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Short-tailed Shearwaters (Puffinus tenuirostris) are a numerous, colonially nesting seabird that is strongly philopatric. We applied restriction-enzyme analysis of mitochondrial DNA (mtDNA) to 335 individuals from 11 colonies across southeastern Australia to assess population-genetic structure and the amount of genetic variability in this species. Eleven 6/5.33-base and four 4-base restriction enzymes revealed 25 and 48 mtDNA haplotypes in two overlapping surveys of 215 individuals from seven colonies and 231 individuals from eight colonies, respectively. A low mean sequence diversity among individuals (0.247%) and lack of spatial structuring of mtDNA haplotypes suggest a lack of population-genetic structure and a reduced ancestral population size during glaciation, followed by a population and range expansion. Intracolony mtDNA diversities in three recently established colonies and in one colony that has experienced a recent bottleneck were comparable to mtDNA diversities within larger and older colonies. This suggests that, despite strict philopatry in those colonies, colony founding and recovery from population reduction occurs via immigration of a large number of individuals.

The article is a recollection of the ups and downs of my career as a research scientist. It does not chronicle my career in the standard way; there is no timeline of events and only a few details of the type of research that I have devoted my life to. I feel the take-home messages are relevant no matter what type of science you do. The narrative jumps around between periods of my life, uses anecdotes freely and attempts to be informative, forthright, and entertaining. Although science is perceived as a profession, the career pathway can be uneven and forked. In addition to discipline-specific knowledge and experience, successful scientists need a multitude of skills; for instance, human management, logistics, and social media—to name a few. The field often attracts talented introverts for whom working in teams is challenging. The complexity of science is fascinating and powerful. In the fervour for discoveries, care is needed not to become isolated from friends and family by long working hours. For those of you who have gone part or full way down this path, there will be value in comparing your experiences to mine. Mostly I hope that younger scientists who are beginning on this path, or considering whether to enter, will take away some messages that will help them stand on our shoulders. [ABSTRACT FROM AUTHOR]

Molecular genetic estimates of population effective size (Ne) lose accuracy and precision when insufficient numbers of samples or loci are used. Ideally, researchers would like to forecast the necessary power when planning their project. neogen (genetic Ne for Overlapping Generations) enables estimates of precision and accuracy in advance of empirical investigation and allows exploration of the power available in different user‐specified age‐structured sampling schemes. neogen provides a population simulation and genetic power analysis framework that simulates the demographics, genetic composition, and Ne, from species‐specific life history, mortality, population size, and genetic priors. neogen guides the user to establish a tractable sampling regime and to determine the numbers of samples and microsatellite or SNP loci required for accurate and precise genetic Ne estimates when sampling a natural population. neogen is useful at multiple stages of a study's life cycle: when budgeting, as sampling and locus development progresses, and for corroboration when empirical Ne estimates are available. The underlying model is applicable to a wide variety of iteroparous species with overlapping generations (e.g., mammals, birds, reptiles, long‐lived fishes). In this paper, we describe the neogen model, detail the workflow for the point‐and‐click software, and explain the graphical results. We demonstrate the use of neogen with empirical Australian east coast zebra shark (Stegostoma fasciatum) data. For researchers wishing to make accurate and precise genetic Ne estimates for overlapping generations species, neogen facilitates planning for sample and locus acquisition, and with existing empirical genetic Ne estimates neogen can corroborate population demographic and life history properties. [ABSTRACT FROM AUTHOR]

As pressure on coastal marine resources is increasing globally, the need to quantitatively assess vulnerable fish stocks is crucial in order to avoid the ecological consequences of stock depletions. Species of Sciaenidae (croakers, drums) are important components of tropical and temperate fisheries and are especially vulnerable to exploitation. The black-spotted croaker, Protonibea diacanthus, is the only large sciaenid in coastal waters of northern Australia where it is targeted by commercial, recreational and indigenous fishers due to its food value and predictable aggregating behaviour. Localized declines in the abundance of this species have been observed, highlighting the urgent requirement by managers for information on fine- and broad-scale population connectivity. This study examined the population structure of P. diacanthus across north-western Australia using three complementary methods: genetic variation in microsatellite markers, otolith elemental composition and parasite assemblage composition. The genetic analyses demonstrated that there were at least five genetically distinct populations across the study region, with gene flow most likely restricted by inshore biogeographic barriers such as the Dampier Peninsula. The otolith chemistry and parasite analyses also revealed strong spatial variation among locations within broad-scale regions, suggesting fine-scale location fidelity within the lifetimes of individual fish. The complementarity of the three techniques elucidated patterns of connectivity over a range of spatial and temporal scales. We conclude that fisheries stock assessments and management are required at fine scales (100 s of km) to account for the restricted exchange among populations (stocks) and to prevent localized extirpations of this species. Realistic management arrangements may involve the successive closure and opening of fishing areas to reduce fishing pressure. [ABSTRACT FROM AUTHOR]