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Fruit bodies of hypogeous fungi are an important food source for many small mammals and are consumed by larger mammals as well. A controversial hypothesis that prescribed burning increases fruiting of certain hypogeous fungi based on observations in Tasmania was tested in the Australian Capital Territory to determine if it applied in a quite different habitat. Ten pairs of plots, burnt and nonburnt, were established at each of two sites prescribe-burnt in May 1999. When sampled in early July, after autumn rains had initiated the fungal fruiting season, species richness and numbers of fruit bodies on the burnt plots were extremely low: most plots produced none at all. Both species richness and fruit body numbers were simultaneously high on nonburnt plots. One of the sites was resampled a year after the initial sampling. At that time species richness and fruit body abundance were still significantly less on burnt plots than on nonburnt, but a strong trend towards fungal recovery on the burnt plots was evident. This was particularly so when numbers of fruit bodies of one species, the hypogeous agaric Dermocybe globuliformis, were removed from the analysis. This species strongly dominated the nonburnt plots but was absent from burnt plots in both years. The trend towards recovery of fruit body abundance in the burnt plots one year after the burn was much more pronounced with exclusion of the Dermocybe data. The Tasmanian-based hypothesis was based mostly on the fruiting of two fire-adapted species in the Mesophelliaceae. Neither species occurred on our plots. Accordingly, the results and conclusions of the Tasmanian study cannot be extrapolated to other habitats without extensive additional study. Implications for management of habitat for fungi and the animals that rely on the fungi as a food source are discussed.

Results are presented which prioritize areas for potential protection in Quebec on the basis of biodiversity considerations. These results are relevant to the ongoing public discussion in Quebec about designating new parks and refuges so that the province may fulfil its obligations to Canada's Endangered Spaces Campaign. The prioritization algorithm used in this analysis is based on rarity and complementarity. It attempts to sample biodiversity in as area-efficient a way as possible. The biodiversity surrogates used here comprise a subset of 743 species for which data on spatial distributions are publicly available; the analysis begins with 394 species at risk. It is shown that: (i) the existing network of protected areas in Quebec does a poor job of protecting these biodiversity surrogates; (ii) adding adjacent areas to this network will not be the optimal way of protecting these biodiversity surrogates; (iii) many of the areas that have highest priority are in southern Quebec, which has a high human population density; (iv) because of (iii), designating parks may not be economically or sociologically feasible and more adaptive alternative conservation plans will have to be devised; (v) coastal areas, riparian habitats, and other wetlands should have high priority for protection but are currently very inadequately represented in the reserve network; (vi) there is some reason for concern about the clear-cut logging of boreal forests in northern Quebec; and (vii) the islands, Ile d'Anticosti and the Iles-de-la-Madeleine, emerge as being of very significant conservation value and plans for the protection of areas on them should be an immediate goal for biodiversity conservation in Quebec.

The use of a quantitative population growth model to investigate the persistence of South African elephant populations is explored. The model provides quantitative assessments of population persistence and confidence intervals for estimated parameters based purely on population size estimates. The analysis supports the view that most of the larger populations in the region are secure. This view is further supported by a lack of density dependent effects in most of the recovering populations and the high population rates of increase observed. This predominantly positive prognosis is in contrast with that emerging from most of the rest of the African continent where the populations are under greater threat because of habitat restriction and direct human conflict. This preliminary assessment of elephant population persistence suggests that “viable” populations may lie between 400 and 6000 individuals. Although not inconsistent with information-greedy genetic and demographic models, the relationship between population growth versus genetic and demographic models should be further investigated. The implementation of a metapopulation management strategy towards these smaller populations is advocated. In addition, as all of the populations included in this analysis have been afforded some degree of protection since the 1920s, continued protection would be a prerequisite for their continued survival.

We respond to Oksanen's recent comments in “Why the beta-function cannot be used to estimate skewness of species responses”. We agree with Oksanen's criticisms concerning correlated parameters when fitting beta-functions. We argue that response functions can be reasonably estimated using beta-functions only for those species whose range limits obviously fall within the observed length of an environmental gradient and our original description included explicit recognition of this need. The simulated data used by Oksanen contains only one species that would meet our criteria for defining the limits and the shape of this species is recovered by fitting a beta-function. Beta-functions are shown to recover reasonable approximations of the true shapes when fitted to simulated data, generated without error, and representing species with either skewed or symmetrical response shapes if using realistic estimates of the species limits. When arbitrary limits are imposed then distorted shapes result. Using similar data from 500 simulated data sets generated under the assumption of a Poisson error structure, beta-functions gave conservative estimates of the degree of skewness for those data sets representing skewed species and no evidence of skewness for those data sets representing symmetrical species. We conclude that despite Oksanen's concerns the conclusions drawn by the current authors and colleagues with respect to the degree of skewness shown by species response functions along a common gradient are robust to the fitting procedures used. While we agree that the fitting of beta-functions is not the best approach to modelling skewed responses we argue that it will not mislead the user as to the presence or extent of skewness if used with reasonable and data driven estimates of the species limits.

Iterative reserve selection algorithms were applied to two mammal databases, generalized to sixteenth degree grid squares, for the Transvaal region of South Africa. Based on primary point data, 24 grid squares are required to represent all species at least once, while only 13 grid squares are required when based on distribution map data; only two of these grid squares are common to both analyses. As the number of representations per species is increased from one to five, the number of selected grid squares increased to 86 and 71 or 72 respectively, with only 17 of these common to both analyses. These differences in the selection of sites are further reflected in the degree of congruence between selected grid squares and existing conservation areas which is on average 63.3% for grid squares selected from the primary database and only 42.5% for those selected from the distribution map database. These results emphasize the importance of quality data input when evaluating regional reserve networks. Highly generalized distribution map data sets, on the one hand, are extrapolations of limited data sets and contain non-quantifiable levels of false-positives which could have significant implications if used for establishing regional reserve networks. On the other hand, although there are problems associated with the establishment of primary diversity databases, namely data currency and uneven and non-random sampling (leading to false negatives), they remain our most reliable option for assigning conservation value.

Plant species recorded from two surveys of the Ingleborough limestone pavements in the U.K. 11 years apart, in 1974/75 and 1985, are used to assess the performance of potential reserve networks over time. The minimum set of pavements needed to represent all nationally rare and uncommon species occurring on the pavements in 1974/75 is inadequate in 1985 because of a very high level of apparent turnover in species composition. The number of species lost or gained is not correlated with pavement area and the turnover has not resulted in an equilibrium number of species; overall more species were lost than gained. Even if this turnover is due only to observer bias, it is a real phenomenon when it comes to land use decision-making and should be taken into account when planning reserve networks and developing conservation management strategies. A statistical model of extinction probability is derived by relating the variable “extinct or not in 1985” to frequency of occurrence in 1974/75 using logistic regression. This model is then used to predict that 18, 19, or 20 and 21 species will have become locally extinct by 1994, 1995, and 1996, respectively. The list of species from which these extinctions are likely to be drawn is supplied. Especies de plantas registradas en dos estudios de los pavimentos de piedra caliza de Ingleborough en el Reino Unido, espaciados por 11 anos, en 1974/75 y 1985, son utilizados para evaluar el desempeno de una red potencial de reservas a traves del tiempo. La cantidad minima de pavimentos necesarios para representar todas las especies raras y no-comunes en forma nacional en los pavimentos de 1974/75 es inadecuada en 1985 debido a un nivel muy alto de recambio (“turnover”) aparente en composiscion de especies. El numero de especies ganado o perdido no esta correlacionado con el area pavimentada y el recambio no ha resultado en un numero equilibrado de especies; en general mas species se han perdido que ganado. Aun si este recambio es debido solo al sesgo del observador, es un fenomeno real cuando se trata de tomar decisiones sobre manejo de la tierra y debe ser tenido en cuenta cuando se planean redes de reservas y se desarrollan estrategias de manejo de conservacion. Se deriva un modelo estadistico de probabilidad de extincion relacionando la variable “extinto o no en 1985” con la frecuencia de ocurrencia en 1974/75 y usando una regresion logistica. Este modelo es posteriormente usado para predecir que 18, 19 o 20 y 21 especies habran de extinguirse localmente en 1994, 1995 y 1996 respectivamente. Se adjunta la lista de especies a partir de la cual estas extinciones seran probablemente obtenidas.

A new reserve selection algorithm is proposed which minimises the possibility of widely dispersed sites being selected by including a rule to select the nearest site when sites are otherwise equal. The algorithm also minimises the number of order-dependent selections. A comparison between two solutions, one with and one without the rule to choose the nearest site, when there is a choice, shows that there is a cost associated with including that rule. It is argued, however, that a more sensible and manageable spatial arrangement for a nominal reserve network is derived by including that rule.

Scoring criteria used in conservation evaluation can be measured using interval or ratio values (scores) or ordinal values (score classes). The choice of either scores or score classes can markedly influence the efficiency of scoring criteria, i.e. the number or area of highest scoring sites required to represent all natural features, and therefore the likelihood of achieving a network of reserves which is fully representative. The effect on efficiency of choosing scores or score classes differes with the scoring criterion being used and with the data set from which the sites are drawn and is difficult to predict a priori .

The cost of surveys, both in terms of dollars and manpower, will prevent total inventories of complete regions being completed, if in fact ever undertaken, before decisions have to be made to change current land use practices. There exists a need to be able to extrapolate existing location-specific information over complete regions with increased confidence in the subsequent spatial predictions. Recent developments in statistical modelling provide methods appropriate to many types of biological data and taken together with the application of regression-diagnostic techniques offer the biologist or land manager improved, in terms of reliability and spatial completeness, species distribution data bases on which to base conservation decisions. This paper describes one component of such development and the application of three regression-diagnostic techniques: the use of residuals to test the statistical assumptions implicit in the fitted regression model; the use of estimates of potential influence each observation has on the fitted model; and the use of the coefficient of sensitivity of the model to individual observations. Guidelines are given to assist with the construction of a predictive model from a group of potential explanatory or predictor variables. The use of generalised linear regression models and regression diagnostics is discussed in terms of their impact on survey design.

Scoring and iterative approaches to wildlife conservation evaluation were compared in terms of their contribution to the conservation of all natural environments or species. This contribution was termed efficiency and was calculated from the number or area of highest scoring sites or the number or area of all sites selected by iterative analyses required to represent all natural environments or species a specified number of times. Efficiency of sampling in reserves is an important consideration in conservation planning if reserve systems are to become fully representative before the options for protection are exhausted. Scoring criteria varied greatly in their efficiencies but were consistently less efficient than the iterative analyses.

We examine the relationship between the number of bird species and environment within 500 000 ha of eucalypt forests in south-eastern New South Wales, Australia. Birds were surveyed at 39 sites within 31 eucalypt communities, which were, in turn, scored by altitude, temperature, rainfall, basal areas of trees and levels of the nutrients nitrogen, phosphorus, potassium and magnesium in the eucalypt foliage. Ninety bird species were recorded. Numbers per site, averaged over the whole sample period, ranged between 20 and 38 over all surveys, 24 and 42 in ‘summer’ (October to March) when migrant species were present, and 13 and 38 in ‘winter’ (April to September). A forward stepwise Poisson regression model was used to fit bird species richness to the environmental variables. Over all surveys and in ‘summer’, foliar magnesium and tree basal area (including the basal area of dead trees) were significantly (positive) correlated with the number of bird species. In ‘winter’ the correlations were with altitude and temperature (both negative), presumably the result of emigration of species that avoid cold weather, and tree basal area (positive). The positive association of number of species over all surveys and in ‘summer’ with tree basal area, including dead trees, and foliar magnesium may index the level of forest maturity and productivity. Forest management directed solely to timber production reduces the basal area and the number of dead trees and may thereby reduce bird species richness permanently. A methodology is offered, based on the relationship between the physical environment and the more productive eucalypt communities, for determining forest areas containing the most species of birds.

An iterative analysis was used to identify the number and area of pastoral properties needed to contain the full range of natural environments (land systems) in part of western New South Wales. A minimum of 32 properties (3·1% of total number) and 7980 km 2 (5·7% of total area) was required to represent every land system at least once. Full representation required a greater overall number and area when the analysis began with properties already acquired for conservation. Excluding land systems atypical of the study area did not greatly reduce the number and area of properties required. Complete representation of land systems in each geographical subdivision in which they occur required a much greater overall number and area of properties than when the analysis was run for the study area as a whole. The algorithm used in this study produced very similar results to other iterative analyses applied to reserve selection in Australia.