975 resultados para breeding season


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Spatial and temporal variation in the breeding of Masked Lapwings (Vanellus miles) in Australia were examined using data from Birds Australia’s Nest Record Scheme (NRS; 1957–2002), the Atlas of Australian Birds (1998–2006), and climatic data (1952–2006). Breeding in north-western Australia was concentrated in summer, while in other regions the peak of breeding occurred during spring. Breeding success varied between regions and years but was generally highest in Tasmania. Clutch-size (mean 3.57 eggs ± 0.033 s.e., n = 549 clutches) did not vary regionally or temporally. In the north-east, breeding became earlier over time (~1.9 days per year, NRS), while in the south-east, breeding became later (~0.9 days per year); in other regions temporal trends were not evident. Only Tasmania showed a significant temporal change in breeding success (decrease of ~1.5% per year). All regions experienced warming climates, and annual rainfall increased in north-western regions and decreased in eastern regions. There were weak or no relationships between the amount or success of breeding, clutch-size and the climatic variables considered (with the possible exception of Tasmania), suggesting either that data limitations precluded us from detecting subtle effects or that Masked Lapwings have been little influenced or are resilient to changes in climate over most of their range.

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Urban expansion is a principal process threatening biodiversity globally. It is predicted that over half of the world's population will reside in urban centres by 2010. If we are to conserve biodiversity, a shift in perspective from traditional ecological studies based in natural environments, to studies based in less natural environments is paramount. To effectively conserve species which occur in urban environments, comprehensive analysis is necessary to determine the processes that are driving this urban usage. Geographical Information Systems (GIS) technology provides a valuable tool for efficient spatial analysis and predictive mapping of species distributions.

This study used GIS to analyze current breeding sites for the powerful owl, a vulnerable top order predator in urban Melbourne, Australia. GIS analysis suggests that a number of ecological attributes were influencing powerful owl usage of urban environments. Using these ecological attributes, predictive mapping was undertaken, which identified a number of potential breeding sites for powerful owls within urbanized Melbourne.

Urban environments are traditionally perceived as “the wastelands” of natural environments, however, this study demonstrates that they have the potential to support apex predators, an important finding for the management of rare and threatened species.

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Given the importance of season ticket holders (STH) to sporting organisations, we empirically examine a scale for measuring their attitudes to the season ticket product. This involved identifying through qualitative research and past literature, the various elements that are perceived to comprise the season ticket package and developing items to measure STH attitudes to them. The season ticket package was decomposed into six key components, closely mirroring past research. A survey of over 2,500 STH of a professional sporting organisation was then conducted, incorporating items related to these six areas, overall satisfaction and disconfirmation of expectations. The results of Exploratory Factor Analysis on those items is presented here, with results suggesting the items are valid measures of season ticket holder attitudes that capture the breadth of the STH experience.

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Although it seems counter-intuitive, past studies have found that the attitudes to the on-field performance of a team have only a small direct impact on the overall satisfaction of members (season ticket holders). By managing other aspects of the package well (e.g., ticketing, customer service, communications), membership can satisfy even when the on-field results do not. In this research, we examine whether on-field performance, measured both objectively and subjectively, has an indirect "halo" effect on attitudes towards those other aspects of the membership offering. An examination of data collected through 63 member satisfaction surveys of 14 different AFL clubs in the period 2003 - 2007 suggests that, predictably, a change to the win-loss ratio has a strong impact on attitudes to on-field performance and overall satisfaction. However, changes in on-field performance are also significantly correlated with changes in attitudes to areas like the extent to which one feels personally involved with the club and the administration of the club. The data allows the determination of the extent ofthis halo effect where a change in on-field performance (win percentage) has a predictable impact on attitudes to other aspects of the clubs activities, allowing club management to benchmark their performance in these areas even when on-field results fluctuate year to year.

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The Australian endemic brown songlark, Cinclorhamphus cruralis, is one of the most sexually size-dimorphic of all birds, and yet its breeding ecology remains poorly documented. Here we redress this situation by describing the breeding activities of brown songlarks over three years (1998–2000) in the semi-arid grasslands of south-western New South Wales. Study populations of this nomadic species were selected in late August of each year on the basis of high adult abundance. Adult males at these sites were, on average, 2.3 times heavier than females. Over the three seasons, nesting activities started in early to late August and continued until early November or December. Males were highly polygynous and, on average, occupied territories of about 4.0 ha. Nests were well concealed at the base of small shrubs and grass tussocks or in thick herbage. Clutches ranged in size from 2 to 5 eggs (mean 3.2) and were incubated exclusively by the female for 11–13 days (mean 12.1). Nestlings received a range of invertebrate prey, mainly from the female, for 10–14 days (mean 11.5) before leaving the nest. Only 17% of nesting attempts were estimated to be successful, and each of these nests produced an average of 2.7 fledglings. Predators, including foxes, Vulpes vulpes, and brown snakes, Pseudonaja textilis, were the main cause of nest failure. Some females produced replacement clutches following nest failure, while others laid second clutches after the success of an earlier brood. We speculate that extreme size dimorphism has evolved in this species because (i) males compete physically for breeding territories, and (ii) habitat heterogeneity and excellent visibility of their surroundings allow some males to defend territories of sufficient size to support nesting by multiple females

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The New Holland Mouse is critically endangered within Victoria. A decline in the species abundance resulted from below average rainfall and structural changes to habitat vegetation. A captive breeding program was established as part of the species recovery plan. Induced breeding throughout the year, under controlled conditions, was limited by the species aggressive behaviour.

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¯Large interannual variations in reproductive success caused by fluctuations in oceanography and prey availability are common to many species of air breathing epipelagic predators. In contrast, little is known about variation in benthic foragers such as Australian fur seals (Arctocephalus pusillus doriferus). Between 1997 and 2007, pup production was assessed in 9 yr, while the timing of breeding and adult female condition was assessed in 5 yr at Kanowna Island in Bass Strait, southeastern Australia. Pup production was variable ( ¯x = 1,726 ± 42, range = 1,386–2,301), but without temporal trend, as was median birth date ( ¯x = 23 November±1, range = 21–25 November) and pupping synchrony (period of 90% births: ¯x = 28 ± 2 d, range = 23–31 d). Pup production was negatively correlated with median birth date and positively correlatedwith female condition,winter sea-surface temperature (SST) and zonal wind strength within Bass Strait. Pup production was also negatively correlated with SST in the previous summer within Bass Strait and in the eastern Great Australian Bight upwelling region. The results suggest that the reproductive success of Australian fur seals is influenced by oceanography but less so than in otariids foraging epipelagically in major upwellings. Despite spanning several El Niño events, no correlation between pup production and the Southern Oscillation Index was observed.

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The Powerful Owl is an elusive species inhabiting the forests of mainland eastern Australia. Obtaining crucial information on aspects of their breeding behaviour and dispersal has proven extremely difficult, even though other aspects of their ecology are well studied. Here we use molecular methods to investigate the breeding behaviour and dispersal of the Powerful Owl in two different habitats: highly fragmented forest along the urban fringe and continuous forest.DNA profiles of Powerful Owls were obtained predominately from shed feathers collected opportunistically between 1995 and 2006. Seven breeding pairs of Powerful Owls were identified, from which shed feathers were collected during 2003, 2004 and 2005. By comparing DNA profiles, one pair of Owls was found to have occupied the same breeding site for 10 years (1995–2005). The dispersal or movements of five offspring from this pair was also determined to be either of two scenarios: (1) the juvenile moves from the natal territory; however, isn’t breeding; and (2) the juvenile is recovered as part of a breeding pair. Two pairs of Owls breeding in the urban fringe habitat were closely related, but no incidences of extra-pair fertilisation were detected among pairs in either habitat. This study provides new information about the breeding behaviour and dispersal of the Powerful Owl, and shows the potential of using genetic data sourced from shed feathers for studying cryptic, rare or elusive species.

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Season ticket holders (STHs) are vital to professional sport club revenue and are purported to be the most loyal and involved of fans. Nonrenewal (churn) rates among STHs, however, often exceed 20%. Low member satisfaction, poor onfield performance and low game attendance have all been posited as explanations of high churn rates, but rarely empirically examined. The research reported here employed a unique study of over 4,500 STHs, incorporating both survey research and measures of actual behavior, to determine which variables best explain and predict churn within two professional sport teams. A variety of analytical techniques all suggest that the key variables predicting churn are length of relationship and the number of games attended. New, low attending STHs are over five times more likely to churn than long-term, frequent attendees. Typical management practice is to run reward schemes designed to increase attendance and encourage renewal. The results of this study suggest that fundamental differences in the way new, low attending members evaluate the season ticket product may render those schemes ineffective. Shifting the focus of these STHs toward the intangibles of the product, such as stronger feelings of involvement, a sense of community and increased patron worth, could be more effective at reducing churn.