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Determining the genetic diversity and differentiation among populations is a critical element of conservation biology, but for many aquatic, data-deficient species with small population sizes, this is not possible. Closely related species may therefore provide a model. For the first time, using over 4000 single-nucleotide polymorphism loci, we characterise the population genetic diversity and structure of one of the world’s rarest marine fish, the spotted handfish (Brachionichthys hirsutus), a species which is also a member of the most threatened marine bony fish family (Brachionichthyidae). Fin clips were taken from 170 live spotted handfish across seven disjunct sites within the only known estuary (in Tasmania, Australia) where multiple populations of the species are found. Spatially discrete populations clustered into three genetic groupings and a significant variance in allele frequencies among populations (overall FST = 0.043), even at the small scale of the estuary, was observed. Furthermore, low contemporary migration rate estimates suggest low genetic homogeneity between locations. Because of the low genetic connectivity, population clusters of spotted handfish within the estuary should be considered as separate conservation management units. This insight should be considered for management and conservation strategies of other data-deficient and threatened species in the family.

Recreational fishing (RF) is a popular pastime resulting in substantial fish mortality in many regions. Yet inclusion of RF in fishery harvest strategies is limited, because the sector's objectives are poorly understood, as are the data required to track their performance. To address this, we reviewed RF data sources available from a region of globally high participation (New South Wales [NSW], Australia) and evaluated their utility for RF-specific performance indicators within harvest strategies. We then linked these data sources to RF objectives they may be used to monitor. A total of 21 RF data sources were identified in NSW over the past two decades, spanning all major aquatic environments and 146 fished species. Numerous data sources were available to monitor ecological objectives, providing time-series and potential reference points for key indicators such as catch-per-unit-effort. Few data sources were available for social, economic, and institutional objectives, consistent with a global paucity of these data. We found that most social objectives of RF lie outside the scope of traditional harvest strategies, although some are linked to underlying ecological performance. Harvest strategy performance for RF will depend on the relative importance of social objectives and whether these can be achieved by controlling harvest.

When monitoring marine recreational fishers at sub-bio-regional scales—for example those who are accessing a Marine Park—on-site sampling is often required. This poses various logistical challenges, such as the efficient timing of intercept interviews. Here, we examine these challenges, combining trail cameras, closed-circuit television (CCTV), weather stations, and interviews at boat ramps that bracket an offshore Marine Park. Trail camera results were similar to those from a CCTV system co-located at one of the boat ramps. Fishers’ boat launches peaked early, but return times varied considerably by ramp and weather. Both the numbers of launches and trip durations were strongly responsive to good weather, particularly at ramps used for offshore fishing. Weather was a more important factor to predict the likelihood of intercept interview opportunities than holiday period, which may reflect changing dynamics in work culture and improvements in weather prediction. Interviewed fishers reported preferences to individual ramps over the fishing season and nearly all trips to the Marine Park were reported by fishers accessing just one ramp. The strong relationships between fishing, weather, and ramp, observed by the trail camera and correlated with the weather station data, may allow for the efficient targeting of intercept interviews and potentially the modelling of fishing effort.

Recreational fishing is popular in Australia and is managed by individual states in consultation with the Commonwealth for those fisheries that they regulate and also for Australian Marine Parks (AMPs). Fishers regularly access both state and offshore Commonwealth waters but this offshore component of the recreational fishery is poorly understood. Our study tested the functionality of existing state-based surveys in Western Australia (WA) and New South Wales (NSW) to better inform Commonwealth fisheries and AMP managers about recreational fishing in their jurisdictions. Catch estimates for nine species of interest to the Commonwealth were developed and two case study AMPs [Ningaloo (WA) and The Hunter (NSW)] were also chosen to test the ability of the state survey data to be disaggregated to the park scale. As each state’s fishery survey designs were contextual to their own management needs, the application of the data to Commonwealth jurisdictions were limited by their statistical power, however aspects of each states surveys still provided useful information. Continued evolution of state-wide survey methods, including collection of precise spatial data, and regional over-sampling would be beneficial, particularly where there are multiple stakeholder and jurisdictional interests. National coordination, to temporally align state surveys, would also add value to the existing approaches.

Collecting data on unlicensed open‐access coastal activities, such as some types of recreational fishing, has often relied on telephone interviews selected from landline directories. However, this approach is becoming obsolete due to changes in communication technology such as a switch to unlisted mobile phones. Other methods, such as boat ramp interviews, are often impractical due to high labor cost. We trialed an autonomous, ultra‐high‐resolution photosampling method as a cost effect solution for direct measurements of a recreational fishery. Our sequential photosampling was batched processed using a novel software application to produce “big data” time series movies from a spatial subset of the fishery, and we validated this with a regional bus‐route survey and interviews with participants at access points. We also compared labor costs between these two methods. Most trailer boat users were recreational fishers targeting tuna spp. Our camera system closely matched trends in temporal variation from the larger scale regional survey, but as the camera data were at much higher frequency, we could additionally describe strong, daily variability in effort. Peaks were normally associated with weekends, but consecutive weekend tuna fishing competitions led to an anomaly of high effort across the normal weekday lulls. By reducing field time and batch processing imagery, Monthly labor costs for the camera sampling were a quarter of the bus‐route survey; and individual camera samples cost 2.5% of bus route samples to obtain. Gigapixel panoramic camera observations of fishing were representative of the temporal variability of regional fishing effort and could be used to develop a cost‐efficient index. High‐frequency sampling had the added benefit of being more likely to detect abnormal patterns of use. Combinations of remote sensing and on‐site interviews may provide a solution to describing highly variable effort in recreational fisheries while also validating activity and catch.

1. A robust scientific conclusion is the result of a rigorous scientific process. In observational ecology, this process involves making inferences about a population from a sample. The sample is crucial, and is the result of implementing a survey design. A good survey design ensures that the data from the survey are capable of answering the research question. Better designs, such as spatially balanced designs, will also be as precise as possible given the constraints of the budget. 2. Many study areas will have previously sampled ‘legacy sites’ that already have accumulated a time series of observations. For estimating trent, it is often beneficial to include these sites within a new survey. In this paper, we propose a method to incorporate the locations of legacy sites into new spatially balanced survey designs to ensure spatial balance among all sample locations. 3. Simulation experiments indicate that incorporating the spatial location of legacy sites increases spatial balance and decreases uncertainty in inferences (smaller standard errors in mean estimates) when compared to designs that ignore legacy site locations. We illustrate the process of incorporating legacy sites using a proposed survey of a large marine reserve in South-Eastern Australia, although the method is applicable to all environments. 4. Our approach allows for integration of legacy sites into a new spatially balanced design, increasing efficiency. Scientists, managers and funders alike will benefit from this methodology – it provides a tool to provide efficient survey designs around established ones, including in-the-field adjustments. In this way, it can aid integrated monitoring programmes. An R-package that implements these methods, called MBHdesign, is available from CRAN.

Very high-resolution (VHR) satellite sensors can be used to estimate the size of animal populations, a critical factor in wildlife management, and acquire animal spatial distributions in an economical, easy, and precise way. We developed a method for satellite population size estimation that includes a noninvasive photogrammetry, from which the animal's average orthographic area is calculated, and an imagery interpretation method that estimates population size based on the ratio of an observed animal population area to the average individual area. As a proof of concept, we used this method to estimate the population size of Whooper Swans (Cygnus cygnus) in a national nature reserve in China. To reduce errors, the reserve was subdivided into regions of interest based on locations of Whooper Swan and background brightness. Estimates from the satellite pixels were compared with manual counts made over 2 years, at 3 locations, and in 3 land-cover types. Our results showed 1124 Whooper Swans occupied a national nature reserve on 15 February 2013, and the average percent error was 3.16% (SE = 1.37). These results demonstrate that our method produced robust data for population size estimation that were indistinguishable from manual count data. Our method may be used generally to estimate population sizes of visible and gregarious animals that exhibit high contrast relative to their environments and may inform estimations of populations in complex backgrounds.Estimación del Tamaño de las Poblaciones Animales Mediante Imágenes Satelitales de Muy Alta Resolución Resumen Los sensores satelitales de muy alta resolución (VHR) pueden utilizarse para estimar el tamaño de las poblaciones animales, un factor muy importante para el manejo de fauna, y para adquirir las distribuciones espaciales de los animales de una manera económica, sencilla y precisa. Desarrollamos un método para la estimación satelital del tamaño poblacional que incluye fotogrametría no invasiva, a partir de la cual se calcula el área ortogonal promedio del animal, y un método de interpretación de imágenes que estima el tamaño poblacional con base en la proporción del área poblacional observada de un animal con respecto al área individual promedio. Como demostración conceptual, usamos este método para estimar el tamaño poblacional del cisne trompetista (Cygnus cygnus) dentro de una reserva natural nacional en China. Para reducir los errores, subdividimos la reserva en regiones de interés con base en las ubicaciones de los cisnes y el brillo del fondo. Las estimaciones a partir de los pixeles satelitales fueron comparadas con los conteos manuales realizados a lo largo de dos años en tres ubicaciones y en tres tipos de cobertura de suelo. Nuestros resultados mostraron a 1124 cisnes ocupando una reserva natural nacional el 15 de febrero de 2013 y el error porcentual promedio fue de 3.15% (SE 1.37). Estos resultados demostraron que nuestro método produjo datos sólidos para la estimación del tamaño poblacional que eran indistinguibles de los datos obtenidos mediante el conteo manual. Nuestro método puede usarse de manera generalizada para estimar el tamaño poblacional de especies gregarias y visibles que exhiben un contraste alto en relación con su entorno y puede orientar las estimaciones de poblaciones con fondos complejos.甚高分辨率 (VHR) 卫星传感器可以经济、便捷和准确的方式获得对野生动物管理至关重要的种群规模和空间分布信息。我们提出了一种使用卫星估算动物种群的方法, 该方法包括计算动物平均正射面积的非侵入式摄影方法, 以及从观测动物种群面积与平均个体面积比例估算动物种群规模的影像解译方法, 作为概念验证, 我们使用该方法估算了中国一个国家级自然保护区中大天鹅 (Cygnus cygnus) 的种群规模. 为了减少误差, 根据大天鹅分布和背景亮度该保护区被划分为多个感兴趣区域。我们对2期影像中3个地点和3种土地覆盖类型的卫星影像估算结果与目视计数进行了比较。结果表明 2013 年2月15日该国家级自然保护区内共有 1124 只大天鹅, 该方法的平均百分误差为 3.16% (SE 1.37) 。上述结果表明该方法为目视计数无法区分的动物提供可靠的种群规模数据。该方法总体上可用于估算可见的、聚集分布并与环境呈现高度反差的动物种群规模, 并为估算复杂背景下动物种群规模提供了思路.

Marine species live out-of-sight, consequently geographic range, population size and long-term trends are extremely difficult to characterise for accurate conservation status assessments. Detection challenges have precluded listing of marine bony fishes as Extinct on the International Union for Conservation of Nature (IUCN) Red List, until now (March 2020). Our data compilation on handfishes (Family Brachionichthyidae) revealed them as the most threatened marine bony fish family, with 7 of 14 species recently listed as Critically Endangered or Endangered. The family also includes the only exclusively marine bony fish to be recognised as Extinct – the Smooth handfish (Sympterichthys unipennis). Ironically, some of the characteristics that threaten handfishes with extinction have assisted assessments. Poor dispersal capabilities leading to small, fragmented populations allow monitoring and population size estimation for some shallow water species. Evidence that the Smooth handfish is now Extinct included no sightings over 200 years in an area subject to numerous scientific surveys, inferred shallow habitat and moderate abundance at time of original collection, and major habitat transformation through fishing, aquaculture, rising sea temperature, and urban development. Contemporary threats to extant handfish species include habitat degradation, introduced species, loss of spawning substrate, climate change, and demographic risks associated with small, fragmented populations. Multifaceted conservation efforts are needed, including addressing threats to habitat quality, bolstering wild population numbers, and implementing novel techniques to find and monitor populations. Expanded monitoring, including application of eDNA methods, represent critical steps towards overcoming the challenges in studying wild populations of rare marine species. Ongoing investigation will likely reveal numerous other threatened species for which little is known.

Successful marine management relies on understanding patterns of human use. However, obtaining data can be difficult and expensive given the widespread and variable nature of activities conducted. Remote camera systems are increasingly used to overcome cost limitations of conventional labour‐intensive methods. Still, most systems face trade‐offs between the spatial extent and resolution over which data are obtained, limiting their application. We trialed a novel methodology, CSIRO Ruggedized Autonomous Gigapixel System (CRAGS), for time series of high‐resolution photo‐mosaic (HRPM) imagery to estimate fine‐scale metrics of human activity at an artificial reef located 1.3 km from shore. We compared estimates obtained using the novel system to those produced with a web camera that concurrently monitored the site. We evaluated the effect of day type (weekday/weekend) and time of day on each of the systems and compared to estimates obtained from binocular observations. In general, both systems delivered similar estimates for the number of boats observed and to those obtained by binocular counts; these results were also unaffected by the type of day (weekend vs. weekday). CRAGS was able to determine additional information about the user type and party size that was not possible with the lower resolution webcam system. However, there was an effect of time of day as CRAGS suffered from poor image quality in early morning conditions as a result of fixed camera settings. Our field study provides proof of concept of use of this new cost‐effective monitoring tool for the remote collection of high‐resolution large‐extent data on patterns of human use at high temporal frequency.

Spotted handfish are a critically endangered anglerfish. Monitoring of the species has, in the past, been undertaken via underwater visual census (UVC) parameterised with fixed length 100 m × 3 m strip transects measured with reel lines. However, the sparse distribution and cryptic nature of handfish resulted in low statistical power to track populations through time. To achieve reasonable confidence of detecting change ~ 40 transects are required for density estimates, making the logistical constraints of monitoring onerous. We trialled a new survey method for UVC at one study site with a known local population of fish, replacing reel transects with variable length strip transects parameterised with a diver towed Global Positioning System (GPS) float. From 18 transects we determined a density of 24 (± 3.5) handfish per hectare, but bootstrapping suggested little improvement in precision occurred after 8 transects. Modelling these results to previous estimates at the site indicated that our GPS float approach required many fewer transects and dives to determine 50% increases or decreases in fish densities. This improvement was partly due to the better sampling efficiency; with 3 times the average search area per transect but was also a result of longer transects being a better solution for monitoring a sparse population. Our results returned a normal sample distribution of fish counts with few zeros and many multiple observations, which differed to the original approach which was heavily skewed towards zero observations per transect. However, at very low population densities even this more robust solution will require many samples to detect change. Our GPS parameterized surveys also improved the functionality of observing fish behaviour as we could accurately plot fish allowing for detailed investigation of distributions. When fish were observed they were also bi-laterally digitally photographed to record their unique natural markings. By synchronising the photographs timestamp with the GPS clock, we were able to geo-locate individual recaptures and our preliminary results suggests net movements were limited. This new approach increases the logistical feasibility for monitoring spotted handfish and may have applications for other sparsely distributed benthic species.

1.Obtaining accurate and representative demographic metrics for animal populations is critical to many aspects of wildlife monitoring and management. However, at remote animal colonies, metrics derived from sequential counts or other continuous monitoring are often subject to logistical, weather and disturbance challenges. The development of remote camera technologies has assisted monitoring, but limitations in spatial and temporal resolution and sample sizes remain. 2.Here, we describe the application of a robotic camera system (Gigapan) which takes a tiled sequence of photographs that are automatically stitched together to form high-resolution panoramas. We demonstrate the application of the Gigapan using data collected during field testing at a shy albatross colony on Albatross Island in northwest Tasmania. 3.We took daily panoramas over 5 days to estimate mean incubation shift duration, an indirect measure for foraging trip duration, in an existing study area. Similar numbers of occupied nests could be observed at a distance of approximately 100 m in the Gigapan panoramas compared to ground-based counts (115 and 117, respectively). Of these, birds on 90% of nests visible in the panoramas could be unambiguously identified as marked or unmarked with a small daub of paint throughout the study period and thus a shift change reliably recorded. Gigapan-based shift duration was estimated using a novel instantaneous statistical method and were longer than estimates earlier in the egg brooding period, potentially revealing a new pattern in shift duration. 4.This example field application provides proof of concept and demonstration that the relatively low-cost Gigapan system provides the spatial advantages of aerial photos with the detail and temporal replication of land-based camera systems. The Gigapan system can extend or enhance traditional data collection methods, particularly for simultaneous observations at distance, of the behaviour of surface nesting colonial seabirds.

Baited remote underwater video stations (BRUVS) are increasingly being used to examine assemblages of fishes, yet critical methodological questions related to sampling limitations and bias, such as the influence of bait type, remain poorly understood. At multiple locations, we examined the hypothesis that diversity and abundance in temperate reef fish assemblages were independent of bait type. We used 3 bait types (abalone viscera, pilchards and crushed urchin) and quantified commonly used metrics for the fish assemblage, including species richness, time of first arrival and relative abundance on 3 shallow rocky reefs in southeastern Australia over 2 yr. We distinguished the following 6 feeding guilds: herbivore, zooplanktivore, alga/ invertebrate consumers, invertebrate carnivore, macroinvertebrate carnivore and generalist carnivore. The response of fishes was dependent on bait type, with urchin bait performing particularly poorly. Although we did not detect statistical differences between the performance of pilchards and abalone viscera as bait, pilchards produced more consistent outcomes. Importantly, we also observed strong spatial effects. In general, bait type had a marked effect on species richness, but little influence on relative abundance. Overall we conclude that oily bait such as pilchards, which have been widely used in most studies, yield the most consistent outcomes. Consequently, bait type and spatial variation in fish assemblages needs to be considered in sampling designs to assess the limitations of BRUVS.

Baited remote underwater video stations (BRUVS) were used to examine variation in assemblages of reef fishes at scales of 100s of kilometres (between 3 marine parks in New South Wales, Australia) and kilometres (between 4 sites within each park). Temporal variation over 5 yr was also examined in 1 park (Solitary Islands). BRUVS were able to sample the relative abundance and distribution of species from a wide range of trophic groups, and were particularly effective for detect- ing cryptic predators. Significant variability in the fish assemblages occurred between each park con- sistent with the latitudinal distribution of the parks. Fish assemblages also varied significantly between sites within each park. Contrary to expectations, total species richness did not follow the expected latitudinal gradient. However, observed geographical patterns in species richness of certain families such as Labridae (greater richness in the most northern park) and Monacanthidae (greater species richness in southern parks) followed expectations. Abundant schooling species, common to all 3 parks, were important contributors to variation between sites. Temporal variation over 5 yr at 1 park was relatively minor compared to the spatial variation among the 3 parks. This suggests large- scale spatial separation is more important for structuring fish assemblages than time. A network of marine parks will therefore be required to represent variation in reef fish assemblages over this latitudinal scale.

We used a novel mid-water baited remote underwater video (BRUV) technique to sur- vey pelagic and mid-water fish assemblages at Lord Howe Island Marine Park, off eastern Australia (31.5° S, 159.1° E). We found differences in assemblages among regions separated on a scale of ~10s of kilometres. Of the environmental variables measured in the present study (depth, temperature, water current speed), current speed had the greatest influence on the structure of pelagic assem- blages. Carcharhinus galapagensis, Seriola rivoliana and Scomber australasicus had similar distribu- tions and were associated with low flow environments. Seriola lalandi was associated with the higher flow environments sampled during our surveys, although current speeds in the sample area were rel- atively slow (0.03 to 0.34 m s -1 ; mean 0.17 m s -1 ). Relationships between pelagic assemblages and current speed were detected when abundances were calculated using an area-based approximation for plume dispersal, but were not detected using a linear approximation, or when current was assumed constant across all BRUV deployments. Our results demonstrate the difficulty in separating the dual effects of current speed in BRUV studies: the effect of current on bait plume size and associ- ated estimates of fish abundance, and the role of current as an aspect of preferred pelagic fish habi- tat. We recommend the use of area-based approximations of plume dispersal and the inclusion of accurate estimates of current speed as a statistical covariate when interpreting mid-water BRUV data. Our results indicate that oceanographic characteristics can be important for pelagic fish habitat selection over the scale of kilometres and should be considered during marine protected area zoning.

Planners of Marine Protected Areas (MPAs) commonly use maps of habitat types when choosing areas to conserve. This assumes that habitats are homogeneous, and therefore, that any area of habitat will represent the full spectrum of ecological diversity within that habitat. Here, we report that macrobenthic assemblages in tidal flat habitats were spatially heterogeneous in terms of beta diversity (taxonomic turnover), abundance, taxonomic richness and Shannon–Wiener H′ Diversity. Importantly, the patterns of heterogeneity were scale dependent for the three spatial scales we examined; plots (20 m), sites (100s of m) and estuaries (

Powerboats are potentially a significant source of disturbance to coastal cetaceans. Information is scarce, however, on the nature of interactions between powerboats and dolphins, particularly when both surface and acoustic behaviour are combined. The surface behaviour and acoustic response of travelling dolphins to approaches by a powerboat were assessed by a series of experimental trials between November 2001 and November 2003 in Jervis Bay, New South Wales, Australia. Dolphin behaviour was monitored continuously from an independent research boat before, during and after a powerboat approached ( n = 12). Treatments were interspersed with control observations ( n = 12). Changes in surface behaviour indicated differences between the treatment and control periods ( z = 2.24, p = 0.025), with dolphins tending to alter their surface behaviour when exposed to the powerboat approach. Analysis also revealed a change in the direction of travel by dolphin groups when approached ( z = 3.22, p = 0.001). Changes in surface behaviour occurred at vessel approach distances outside the minimum approach distance of 30 m for recreational and commercial vessels, as proposed by the New South Wales National Parks and Wildlife Service. In contrast, there were no changes in dolphin whistle rates ( F 3,12 = 0.74, p = 0.54) or the duration of echolocation click bouts ( F 3,12 = 0.76, p = 0.59) when approached. These findings indicate that powerboats do affect the surface behaviour and direction of travelling inshore bottlenose dolphins in Jervis Bay; however it appears that this impact is not reflected in their acoustic behaviour.

Between 2001 and 2003, we undertook 137 boat surveys for White-bellied Sea-Eagles, to investigate the abundance and distribution in Jervis Bay, New South Wales, Australia. Adult sighting rates differed between years, being highest in 2003, and both adult and sub-adult Sea-Eagle numbers differed between seasons. High sighting rates of sub-adults each autumn (April) were thought to reflect not only the appearance of locally fledged juveniles but also an influx of immature birds (2–4 years old) from outside the study area. Although it was common to observe single adult birds and pairs throughout the year, influxes of sub-adults in autumn generally led to an increase in observed group size. The largest group of Sea-Eagles observed contained eight individuals and most groups larger than two contained both adults and sub-adults. Observability was related to age-class and behaviour, with perching behaviour common in adults but relatively rare for sub-adults. The density of Sea-Eagles, and sub-adults in particular, was highest on the undeveloped northern and southern headlands, which are military and conservation reserves, compared with the urban settlements on the western shore of the study area. Furthermore, Sea-Eagles were only observed perching in forest reserves interspersed between urbanised areas, despite the appearance of suitable perches throughout the coastal suburbs. In view of these results, we discuss the possible implications for management of Sea-Eagle habitat.

(2008). SHORT-TERM BEHAVIOURAL RESPONSE OF BOTTLENOSE DOLPHINS TURSIOPS ADUNCUS TO RECREATIONAL POWERBOATS. Bioacoustics: Vol. 17, No. 1-3, pp. 171-173.

Theoretical models of marine protected areas (MPAs) that explore benefits to fisheries or biodiversity conservation often assume a dynamic pool of fishing effort. For instance, effort is homogenously distributed over areas from which subsets of reserves are chosen. I tested this and other model assumptions with a case study of the multiple-use Jervis Bay Marine Park. Prior to zoning of the park I conducted 166 surveys of the park's recreational fisheries, plotting the location of 16,009 anglers. I converted these plots into diagrams of fishing effort and analyzed correlates between fishing and habitat and the effect of two reserve designs—the draft and final zoning plans of the park—on the 15 fisheries observed. Fisheries were strongly correlated with particular habitats and had negatively skewed and often bimodal spatial distribution. The second mode of intensely fished habitat could be 6 SD greater than the fishery's mean allocation of effort by area. In the draft-zoning plan, sanctuary zone (no-take) area and potential subduction of fishing effort were similar. In the final plan, which was altered in response to public comment, the area of sanctuary zone increased, and the impact on fishing effort decreased. In only one case was a fishery's most intensely targeted location closed to fishing. Because of the discriminating manner with which fishers target habitats, if simple percentage targets are used for planning, sanctuary location can be adjusted to avoid existing fishing effort. According to modeled outcomes, the implication of this may be diminished reserve effectiveness. To address this, reserve area should be implicitly linked to subducted fishing effort when promoting or modeling MPAs.