Powerful owls : possum assassins move into town
- Authors: Cooke, Raylene , Hogan, Fiona , Isaac, Bronwyn , Weaving, Marian , White, John
- Date: 2018
- Type: Text , Book chapter
- Relation: Urban Raptors: Ecology and Conservation of Birds of Prey in Cities Chapter 11 p. 152-165
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- Reviewed:
- Description: Once thought to live only in large forested areas, the powerful owl (Ninox strenua), Australia’s largest and most iconic of owls (figure 11.1), surprisingly is now turning up frequently in the cities of eastern Australia. Powerful owls require ample prey and large tree cavities for nest sites how this top-order predator is able to survive in human-dominated landscapes is an important question for conservation and the focus of ongoing research. The powerful owl is endemic to Australia, resident in the three eastern mainland states and the Australian Capital Territory, and classified nationally as “rare.”2,3 First described by Gould in 1838, powerful owls are an unusual raptor in that they do not exhibit reversed sexual size dimorphism, the prevalent trait among raptors in which females are larger than males. For reasons still not understood, male powerful owls grow to a height of 65 cm and weigh up to 1,700 g, compared to females, which grow to a height of 54 cm and weigh up to 1,308 g.1
Urbanization and raptors : trends and research approaches
- Authors: Cooke, Raylene , Hogan, Fiona , Isaac, Bronwyn , Weaving, Marian , White, John
- Date: 2018
- Type: Text , Book chapter
- Relation: Urban raptors: ecology and conservation of birds of prey in cities p. 64-75
- Full Text: false
- Reviewed:
- Description: Urbanization presents a major global issue for the conservation and survival of many different species. With the increasing footprint of cities and intensification of our use of urban areas, wildlife faces extremely difficult challenges to live there. Understanding how species respond to urban processes and how to design urban landscapes that facilitate species’ presences are major emerging research and management priorities. Despite general negative responses to increasing urbanization, some animal taxa, both native and introduced, appear to benefit from urban environments by capitalizing on novel environments and abundant resources.1 Those that are common in urban systems display particular physical characteristics and ecological traits.2,3,4 They also frequently display a level of behavioral plasticity or tolerance, adjusting their behavior to interact with, and survive in, urban environments.5,6 Termed urban-adaptors,7 these species may exhibit altered spatial,8,9,10 foraging,11,12 and breeding behaviors,13 as detailed in chapter 2.
Surviving urbanisation : Maintaining bird species diversity in urban Melbourne
- Authors: White, John , Fitzsimons, James , Palmer, Grant , Antos, Mark
- Date: 2009
- Type: Text , Journal article
- Relation: Victorian Naturalist Vol. 126, no. 3 (2009), p. 73-78
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- Reviewed:
- Description: The relationships between vegetation and bird communities within an urban landscape are synthetised, based on a series of studies we conducted. Our studies indicate that streetscape vegetation plays an important role in influencing urban bird communities, with streetscapes dominated by native plants supporting communities with high native species richness and abundance, while exotic and newly-developed streetscapes support more introduced bird species and fewer native bird species. Native streetscapes can also provide important resources for certain groups of birds, such as nectarivores. Our research has also revealed that urban remnants are likely to support more native bird species if they are larger and if they contain components of riparian vegetation. Vegetation structure and quality does not appear to be as important a driver as remnant size in determining the richness of native bird communities. Introduced birds were shown to occur in remnants at low densities, irrespective of remnant size, when compared to densities found in streetscapes dominated by exotic vegetation. We discuss our results in terms of practical planning and management options to increase and maintain urban avian diversity and conclude by offering suggestions for future fields of research in terms of urban bird communities.
Determinants of native avian richness in suburban remnant vegetation : Implications for conservation planning
- Authors: Palmer, Grant , Fitzsimons, John , Antos, Mark , White, John
- Date: 2008
- Type: Text , Journal article
- Relation: Biological Conservation Vol. 141, no. 9 (2008), p. 2329-2341
- Full Text:
- Description: While urban areas are increasingly recognized as having potential value for biodiversity conservation, the relationship between biodiversity and the structure and configuration of the urban landscape is poorly understood. In this study we surveyed birds in 39 remnant patches of native vegetation of various sizes (range 1-107 ha) embedded in the suburban matrix in Melbourne, Australia. The total richness of species within remnants was strongly associated with the size of remnants. Remnant-reliant species displayed a much stronger response to remnant area than matrix-tolerant species indicating the importance of large remnants in maintaining representative bird assemblages. Large remnants are important for other ecological groups of species including migratory species, ground foraging birds and canopy foraging birds. Other landscape (e.g. amount of riparian vegetation) and structural components (e.g. shrub cover) of remnants have a lesser role in determining the richness of individual remnants. This research provides conservation managers and planners with a hierarchical process to reserve design and management in order to conserve the highest richness of native species within urban areas. First of all, conservation efforts should preferentially focus on the retention of larger remnants of native vegetation. Second, where possible, riparian vegetation should be included within reserves or, where it is already present, should be carefully managed to ensure its integrity. Third, efforts should be focused at maintaining appropriate habitat and vegetation structure and complexity. © 2008 Elsevier Ltd. All rights reserved.