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Experimental approaches to measure territory defence can be used to interpret the relative magnitude of intraspecific aggression in different ecological contexts. The aim of this study is to examine the response of Fijian forest bird species to conspecific intruders using playback of previously recorded songs along an elevational gradient. We address two questions: Do different foraging guilds in Fiji's forest birds show different patterns of territorial defence behaviour towards conspecific intruders? Secondly, do Fiji's forest birds show stronger territorial defence at higher elevations? We explore these questions across two foraging guilds (insectivore and omnivore) on Viti Levu Island, Fiji. All four focal species had a stronger response at the highest elevation, and the endemic insectivore had the strongest response. Perhaps high elevation insects are less abundant and hence increased aggressiveness is favoured to defend the territory, and/or perhaps in general more aggressive birds colonise higher elevation areas, both ideas that require further testing. This study provides first insights into response to conspecifics in Fiji's forest birds that can be explored in relation to avian behaviour also in the context of human activity, human disturbance and threats to the persistence of birds across elevational gradients. [ABSTRACT FROM AUTHOR]

Half of Fiji's 66 land bird species are endemic and 15 species are threatened with extinction following ~70% deforestation. Under conditions of large-scale habitat loss, secondary vegetation can be important for woodland biodiversity conservation. This study compares avian abundance and diversity in secondary vegetation on Viti Levu, Fiji. We use avian point surveys at replicate sites in regenerating mahogany plantation (Colo-i-Suva; eastern lowlands), regenerating native forest (Koroyanitu National Heritage Park; western highlands) and grassland (Koroyanitu National Heritage Park). We ask if there are differences in avian abundance and species richness across habitat types. In total, we recorded 1063 birds from 33 bird species. Regenerating forest sites had the greatest species richness with mostly endemic and native woodland bird species and few introduced species. Regenerating plantation sites harboured a comparable number of endemic species and threatened species as regenerating forest sites but had significantly fewer native species and no introduced species. We recorded the most birds at grassland sites as well as the most introduced species. The findings of this study underscore the importance of regenerating native forest and regenerating plantation as habitats for Fiji's endemic woodland birds. Increasing the expanse of regenerating forest sites should be considered for conservation planning to sustain Fiji's extant birds. [ABSTRACT FROM AUTHOR]

Species composition and life history traits of trees in native forests in the dry zone of Fiji were investigated. Areas receiving less than 2500 mm yr-1 of rain and covered with native forest were identified using maps, aerial photographs, estimated climate (WorldClim), and field reconaissance. Ten forest remnants were identified and species lists and data on natural history and disturbance were compiled. Cluster analysis and DECORANA identified two principal forest types, moist forest (MF) and tropical dry forest (TDF), each defined by unique climate, species composition, and tree life history characteristics. TDF (reported for the first time from Fiji) has a pronounced dry season (5 consecutive months with <100 mm rainfall each) and several deciduous canopy species. MF lacks a pronounced dry season and has few deciduous species. The amount and variability of rainfall seem to influence the type of forest in a particular location and disturbance is negatively correlated with precipitation. TDF are probably Fiji's most endangered ecosystems. [ABSTRACT FROM AUTHOR]

The flora and vegetation of an area in north-eastern Vanua Levu that is part of Fiji's last major system of mesic forest were studied and revealed a mosaic of vegetation types, including mesic sclerophyll forest, transition forest, stunted Dacrydium nidulum forest, mangrove forest, montane forest, brackish and freshwater wetlands, and disturbed landscapes. This is much more diverse than indicated by the previous "dry forest" label. The flora comprises more than 268 native species, several of which are rare or narrowly distributed. Relatively large and undisturbed stretches of vegetation and the presence of rare and novel species and vegetation types suggest that the landowners should be given every possible assistance in protecting this unique landscape. [ABSTRACT FROM AUTHOR]