57 resultados para Photografic Club of Mexico


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The bryophyte floristics of industrial/commercial streetscapes of urban Victoria and the importance of various substrata to species richness were explored. Species richness was low compared to healthy natural environments. Thirty mosses from 14 families, and six liverworts, each from different families, were identified. Most species occurred at fewer than 30% of sites, showing the patchy nature of their distribution. Only three species occurred at more than half the sites. Markedly higher species richness occurred on soil than on any other substratum. Epiphytes were extremely few. The low bryodiversity of streetscapes, the patchy nature of the bryophytes and the high number of colonists suggest that the streetscapes have not fulfilled their potential in providing connectivity between urban and non-urban areas. Colonists characteristically occur early in the successional sequence of disturbed areas but, as streetscapes are continually disturbed, colonists effectively are climax species for this habitat. Better management of streetscapes to provide more complex habitat is needed to enable colonisation of these areas by bryophyte species that are more representative of our ever-shrinking natural habitats.

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The Masked Lapwing Vanellus miles is a common ground-nesting shorebird inhabiting grasslands, paddocks, rivers, lakes, swamps and, tidal mud flats. It is particularly common in the urban areas of Phillip Island, Victoria (Dann 1981, Marchant and Higgins 1993). The Masked Lapwing usually lays between one and four eggs (the mean number of eggs per clutch of this study was 3.6 ± 1 SD) that hatch after 31 days. Both sexes incubate eggs, brood young and defend the eggs and young. Masked Lapwings produce precocial and nidifugous chicks that remain with the adults on defended territories until fledging (Marchant and Higgins 1993, Thomas 1969). The chicks are able to feed themselves within hours of hatching and rely on their parents only for protection (alarm signals) and warmth (brooding) (Marchant and Higgins 1993). Here we report three instances of likely co-operative breeding of Vanellus miles on Phillip Island between 18 July and 13 September 2012.

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Jumping spiders belonging to the endemic Australian genus Maratus are popularly referred to as peacock spiders, so called for the remarkable courtship displays of the often brightly coloured males. Several Maratus splendens were found in Buldah State Forest, East Gippsland in 2011 and 2013, representing the first records of this species from Victoria. Until recently, this species was known only from around Sydney. While a degree of caution should be exercised whenever implying possible new distributional records based on single localities, it is considered most likely that this discovery represents a genuine expansion in the known range of Maratus splendens. Details are also provided for a previously unpublished record from the central coast of New South Wales.

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 Some ground-nesting birds adopt a mixed strategy of nesting in the open, or under cover (e.g. vegetation). This may represent a trade-off between thermally favourable nest sites (covered) and those that enable the early detection and avoidance of predators (open). This study examined whether such a trade-off exists for Redcapped Plover Charadrius ruficapillus, whose eggs are preyed upon principally by Little Raven Corvus mellori. For real and artificial nests, nest temperatures under cover (real, 25.9 ± 0.1°C; false, 16.2 ± 0.5°C) were cooler than those in the open (real, 26.8 ± 0.1°C; false, 17.4 ± 0.9°C). Covered nests had more visual obstructions than open nests (covered, 65.5% ± 11.4%; open, 7.4% ± 2.8%) and a standardised measure of incubator escape distance, initiated by experimental human approaches, indicated incubators fled open nests at longer distances than for covered nests. Nests under cover showed a slightly (non-significant) higher probability of surviving one day (Daily Survival Rate [DSR] = 0.978) than those in the open (DSR = 0.950). For false nests containing model eggs, covered nests exhibited better survival to 10 days compared with open nests (20.4% vs. 4.7%). Thus, covered nests are associated with enhanced thermal environments and egg survival, but predators can approach the incubator more closely. Overall, the proposed trade-off between thermal and predation risks associated with nest sites appears to exist and explains the ongoing occurrence of nests in open and covered locations.

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We tested the 'cars cause less disturbance' hypothesis by comparing the flight-initiation distance (FID) evoked by a car versus a single walker for 38 species of waterbird (n = 657 standardised approaches). For the 15 species where we had sample size adequate for statistical testing (n ≥ 5), we found that cars elicited shorter responses after controlling for starting distance. Within-species analyses revealed that this difference was significant in 8 of 15 species. Although mean FIDs for car approaches were always shorter than FIDs toward single walkers in the remaining species (7), the tests in those species lacked sufficient power to draw meaningful conclusions. Our results provide support for the hypothesis that birds respond to cars at shorter distances. The wide taxonomic breadth of species investigated suggests that this principle may be broadly applicable, at least in waterbirds. The results of this study and the FID estimates we present will allow development of meaningful stimulus-specific buffer zones to protect waterbirds from disturbance.

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Round-leaf Pomaderris Pomaderris vacciniifolia F. Muell. ex Reissek (Rhamnaceae) is a Victorian endemic shrub listed as threatened under the Flora and Fauna Guarantee Act 1988 and critically endangeredunder the Environment Protection and Biodiversity Conservation Act 1999. A review of the available literature for P. vacciniifolia indicated most information is anecdotal or found in unpublished works. Better understanding of the ecology of P. vacciniifolia may help explain why it is vulnerable, and enhance future management. Future research should focus towards better understanding of P. vacciniifolia habitat, reproductive ecology, seed dispersal mechanisms and competitive ability and how these compare with more common sympatric congeners, to determine whether any differences could explain the relative success of these species. Targeted searches for this species on public and private land are warranted to reveal additional populations and fully appreciate the distribution of this species. (The Victorian Naturalist 131 (2) 2014, 44-51).

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This paper studied sales of BP branded gasoline in the United States of America prior, during and after the 2010 BP Deepwater Horizon oil spill accident. The research was funded by the Centre for Sustainable and Responsible Organisations at Deakin University. In what is perhaps the first behavioral study of consumer boycott using market level data, we found that consumers’ with geographic proximity to the accident were more likely to boycott the BP brand. In States that bordered or were close to the Gulf of Mexico, BP sales experienced a small but significant decline as compared to sales in States farther away. The small effect is surprising. We suspect this may be related to the inelastic nature of the product category and the high degree of product homogeneity within the category. It appears that consumers’ and the media’s vocalized outrage over the Deepwater Horizon accident did not result in significant changes in purchase behavior. As such, while consumers were outraged by BP’s actions, they continued to purchase the BP brand. Consumers who lived farther from the spill did not appear to alter their buying patterns even in the short-term, despite being exposed to similar media coverage and high levels of negative public sentiment. In examining changes in BP brand-share with both positive (i.e., claims of success in dealing with the spill) and negative events (evidence that attempts to stop the spill failed), we observed some associations between these events and changes in buying behavior. In States close to the accident, BP purchases increased with good news, market share declined with bad news. No apparent correlation was seen in States that were farther from the accident.

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Human-induced changes to habitats can have deleterious effects on many species that occupy them. However, some species can adapt and even benefit from such modifications. Artificial reefs have long been used to provide habitat for invertebrate communities and promote local fish populations. With the increasing demand for energy resources within ocean systems, there has been an expansion of infrastructure in near-shore benthic environments which function as de facto artificial reefs. Little is known of their use by marine mammals. In this study, the influence of anthropogenic sea floor structures (pipelines, cable routes, wells and shipwrecks) on the foraging locations of 36 adult female Australian fur seals (Arctocephalus pusillus doriferus) was investigated. For 9 (25%) of the individuals, distance to anthropogenic sea floor structures was the most important factor in determining the location of intensive foraging activity. Whereas the influence of anthropogenic sea floor structures on foraging locations was not related to age and mass, it was positively related to flipper length/standard length (a factor which can affect manoeuvrability). A total of 26 (72%) individuals tracked with GPS were recorded spending time in the vicinity of structures (from <1% to >75% of the foraging trip duration) with pipelines and cable routes being the most frequented. No relationships were found between the amount of time spent frequenting anthropogenic structures and individual characteristics. More than a third (35%) of animals foraging near anthropogenic sea floor structures visited more than one type of structure. These results further highlight potentially beneficial ecological outcomes of marine industrial development.