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Kutt, A.

Publications and source records attributed to Kutt, A..

4 recordsLinked to original sources

The pattern of mammal change in Garig Gunak Barlu (Cobourg) National Park suggests a fire-mediated pathway to decline and one for recovery

ContextFire is a key driver of wildlife pattern in northern Australia, and in recent decades there has been concerted efforts to return burning practices from unmanaged wildfire to approaches more in tune with traditional approaches to fire management undertaken by First Nations people. AimsWe examined fire pattern (early and late dry season) and distance from coast in relation to mammal pattern on a Cobourg peninsula, as there was some evidence in variable patterns in fire history and mammal persistence in this landscape. MethodsIn this study we examined data collected from Garig Gunak Barlu (Cobourg) National Park, Northern Territory, between 2004 and 2017. We investigated the relationship between all native mammal abundance and species richness, and abundance for eight species, with the three environmental variables (distance from coast, preceding early dry and late dry season burning frequency), using an information theoretic model selection and averaging framework. Key resultsThere is a distinctive change in the fire and mammal pattern with respect to distance from the coast; that is, early and late dry season burning increasing moving inland from the coast, and a concomitant decrease or persistence in some key species on this fire gradient. ConclusionsOur results suggest that fire management in northern Australia still needs targeted research linked to active management to more effectively prevent declines of mammal populations. ImplicationsThe location and shape of Garig Gunak Barlu (Cobourg) National Park provide an excellent opportunity to undertake some natural experiments in strategic burning to investigate improved approaches to conservation in fire-prone landscapes.

ecology↗

Monitoring data indicates some annual change in the mammal fauna at Nitmiluk National Park between 2005 and 2018 but a reduction in effort confounds any interpretation

ContextThe decline, extirpation and extinction of Australias mammal fauna is without peer. In recent decades long term monitoring has revealed tragic patterns in iconic locations such as Kakadu National Park. AimsPast studies have described universal patterns across multiple national parks in the Northern Territory, linking the declines to fire management; however, much of the data in Nitmiluk National Park do not cover the period that encompasses this decline. We examine this data separately to look for patterns with respect to fire history. MethodsWe examined standardised mammal survey data collected in Nitmiluk from 2005 to 2018, to look for correlates with year of survey, time since last burnt, and the frequency of early season and late season burns. Key resultsDespite subtle difference in methods over the years, we found there were some annual changes in the mammals, but little discernible pattern of change correlated to fire regime (which itself indicated an improvement in seasonality, and the extent of burning overall over this period). Instead, there was a distinct reduction in the survey effort. ConclusionsOur study provides further support for the pitfalls of ecological monitoring losing focus, being decoupled from management actions, and allowing ill-conceived changes in design. We recommend that future monitoring at Nitmiluk should focus on key management questions (i.e., fire), best methods for target taxa (i.e. camera traps), more regular and flexible sampling linked to a conceptual model, and integration and co-design with the local land managers, rangers and Traditional Owners. Short SummaryRe-examination of the mammal data collected in monitoring sites at Nitmiluk National Park between 2005 to 2018 indicated little pattern with fire regime over time, and instead indicated that a reduction in effort, had reduced the ability to find pattern With sparse and declining mammal population in northern Australia, future monitoring needs to be focused on key management questions.

ecology↗

Indistinct changes in the mammal fauna between 1986-2017 at Judbarra-Gregory National Park, Northern Territory

The mammal fauna in many parts of northern Australia has undergone dramatic changes in the past 20-30 years, though longitudinal data that spans this period are limited and largely from coastal and high rainfall regions. We examined data from Judbarra-Gregory National Park that has been collected in a systematic manner (once in 1986 and then 2005-2017), including two years where camera trapping was included (2015 and 2017). We standardised this data in a simple manner (i.e., species by relative abundance and site frequency) to examine if there were any stark changes over this time span. We also undertook some simple modelling of mammal pattern with respect to fire and fractional green and bare cover metrics. Though we recognise some limitations in our comparisons (i.e., spatial variation in sites and methods), the data indicated that the mammal fauna had generally not changed substantially in composition, relative abundance or frequency across sites. There were meaningful models correlating mammal pattern to fire frequency, time since fire, fraction green and bare parameters. However, some species symptomatic of small mammal decline elsewhere (i.e., Rattus tunneyi) may have become less common, whereas other species were recorded for the first time in more recent years (2010-2017), particularly by camera traps (i.e., Trichosurus vulpecula, Isoodon macrourus, Melomys burtoni). We postulate that change in the mammal fauna on the semi-arid fringe of tropical savannas may have occurred prior to the 1980s, with a long history of cattle grazing a possible contributing factor. The mammal fauna there, is also perhaps naturally sparse and heterogeneous in spatial and temporal distribution.

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↗