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Biology subjects

Maurer, G.

Publications and source records attributed to Maurer, G..

2 recordsLinked to original sources

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↗

Elephant endotheliotropic herpesvirus is omnipresent in elephants in European zoos and an Asian elephant range country

Elephant endotheliotropic herpesviruses (EEHVs) are a group of evolutionary divergent herpesviruses that may cause acute, often lethal, hemorrhagic disease (EEHV-HD) in young elephants. Although EEHV was first discovered over 20 years ago, its prevalence in different elephant populations is still largely unknown, partially due to the lack of readily available, sensitive serological assays. In order to improve diagnostic tools for the detection of EEHV infections and to obtain insight in its spread among elephants, we developed novel ELISAs focusing on EEHV1A gB and gH/gL as antigens. Performance of the ELISAs was assessed using sera taken from 41 European zoo elephants and 69 semi-captive elephants from Laos, one of the Asian elephant range countries. Sera from all (sub)adult animals tested ([≥]5 years of age) showed high reactivity with both gB and gH/gL, whereas reactivity towards the antigens was generally lower for sera of juvenile animals (1 > 5 years). Only one (juvenile) animal, which was sampled directly after succumbing to EEHV-HD, was found to be seronegative for EEHV. The two other EEHV-HD cases tested showed low antibody levels, suggesting that all three cases died upon a primary EEHV infection. Direct comparison with another EEHV-specific ELISA previously used in two large serosurveys, showed that EEHV prevalence was underestimated before, likely due to aberrant folding of the antigen used. In conclusion, our study suggests that essentially all (semi-)captive (sub)adult elephants in European zoos and in Laos carry EEHV, and that young elephants with low antibody levels are at risk of dying from EEHV-HD. ImportanceOver the last 30 years, nearly 20% of all Asian elephants born in Western zoos succumbed to acute hemorrhagic disease caused by elephant endotheliotropic herpesvirus (EEHV-HD). Yet, the prevalence of EEHV in captive and wild elephant populations is still largely unknown, mainly due to the lack of readily available, sensitive serological assays. For this study two highly sensitive EEHV-specific ELISAs were developed. Using these assays, it was shown that nearly all elephants tested were seropositive for EEHV, with highest antibody levels detected in (sub)adult elephants. In contrast, antibody levels in EEHV-HD cases were very low or non-detectable. Lack of antibodies may thus be a risk factor for developing severe disease. As the novel ELISAs are low-tech in nature, these assays may easily be disseminated to local laboratories in zoos and elephant range countries in order to determine EEHV serostatus of individual animals or complete herds and (wild) populations.

microbiology↗