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Globally, the impacts of anthropogenic climate change can displace species into more favourable climates. Semi‐arid desert specialists, such as the sandhill dunnart, Sminthopsis psammophila, are typically susceptible to rainfall deficits, wildfires and extreme temperatures caused by anthropogenic climate change. We first used maximum entropy (MaxEnt) species distribution models (SDMs) to predict the current distribution of S. psammophila. Between 2016 and 2018, we ground validated the model's predictions throughout Western Australia, confirming S. psammophila in 18 locations in which it was predicted to occur. The predicted distribution of S. psammophila appears mostly constrained to within its known range. However, S. psammophila was verified 150 km north of its range in Western Australia and connectivity between the South Australian populations was correctly predicted. In 2019, we used updated occurrence data to project SDMs for S. psammophila during the mid‐Holocene, present day and under two future representative concentration pathways (RCPs) of RCP 4.5 (an optimistic emissions scenario) and RCP 8.5 ("business as usual") for 2050 and 2070. By 2050 (RCP 8.5), almost all Western Australian Great Victoria Desert (WAGVD) habitat is predicted to be unsuitable for S. psammophila. By 2070 (RCP 8.5), the climates of the WAGVD and Yellabinna Regional Reserve populations are predicted to become unsuitable, and the species' geographical range is predicted to contract in Australia by 80%. However, the 2070 (RCP 4.5) scenario predicts that this contraction could be halved. As a sandy desert specialist, the distribution of S. psammophila is geographically limited at its southern bounds due to the cessation of suitable spinifex (Triodia spp.) habitats, and so further extension of the range southwards is not possible. Sympatric desert species may be similarly affected, and we suggest that SDMs will be a useful tool in helping to predict the effects of climate change on their distributions. [ABSTRACT FROM AUTHOR]

Organisms sharing the same habitats may differ in small-scale microhabitat requirements or benefit from different management. In this study, set in Italy, we focused on two species of high conservation value, the cerambycid beetle R osalia alpina and the bat B arbastella barbastellus, which often share the same forest areas and in several cases the same individual trees. We compared the potential distribution and, at two spatial scales, the niches between such species. The predicted distributions largely overlapped between the beetle and the bat. The niches proved to be similar on a broad scale, yet not on the plot one. Compared with B . barbastellus, R . alpina tends to occur at lower altitude in more irradiated sites with lower canopy closure and uses shorter trees with wider diameters. B . barbastellus occurred more often in trees within forest or along its edges, whereas R . alpina lays eggs in trees found in clearings. B . barbastellus plots were more frequent in forest, R . alpina plots in forested pasture and open-shredded forest. Overall, exposure to sun influenced more critically site and tree selection by R . alpina, as a warm microclimate is essential for larval development. Although B . barbastellus reproduction may be favored by warmer roosting conditions, bats may also find such conditions in dense forest and in strongly irradiated cavities high up in tall trees that project above the canopy. We emphasize that subtle differences in the ecological requirements of syntopic taxa could be missed at broad scales, so multiple-scale assessment is always advisable. [ABSTRACT FROM AUTHOR]

A naturally functioning riparian zone is essential for the ecological health of a river, filtering pollutants, supplying organic matter and providing a structural habitat for wildlife. Most lowland rivers would also naturally flood the riparian zone at regular intervals, thereby providing direct inputs of nutrients and water that create additional habitats and breeding opportunities for riverine species. We examined the relationship between the quality of the riparian habitat and foraging and activity of bats (Chiroptera), which are good indicators of ecosystem health. Twenty paired sites in the Rivers Lee and Colne catchments in England were selected to test the hypothesis that degradation in the quality of riparian habitat reduces foraging and activity in bats; paired sites were similar in terms of size, flow rate and water chemistry but differed in the quality of their riparian zones. AnaBat detectors were used to measure bat activity from 30 min before dusk to 30 min after sunrise on the same night at paired sites because recording frequency-divided bat echolocation calls in real time allows large amounts of data to be collected over long time periods in a digitized format. Significantly more feeding buzzes were recorded in sites with better quality riparian zones; no differences in overall bat activity were found between the two habitat types. Pipistrellus pipistrellus and Pipistrellus pygmaeus accounted for 96% of bat passes. Pipistrellus pygmaeus was significantly more active in high quality sites than P. pipistrellus; there was no difference between the two species in poor quality sites. We show that the quality of riparian buffer zones is important for the activity and feeding behaviour of pipistrelle bats. [ABSTRACT FROM AUTHOR]

From 2001 to 2003 we radio tracked 23 Pipistrellus pipistrellus and 23 Pipistrellus pygmaeus to investigate whether there are any differences in foraging behaviour between the two cryptic species during the summer, and to consider whether any differences between these species are important for their conservation planning. There were significant differences between the two species in relation to flying time, mean maximum distances travelled from the roost, numbers of foraging bouts made and span of home ranges. The results suggest that P. pipistrellus makes more flights to a greater number of foraging locations (and possibly) feeding habitats than P. pygmaeus, although these foraging areas are likely to be closer to the roosts. This behaviour is particularly marked during lactation. In contrast, P. pygmaeus spends less time flying, makes fewer foraging bouts but travels further distances, suggesting that this species is selecting specific foraging habitats. These differences in foraging behaviour support the hypothesis that these species occupy different ecological niches, and conservation planners should be aware of these differences when considering the requirements of pipistrelles in the UK. [ABSTRACT FROM AUTHOR]

This paper reviews empirical studies relating communities of coral-reef fishes to the characteristics of the underlying habitat, and the effects of habitat disturbance. Many contrasting patterns in the relationships between fish communities and coral cover, habitat heterogeneity or topographic complexity have been described, including strong effects of particular habitat characteristics (both positive and negative), as well as those finding weak or no relationships. In addition, a whole range of potential responses to different kinds of disturbance, including hurricane damage, crown-of-thorns (Acanthaster planci)outbreaks, and El Nino-associated coral and sea urchin die-offs, have been described. Few workers have attempted to test among alternative models about the importance of resource limitation or responses to disturbance, so critical hypotheses have not been tested. Potential generalizations may be obscured due to a number of problems faced whenmaking comparisons among existing studies. These include the enormous variation in the magnitude of changes to habitats observed, restrictive assumptions about the form of relationships between fish andhabitat variables, inadequate descriptions of habitat and fish community structure, a heavy reliance on `natural', pseudoreplicated experiments and a plethora of different numerical and analytical techniques. We conclude that the search for generalizations would be facilitated by a greater attention to theory and clearer statements of the hypotheses being tested. Evaluation of the general importance of fish-habitat interactions must await the application of common observationaland experimental methodologies to a wider range of fish taxa and locations. [ABSTRACT FROM AUTHOR]

Seagrass plays a major role in supporting the processes and functionof the marine environment and is a key fisheries habitat, which provides nursery, feeding and breeding areas for fish and crustaceans. Seagrass beds also stabilise the seabed, trap sediments, reduce coastalerosion and provide the basis for the food chain through photosynthesis. The goal of this project is to establish a seagrass-fish habitatspatial model that will quantitatively assess the economic value of seagrass habitats, particularly for fisheries production and this paper describes a preliminary step in the model construction. With the help of fisheries scientists from the South Australian Research and Development Institute (SARDI), the functional relationship of some economically important species of fish, crustaceans and molluscs to seagrass habitats was investigated. As a result, a seagrass residency index (SRI) fior some species has been estimated indicating the species most likely to be affected by changes in health and abundance of the seagrass beds in the coastal waters of South Australia. The information collected mainly relates to the periods of time spent amongst seagrass beds, sheltered reefs and open waters at different life stages ofthe fish: larval/juvenile, adult/feeding and adult/spawning. It was then hypothesized that the SRI would be a weighted sum of the averages of the estimated residence time at each stage. This paper describeshow the SRI figures were calculated and outlines the intended use ofthe indices, in conjunction with other information, to assess the value of seagrass habitats. [ABSTRACT FROM AUTHOR]