Can we mitigate cane toad impacts on northern quolls?

Made available by the Northern Territory Library via the Publications (Legal Deposit) Act 2004 (NT).'The spread of the toxic cane toad Rhinella marina threatens populations of the endangered northern quoll Dasyurus hallucatus. We identified quoll populations at risk from toad invasion in the central Kimberley and explored whether free ranging quolls would consume ?toad-aversion? baits that induce aversions to live toads. A long-term study in Kakadu National Park showed that each generation of quolls learns to avoid toads, so one deployment of toad-aversion baits could protect quolls from toads. Encouragingly, 50% of wild quolls at Sir John Gorge, Mornington Wildlife Sanctuary (central Kimberley) consumed toad-aversion sausages. More research on captive quolls is necessary to develop long-lasting toad-aversion baits suitable for aerial deployment.' SummarySummary -- Focus and significance of the project -- Distinctiveness of issue to this landscape -- Knowledge status and constraints -- Methodological approaches -- Lessons learnt for this landscape -- National implications of lessons learnt -- Problems addressing the focus and how to overcome these -- Towards implementation -- Looking ahead - future needs -- ReferencesOn cover: Kakadu National Park, National Environmental Research Program Northern Australia Hub, Australian Wildlife Conservancy and University of Technology, Sydney

Integrative taxonomic investigation of Petaurus breviceps (Marsupialia: Petauridae) reveals three distinct species

The Australian sugar glider, Petaurus breviceps s.l., is widely distributed across eastern and northern Australia. Examination of historical and contemporary collections of Petaurus specimens and phylogenetic analyses have revealed considerable taxonomic diversity within the genus. We aimed to utilize an integrative taxonomic approach, combining genetic and morphological evidence, to resolve the taxonomy of Australian gliders currently recognized as Petaurus breviceps. Herein, we confirm the existence of three distinct species: P. breviceps, P. notatus comb. nov. and P. ariel comb. nov.. Petaurus breviceps and P. notatus are each represented by major mtDNA lineages in P. breviceps, while P. ariel forms a sister-lineage to P. norfolcensis and P. gracilis. Subtle morphological differences distinguish P. breviceps from the closely related P. notatus, while the morphological distinctions between P. ariel and its genetically similar sister-taxa, P. norfolcensis and P. gracilis, are more obvious. Given the purported broad geographic distribution of the taxon, P. breviceps s.l. was not listed as threatened, but dividing this taxon into three species has important conservation implications for all taxa in the group, particularly given the lamentable record for mammal extinctions in Australia. Concerted and targeted conservation efforts are necessary to preserve these distinct, newly described species

Population genomics of a predatory mammal reveals patterns of decline and impacts of exposure to toxic toads

Mammal declines across northern Australia are one of the major biodiversity loss events occurring globally. There has been no regional assessment of the implications of these species declines for genomic diversity. To address this, we conducted a species-wide assessment of genomic diversity in the northern quoll (Dasyurus hallucatus), an Endangered marsupial carnivore. We used next generation sequencing methods to genotype 10,191 single nucleotide polymorphisms (SNPs) in 352 individuals from across a 3220-km length of the continent, investigating patterns of population genomic structure and diversity, and identifying loci showing signals of putative selection. We found strong heterogeneity in the distribution of genomic diversity across the continent, characterized by (i) biogeographical barriers driving hierarchical population structure through long-term isolation, and (ii) severe reductions in diversity resulting from population declines, exacerbated by the spread of introduced toxic cane toads (Rhinella marina). These results warn of a large ongoing loss of genomic diversity and associated adaptive capacity as mammals decline across northern Australia. Encouragingly, populations of the northern quoll established on toad-free islands by translocations appear to have maintained most of the initial genomic diversity after 16 years. By mapping patterns of genomic diversity within and among populations, and investigating these patterns in the context of population declines, we can provide conservation managers with data critical to informed decision-making. This includes the identification of populations that are candidates for genetic management, the importance of remnant island and insurance/translocated populations for the conservation of genetic diversity, and the characterization of putative evolutionarily significant units.</p