The 2023 Whippoorwill Award: The 2023 Whippoorwill Award: Complex Representations of Rural Identities and Places

Announcing the 2023 Whippoorwill Award winners

Prioritising search effort to locate previously unknown populations of endangered marine reptiles

Strategies aimed to conserve and manage rare species are often hindered by the lack of data needed for their effective design. Incomplete and inaccurate data on habitat associations and current species distributions pose a barrier to effective conservation and management for several species of endemic sea snakes in Western Australia that are thought to be in decline. Here we used a correlative modelling approach to understand habitat associations and identify suitable habitats for five of these species (Aipysurus apraefrontalis, A. foliosquama, A. fuscus, A. l. pooleorum and A. tenuis). We modelled species-specific habitat suitability across 804,244 km(2) of coastal waters along the North-west Shelf of Western Australia, to prioritise future survey regions to locate unknown populations of these rare species. Model projections were also used to quantify the effectiveness of current spatial management strategies (Marine Protected Areas) in conserving important habitats for these species. Species-specific models matched well with the records on which they were trained, and identified additional regions of suitability without records. Subsequent field validation of the model projections uncovered a previously unknown locality for A. fuscus within the mid-shelf shoal region, outside its currently recognised global range. Defining accurate geographic distributions for rare species is a vital first step in defining more robust extent of species occurrence and range overlap with threatening processes

The long-term dynamics of invasive signal crayfish forcing of fluvial sediment supply via riverbank burrowing

Animals are important drivers of sediment dynamics. Invasive signal crayfish (Pacifastacus leniusculus) have been shown to supply sediment to rivers by burrowing into riverbanks. Burrowing directly transfers excavated sediment into the river and also has an additional indirect affect by promoting riverbank failure. While previous research has isolated burrow densities at a point in time, rates of burrow construction and of burrow loss due to erosion are unknown, which introduces uncertainty into estimates of how much sediment burrows contribute to rivers. Here we report results from a 5-year study that evaluated the temporal dynamics of crayfish populations, rates of burrow loss due to erosion, and the mass of sediment directly supplied to rivers by burrow excavation. At ten reaches across five lowland streams in England, we estimated the mass of sediment displaced by 1861 new and previously constructed burrows. Both crayfish and burrow densities were variable over time, suggesting that burrows contribute temporally variable amounts of fine sediment to riverine systems. 42 % of observed burrows were constructed within the previous 365 days, and individual burrows lasted on average 461 days. Applying this to comparable historical data, an average of 2.0 t km−1 a−1 of sediment was excavated to construct burrows in the study reaches, which is eight times more than estimated in previous studies. Whilst total burrow densities in each year were not consistently correlated with contemporary crayfish densities, the mass of sediment excavated over the prior year was strongly correlated with contemporary crayfish densities. Current fine sediment management practices are largely aimed at controlling fine sediment delivery, predominately from agricultural activities, but biotic burrowing into riverbanks may represent an important and overlooked source of fine sediment supply. Incorporation of biotic processes in sediment dynamics would improve the accuracy of fluvial sediment budgets and enhance the knowledge base underpinning effective fine-sediment management practices

The role of social identity and self-efficacy in predicting service providers’ use of Stepping Stones Triple P following training

Background: Identifying factors that may contribute to the use of programs following the completion of training by practitioners is of practical and theoretical importance. Aim: This study examined the role of social identity and self-efficacy in contributing to the delivery of an evidence-based parenting program. Methods and Procedures: A sample of 63 multi-disciplinary professionals trained in the Stepping Stones Triple P-Positive Parenting Program, for parents of children with developmental disability, as part of a statewide roll-out were interviewed two years after training. Data on the number of hours of delivery during the 2-year period was analysed along with quantitative data obtained during interviews that assessed professionals’ self-efficacy and social identity as a Stepping Stones professional. Outcomes and Results: Social identity was associated with the use of SSTP in an independent analysis, but the association was no longer significant when other factors were included in a regression model. Self-efficacy predicted the use of SSTP and was found to be a mediator in the relationship between social identity and use of SSTP. Conclusions and Implications: This first investigation into the role of social identity in the implementation of evidence-based parenting programs showed that social identity could play an important role. The role of self-efficacy in predicting program use was further supported in this study and the mediator function of self-efficacy is explored. The practical and theoretical implications of the role of self-efficacy and social identity in the training of professionals are discussed.</p

New environment, new invaders - repeated horizontal transfer of LINEs to sea snakes

While numerous studies have found horizontal transposon transfer (HTT) to be widespread across metazoans, few have focused on HTT in marine ecosystems. To investigate potential recent HTTs into marine species we searched for novel repetitive elements in sea snakes, a group of elapids which transitioned to a marine habitat at most 18 Mya. Our analysis uncovered repeated HTTs into sea snakes following their marine transition. The 7 subfamilies of horizontally transferred LINE retrotransposons we identified in the olive sea snake (Aipysurus laevis) are transcribed, and hence are likely still active and expanding across the genome. A search of 600 metazoan genomes found all 7 were absent from other amniotes, including terrestrial elapids, with the most similar LINEs present in fish and marine invertebrates. The one exception was a similar LINE found in sea kraits, a lineage of amphibious elapids which independently transitioned to a marine environment 25 Mya. Our finding of repeated horizontal transfer events into marine snakes greatly expands past findingst that the marine environment promotes the transfer of transposons. Transposons are drivers of evolution as sources of genomic sequence and hence genomic novelty. We identified 13 candidate genes for HTT-induced adaptive change based on internal or neighbouring HTT LINE insertions. One of these, ADCY4, is of particular interest as a part of the KEGG adaptation pathway "Circadian Entrainment". This provides evidence of the ecological interactions between species influencing evolution of metazoans not only through specific selection pressures, but also by contributing novel genomic material

Dense molecular gas in quasar host galaxies: a search for HCN emission from BR B1202-0725 at z=4.695

We report on the results of a search using the VLA for redshifted HCN(1-0) emission from the host galaxy of BR B1202-0725, an optically luminous quasar at z=4.695. The host galaxy emits strongly in the rest-frame far-infrared, and shows characteristics very similar to that of more local, ultraluminous infrared galaxies, in which a significant fraction of the far-infrared emission is powered by star formation. We find a 3-sigma upper limit to the HCN(1-0) emission of 4.9 x 10^10 K kms^-1 pc^2, assuming a lambda-cosmology. This limit is consistent with correlations derived from measurements of the HCN, CO, and far-infrared emission for a sample of more local galaxies, including starbursts (Solomon et al, 1992a)

Observations of Arp 220 using Herschel-SPIRE: An Unprecedented View of the Molecular Gas in an Extreme Star Formation Environment

We present Herschel SPIRE-FTS observations of Arp~220, a nearby ULIRG. The FTS continuously covers 190 -- 670 microns, providing a good measurement of the continuum and detection of several molecular and atomic species. We detect luminous CO (J = 4-3 to 13-12) and water ladders with comparable total luminosity; very high-J HCN absorption; OH+, H2O+, and HF in absorption; and CI and NII. Modeling of the continuum yields warm dust, with T = 66 K, and an unusually large optical depth of ~5 at 100 microns. Non-LTE modeling of the CO shows two temperature components: cold molecular gas at T ~ 50 K and warm molecular gas at T ~1350 K. The mass of the warm gas is 10% of the cold gas, but dominates the luminosity of the CO ladder. The temperature of the warm gas is in excellent agreement with H2 rotational lines. At 1350 K, H2 dominates the cooling (~20 L_sun/M_sun) in the ISM compared to CO (~0.4 L_sun/M_sun). We found that only a non-ionizing source such as the mechanical energy from supernovae and stellar winds can excite the warm gas and satisfy the energy budget of ~20 L_sun/M_sun. We detect a massive molecular outflow in Arp 220 from the analysis of strong P-Cygni line profiles observed in OH+, H2O+, and H2O. The outflow has a mass > 10^{7} M_sun and is bound to the nuclei with velocity < 250 km/s. The large column densities observed for these molecular ions strongly favor the existence of an X-ray luminous AGN (10^{44} ergs/s) in Arp 220.Comment: Accepted in ApJ on September 1, 201

Horizontal transposon transfer and its implications for the ancestral ecology of hydrophiine snakes

Transposable elements (TEs), also known as jumping genes, are sequences able to move or copy themselves within a genome. As TEs move throughout genomes they often act as a source of genetic novelty, hence understanding TE evolution within lineages may help in understanding environmental adaptation. Studies into the TE content of lineages of mammals such as bats have uncovered horizontal transposon transfer (HTT) into these lineages, with squamates often also containing the same TEs. Despite the repeated finding of HTT into squamates, little comparative research has examined the evolution of TEs within squamates. Here we examine a diverse family of Australo–Melanesian snakes (Hydrophiinae) to examine if the previously identified, order-wide pattern of variable TE content and activity holds true on a smaller scale. Hydrophiinae diverged from Asian elapids ~30 Mya and have since rapidly diversified into six amphibious, ~60 marine and ~100 terrestrial species that fill a broad range of ecological niches. We find TE diversity and expansion differs between hydrophiines and their Asian relatives and identify multiple HTTs into Hydrophiinae, including three likely transferred into the ancestral hydrophiine from fish. These HTT events provide the first tangible evidence that Hydrophiinae reached Australia from Asia via a marine route