Despite repeated calls to action, proposals for urban conservation are often met with surprise or scepticism. There remains a pervasive narrative in policy, practice, and the public psyche that urban environments, although useful for engaging people with nature or providing ecosystem services, are of little conservation value. We argue that the tendency to overlook the conservation value of urban environments stems from misconceptions about the ability of native species to persist within cities and towns and that this, in turn, hinders effective conservation action. However, recent scientific evidence shows that these assumptions do not always hold. Although it is generally true that increasing the size, quality, and connectivity of habitat patches will improve the probability that a species can persist, the inverse is not that small, degraded, or fragmented habitats found in urban environments are worthless. In light of these findings we propose updated messages that guide and inspire researchers, practitioners, and decision makers to undertake conservation action in urban environments: consider small spaces, recognize unconventional habitats, test creative solutions, and use science to minimize the impacts of future urban development.

We provide the first in situ measurements of antenna element (tile) beam shapes of the Murchison Widefield Array (MWA), a low radio-frequency interferometer and an SKA * precursor. Most current MWA processing pipelines use an assumed beam shape, errors in which can cause absolute and relative flux density errors, as well as polarisation 'leakage'. This makes understanding the primary beam of paramount importance, especially for sensitive experiments such as a measurement of the 21 cm line from the epoch of reionisation (EoR). The calibration requirements for measuring the EoR 21 cm line are so extreme that tile to tile beam variations may affect our ability to make a detection. Measuring the primary beam shape from visibilities alone is challenging, as multiple instrumental, atmospheric, and astrophysical factors contribute to uncertainties in the data. Building on the methods of Neben et al. (2015), we tap directly into the receiving elements of the MWA before any digitisation or correlation of the signal. Using ORBCOMM satellite passes we are able to produce all-sky maps for 4 separate tiles in the XX polarisation. We find good agreement with the cutting-edge 'fully' embedded element (FEE) model of Sokolowski et al. (2017), and observe that the MWA beamformers consistently recreate beam shapes to within ∼ 1dB in the reliable areas of our beam maps. We also clearly observe the effects of a missing dipole from a tile in one of our beam maps, and show that the FEE model is able to reproduce this modified beam shape. We end by motivating and outlining additional onsite experiments to further constrain the primary beam behaviour.beam, which has a full-width half-maximum of ∼ 25 • at 150 MHz (Tingay et al. 2013). The regular spacing of the dipoles means that the quantised beamformer delays are exactly correct for a set of pointings, reducing the complexity of the instrument. By using identical receiving elements, a number of computational simplifications can be made to calibration and imaging, as beam corrections can be made in image space, avoiding costly convolutions in visibility space.Many calibration schemes make assumptions on beams/receiving elements (e.g. Kazemi et al. 2013;Tasse et al. 2013), and others explicitly use the beam 1 arXiv:1808.04516v1 [astro-ph.IM]

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Prey species may display anti‐predatory behavior, i.e., flight, increased vigilance, and decreased feeding, in response to the true presence of a predator or to the implied presence of a predator through, e.g., acoustic cues. In this study, we investigated the anti‐predatory reactions of moose ( Alces alces ) to acoustic stimuli related to hunting, at saltlick stones, a known attractant. In before‐during‐after‐control‐impact experiments, we compared the behavioral responses of individuals to: (i) two hunting‐related acoustic stimuli—hunting dog barking and human speaking; (ii) nonpredatory acoustic stimuli—bird sounds and; and (iii) no acoustic stimulus (control). We asked: (1) How does the probability of moose leaving the site differ depending on the stimulus they are exposed to?; (2) What affect do the acoustic stimuli have on the amount of time moose spend vigilant, feeding, or away from the site?; and (3) What affect do the stimuli have on the time between events at a site? We found that when exposed to the human stimulus, moose left the sites in 75% of the events, which was significantly more often compared to the dog (39%), bird (24%), or silent (11%) events. If moose did not leave the site, they spent more time vigilant, and less time feeding, particularly when exposed to a dog or human stimulus. Furthermore, moose spent the most time away from the site and took the longest to visit the site again after a human stimulus. Moose were also more likely to leave the site when exposed to the bird stimulus than during silent controls. Those that remained spent more time vigilant, but their behaviors returned to baseline after the bird stimulus ended. These findings suggest that acoustic stimuli can be used to modify the behavior of moose; however, reactions towards presumably threatening and nonthreatening stimuli were not as distinct as we had expected.

Roads and traffic may be contributing to global declines of insect populations. The ecological effects of roads often extend far into the surrounding habitat, over a distance known as the road‐effect zone. The quality of habitat in the road‐effect zone is generally degraded (e.g., due to edge effects, noise, light, and chemical pollution) and can be reflected in species presence, abundance, or demographic parameters. Road‐effect zones have been quantified for some vertebrate species but are yet to be quantified for insects. Investigating the road‐effect zone for insects will provide a better understanding of how roads impact ecosystems, which is particularly important given the role insects play as pollinators, predators, and prey for other species. We quantified the road‐effect zone for nocturnal flying insects along three major freeways in agricultural landscapes in southeast Australia. We collected insects using light traps at six points along 2‐km transects perpendicular to each highway (n = 17). We sorted the samples into order, and dried and weighed each order to obtain a measure of dry biomass. Using regression models within a Bayesian framework of inference, we estimated the change in biomass of each order with distance from the road, while accounting for environmental variables such as temperature, moon phase, and vegetation structure. The biomass of nine of the ten orders sampled did not change with distance from the freeway. Orthoptera (i.e., grasshoppers and crickets) was the only order whose biomass increased with distance from the freeway. From our findings, we suggest that the impacts of roads on insects are unlikely extending into the surrounding landscape over a distance of 2 km. Therefore, if there are impacts of roads on insects, these are more likely to be concentrated at the road itself, or on finer taxonomic scales such as family or genus level.

Carrion of wild ungulates is an important resource for microbes, invertebrates and vertebrates, and affects local plant communities and soils. Most wild ungulates in central Europe, however, are intensely hunted and removed from the ecosystem, thus not available as carrion. This study explores the use of evisceration residues as a resource by necrophagous insects in a temperate mountainous forest in Germany. We experimentally compared the relative abundance of necrophagous insects between sites of caged roe deer carcasses and evisceration residues of roe deer using pitfall‐traps. While evisceration residues were used by necrophagous insects, significantly more individuals were sampled at entire deer carcasses; when corrected for biomass, however, no significant difference in abundance for Coleoptera groups was found. Overall, evisceration residues were used earlier and for a shorter period than entire deer carcasses. Leaving evisceration residues on site where game animals are obtained might help maintain specialized necrophagous insect communities, although their ecological role cannot completely replace that of whole carcasses of wild ruminants.

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