in two cases) confined in stream zone undergrowth. Total densities of all pairs or groups breeding in minesites were similar to those in nearby forest. Breeding territories often spanned areas of both minesite and forest around the edge of pits.

Eleven other species were found breeding only in the adjacent forest and all were nesting in sites as yet unavailable within minesites, such as tree hollows, fissures, bark crevices and crown foliage. The possible use of nest-boxes to aid in the early provision of sites for hollow-nesting species is being investigated.