The importance of ecological scale for wildlife conservation in naturally fragmented environments: A case study of the Brush-Tailed Rock-Wallaby (Petrogale Penicillata)

Determining the ecologically relevant spatial scales for predicting species occurrences is an important concept when determining species–environment relationships. Therefore species distribution modelling should consider all ecologically relevant spatial scales. While several recent studies have addressed this problem in artificially fragmented landscapes, few studies have researched relevant ecological scales for organisms that also live in naturally fragmented landscapes. This situation is exemplified by the Australian rock-wallabies’ preference for rugged terrain and we addressed the issue of scale using the threatened brush-tailed rock-wallaby (Petrogale penicillata) in eastern Australia. We surveyed for brush-tailed rock-wallabies at 200 sites in southeast Queensland, collecting potentially influential site level and landscape level variables. We applied classification trees at either scale to capture a hierarchy of relationships between the explanatory variables and brush-tailed rock-wallaby presence/absence. Habitat complexity at the site level and geology at the landscape level were the best predictors of where we observed brush-tailed rock-wallabies. Our study showed that the distribution of the species is affected by both site scale and landscape scale factors, reinforcing the need for a multi-scale approach to understanding the relationship between a species and its environment. We demonstrate that careful design of data collection, using coarse scale spatial datasets and finer scale field data, can provide useful information for identifying the ecologically relevant scales for studying species–environment relationships. Our study highlights the need to determine patterns of environmental influence at multiple scales to conserve specialist species such as the brush-tailed rock-wallaby in naturally fragmented landscapes.

Mapping and characterising subtropical estuarine landscapes using aerial photography and GIS for potential application in wildlife conservation and management

Coarse-resolution thematic maps derived from remotely sensed data and implemented in GIS play an important role in coastal and marine conservation, research and management. Here, we describe an approach for fine-resolution mapping of land-cover types using aerial photography and ancillary GIs and ground data in a large (100 x 35 km) subtropical estuarine system (Moreton Bay, Queensland, Australia). We have developed and implemented a classification scheme representing 24 coastal (subtidal, intertidal. mangrove, supratidal and terrestrial) cover types relevant to the ecology of estuarine animals, nekton and shorebirds. The accuracy of classifications of the intertidal and subtidal cover types, as indicated by the agreement between the mapped (predicted) and reference (ground) data, was 77-88%, depending on the zone and level of generalization required. The variability and spatial distribution of habitat mosaics (landscape types) across the mapped environment were assessed using K-means clustering and validated with Classification and Regression Tree models. Seven broad landscape types could be distinguished and ways of incorporating the information on landscape composition into site-specific conservation and field research are discussed. This research illustrates the importance and potential applications of fine-resolution mapping for conservation and management of estuarine habitats and their terrestrial and aquatic wildlife. (c) 2005 Elsevier Ltd. All rights reserved.

Predictive distribution models and their application in wildlife conservation

Wildlife managers are often faced with the difficult task of determining the distribution of species, and their preferred habitats, at large spatial scales. This task is even more challenging when the species of concern is in low abundance and/or the terrain is largely inaccessible. Spatially explicit distribution models, derived from multivariate statistical analyses and implemented in a geographic information system (GIS), can be used to predict the distributions of species and their habitats, thus making them a useful conservation tool. We present two such models: one for a dasyurid, the Swamp Antechinus (Antechinus minimus), and the other for a ground-dwelling bird, the Rufous Bristlebird (Dasyornis broadbenti), both of which are rare species occurring in the coastal heathlands of south-western Victoria. Models were generated using generalized linear modelling (GLM) techniques with species presence or absence as the independent variable and a series of landscape variables derived from GIS layers and high-resolution imagery as the predictors. The most parsimonious model, based on the Akaike Information Criterion, for each species then was extrapolated spatially in a GIS. Probability of species presence was used as an index of habitat suitability. Because habitat fragmentation is thought to be one of the major threats to these species, an assessment of the spatial distribution of suitable habitat across the landscape is vital in prescribing management actions to prevent further habitat fragmentation.

Conservation ecology and breeding biology of the white-browed treecreeper, Climacteris affinis

The White-browed Treecreeper Climacteris affinis is one of many woodland-dependent birds that are at risk from the encroachment of human-dominated land-uses into natural landscapes. The White-browed Treecreeper inhabits semi-arid woodlands in north-west Victoria, Australia, a vegetation community that has undergone extreme modification in the last century due to the expansion of agriculture in the region. Extant woodlands represent only 10% of the original woodland cover in the region, and are highly fragmented and disturbed in many districts. Thus, the survival of the White-browed Treecreeper may depend on active management. However, current knowledge of the ecology and biology of this species is virtually non-existent, and inadequate for informed and effective conservation actions. The aim of this thesis is to redress this situation and provide the ecological basis for sound conservation management of the species. The thesis consists of two parts: an investigation of habitat use at three spatial scales and a study of the social organization, nesting requirements, breeding behaviour and reproductive success of a population of White-browed Treecreepers. Fifty-six patches of remnant woodland in north-west Victoria were surveyed to determine the factors affecting the occurrence of the White-browed Treecreeper at the regional scale. It was detected in 16 patches, and was largely confined to two core districts - Yarrara and, Wyperfeld (Pine Plains). The floristic composition of the dominant tree species was an important determinant of patch occupancy, with the results providing quantitative support for the previously suspected affinity for Belah Casuarina pauper and Slender Cypress-pine Callitris gracilis — Buloke Allocasuarina luehmannii woodlands. However, the absence of the White-browed Treecreeper from several districts was due to factors other than a lack of appropriate habitat. Demographic isolation - the distance from the focal patch to the nearest population of the White-browed Treecreeper - was the most important variable in explaining variation in patch occupancy. Patches isolated from other treecreeper populations by more than 8.3 km in landscapes of non-preferred native vegetation, and 3 km in agricultural landscapes, were unlikely to support the White-browed Treecreeper. The impact of habitat loss and fragmentation on the capacity of individuals to move through the landscape (i.e. functional connectivity) is considered in relation to disruption to dispersal and migration, and the potential collapse of local metapopulations. Habitat use was then examined in a network of patches and linear strips of Belah woodland embedded in a predominantly cultivated landscape. A minimum area of 18.5 ha of Belah woodland was identified as the most important criterion for patch occupancy at the local scale. This landscape appeared to be permeable to movement by the White-browed Treecreeper, facilitated by the extensive network of linear habitat, and clusters of small to medium fragments. The third scale of habitat use investigated the frequency of use of 1-ha plots within tracts of occupied woodland. It is important to discriminate between habitat traits that operate at the population level, and those that act as proximate cues for habitat selection by individuals. Woodlands that have high tree density, extensive cover of low-stature shrubs, abundant lichen, a complex vertical structure, and relatively low cover of grass and herbs are likely to support larger populations of the White-browed Treecreeper. However, individuals appeared to be using tree dominance (positive) and tall shrub cover (negative) as proximate environmental stimuli for habitat selectivity. A relatively high cover of ground lichen, which probably reflects a ground layer with low disturbance and high structural complexity, was also a reliable indicator of habitat use. Predictive models were developed which could be used to plan vegetation management to enhance habitat for the White-browed Treecreeper. The results of the regional, landscape and patch-scale investigations emphasise that factors operating at multiple spatial scales influence the suitability of remnant vegetation as habitat for the White-browed Treecreeper. The White-browed Treecreeper is typical of many small Australian passerines in that it has high annual survival, small clutches, a long breeding season, multiple broods and relatively low reproductive rates. Reproductive effort is adjusted through the number of clutches laid rather than clutch size. They occupy relatively large, all-purpose territories throughout the year. However, unlike many group territorial birds, territory size was not related to the number of occupants. The White-browed Treecreeper nests in tree hollows. They select hollows with a southerly orientation where possible, and prefer hollows that were higher from the ground. At Yarrara, there was considerable spatial variation in hollow abundance that, in concert with territorial constraints, restricted the actual availability of hollows to less than the absolute abundance of hollows. Thus, the availability of suitable hollows may limit reproductive productivity in some territories, although the magnitude of this constraint on overall population growth is predicted to be small. However, lack of recruitment of hollow-bearing trees would increase the potential for hollow availability to limit population growth. This prospect is particularly relevant in grazed remnants and those outside the reserve system. Facultative cooperative breeding was confirmed, with groups formed through male philopatry. Consequently, natal dispersal is female-biased, although there was no skew in the sex ratio of the fledglings or the general adult population. Helpers were observed performing all activities associated with parenting except copulation and brooding. Cooperatively breeding groups enjoyed higher fledgling productivity than simple pairs, after statistically accounting for territory and parental quality. However, the difference reflected increased productivity in the 1999-breeding season only, when climatic conditions were more favourable than in 1998. Breeding commenced earlier in 1999, and all breeding units were more likely to attempt a second brood. However, only breeders with helpers were successful in fledging second brood young, and it was this difference that accounted for the overall discrepancy in productivity. The key mechanism for increased success in cooperative groups was a reduction hi the interval between first and second broods, facilitated by compensatory reductions in the level of care to the first brood. Thus, females with helpers probably achieved significant energetic savings during this period, which enabled them to re-lay sooner. Furthermore, they were able to recommence nesting when the fledglings from the first brood were younger because there were more adults to feed the dependent juveniles. The current utility, and possible evolutionary pathways, of cooperative breeding is examined from the perspective of both breeders and helpers. Breeders benefit through enhanced fledgling productivity in good breeding conditions and a reduction in the burden of parental care, which may impart significant energetic savings. Further, breeders may facilitate philopatry as a means for ensuring a minimum level of reproductive success. Helpers benefit through an increase in their inclusive fitness in the absence of opportunities for independent breeding (i.e. ecological constraints) and access to breeding vacancies in the natal or adjacent territories (i.e. benefits of philopatry). However, the majority of breeding unit-years comprised unassisted breeders, which suggests that pairs are selectively favoured under certain environmental or demographic conditions.

Contribution of multi-tenure reserve networks to biodiversity conservation

A consistent and integrated approach to nature conservation across the landscape and regardless of tenure is widely recognised as essential in ensuring the effective conservation of biodiversity. 'Multi-tenure reserve networks', which incorporate public and private lands managed for conservation, are considered a means of achieving landscape scale conservation. Biosphere Reserves (BR) and Conservation Management Networks (CMN) are characteristic models in Australia. This thesis aims to evaluate the role of such networks in protecting biodiversity, specifically by: (1) analysing the spatial configuration (size, shape, connectivity) of networks and their individual components; (2) evaluating the contribution of networks (in real terms and in reporting procedures) to biodiversity conservation objectives; (3) analysing the influence of the attitudes and perceptions of land managers on the functionality of networks; and (4) evaluating the influence of coordinating bodies on network functionality. In order to account for deficiencies in existing classifications of conservation lands, a new classification system was developed for this thesis - the Conservation Lands Classification. This classification incorporates conservation mechanisms on public and private lands and forms the basis for comparing network components in three Australian case studies - the Bookmark BR located in the Murray Mallee of South Australia, the Gippsland Plains CMN on the eastern Gippsland Plains of Victoria and the Grassy Box Woodlands CMN across the inland slopes of New South Wales. The spatial configuration of individual components within networks was measured using spatial analysis techniques within a geographic information system (GIS). GIS was also used to measure the contribution that networks made to a comprehensive, adequate and representative reserve system through the ecosystems they protected. The attitudes and perceptions of landowners and managers within the networks were obtained using questionnaires. Questionnaires were also sent to network coordinators. Statistical and descriptive analysis was conducted on the results. The sizes of individual components varied markedly between the three networks, however within each network public reserves were on average larger than private conservation lands. Although levels of physical connectivity varied between networks, Bookmark BR and Gippsland Plains CMN showed greater similarity to each other than to the Grassy Box Woodlands CMN. The findings raise important questions about the real and perceived differences in the BR and CMN models. All networks, and particularly those components outside the public protected area estate, contributed to enhancing the protection of ecosystems unrepresented or under-represented in the reserve system, although the extent of this contribution varied between networks. Trade-offs between reserve design efficiency and a contribution to a comprehensive, adequate and representative reserve system were evident between networks. Bookmark BR was characterised by high connectivity, strong reserve design integrity but a lower contribution to protecting under-reserved ecosystems, whereas the opposite was evident in the Grassy Box Woodlands CMN. Over 88% of managers considered their involvement in multi-tenure reserve networks to be a positive or very positive experience. A lack of resources and time for management were considered major limitations of these networks. The majority (80%) of private land managers within networks were willing to be included in a national reserve system of conservation lands. This has important implications for the Australian National Reserve System, which currently incorporates mostly public land. The changing nature of the network coordination arrangements suggests an organic fluid evolution of network structures is likely, contrasting with the desire for legalistic and administrative rigidity promoted by government agencies. The thesis concludes that all the networks studied contribute in varying degrees to biodiversity conservation. The key factors influencing the current and potential contribution that such networks make are: (1) the aims, directions and restrictions set by or imposed upon the coordinating body; and (2) the biophysical nature of the surrounding bioregion and resultant historical land use and tenure pattern. Although the successful operation of such 'multi-tenure' networks ultimately relies on the willing participation of private landholders, ongoing institutional support is likely to be required for maintaining networks in the longer term. Considering networks are increasingly formed outside of the influence of government institutions, this presents a significant challenge for effective coordinated conservation.

Waterfowl decline in the Mississippi Flyway [microform] : hearing before the Subcommittee on Fisheries and Wildlife Conservation and the Environment of the Committee on Merchant Marine and Fisheries, House of Representatives, One Hundredth Congress, second session, on the decline of waterfowl in the Mississippi Flyway and the loss of wintering habitat in the Mississippi Flood Plain, September 22, 1988.

"Serial no. 100-91."

Fish and wildlife conservation in river basin development.

Mode of access: Internet.

Fish and wildlife conservation act of 1980 and authorizations for wildlife refuges [microform] : hearing before the Subcommittee on Resource Protection of the Committee on Environment and Public Works, United States Senate, Ninety-sixth Congress, second session, on S. 2181 ... February 4, 1980.

Reuse of record except for individual research requires license from Congressional Information Service, Inc.

Aquaculture : joint hearings before the Subcommittee on Fisheries and Wildlife Conservation and the Environment and the Subcommittee on Oceanography of the Committee on Merchant Marine and Fisheries, House of Representatives, Ninety-fourth Congress, first and second sessions ....

Mode of access: Internet.

Fishery conservation and management act [microform] : hearings before the Subcommittee on Fisheries and Wildlife Conservation and the Environment of the Committee on Merchant Marine and Fisheries, House of Representatives, Ninety-sixth Congress, first session ....

Reuse of record except for individual research requires license from Congressional Information Service, Inc.

Development and expansion of the natural resource data and information systems in support of the Illinois Comprehensive Wildlife Conservation Plan : annual segment report 2005 /

Submitted to Illinois Department of Natural Resources.