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Reside, A. E.

Publications and source records attributed to Reside, A. E..

4 recordsLinked to original sources

Species richness and trait diversity show parallel island-biogeographic patterns across Australian islands

Island biogeography is the theoretical and empirically validated expectation that an islands biodiversity is ultimately limited by its size and isolation, with larger and less isolated (from mainland communities) islands supporting greater diversity. Island biogeography is generally applied to simple metrics of diversity such as species richness (number of different species); however, fewer studies have used traits to measure biodiversity. An organisms traits -- e.g., body mass, age at sexual maturity, trophic level -- can be used to measure biodiversity and understand how ecological communities function. We quantified species richness for birds, mammals, reptiles, and amphibians, and functional diversity for birds and mammals (for which sufficient trait data were available), and tested whether this diversity can be predicted using the theory of island biogeography. We identified 9,103 Australian islands, of which 1,661 had at least one (native and/or non-native) non-marine species present according to the Atlas of Living Australia. As expected, tetrapod species richness (S) increased with island area (A) (z = 0.299 {+/-} 0.012) following a typical power-law relationship (i.e., S = cAz, where z = 0.2-0.4), but was not predicted by distance from mainland -- consistent with the pattern observed on other recently (< 10,000 years) isolated continental islands. We found that trait richness increased at the same rate with island area as species richness for mammals, but for birds, trait richness increased more slowly than species richness. Trait turnover increased modestly with inter-island distance, whereas trait nestedness was unrelated to distance. Trait richness increased strongly with species richness in both birds and mammals, and island area and isolation explained no additional variation in functional richness after accounting for species richness. These results indicate that island geography influences functional diversity primarily through species accumulation, rather than through direct effects on occupied trait space. Overall, the trait space of smaller islands tended to be nested within that of larger, nearby islands; the main differences among similar-sized islands are due to turnover (change in species/trait combinations among assemblages), and the effects are more pronounced in mammals compared to birds. We also found evidence for an asymptotic relationship between trait and species turnover in both birds and mammals, suggesting close coupling between taxonomic and functional turnover, with some saturation of trait turnover at high species turnover. Large islands that are simultaneously more isolated might offer conservation advantages by reducing the influence of threatening processes on the mainland if distance limits access of people and invasive species.

ecology↗

A typology of Australian terrestrial bird communities

AimIncreasing interest in holistic measurement of the response of fauna communities to interventions requires suitable community condition metrics. However, the development of such metrics is hindered by the absence of broad-scale typologies at suitable spatial and ecological resolutions. We aimed to derive a preliminary typology of terrestrial bird communities for Australia, based on bird co-occurrence data, and describe and map the likely distribution of each community type across the continent. LocationMainland Australia, continental islands Time period1973-2022 Major taxa studiedAves MethodsWe used fine-scale co-occurrence data from standard 2-ha surveys in BirdLife Australias citizen-science database. After filtering to reduce bias, we used hierarchical clustering followed by iterative consultation with experts to identify reliably distinct and recognisable terrestrial bird communities across Australia. We used Maxent to model the likely distributions of each community, and developed community descriptions based on each communitys composition and distribution. ResultsThe resultant typology included 29 reliably distinct and recognisable bird communities with major clusters corresponding with seven broad geographical regions. The distributions of bird communities did not correspond tightly to the boundaries of major vegetation groups, with most communities occurring across multiple vegetation types. Main ConclusionsOur preliminary typology of bird communities provides a standard classification at a continental scale. It newly defines distinct bird communities as entities for which condition benchmarks can be established to allow assessment of their conservation status and monitoring of change over time. Refinement will enable cryptic communities in areas with sparse data to be identified. The method could be translated to other regions where adequate coverage of data in the form of standardised surveys of fauna are available. Vast biodiversity datasets delivered through citizen science programs provide the opportunity to develop such typologies for fauna communities, as a precursor to developing targeted and informative community condition metrics.

ecology↗

Limiting the loss of terrestrial ecosystems to safeguard nature for biodiversity and humanity

Humanity is on a pathway of unsustainable loss of the natural systems upon which we, and all life, rely. To date, global efforts to achieve internationally-agreed goals to reduce carbon emissions, halt biodiversity loss, and retain essential ecosystem services, have been poorly integrated. However, these different goals all rely on preserving natural ecosystems. Here, we show how to unify these goals by empirically deriving spatially-explicit, quantitative area-based targets for the retention of natural terrestrial ecosystems. We found that at least 67 million km2 of Earths natural terrestrial ecosystems (~79% of the area remaining) require retention - via a combination of strict protection but more prominently through sustainably managed land use regimes complemented by restoration actions - to contribute to biodiversity, climate, soil and freshwater objectives under four United Nations Resolutions. This equates to retaining natural ecosystems across ~50% of the total terrestrial (excluding Antarctica) surface of Earth. Our results show where retention efforts could be focussed to contribute to multiple goals simultaneously. The retention targets concept that we present explicitly recognises that such management can and should co-occur alongside and be driven by the people who live in and rely on places where natural and semi-natural ecosystems remain on Earth.

ecology↗

Conservation attention necessary across at least 44% of Earth’s terrestrial area to safeguard biodiversity

More ambitious conservation efforts are needed to stop the global biodiversity crisis. Here, we estimate the minimum land area to secure important sites for terrestrial fauna, ecologically intact areas, and the optimal locations for representation of species ranges and ecoregions. We discover that at least 64 million km2 (44% of terrestrial area) requires conservation attention. Over 1.8 billion people live on these lands so responses that promote agency, self-determination, equity, and sustainable management for safeguarding biodiversity are essential. Spatially explicit land-use scenarios suggest that 1.3 million km2 of land requiring conservation could be lost to intensive human land-uses by 2030, which requires immediate attention. However, there is a seven-fold difference between the amount of habitat converted under optimistic and pessimistic scenarios, highlighting an opportunity to avert this crisis. Appropriate targets in the post-2020 Global Biodiversity Framework to ensure conservation of the identified land would contribute substantially to safeguarding biodiversity.

ecology↗