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Larval dispersal is the key process by which populations of most marine fishes and invertebrates are connected and replenished. Advances in larval tagging and genetics have enhanced our capacity to track larval dispersal, assess scales of population connectivity, and quantify larval exchange among no-take marine reserves and fished areas. Recent studies have found that reserves can be a significant source of recruits for populations up to 40 km away, but the scale and direction of larval connectivity across larger seascapes remain unknown. Here, we apply genetic parentage analysis to investigate larval dispersal patterns for two exploited coral reef groupers ( Plectropomus maculatus and Plectropomus leopardus) within and among three clusters of reefs separated by 60-220 km within the Great Barrier Reef Marine Park, Australia. A total of 69 juvenile P. maculatus and 17 juvenile P. leopardus (representing 6% and 9% of the total juveniles sampled, respectively) were genetically assigned to parent individuals on reefs within the study area. We identified both short-distance larval dispersal within regions (200 m to 50 km) and long-distance, multidirectional dispersal of up to ~250 km among regions. Dispersal strength declined significantly with distance, with best-fit dispersal kernels estimating median dispersal distances of ~110 km for P. maculatus and ~190 km for P. leopardus. Larval exchange among reefs demonstrates that established reserves form a highly connected network and contribute larvae for the replenishment of fished reefs at multiple spatial scales. Our findings highlight the potential for long-distance dispersal in an important group of reef fishes, and provide further evidence that effectively protected reserves can yield recruitment and sustainability benefits for exploited fish populations. [ABSTRACT FROM AUTHOR]

Based on the keynote at the 2014 Australian Generations research conference, this article maps the landscape of oral history practice in the digital age. Surveying all that is changing (and much that is not) it locates digital content management of interview recordings—exemplified by Australian Generations—at the centre of emerging practice. More broadly, the article explores meaningful access to content within and across interviews as a curatorial space and sensibility with transformative implications, given its location midway between the traditional focus either on conducting and archiving interviews (the raw), or producing and disseminating documentary or scholarly outputs (the cooked). [ABSTRACT FROM AUTHOR]

Photographic line transects were used to quantify the benthic community at Hall Bank, a small, nearshore, high-latitude reef in south-west Australia. On one of the seven transects, the coral cover was 72.5% (mean = 52.6 ± 0.45%), which is the highest ever recorded coral cover at or beyond 32°S. There were no macro-algae, possibly due to the high density of herbivorous sea-urchins (mean = 5.0 ± 0.8 m). Fourteen species of scleractinian corals dominated the benthos, seven of which were from the family Faviidae. Given that Hall Bank is at the limit of environmental tolerance for reef formation, it represents a valuable research opportunity for understanding the factors that build and maintain coral reef biodiversity and resilience. [ABSTRACT FROM AUTHOR]

Herpothallon biacidum Frisch et al. is described from Queensland, tropical Australia. The new species is characterized by a thick byssoid thallus that is loosely attached to the substratum, globular to claviform to short cylindrical pseudoisidia, a brown to brownish black hypothallus, and by the presence of gyrophoric and norstictic acids. This is the first reported co-occurrence of gyrophoric and norstictic acids in the genus. The differences between H. biacidum and other species containing either norstictic acid or gyrophoric acid are discussed. Herpothallon biacidum is also compared with Cryptothecia eungellaeae. Both occur in north Queensland and have the same chemistry, but the latter has a closely adnate thallus and lacks the dark hypothallus and pseudoisidia. The circumscription of Herpothallon and its distinction from Cryptothecia are discussed. [ABSTRACT FROM AUTHOR]

Understanding movements of palinurid (spiny) lobsters is important to fisheries management. However, movement data obtained with mark-capture techniques are often influenced by artefacts (e.g., displacement, tag-loss, tag-induced injury). To avoid these problems, a novel approach was employed to investigate the movements of an important coral reef palinurid, the painted lobster (Panulirus versicolor). Eighty adult individuals were captured by hand near Northwest Island, Australia. Each lobster was tagged internally (with elastomer) and externally (with plastic zip-ties) to enable both short- (1-10 days) and longterm (6-24 months) observations. Shortly thereafter, all lobsters were manually returned to their shelters (dens). After 6-24 months, 44 lobsters were recaptured, giving an overall recapture rate of 55%. All of these individuals were recaptured within 500 m of their original den, thus indicating a high level of site-fidelity for this species. Short-term observations revealed that individuals moved frequently to and from nearby dens, and that male lobsters typically moved further than female lobsters. It is hypothesized that male lobsters move about their home range more actively, perhaps to seek mating opportunities or to defend resources. The significance of these observations is discussed with respect to the management of this important fishery resource. [ABSTRACT FROM AUTHOR]

Abstract: Inter-specific genetic relationships among regional populations of two species of grouper (Plectropomus maculatus and Plectropomus leopardus) were examined using mitochondrial and nuclear markers. mtDNA revealed contrasting regional inter-specific patterns whilst nuclear markers revealed contrasting patterns among markers, irrespective of region. In eastern Australia (EA) the species form a single mtDNA lineage, but the two species are reciprocally monophyletic in Western Australia (WA). This supports previous evidence for hybridisation between these species on the east coast. WA P. leopardus forms a sister relationship with the EA P. leopardus-maculatus clade while WA P. maculatus is more basal and sister to the P. leopardus lineages, indicating mtDNA does not suffer from incomplete lineage sorting for these species. In contrast, one of three nuclear markers (locus 7-90TG) differentiated the species into two reciprocally monophyletic clades, with no evidence of hybridisation or ancestral polymorphism. The remaining two nuclear markers (2-22 and ETS-2) did not separate these two species, while distinguishing other plectropomid species, suggesting incomplete lineage sorting at these nuclear loci. These results together with coalescence analyses suggest that P. leopardus females have hybridised historically with P. maculatus males and that P. maculatus mitochondria were displaced through introgressive hybridisation and fixation in the P. maculatus founder population on the Great Barrier Reef. The contrasting regional patterns of mtDNA structure may be attributed to Quaternary sea-level changes and shelf width differences driving different reef configurations on each coast. These reef configurations have provided opportunities for local scale interaction and reproduction among species on the narrower EA continental shelves, but not on the broader WA continental shelves. [Copyright &y& Elsevier]