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1.
Animals (Basel) ; 13(17)2023 Aug 30.
Article in English | MEDLINE | ID: mdl-37685026

ABSTRACT

Conservation translocations have become increasingly popular for 'rewilding' areas that have lost their native fauna. These multispecies translocations are complex and need to consider the requirements of each individual species as well as the influence of likely interactions among them. The Dirk Hartog Island National Park Ecological Restoration Project, Return to 1616, aspires to restore ecological function to Western Australia's largest island. Since 2012, pest animals have been eradicated, and conservation translocations of seven fauna species have been undertaken, with a further six planned. Here, we present a synthesis of the innovative approaches undertaken in restoring the former faunal assemblage of Dirk Hartog Island and the key learnings gathered as the project has progressed.

2.
Conserv Biol ; 37(1): e13989, 2023 02.
Article in English | MEDLINE | ID: mdl-35979681

ABSTRACT

Landscape-scale conservation that considers metapopulation dynamics will be essential for preventing declines of species facing multiple threats to their survival. Toward this end, we developed a novel approach that combines occurrence records, spatial-environmental data, and genetic information to model habitat, connectivity, and patterns of genetic structure and link spatial attributes to underlying ecological mechanisms. Using the threatened northern quoll (Dasyurus hallucatus) as a case study, we applied this approach to address the need for conservation decision-making tools that promote resilient metapopulations of this threatened species in the Pilbara, Western Australia, a multiuse landscape that is a hotspot for biodiversity and mining. Habitat and connectivity were predicted by different landscape characteristics. Whereas habitat suitability was overwhelmingly driven by terrain ruggedness, dispersal was facilitated by proximity to watercourses. Although there is limited evidence for major physical barriers in the Pilbara, areas with high silt and clay content (i.e., alluvial and hardpan plains) showed high resistance to dispersal. Climate subtlety shaped distributions and patterns of genetic turnover, suggesting the potential for local adaptation. By understanding these spatial-environmental associations and linking them to life-history and metapopulation dynamics, we highlight opportunities to provide targeted species management. To support this, we have created habitat, connectivity, and genetic uniqueness maps for conservation decision-making in the region. These tools have the potential to provide a more holistic approach to conservation in multiuse landscapes globally.


La conservación a nivel del paisaje que incluye las dinámicas metapoblacionales será esencial para prevenir la declinación de especies con múltiples amenazas a su supervivencia. Enfocados en este fin, desarrollamos una estrategia novedosa que combina los registros presenciales, datos espacio-ambientales e información genética para modelar la conectividad de hábitat y los patrones de estructura genética y conectar los atributos espaciales con los mecanismos ecológicos subyacentes. Usamos al cuol del norte (Dasyurus hallucatus) como estudio de caso para aplicar esta estrategia y abordar la necesidad de herramientas de decisión en la conservación que promuevan metapoblaciones resilientes de esta especie en la Pilbara de Australia Occidental, un paisaje multiusos que es un punto caliente para la biodiversidad y la minería. Diferentes características del paisaje pronosticaron la conectividad y el hábitat. Mientras que la escabrosidad del terreno causó enormemente la idoneidad del hábitat, la dispersión estuvo propiciada por la proximidad a los cauces. Aunque hay evidencias limitadas de barreras físicas importantes en la Pilbara, las áreas con un contenido elevado de limo y arcilla (es decir, planicies aluviales y de alio) mostraron una gran resistencia a la dispersión. La matización climática determinó la distribución y los patrones del recambio genético, lo que sugiere un potencial para la adaptación local. Si entendemos estas asociaciones espacio-ambientales y las conectamos con las dinámicas metapoblacionales y de historia de vida, podemos resaltar las oportunidades para proporcionar un manejo focalizado de la especie. Para respaldar esto hemos creado mapas de hábitat, conectividad y singularidad genética para las decisiones de conservación en la región. Estas herramientas tienen el potencial de proporcionar una estrategia más holística para la conservación en los paisajes multiusos de todo el mundo.


Subject(s)
Conservation of Natural Resources , Endangered Species , Animals , Ecosystem , Biodiversity , Climate
3.
PLoS One ; 16(5): e0251304, 2021.
Article in English | MEDLINE | ID: mdl-33961676

ABSTRACT

Introduced mammalian predators can have devastating impacts on recipient ecosystems and disrupt native predator-prey relationships. Feral cats (Felis catus) have been implicated in the decline and extinction of many Australian native species and developing effective and affordable methods to control them is a national priority. While there has been considerable progress in the lethal control of feral cats, effective management at landscape scales has proved challenging. Justification of the allocation of resources to feral cat control programs requires demonstration of the conservation benefit baiting provides to native species susceptible to cat predation. Here, we examined the effectiveness of a landscape-scale Eradicat® baiting program to protect threatened northern quolls (Dasyurus hallucatus) from feral cat predation in a heterogeneous rocky landscape in the Pilbara region of Western Australia. We used camera traps and GPS collars fitted to feral cats to monitor changes in activity patterns of feral cats and northern quolls at a baited treatment site and unbaited reference site over four years. Feral cat populations appeared to be naturally sparse in our study area, and camera trap monitoring showed no significant effect of baiting on cat detections. However, mortality rates of collared feral cats ranged from 18-33% after baiting, indicating that the program was reducing cat numbers. Our study demonstrated that feral cat baiting had a positive effect on northern quoll populations, with evidence of range expansion at the treatment site. We suggest that the rugged rocky habitat preferred by northern quolls in the Pilbara buffered them to some extent from feral cat predation, and baiting was sufficient to demonstrate a positive effect in this relatively short-term project. A more strategic approach to feral cat management is likely to be required in the longer-term to maximise the efficacy of control programs and thereby improve the conservation outlook for susceptible threatened fauna.


Subject(s)
Animal Culling , Animals, Wild , Marsupialia , Animals , Cats , Ecosystem , Predatory Behavior , Western Australia
4.
Animals (Basel) ; 10(10)2020 Oct 19.
Article in English | MEDLINE | ID: mdl-33086546

ABSTRACT

The expansion of urban areas and associated clearing of habitat can have severe consequences for native wildlife. One option for managing wildlife in these situations is to relocate them. While there is a general perception that relocation is humane, transparency of outcomes is lacking. Here, we document the outcome of 122 western grey kangaroos (Macropus fuliginosus) relocated from an urban development site on the edge of Perth, Western Australia. Global Positioning System (GPS) or Very High Frequency (VHF) collars were fitted to 67 kangaroos, and their survival and movement were monitored over 12 months using telemetry, camera traps and spotlighting. Only six collared animals survived for the duration of the study with most dying within a week of the relocation, indicating stress associated with capture as the likely cause. By the completion of the study, 111 kangaroos were predicted to have died based on the proportion of individuals known to have died. Movement patterns of surviving GPS collared kangaroos changed over time from largely exploratory forays, to more repeated movements between focus areas within home ranges. The poor outcome here raises concerns around the viability of relocating a relatively large number of kangaroos as a management option. It also highlights the need for careful planning to limit the stress associated with capture and transport if relocations are to be used for managing kangaroos in urban areas.

5.
JMIR Public Health Surveill ; 6(2): e18844, 2020 04 06.
Article in English | MEDLINE | ID: mdl-32250283

ABSTRACT

BACKGROUND: The challenges faced by the Global South during the coronavirus disease (COVID-19) pandemic are compounded by the presence of informal settlements, which are typically densely populated and lacking in formalized sanitation infrastructure. Social distancing measures in informal settlements may be difficult to implement due to the density and layout of settlements. This study measures the distance between dwellings in informal settlements in Cape Town to identify the risk of COVID-19 transmission. OBJECTIVE: The aim of this paper is to determine if social distancing measures are achievable in informal settlements in Cape Town, using two settlements as an example. We will first examine the distance between dwellings and their first, second, and third nearest neighbors and then identify clusters of dwellings in which residents would be unable to effectively practice social isolation due to the close proximity of their homes. METHODS: Dwellings in the settlements of Masiphumelele and Klipfontein Glebe were extracted from a geographic information system data set of outlines of all informal dwellings in Cape Town. The distance to each dwelling's first, second, and third nearest neighbors was calculated for each settlement. A social distance measure of 2 m was used (buffer of 1 m, as dwellings less than 2 m apart are joined) to identify clusters of dwellings that are unable to effectively practice social distancing in each settlement. RESULTS: The distance to each dwelling's first 3 nearest neighbors illustrates that the settlement of Masiphumelele is constructed in a denser fashion as compared to the Klipfontein Glebe settlement. This implies that implementing social distancing will likely be more challenging in Masiphumelele than in Klipfontein Glebe. However, using a 2-m social distancing measure, it was demonstrated that large portions of Klipfontein Glebe would also be unable to effectively implement social distancing. CONCLUSIONS: Effectively implementing social distancing may be a challenge in informal settlements due to their density. This paper uses dwelling outlines for informal settlements in the city of Cape Town to demonstrate that with a 2 m measure, effective social distancing will be challenging.


Subject(s)
Betacoronavirus , Communicable Disease Control , Coronavirus Infections/transmission , Pneumonia, Viral/transmission , COVID-19 , Feasibility Studies , Humans , Pandemics , Risk Factors , SARS-CoV-2 , South Africa
6.
Diabetologia ; 63(3): 659-667, 2020 03.
Article in English | MEDLINE | ID: mdl-31848633

ABSTRACT

AIMS/HYPOTHESIS: Our aim was to investigate the geospatial distribution of diabetic foot ulceration (DFU), lower extremity amputation (LEA) and mortality rates in people with diabetes in small geographical areas with varying levels of multiple deprivation. METHODS: We undertook a population cohort study to extract the health records of 112,231 people with diabetes from the Scottish Care Information - Diabetes Collaboration (SCI-Diabetes) database. We linked this to health records to identify death, LEA and DFU events. These events were geospatially mapped using multiple deprivation maps for the geographical area of National Health Service (NHS) Greater Glasgow and Clyde. Tests of spatial autocorrelation and association were conducted to evaluate geographical variation and patterning, and the association between prevalence-adjusted outcome rates and multiple deprivation by quintile. RESULTS: Within our health board region, people with diabetes had crude prevalence-adjusted rates for DFU of 4.6% and for LEA of 1.3%, and an incidence rate of mortality preceded by either a DFU or LEA of 10.5 per 10,000 per year. Spatial autocorrelation identified statistically significant hot spot (high prevalence) and cold spot (low prevalence) clusters for all outcomes. Small-area maps effectively displayed near neighbour clustering across the health board geography. Disproportionately high numbers of hot spots within the most deprived quintile for DFU (p < 0.001), LEA (p < 0.001) and mortality (p < 0.001) rates were found. Conversely, a disproportionately higher number of cold spots was found within the least deprived quintile for LEA (p < 0.001). CONCLUSIONS/INTERPRETATION: In people with diabetes, DFU, LEA and mortality rates are associated with multiple deprivation and form geographical neighbourhood clusters.


Subject(s)
Cultural Deprivation , Diabetic Foot/diagnosis , Diabetic Foot/epidemiology , Aged , Aged, 80 and over , Cohort Studies , Diabetes Mellitus, Type 1/complications , Diabetes Mellitus, Type 1/diagnosis , Diabetes Mellitus, Type 1/epidemiology , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/diagnosis , Diabetes Mellitus, Type 2/epidemiology , Diabetic Foot/etiology , Diabetic Foot/therapy , Electronic Health Records/statistics & numerical data , Female , Geographic Mapping , Geography , Humans , Information Storage and Retrieval/statistics & numerical data , Male , Middle Aged , Patient Outcome Assessment , Prognosis , Retrospective Studies , Scotland/epidemiology , Socioeconomic Factors , Treatment Outcome
7.
Sci Total Environ ; 684: 381-389, 2019 Sep 20.
Article in English | MEDLINE | ID: mdl-31154211

ABSTRACT

Subterranean environments contain a diverse and unique obligate fauna: either aquatic living in the groundwater or terrestrial living in voids above the water table. In the arid region of the western part of the Australian continent, a particularly rich subterranean fauna coincides with a concentration of natural resource extraction operations. Since the inclusion of subterranean fauna in assessments of environmental impact in the mid-1990s, taxonomic research in Australia on this group of mainly invertebrates has grown exponentially. However, remaining knowledge gaps continue to frustrate both environmental regulators and development proponents due to high uncertainty in the decision-making process. In early 2017, the Western Australian Biodiversity Science Institute was tasked with leading the development of a research program to improve on the current state of knowledge of subterranean fauna. To balance the diverse environmental, economic and social needs of a range of stakeholders, transdisciplinary principles were applied to program development. A clear consensus on five broad focus areas to progress include: (1) data consolidation; (2) resilience to disturbance; (3) survey and sampling protocols; (4) abiotic and biotic habitat requirements; and (5) species delineation. In the context of these focus areas; we describe the research program development, reviewing the status of knowledge within each focus area, and the research initiatives to close the gaps in knowledge. We argue that, by adopting a transdisciplinary approach, the likelihood of success of the research program, as measured by the effective translation and adoption of research findings, will be maximized. This review is timely given the ever-increasing demand on groundwater systems for water extraction worldwide. A holistic understanding of the influence of anthropogenic activities on these ecosystems, and the functional role of organisms within them, will help to ensure that their health is not compromised.


Subject(s)
Ecosystem , Groundwater , Invertebrates/physiology , Life History Traits , Animals , Australia , Caves , Interdisciplinary Research , Invertebrates/classification
8.
Heliyon ; 4(7): e00693, 2018 Jul.
Article in English | MEDLINE | ID: mdl-30035238

ABSTRACT

Future land cover changes may result in adjustments to biophysical drivers impacting on net ecosystem carbon exchange (NEE), catchment water use through evapotranspiration (ET), and the surface energy balance through a change in albedo. The Land Change Modeller (Idrisi Terrset 18.08) and land cover for 2000 and 2014 are used to create a future scenario of land cover for two catchment with different land management systems in the Eastern Cape Province for the year 2030. In the S50E catchment, a dualistic farming system, the trend shows that grasslands represented 57% of the total catchment area in 2014 decreasing to 52% by 2030 with losses likely to favour a gain in woody plants and cultivated land. In T35B, a commercial system, persistence of grasslands is modelled with approximately 80% coverage in both years, representing a more stable system. Finally, for S50E, NEE and ET will increase under this land cover change scenario leading to increased carbon sequestration but less water availability and corresponding surface temperature increases. This implies that rehabilitation and land management initiatives should be targeted in catchments under a dualistic farming system, rather than those which are predominantly commercial systems.

9.
PLoS One ; 10(6): e0130721, 2015.
Article in English | MEDLINE | ID: mdl-26121581

ABSTRACT

Patch mosaic burning, in which fire is used to produce a mosaic of habitat patches representative of a range of fire histories ('pyrodiversity'), has been widely advocated to promote greater biodiversity. However, the details of desired fire mosaics for prescribed burning programs are often unspecified. Threatened small to medium-sized mammals (35 g to 5.5 kg) in the fire-prone tropical savannas of Australia appear to be particularly fire-sensitive. Consequently, a clear understanding of which properties of fire mosaics are most instrumental in influencing savanna mammal populations is critical. Here we use mammal capture data, remotely sensed fire information (i.e. time since last fire, fire frequency, frequency of late dry season fires, diversity of post-fire ages in 3 km radius, and spatial extent of recently burnt, intermediate and long unburnt habitat) and structural habitat attributes (including an index of cattle disturbance) to examine which characteristics of fire mosaics most influence mammals in the north-west Kimberley. We used general linear models to examine the relationship between fire mosaic and habitat attributes on total mammal abundance and richness, and the abundance of the most commonly detected species. Strong negative associations of mammal abundance and richness with frequency of late dry season fires, the spatial extent of recently burnt habitat (post-fire age <1 year within 3 km radius) and level of cattle disturbance were observed. Shrub cover was positively related to both mammal abundance and richness, and availability of rock crevices, ground vegetation cover and spatial extent of ≥4 years unburnt habitat were all positively associated with at least some of the mammal species modelled. We found little support for diversity of post-fire age classes in the models. Our results indicate that both a high frequency of intense late dry season fires and extensive, recently burnt vegetation are likely to be detrimental to mammals in the north Kimberley. A managed fire mosaic that reduces large scale and intense fires, including the retention of ≥4 years unburnt patches, will clearly benefit savanna mammals. We also highlighted the importance of fire mosaics that retain sufficient shelter for mammals. Along with fire, it is clear that grazing by introduced herbivores also needs to be reduced so that habitat quality is maintained.


Subject(s)
Fires , Grassland , Mammals/physiology , Animals , Australia , Biodiversity , Cattle , Geography , Surveys and Questionnaires
10.
PLoS One ; 9(12): e114095, 2014.
Article in English | MEDLINE | ID: mdl-25436454

ABSTRACT

The Montebello archipelago consists of 218 islands; 80 km from the north-west coast of Western Australia. Before 1912 the islands had a diverse terrestrial fauna. By 1952 several species were locally extinct. Between 1996 and 2011 rodents and cats were eradicated, and 5 mammal and 2 bird species were translocated to the islands. Monitoring of the broader terrestrial ecosystem over time has been limited. We used 20 dry-season Landsat images from 1988 to 2013 and estimation of green fraction cover in nadir photographs taken at 27 sites within the Montebello islands and six sites on Thevenard Island to assess change in vegetation density over time. Analysis of data averaged across the 26-year period suggests that 719 ha out of 2169 ha have increased in vegetation cover by up to 32%, 955 ha have remained stable and 0.6 ha have declined in vegetation cover. Over 492 ha (22%) had no vegetation cover at any time during the period analysed. Chronological clustering analysis identified two breakpoints in the average vegetation cover data occurring in 1997 and 2003, near the beginning and end of the rodent eradication activities. On many islands vegetation cover was declining prior to 1996 but increased after rodents were eradicated from the islands. Data for North West and Trimouille islands were analysed independently because of the potential confounding effect of native fauna being introduced to these islands. Mala (Lagorchestes hirsutus) and Shark Bay mice (Pseudomys fieldi) both appear to suppress native plant recruitment but not to the same degree as introduced rodents. Future research should assess whether the increase in vegetation cover on the Montebello islands is due to an increase in native or introduced plants.


Subject(s)
Conservation of Natural Resources , Pest Control , Plant Development , Rodentia , Animals , Conservation of Natural Resources/methods , Islands , Pest Control/methods , Rodentia/growth & development , Seasons , Telemetry/methods , Western Australia
11.
Article in English | MEDLINE | ID: mdl-12443940

ABSTRACT

The bilby (Macrotis lagotis) is a small omnivorous marsupial that was once widespread but is now restricted to the most arid margins of its former range. It feeds on a mixture of invertebrates (mainly ants and termites) and plant material (mainly seeds and bulbs), most of which is below ground. Measurements of the energy and water requirements of free-living bilbies and of the maintenance nitrogen requirements of captive animals provided the basis for an explanation for its continued survival in the Australian arid zone. Measurements of the mean retention times of inert markers for the solute and particulate phases of digesta revealed no selective retention of solutes and small particles in the caecum. Lack of selective digesta retention in the bilby hindgut helps to explain why the plant component of their diet consists predominantly of seeds and bulbs of relatively low fibre content. This is in contrast to the stems and leaves eaten by other bandicoots, all of which appear to have a colonic separation mechanism that not only selectively retains small particles in the caecum but also facilitates the passage of large fibrous particles through the colon. The ability of the bilby to survive in the Australian arid zone is related to low water and nitrogen requirements and the abundance of ants, termites, bulbs and seeds. Foraging efficiency is maximised by exploiting the underground nests of seed-harvesting ants.


Subject(s)
Animal Nutritional Physiological Phenomena , Ecosystem , Marsupialia/physiology , Adaptation, Physiological/physiology , Animals , Australia , Desert Climate
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