Studies in Canarium urceus (Linné, 1758) Part 4: Canarium (Canarium) orrae (Abbott, 1960) (Gastropoda: Neostromboidae: Strombidae) and a new species from the Northern Territory, Australia

This part of the Canarium (Canarium) urceus (Linné, 1758) after Abbott (1960) revision examines the Australian species of that complex. Currently, there is one recognised species, Canarium (Canarium) orrae (Abbott, 1960), which is divided herein into two species, with the description of Canarium (Canarium) darwinense n. sp. from the Van Diemen Gulf and Darwin surrounds. The C. (C.) darwinense is distinguished from C. (C.) orrae in morphological form. The southern range of C. (C.) orrae is extended to Monkey Mia, Shark Bay. Examples of C. (C.) orrae were also noted from the North Coast of Sumbawa, Indonesia, and Port Moresby, Papua New Guinea. While there is a geographic break in the distribution of C. (C.) orrae creating two populations, Western Australian and Gulf of Carpentaria, populations from these two ranges could not be distinguished using morphology. Future research will likely show genetic differences as a consequence of drift caused by isolation, thus leading to the potential recognition of two cryptic subspecies.

Microfabric features of microbial carbonates: experimental and natural evidence of mold holes and crusts

Results of our study based on examination of induced precipitation of carbonate by a cyanobacterium, Lyngbya in the laboratory, and the analyses of microphotographs of both modern and ancient microbial carbonates, demonstrated the importance of recognition of mold holes and carbonate crusts in understanding microbial carbonates. In the experiment, only cyanobacteria Lyngbya can induce precipitation of carbonate, forming scattered grains on the surface of Lyngbya filaments. Carbonate crusts enclosing the old parts of the filaments were formed through aggregation of these scatter grains while mold holes were formed after decay of the filaments. Mainly based on the experiment, six different ways of microbial carbonate formation were recognized: (1) trapping without mold holes, (2) trapping with mold holes, (3) particle-forming induced-precipitation of carbonate, (4) discrete crust-forming induced-precipitation of carbonate, (5) induced precipitation, forming tangled crusts that build a porous construction, and (6) induced precipitation, forming a dense construction. And mold holes and crusts can form in ways (4), (5), and (6). Examination of both modern microbial carbonates from the Shark Bay of Australia, Highborne Cay of Bahamas and the atoll of Kiritimati and the microbialites from the Cambrian dolostone sequence in Tarim, Xinjiang, China all demonstrated the limitation of recognizing only mesofabric features and importance of examining microfabric features for understanding of the genesis of the microbial carbonates and their proper classification. The shape, size and arrangement of the mold holes, crusts, and the features of the minerals filling in pores between the crusts, which are referred as the microfabric features here, are keys to better understand the formation and environments of both modern and ancient microbial carbonates.

Two species, one island: Retrospective analysis of threatened fauna translocations with divergent outcomes

Translocations are globally a popular tool used with the intention of improving threatened species conservation and re-establishing ecosystem function. While practitioners strive for successful outcomes the failure rate of translocations continues to be high. We demonstrate how predictive modelling can contribute to more informed decision making and hence potentially improve the success rate of translocation programs. Two species, the Djoongari (Shark Bay mouse) Pseudomys fieldi and the golden bandicoot Isoodon auratus barrowensis, were introduced independently to Doole Island in the Exmouth Gulf of Western Australia. We used population viability analysis to critique the outcomes of these translocations and provide an example of how this tool can be incorporated with expert knowledge to predict likely outcomes of translocations. Djoongari did not establish on the island after seven translocations over nine years, while golden bandicoots established a population after just one release event. Retrospective population viability analysis (of data that was unavailable prior to the translocations) predicted and clarified the reasons behind the outcomes of both translocations. Golden bandicoots have considerably higher demographic plasticity than Djoongari, which were never likely to establish on the island. We conclude that the failure of the Djoongari translocation was due to interactions between sparse habitat, native predators and cyclonic storm surges, whereas golden bandicoots have demonstrated habitat flexibility and an ability to recover from multiple natural disasters. As a result we (1) remind conservation planners of the importance of quantifying likely refuges and habitat availability at release sites, (2) suggest practitioners consider how different threats (including natural disasters) may interact at potential release sites and (3) advocate for the incorporation of predictive modelling during the planning stages of translocations, particularly for conservation introductions where no precedent exists for the species’ survival at a particular location.

Museum genomics reveals the rapid decline and extinction of Australian rodents since European settlement

Australia has the highest historically recorded rate of mammalian extinction in the world, with 34 terrestrial species declared extinct since European colonization in 1788. Among Australian mammals, rodents have been the most severely affected by these recent extinctions; however, given a sparse historical record, the scale and timing of their decline remain unresolved. Using museum specimens up to 184 y old, we generate genomic-scale data from across the entire assemblage of Australian hydromyine rodents (i.e., eight extinct species and their 42 living relatives). We reconstruct a phylogenomic tree for these species spanning ∼5.2 million years, revealing a cumulative total of 10 million years (>10%) of unique evolutionary history lost to extinction within the past ∼150 y. We find no evidence for reduced genetic diversity in extinct species just prior to or during decline, indicating that their extinction was extremely rapid. This suggests that populations of extinct Australian rodents were large prior to European colonization, and that genetic diversity does not necessarily protect species from catastrophic extinction. In addition, comparative analyses suggest that body size and biome interact to predict extinction and decline, with larger species more likely to go extinct. Finally, we taxonomically resurrect a species from extinction, Gould’s mouse (Pseudomys gouldii Waterhouse, 1839), which survives as an island population in Shark Bay, Western Australia (currently classified as Pseudomys fieldi Waite, 1896). With unprecedented sampling across a radiation of extinct and living species, we unlock a previously inaccessible historical perspective on extinction in Australia. Our results highlight the capacity of collections-based research to inform conservation and management of persisting species.

Performance Analysis of Offshore Mono-Pile Wind Turbine Co-Located With Floating Photovoltaic Systems in Shark Bay, Australia

In recent years, as more offshore wind farms have been constructed, the possibility of integrating various offshore renewable technologies is increased. Using offshore wind and solar power resources as a hybrid system provides several advantages including optimized marine space utilization, reduced maintenance and operation costs, and relieving wind variability on output power. In this research, both offshore wind and solar resources are analyzed based on accurate data through a case study in Shark Bay (Australia), where bathymetric information confirms using offshore bottom-fixed wind turbine regarding the depth of water. Also, the power production of the hybrid system of co-located bottom-fixed wind turbine and floating photovoltaic are investigated with the technical characteristics of commercial mono-pile wind turbine and photovoltaic panels. Despite the offshore wind, the solar energy output has negligible variation across the case study area, therefore using the solar platform in deep water is not an efficient option. It is demonstrated that the floating solar has a power production rate nearly six times more than a typical offshore wind farm with the same occupied area. Also, output energy and surface power density of the hybrid offshore windsolar system are improved significantly compared to a standalone offshore wind farm. The benefits of offshore wind and solar synergies augment the efficiency of current offshore wind farms throughout the world.

Cooperation-based concept formation in male bottlenose dolphins

In Shark Bay, Western Australia, male bottlenose dolphins form a complex nested alliance hierarchy. At the first level, pairs or trios of unrelated males cooperate to herd individual females. Multiple first-order alliances cooperate in teams (second-order alliances) in the pursuit and defence of females, and multiple teams also work together (third-order alliances). Yet it remains unknown how dolphins classify these nested alliance relationships. We use 30 years of behavioural data combined with 40 contemporary sound playback experiments to 14 allied males, recording responses with drone-mounted video and a hydrophone array. We show that males form a first-person social concept of cooperative team membership at the second-order alliance level, independently of first-order alliance history and current relationship strength across all three alliance levels. Such associative concepts develop through experience and likely played an important role in the cooperative behaviour of early humans. These results provide evidence that cooperation-based concepts are not unique to humans, occurring in other animal societies with extensive cooperation between non-kin.