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Utilization of marine photovoltaic energy is primarily focused on surface harvesting with limited photovoltaic cell implementations in submarine environments. Potential applications include marine wildlife telemetry devices, autonomous underwater vehicles, or remote sensing assets. In these applications, understanding the power at depth is critical, but there has yet to be a long‐term study of cell performance in a realistic marine environment that spans time, geographic location, and depth. In this paper, we present photovoltaic assessments carried out by devices mounted to adult female northern elephant seals (Mirounga angustirostris) during their spring migrations in the Pacific Ocean with deployment times between 76 and 107 days. Encompassing a large geographic area between Santa Cruz, California, and the Aleutian Islands of Alaska during their migrations, elephant seal behavior allows for repeated depth profiles each day, making them an ideal host for subsurface power assessments. This paper presents the first longitudinal study of photovoltaic cell performance in the marine environment that spans location, time, and depth. This work discusses the calibration, data time alignment, and power calculations of these oceanic deployments. Deployment results, including power results and energy predictions from the data record, are presented up to 22 m in depth. We highlight how the recorded power data of these cells compares to previously published results and how depth impacts subsurface power and energy harvesting. [ABSTRACT FROM AUTHOR]

Although sea turtles are well-studied charismatic marine species, little is known about the juvenile stage, especially the oceanic phase between hatching on their natal beaches and their adult lives. To collect data on these “lost years,” six juvenile green turtles were equipped with satellite tags, released from southwestern Dominica in the eastern Caribbean, and tracked for up to 3 months. Mapping turtle movement to ocean currents reveals that juvenile green turtles spent most of their travel time within the Caribbean Sea, passively riding the prevailing currents before actively directing themselves toward distant coastal waters. Half of the tagged turtles traveled to coastal foraging grounds off of Colombia and Venezuela, while one traveled north past Puerto Rico. These findings provide novel data for the movements of juvenile green turtles hatched in the Eastern Caribbean region.

Telemetry is an increasingly common tool for studying the ecology of wild fish, with great potential to provide valuable information for management and conservation. For researchers to conduct a robust telemetry study, many essential considerations exist related to selecting the appropriate tag type, fish capture and tagging methods, tracking protocol, data processing and analyses, and interpretation of findings. For telemetry-derived knowledge to be relevant to managers and policy makers, the research approach must consider management information needs for decision-making, while end users require an understanding of telemetry technology (capabilities and limitations), its application to fisheries research and monitoring (study design), and proper interpretation of results and conclusions (considering the potential for biases and proper recognition of associated uncertainties). To help bridge this gap, we provide a set of considerations and a checklist for researchers to guide them in conducting reliable and management-relevant telemetry studies, and for managers to evaluate the reliability and relevance of telemetry studies so as to better integrate findings into management plans. These considerations include implicit assumptions, technical limitations, ethical and biological realities, analytical merits, and the relevance of study findings to decision-making processes. [ABSTRACT FROM AUTHOR]

Highlights • Acoustic-tagging protocol for twaite shad was incrementally refined. • All captured shad survived handling, anaesthesia (i.e. MS-222) and tagging. • Surgically implantation was significantly faster than externally mounting the tag. • Movement distance and speed were similar for externally and internally tagged fish. • Internal tagging under anaesthesia is recommended for studying shad migration. Abstract Telemetry investigations to gather essential information about fish migrations are reliant on the behaviour, condition and survival of the animals being unaltered by the tagging procedure. Twaite shad (Alosa fallax Lacépède; 'shad') is a threatened clupeid fish for which there is a considerable knowledge gap on their anadromous movements. They are also reported to be sensitive to handling and anaesthesia, resulting in practical difficulties in tag implantation; previous investigations externally attached tags without sedation. The aim of this study was to incrementally refine the acoustic-tagging protocol for shad via application of a previously un-tried anaesthetic (i.e. tricaine methanesulphonate (MS-222)) and by surgical implantation of the tag in the peritoneal cavity. All captured shad (n = 25) survived handling, anaesthesia and tagging, and were detected moving upstream after release. Surgically implantation (n = 5) was significantly faster than externally mounting the tag (n = 20) and time to recover was similar. Total upstream movement, total movement, residence time in receiver array and speed of upstream movement were statistically similar for externally and internally tagged fish. Post-spawning, a large proportion (68%) of tagged fish returned to the estuary, downstream of the receiver array. Internal tagging under anaesthesia is recommended for studying anadromous movements of shad, given welfare benefits during surgery and once at liberty, thus increasing the likelihood of tagged fish performing natural behaviours. Further, implantation of tags programmed to last many years enables multiple spawning migrations by the same individuals to be studied, which would lead to substantial advances in ecological knowledge and potentially reduce the number of fish tagged. [ABSTRACT FROM AUTHOR]

Little is known about the behavior and migration of deep-sea snappers, as observation of their deep-sea habitats is difficult. Manual acoustic tracking of deepwater longtail red snappers Etelis coruscans was conducted at the Ojika Se Bank, in the waters around the Satsunan Islands, Japan, to investigate their post-release horizontal and vertical behavior. Eight individuals were tagged with transmitters equipped with depth sensors for tracking. At least six of these eight fish survived after release. The fish gradually dispersed from the Ojika Se Bank, and only one-third remained there 33-34 days after release. The fish that remained at the Ojika Se Bank moved horizontally by 2.2 ± 2.0 km daily, but remained near the top of the bank. The fish were distributed in the 168.8- to 288.8-m depth range, and moved vertically by up to 50.0 m between consecutive days. To the best of our knowledge, this is the first report on the daily fine-scale horizontal and vertical movements of any species of deep-sea snapper. [ABSTRACT FROM AUTHOR]

Aim: Climate change is altering marine ecosystems worldwide and is most pronounced in the Arctic. Economic development is increasing leading to more disturbances and pressures on Arctic wildlife. Identifying areas that support higher levels of predator abundance and biodiversity is important for the implementation of targeted conservation measures across the Arctic. Location: Primarily Canadian Arctic marine waters but also parts of the United States, Greenland and Russia. Methods: We compiled the largest data set of existing telemetry data for marine predators in the North American Arctic consisting of 1,283 individuals from 21 species. Data were arranged into four species groups: (a) cetaceans and pinnipeds, (b) polar bears Ursus maritimus (c) seabirds, and (d) fishes to address the following objectives: (a) to identify abundance hotspots for each species group in the summer–autumn and winter–spring; (b) to identify species diversity hotspots across all species groups and extent of overlap with exclusive economic zones; and (c) to perform a gap analysis that assesses amount of overlap between species diversity hotspots with existing protected areas. Results: Abundance and species diversity hotpots during summer–autumn and winter–spring were identified in Baffin Bay, Davis Strait, Hudson Bay, Hudson Strait, Amundsen Gulf, and the Beaufort, Chukchi and Bering seas both within and across species groups. Abundance and species diversity hotpots occurred within the continental slope in summer–autumn and offshore in areas of moving pack ice in winter–spring. Gap analysis revealed that the current level of conservation protection that overlaps species diversity hotspots is low covering only 5% (77,498 km2) in summer–autumn and 7% (83,202 km2) in winter–spring. Main conclusions: We identified several areas of potential importance for Arctic marine predators that could provide policymakers with a starting point for conservation measures given the multitude of threats facing the Arctic. These results are relevant to multilevel and multinational governance to protect this vulnerable ecosystem in our rapidly changing world. [ABSTRACT FROM AUTHOR]

To assess yellow eel (Anguilla anguilla L.) densities in non‐tidal waters, 1‐ha enclosure approach was developed. For unbiased density and biomass calculations, the catchability of the system needs to be evaluated. A telemetry study with 49 tagged eels was conducted in 2015 and 2016 to verify the effectiveness of the 1.8‐m high boundary net. Excluding recaptured eels (N = 10), 42.8% of the released eels (N = 15) escaped the enclosure within 48 hr. Regarding the movement frequency, similar movement patterns were observed for enclosed and escaped eels within 48 hr after release. Based on the telemetry study, it is concluded that the boundary net is recognised as an obstacle by yellow eels, and reduces the escapement of enclosed eels. [ABSTRACT FROM AUTHOR]

During 2013–2015, an outbreak of dolphin morbillivirus (DMV) occurred in the western North Atlantic, which resulted in the stranding of over 1,600 common bottlenose dolphins (Tursiops truncatus). There are currently five coastal and 10 bay, sound, and estuary dolphin stocks along the U.S. Atlantic coast, yet there is very limited understanding of which stocks were exposed to DMV during the recent outbreak, or how DMV was transmitted across stocks. In order to address these questions, information is needed on spatial overlap and stock interactions. The goals of this project were to determine ranging patterns, prevalence of DMV, and spatial overlap of the South Carolina‐Georgia (SC‐GA) Coastal Stock, and adjacent Southern Georgia Estuarine System (SGES) Stock. During September 2015, a health assessment and telemetry study was conducted in which 19 dolphins were captured, tested for antibodies to DMV, and satellite tagged. Dolphins were classified into one of three ranging patterns (Coastal, Sound, or Estuary) based upon telemetry data. Coastal dolphins (likely members of the SC‐GA Coastal Stock) had a significantly higher prevalence of positive DMV antibody titers (0.67; N = 2/3), than Sound and Estuary dolphins (likely members of the SGES Stock) (0.13; N = 2/16). These results suggest that the SC‐GA Coastal Stock may have experienced greater exposure to DMV as compared to the SGES Stock. However, due to the small size of the SGES Stock and its exposure to high levels of persistent contaminants, this stock may be particularly vulnerable to DMV infection in the future. During 2013–2015, an outbreak of dolphin morbillivirus (DMV) occurred in the western North Atlantic in which over 1,600 common bottlenose dolphins stranded. A health assessment and telemetry study was initiated to assess DMV prevalence and ranging patterns of dolphins along the Georgia coast. The results of this study suggest that spatial overlap between dolphin stocks may play a role in DMV exposure [ABSTRACT FROM AUTHOR]

Sea ice reduction in the Arctic is allowing for increased vessel traffic and activity. Vessel noise is a known anthropogenic disturbance, but its effects on Arctic fish are largely unknown. Using acoustic telemetry — Vemco positioning system — we quantified the home ranges and fine-scale movement types (MT) of shorthorn sculpin (Myoxocephalus scorpius), a common benthic Arctic fish, in response to vessels and environmental drivers during open water over 3 years (2012–2014). Low overlap of core home ranges (50%) for all years and a change of overall MT proportions (significant in 2012 only) were observed when vessels were present compared with absent. However, changes in MTs associated with vessel presence were not consistent between years. Photoperiod was the only environmental driver that influenced (R2 = 0.32) MTs of sculpin. This is the first study of vessel impacts on Arctic fish using acoustic telemetry and demonstrates that individuals alter their behavior and home ranges when vessels are present. Given increasing vessel traffic in the Arctic, additional study on the impact of vessels on these ecosystems is warranted. [ABSTRACT FROM AUTHOR]

The habits and habitats of pygmy killer whales (Feresa attenuata) in the Gulf of Mexico (GoM) are poorly known outside of strandings and line-transect surveys. Two adult male pygmy killer whales were found live-stranded in the state of Mississippi (USA) on 1 September 2015 and were subsequently rehabilitated and returned to the offshore waters of the GoM on 11 July 2016. To monitor the animals post-release, both were tagged with satellite-linked location and dive behavior tags. Tags were programed to record and transmit dive duration and depth (when dives were ≥ 30 m deep for ≥ 30 s), duration of time spent above 30 m depth, and estimate locations using the Argos system. The tags transmitted for 15 and 88 days, respectively, providing a total of 1,027 filtered locations and 3,150 dive duration and maximum depth records. The animals began diving after two and four days, respectively, post-release. More than 96% of dives occurred at night. The longest recorded dive was more than 9 min in duration, and the deepest was to 368 m. More than 98% of the locations were over the GoM shelf break, spanning water 200 to 1,200 m deep. Diving patterns indicate that this species is most active at night in the GoM, suggesting its prey species are likely diel migrators that are below reachable depths during daylight hours. Near simultaneous location data from both animals confirmed that they stayed in close proximity but did not dive synchronously. Success of the rehabilitation and release was inconclusive for pygmy killer whale ID 30IMMS, whereas 31IMMS met the established criteria for success with ≥ 6 weeks of documented post-release survival. Follow-up monitoring through satellite-linked telemetry provided not only important data for evaluating the success of the rehabilitation but also for documenting the activity and habitat use of these seldom-observed cetaceans. [ABSTRACT FROM AUTHOR]

Abstract We collated available satellite telemetry data for six species of ice-associated marine mammals in the Pacific Arctic: ringed seals (Pusa hispida ; n = 118), bearded seals (Erignathus barbatus, n = 51), spotted seals (Phoca largha, n = 72), Pacific walruses (Odobenus rosmarus divergens, n = 389); bowhead whales (Balaena mysticetus, n = 46), and five Arctic and sub-arctic stocks of beluga whales (Delphinapterus leucas, n = 103). We also included one seasonal resident, eastern North Pacific gray whales (Eschrichtius robustus, n = 12). This review summarized the distribution of daily locations from satellite-linked transmitters during two analysis periods, summer (May–November) and winter (December–April), and then examined the overlap among species. Six multi-species core use areas were identified during the summer period: 1) Chukotka/Bering Strait; 2) Norton Sound; 3) Kotzebue Sound; 4) the northeastern Chukchi Sea; 5) Mackenzie River Delta/Amundsen Gulf; and 6) Viscount Melville Sound. During the winter period, we identified four multi-species core use areas: 1) Anadyr Gulf/Strait; 2) central Bering Sea; 3) Nunivak Island; and 4) Bristol Bay. During the summer period, four of the six areas were centered on the greater Bering Strait region and the northwestern coast of Alaska and included most of the species we examined. The two remaining summer areas were in the western Canadian Arctic and were largely defined by the seasonal presence of Bering-Chukchi-Beaufort stock bowhead whales and Eastern Beaufort Sea stock beluga whales, whose distribution overlapped during both summer and winter periods. During the winter period, the main multi-species core use area was located near the Gulf of Anadyr and extended northwards through Anadyr and Bering Straits. This area is contained within the Bering Sea "green belt", an area of enhanced primary and secondary productivity in the Bering Sea. We also described available telemetry data and where they can be found as of 2017. These data are important for understanding ice-associated marine mammal movements and habitat use in the Pacific Arctic and should be archived, with appropriate metadata, to ensure they are available for future retrospective analyses. [ABSTRACT FROM AUTHOR]

Spatial separation within predator communities can arise via territoriality but also from competitive interactions among and within species. However, linking competitive interactions to predator distribution patterns is difficult and theoretical models predict different habitat selection patterns dependent on habitat quality and how competition manifests itself. While models generally consider competitors to be either equal in ability, or for one phenotype to have a fixed advantage over the other, few studies consider that an animal may only have a competitive advantage in specific habitats. We used  10 years of telemetry data, habitat surveys and behavioral experiments, to show spatial partitioning between and within two species of reef shark (grey reef Carcharhinus amblyrhinchos and blacktip reef sharks C. melanopterus) at an unfished Pacific atoll. Within a species, sharks remained within small ‘sub‐habitats’ with very few movements of individuals between sub‐habitats, which previous models have suggested could be caused by intra‐specific competition. Blacktip reef sharks were more broadly distributed across habitat types but a greater proportion used lagoon and backreef habitats, while grey reef sharks preferred forereef habitats. Grey reef sharks at a nearby atoll where blacktip reef sharks are absent, were distributed more broadly between habitat types than when both species were present. A series of individual‐based models predict that habitat separation would only arise if there are competitive interactions between species that are habitat‐specific, with grey reefs having a competitive advantage on the forereefs and blacktips in the lagoons and backreef. We provide compelling evidence that competition helps drive distribution patterns and spatial separation of a marine predator community, and highlight that competitive advantages may not be constant but rather dependent on habitats. [ABSTRACT FROM AUTHOR]

Aim: Climate change is fundamentally altering habitats, with complex consequences for species across the globe. The Arctic has warmed 2-3 times faster than the global average, and unprecedented sea ice loss can have multiple outcomes for ice-associated marine predators. Our goal was to assess impacts of sea ice loss on population-specific habitat and behaviour of a migratory Arctic cetacean. Location: Arctic Ocean. Methods: Using satellite telemetry data collected during summer-fall from sympatric beluga whale (Delphinapterus leucas) populations ("Chukchi" and "Beaufort" belugas), we applied generalized estimating equations to evaluate shifts in sea ice habitat associations and diving behaviour during two periods: 1993-2002 ("early") and 2004-2012 ("late"). We used resource selection functions to assess changes in sea ice selection as well as predict trends in habitat selection and "optimal" habitat, based on satellite-derived sea ice data from 1990 to 2014. Results: Sea ice cover declined substantially between periods, and Chukchi belugas specifically used significantly lower sea ice concentrations during the late than early period. Use of bathymetric features did not change between periods for either population. Population-specific sea ice selection, predicted habitat and the amount of optimal habitat also generally did not change during 1990-2014. Chukchi belugas tracked during 2007-2012 made significantly more long-duration and deeper dives than those tracked during 1998-2002. Main conclusions: Taken together, our results suggest bathymetric parameters are consistent predictors of summer-fall beluga habitat rather than selection for specific sea ice conditions during recent sea ice loss. Beluga whales were able to mediate habitat change despite their sea ice associations. However, trends towards prolonged and deeper diving possibly indicate shifting foraging opportunities associated with ecological changes that occur in concert with sea ice loss. Our results highlight that responses by some Arctic marine wildlife can be indirect and variable among populations, which could be included in predictions for the future. [ABSTRACT FROM AUTHOR]

The deep-sea is increasingly viewed as a lucrative environment for the growth of resource extraction industries. To date, our ability to study deep-sea species lags behind that of those inhabiting the photic zone limiting scientific data available for management. In particular, knowledge of horizontal movements is restricted to two locations; capture and recapture, with no temporal information on absolute animal locations between endpoints. To elucidate the horizontal movements of a large deep-sea fish, a novel tagging approach was adopted using the smallest available prototype satellite tag – the mark-report pop-up archival tag (mrPAT). Five Greenland sharks ( Somniosus microcephalus ) were equipped with multiple mrPATs as well as a standard archival satellite tag (miniPAT) that were programmed to release in sequence at 8–10 day intervals. The performance of the mrPATs was quantified. The tagging approach provided multiple locations per individual and revealed a previously unknown directed migration of Greenland sharks from the Canadian high Arctic to Northwest Greenland. All tags reported locations, however, the accuracy and time from expected release were variable among tags (average time to an accurate location from expected release = 30.8 h, range: 4.9–227.6 h). Average mrPAT drift rate estimated from best quality messages (LQ1,2,3) was 0.37 ± 0.09 m/s indicating tags were on average 41.1 ± 63.4 km (range: 6.5–303.1 km) from the location of the animal when they transmitted. mrPATs provided daily temperature values that were highly correlated among tags and with the miniPAT (70.8% of tag pairs were significant). In contrast, daily tilt sensor data were variable among tags on the same animal (12.5% of tag pairs were significant). Tracking large-scale movements of deep-sea fish has historically been limited by the remote environment they inhabit. The current study provides a new approach to document reliable coarse scale horizontal movements to understand migrations, stock structure and habitat use of large species. Opportunities to apply mrPATs to understand the movements of medium size fish, marine mammals and to validate retrospective movement modeling approaches based on archival data are presented. [ABSTRACT FROM AUTHOR]

Abstract: Animal‐borne instruments have become a standard tool for collecting important data from marine mammals. However, few studies have examined whether placement of these data loggers affects the behavior and energetics of individual animals, potentially leading to biasing data. We measured the effect of two types of relatively small data loggers (<1% of animals’ mass and front profile) on the swimming speeds and energy expenditure of four female northern fur seals (Callorhinus ursinus) while swimming at depth. Swim speeds and rates of oxygen consumption were measured as the trained fur seals repeatedly swam an underwater circuit, with or without the tags. We found the placement of either tested tag significantly affected both the behavior and energetics of the fur seals in our study. Diving metabolic rate increased an average of 8.1%–12.3% (depending on tag type) and swim speed decreased an average of 3.0%–6.0% when wearing the tags. The combined changes in velocities and metabolic rates resulted in a 12.0%–19.0% increase in the total energy required by the fur seals to swim a set distance. The demonstrated effects of tags on behavior and energy expenditure may bias data sets from wild animals and potentially incur longer‐term impacts on the studied animals. [ABSTRACT FROM AUTHOR]

Abstract: The population of Weddell seals (Leptonychotes weddellii) in the southern Weddell Sea is in a unique position on the continental shelf edge, with vast shelf waters to the south, and deep Southern Ocean to the north. We describe sex‐related differences in the winter distribution of this population, from data collected by 20 conductivity‐temperature‐depth satellite relay data loggers deployed in February 2011 at the end of the annual molt. The regional daily speed was calculated, and a state‐space model was used to estimate behavioral states to positions along individuals’ tracks. GLMMs estimated that males and smaller individuals, diving in shallower water, traveled less far per day of deployment (males 14.6 ± 2.26 km/d, females 18.9 ± 2.42 km/d), and males were estimated to dive in shallower water (males 604 ± 382 m, females 1,875 ± 1,458 m). Males and smaller individuals were also estimated to be more resident; males spent an average 83.4% ± 7.7% of their time in a resident behavioral state, compared to females at 74.1% ± 7.1%. This evidence that male and female Weddell seals in the southern Weddell Sea are adopting different strategies has not been shown elsewhere along their circumpolar distribution. [ABSTRACT FROM AUTHOR]

We hypothesized that the use of habitat by two armored catfish species, Ancistrus aff. cirrhosus and Hypostomus ancistroides, which share the same stream reach, is temporally segregated. To test this, fish residence time within a culvert and fish movements through the culvert were analyzed in relation to the daily hours, lunar cycle and discharge using Passive Integrated Transponder telemetry. The residence time for A. aff. cirrhosus conducting upstream movements was longer than H. ancistroides. Both species exhibited high nocturnal activity, although at different periods: A. aff. cirrhosus was most active at dawn (00:00-05:59 hr), while H. ancistroides exhibited intense activity at night (18:00-23:59 hr), indicating temporal segregation of movement behavior between species. In addition, A. aff. cirrhosus was most active in the new moon phase and when there was high water discharge, while H. ancistroides was most active only when there was high water discharge. This study elucidates the patterns of daily movement behavior and temporal habitat use of these fish species. [ABSTRACT FROM AUTHOR]

The article proposes a model of the system supporting the decision-making process relating to the radio operator on board a ship after a distress alert is received by a Digital Selective Calling (DSC) controller working on VHF channel 70. The model is aimed at the implementation into the system of radiocommunication event management. The system takes into account the existing Radio Regulations. The model makes use of Petri nets, which are elements of graph theory. The time domain is comprised in the developed graph, and the states (places) and transitions capable of autonomous functioning are separated, as are those places and transitions requiring direct operator action based on empirical knowledge. [ABSTRACT FROM AUTHOR]

Fishways are installed worldwide to facilitate accessibility to functional habitats and to increase the ecological continuity of rivers. Their evaluations are increasing, but complete studies in the field with wild individuals are still scarce. In the lower Bocq River (Belgium), a pool type fishway was installed in 2011. A combined passive-integrated-transponder-tag and radio-telemetry system was designed and installed downstream of the dam and in the fishway to analyse fine-scale individual fish behaviour. Three fish species (brown trout, European grayling, and barbel) were captured in the river; n = 125 fish were tagged and released downstream of the fishway. Behavioural metrics were proposed and used in order to attain a comprehensive view on the efficiency of the fishway, including attraction and entrance efficiency, searching and passage delays, and overall and adjusted passage efficiency. The results indicate a major problem in terms of attraction efficiency (48.9% for the trout, 20.5% for the grayling, and 41.2% for the barbel) and time to find the entrance of the fishway (mean 65.1 hr for the trout and 538.9 hr for the grayling). For fish that succeed to approach the entrance of the fishway, the passage efficiency was 86.9% for the trout, 55.5% for the grayling, and 7.1% for the barbel. The time taken to cross the structure was reasonable for the salmonids (mean < 1.5 hr for trout and grayling) but very long (21 hr) for the barbel. Our results underline the necessity of a holistic approach to evaluate fishway efficiency using precise comprehensive metrics and hydraulic characterization. [ABSTRACT FROM AUTHOR]

The ocean migration of 16 post-spawned adult Atlantic salmon [Salmo salar L.] from the Miramichi River, Canada, tagged concurrently with pop-up satellite archival tags and acoustic transmitters was reconstructed using a Hidden Markov Model. Individuals exclusively utilized areas within the Gulf of St Lawrence and the Labrador Sea, and showed little overlap with known distributions of European stocks. During the migration, individuals were generally associated with surface waters and spent >67% of the time in the upper 10 m of the water column. The Atlantic salmon occupied greater depths and showed more diving activity during the day than during the night, with a few exceptions. Although residing in the Gulf of St Lawrence, individuals used different geographical areas and displayed frequent dives to shallow depths (10–30 m). All fish that entered the Labrador Sea (n¼8) migrated through the Strait of Belle Isle (767 km from the river mouth), after spending 41–60 d in the Gulf of St Lawrence. After exiting the Gulf of St Lawrence, individuals utilized different areas in the Labrador Sea, and overlaps in spatial distributions among the individuals were largely limited to the Labrador Coast. This variation in area use was accompanied by individual differences in diving behaviour, with maximum depths recorded for individuals ranging from 32 to 909 m. Dives to depths exceeding 150 m were only performed by four individuals and mainly restricted to the central Labrador Sea (areas with water depths >1000 m). Vertical movements were shallower and resembled those in the Gulf of St Lawrence when fish migrated through shallower coastal areas along the Labrador Shelf. In conclusion, the large overall variation in migration routes suggests that post-spawners from the Miramichi River encounter different habitats during their ocean migration and that the growth and survival of adults may depend on ecological conditions in multiple regions, both in the Gulf of St Lawrence and in the Labrador Sea. [ABSTRACT FROM AUTHOR]

The hypothesis that striped bass (Morone saxatilis), bluefish (Pomatomus saltatrix), weakfish (Cynoscion regalis), and species of forage fish would be associated closely with a salinity transition front was tested through sampling and tagging efforts. In a small New Jersey estuary, a station at a salinity front and another in a nearby channel were sampled weekly with gill nets. Abundance of bluefish was significantly greater at the front, and abundance of weakfish was significantly greater at the channel. Forage fish were collected at both stations, and the diets of bluefish and weakfish overlapped in all seasons. Ultrasonically tagged striped bass, weakfish, and bluefish were tracked concurrently, and their home ranges, or the 95% probability of their occurrences were computed. Home ranges of tagged striped bass occurred upriver and also near river kilometer 1. Home ranges of weakfish were located in the midriver channels, and those of bluefish were located midriver and upriver at river kilometers 5-12. Home ranges for these 3 species were not limited to the area of the salinity front, contrary to the initial hypothesis. [ABSTRACT FROM AUTHOR]

Underwater acoustic tag telemetry was used to assess behavioural differences between juvenile wild-type ( i.e. non-transgenic, NT) and growth hormone ( GH) transgenic (T) coho salmon Oncorhynchus kisutch in a contained simulated ocean environment. T O. kisutch were found across days to maintain higher baseline swimming speeds than NT O. kisutch and differences in response to feeding were detected between T and NT genotypes. This is the first study to assess behaviour of GH transgenic salmonids in a marine environment and has relevance for assessing whether behavioural effects of GH overexpression seen in freshwater environments can be extrapolated to oceanic phases of the life cycle. [ABSTRACT FROM AUTHOR]

The potential for populations to undergo adaptive evolution depends on individual variation in traits under selection and how multiple traits are correlated. While fitness relates to the performance of animals in the wild, most of the research on evolutionary potential of behavioural traits has used captive or mesocosm settings, especially with aquatic organisms. We investigated the individual level consistency (personalities) and correlations (behavioural syndromes) of fitness-related behavioural traits displayed by a harvested marine fish in the natural environment, and the potential of such individual level behaviour to constrain adaptive evolution. For this, we acoustically tracked 303 individuals of Atlantic cod, Gadus morhua , over a period of 3 years from two populations in southern Norway. We then estimated repeatability and correlations between four behavioural traits: diel vertical migration, activity, home range and dispersal. Average autonomy was estimated as a measure of the potential of the observed behavioural syndromes to constrain evolution. We found a moderate to high individual consistency in all behavioural traits (mean repeatability 0.41, range 0.22–0.66) suggesting that they reflect fish personalities. Also, behavioural traits were structured into behavioural syndromes, where one population displayed a more integrated behavioural syndrome (all the four traits correlated) than the other (only home range and dispersal correlated). In both populations, the magnitude of these behavioural syndromes could potentially constrain evolution, as revealed by average autonomy values significantly below 1. Our study provides strong empirical support to the idea that natural and human-induced selection on behavioural traits can indeed drive adaptive evolution, and, further, that such evolutionary responses may be constrained by the correlational structure among multiple traits. [ABSTRACT FROM AUTHOR]

Reef predators play a critical role in maintaining the balance of marine ecosystems and are an important component of Hawaii's recreational and commercial fisheries. In response to the increasing anthropogenic demands on these populations across the main Hawaiian Islands, the study of predator movements in marine protected areas has become a research priority. To this aim, we used passive acoustic telemetry to investigate the spatial and temporal movement patterns of five reef predator species: bluefin trevally ( Caranx melampygus), giant trevally ( Caranx ignobilis), green jobfish ( Aprion virescens), whitetip reef sharks ( Triaenodon obesus) and gray reef sharks ( Carcharhinus amblyrhynchos) at the 31 ha Molokini Marine Life Conservation District (MLCD) off Maui, Hawaii (Lat: 20°37′56.70″N, Lon: 156°29′44.52″W) from November 13, 2013 to August 28, 2015. Our results indicate that the predator assemblage in the MLCD was dominated by teleost fishes during the day and sharks at night. Residency was variable across species, with bluefin trevally exhibiting the highest residency in the MLCD, green jobfish the lowest, and long-distance movements between the Molokini MLCD and the other islands of the Maui Nui Complex were common for gray reef sharks and giant trevally. These results indicate that despite its small size, the Molokini MLCD provides a high level of protection to resident species such as bluefin trevally. However, this MLCD is less effective at protecting more mobile predators such as green jobfish, gray reef sharks and giant trevally. [ABSTRACT FROM AUTHOR]

This paper presents a review of inspection-class Remotely Operated Vehicles (ROVs). The review divides the classification of inspection-class ROVs; categorising the vehicles in order of size and capability. A state of the art technology review is undertaken, discussing various common subsystems of the ROV. Standard and novel ROV shapes and designs are reviewed, with emphasis on buoyancy, frame materials and hydrodynamics. Several power considerations and designs are discussed, accounting for battery fed and mains fed systems. ROV telemetry is split into a discussion on the various transmission hardware systems and the communication protocols that are most widely used in industry and research today. A range of thruster technologies is then introduced with consideration taken of the various thruster architectures available. Finally, the navigation and positioning sensors employed for ROV navigation and control are reviewed. The author has also created a number of comparison tables throughout the review; tables include comparison of wired data transmission technology, comparison of common ROV communication protocols and comparisons of various inertial navigation systems. By the end of the review the reader will have clearer understanding on the fundamentals of inspection-class ROV technologies and can use this as an introduction to further paper investigation. [ABSTRACT FROM AUTHOR]

Waterbird survival rates are a key component of demographic modeling used for effective conservation of long-lived threatened species. The Swan Goose (Anser cygnoides) is globally threatened and the most vulnerable goose species endemic to East Asia due to its small and rapidly declining population. To address a current knowledge gap in demographic parameters of the Swan Goose, available datasets were compiled from neck-collar resighting and telemetry studies, and two different models were used to estimate their survival rates. Results of a mark-resighting model using 15 years of neck-collar data (2001-2015) provided age-dependent survival rates and season-dependent encounter rates with a constant neck-collar retention rate. Annual survival rate was 0.638 (95% Cl: 0.378-0.803) for adults and 0.122 (95% Cl: 0.028-0.286) for first-year juveniles. Known-fate models were applied to the single season of telemetry data (autumn 2014) and estimated a mean annual survival rate of 0.408 (95% Cl: 0.152-0.670) with higher but non-significant differences for adults (0.477) vs. juveniles (0.306). Our findings indicate that Swan Goose survival rates are comparable to the lowest rates reported for European or North American goose species. Poor survival may be a key demographic parameter contributing to their declining trend. Quantitative threat assessments and associated conservation measures, such as restricting hunting, may be a key step to mitigate for their low survival rates and maintain or enhance their population. [ABSTRACT FROM AUTHOR]

Individual interactions are crucial to many ecological processes but are difficult to quantify for long periods in aquatic animals. In this study, we applied a digital proximity logging device recently developed for terrestrial animals to a freshwater fish, the brown trout ( Salmo trutta L.). After preliminary calibration and quantification of detection errors, we recorded the interactions occurring between five male and four female brown trout in an artificial channel during one week of the spawning season. The 55,637 logs recorded allowed us to describe the encounter network and its fine scale evolution. In particular, the time spent with females varied a lot across males, from two to 24 h in a five-day period, and the males, which spent the most time with females tended to mate more. At the individual level, the temporal distribution of encounters reflected shifts in dominance status, with males sequentially taking over exclusive proximity with females before spawning. Beyond sexual encounters, the method presented here could be applied to many processes interesting to fish ecologists, such as predator-prey interactions, intra and interspecific competition or disease transmission. [ABSTRACT FROM AUTHOR]

Recent evidence supports the existence of a downstream autumn-migratory phenotype in juvenile anadromous brown trout ( Salmo trutta), however the precise timing, extent and ecological significance of such behaviour remains ambiguous. We investigated the phenology of downstream migration of wild juvenile trout using passive integrated transponder (PIT) telemetry over an eight-month period in two European rivers; the River Deerness, north-east England, and the River Villestrup, Denmark. The incidence of autumn-winter seaward migration was greater in the Deerness than the Villestrup, with at least 46% of migrating juveniles detected prior to spring smoltification in the Deerness. Timing of migration was strongly regulated by factors associated with river discharge in both systems. While autumn and spring downstream migrants did not differ in size at the time of tagging in either system, evidence that spring migrants were of better condition, travelled faster (autumn: 11.0 km day; spring: 24.3 km day) and were more likely to leave the Deerness suggests that autumn and spring migrant conspecifics respond to different behavioural motivations. Further investigation into the sex of autumn migrant juveniles, as well as the temporal and geographical variability in the incidence and fitness consequences of autumn emigration by juvenile trout would be beneficial. [ABSTRACT FROM AUTHOR]

Marine telemetry expands the knowledge of the biology of marine species at risk: their life cycles, activities, interactions, habitats, and threats. Four seal species in Canada and Australia are faced with distinctive and divergent management problems. This article examines their conservation status, legal protection, and the role that telemetry has played, or could play, in providing previously unavailable information to help meet conservation goals. The value of telemetry data to minimize fisheries mortality of one species has been demonstrated in Australia. Despite there being significant telemetry data for the other species, policy and management have not yet responded. [ABSTRACT FROM AUTHOR]

Electronic telemetry is making major contributions to understanding the biology and the recovery of threatened and endangered aquatic species. A variety of electronic tag systems are available, with each type having it own strengths and weaknesses. Global networking and data sharing are becoming common, and are necessary to maximize benefits from investments in telemetry infrastructure. Future technology development will advance new sensors to document specific causes contributing to species declines (e.g., predation tags and camera tags). There is a need to expand the use of telemetry, especially in developing nations, to help guide sustainable use of the oceans. [ABSTRACT FROM AUTHOR]

As juvenile salmon enter the Sacramento-San Joaquin River Delta ("the Delta") they disperse among its complex channel network where they are subject to channel-specific processes that affect their rate of migration, vulnerability to predation, feeding success, growth rates, and ultimately, survival. In the decades before 2006, tools available to quantify growth, dispersal, and survival of juvenile salmon in this complex channel network were limited. Fortunately, thanks to technological advances such as acoustic telemetry and chemical and structural otolith analysis, much has been learned over the past decade about the role of the Delta in the life cycle of juvenile salmon. Here, we review new science between 2006 and 2016 that sheds light on how different life stages and runs of juvenile salmon grow, move, and survive in the complex channel network of the Delta. One of the most important advances during the past decade has been the widespread adoption of acoustic telemetry techniques. Use of telemetry has shed light on how survival varies among alternative migration routes and the proportion of fish that use each migration route. Chemical and structural analysis of otoliths has provided insights about when juveniles left their natal river, and provided evidence of extended rearing in the brackish or saltwater regions of the Delta. New advancements in genetics now allow individuals captured by trawls to be assigned to specific runs. Detailed information about movement and survival in the Delta has spurred development of agent-based models of juvenile salmon that are coupled to hydrodynamic models. Although much has been learned, knowledge gaps remain about how very small juvenile salmon (fry and parr) use the Delta. Understanding how all life stages of juvenile salmon grow, rear, and survive in the Delta is critical for devising management strategies that support a diversity of life history strategies. [ABSTRACT FROM AUTHOR]

Habitat use studies can be used to investigate ecological and behavioural patterns of animals and serve as useful tools for conservation planners. However, specific habitats essential to survival can be difficult to determine for highly mobile marine animals, especially when these species are rare or endangered., Active acoustic tracking telemetry was used to determine daily activity spaces and rates of movement of juvenile smalltooth sawfish ( Pristis pectinata) in critical habitat areas of south-west Florida, USA., Activity space size and rates of movement were positively related with the size of the area where the animal was tracked. Overall, activity spaces were small and ranged from 0.07-0.17 km2 using 95% minimum convex polygons, 0.01-0.16 km2 based on 50% kernel density estimates (KDE), and 0.08-0.68 km2 based on 95% KDE. Rates of movement ranged from 2.4 to 6.1 m min-1., There were no detectable differences in activity space or rates of movement between ebb and flood tide or high or low tide. Activity space decreased and rates of movement increased at night, possibly related to nocturnal foraging behaviour or predator avoidance. Comparisons of tracked animal locations and random locations suggested there was selection for those habitats in close proximity to mangrove shoreline., Though daily activity spaces were small, juvenile smalltooth sawfish did exhibit a daily expansion in activity space over the monitoring period., Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Many shark species form groups; yet the drivers of this behaviour are not well understood. Aggregations have been presumed to be a function of resource availability or phenology. However, recent studies have suggested that some sharks display preferences in their associations with conspecifics and that complex social networks may underpin their movement patterns, demographic distribution and fitness. This study used a network approach to investigate patterns of sociality of a benthic predator, the spotted wobbegong shark, Orectolobus maculatus (Family Orectolobidae), in a small marine reserve. Spatial data obtained from fine-scale passive acoustic telemetry were used to infer association preferences of 15 tagged sharks over a 15-month period. Thirty-five associating dyads emerged, with permutation tests indicating that these were nonrandomly formed. Many dyads were temporally stable, with some persisting even after sharks returned to the reserve from their seasonal migration. A complete but sparse network was observed and although association patterns were evident at the dyadic level, indication of stable communities or network structure was limited. The population was not found to be gregarious and exclusive pairs were not observed, with 14 sharks associating with more than one individual. Assortative mixing (by sex, size and familiarity) was not present and range overlap did not strongly correlate with association indices. This suggests that these relationships are not a random result of nonsocial grouping behaviours but can be explained, at least in part, by genuine social affiliation. As such, anthropogenic influences on the population may have more complex impacts than previously thought. [ABSTRACT FROM AUTHOR]

The miniaturization of acoustic transmitters enables researchers to tag smaller fish for telemetry studies, thus representing a greater proportion of the population of interest. Fish having a smaller transmitter burden (e.g., the weight of the transmitter relative to the weight of the fish) may also have fewer potential adverse transmitter effects. The development of an injectable acoustic transmitter has led to research that determined the least invasive and quickest method of implantation. Following that research, the objectives of this study were to determine the effects of transmitter implantation on swimming performance and predator avoidance, and to find a minimum size threshold of fish that can be tagged without adversely affecting those responses. To assess critical swimming speed ( U crit ; an index of prolonged swimming performance) and predator avoidance for juvenile Chinook Salmon ( Oncorhynchus tshawytscha ), fish were split into three treatments: (1) implantation with a dummy injectable acoustic transmitter (IAT treatment), (2) implantation with a dummy injectable acoustic transmitter and passive integrated transponder tag (IAT + PIT treatment), and (3) an untagged control. IAT treatment fish had lower U crit values than untagged controls among individuals below 79 mm fork length (transmitter burden 3.4–4.0%). U crit values for the IAT + PIT treatment were not significantly different from untagged controls and no size threshold was found. There was no significant difference in predator avoidance between fish implanted with the IAT or IAT + PIT compared to untagged controls. These guidelines could provide researchers and managers with a powerful tool to examine behavior and survival of small salmonids. [ABSTRACT FROM AUTHOR]

Overfishing is arguably the greatest ecological threat facing the oceans, yet catches of many highly migratory fishes including oceanic sharks remain largely unregulated with poor monitoring and data reporting. Oceanic shark conservation is hampered by basic knowledge gaps about where sharks aggregate across population ranges and precisely where they overlap with fishers. Using satellite tracking data from six shark species across the North Atlantic, we show that pelagic sharks occupy predictable habitat hotspots of high space use. Movement modeling showed sharks preferred habitats characterized by strong sea surface-temperature gradients (fronts) over other available habitats. However, simultaneous Global Positioning System (GPS) tracking of the entire Spanish and Portuguese longline-vessel fishing fleets show an 80% overlap of fished areas with hotspots, potentially increasing shark susceptibility to fishing exploitation. Regions of high overlap between oceanic tagged sharks and longliners included the North Atlantic Current/Labrador Current convergence zone and the Mid-Atlantic Ridge southwest of the Azores. In these main regions, and subareas within them, shark/vessel co-occurrence was spatially and temporally persistent between years, highlighting how broadly the fishing exploitation efficiently "tracks" oceanic sharks within their space-use hotspots year-round. Given this intense focus of longliners on shark hotspots, our study argues the need for international catch limits for pelagic sharks and identifies a future role of combining fine-scale fish and vessel telemetry to inform the ocean-scale management of fisheries. [ABSTRACT FROM AUTHOR]

The use of cell lines to test the toxicity of aquatic pollutants is a valuable alternative to fish bioassays. In this study, fibroblast SAF-1 cells from the marine gilthead seabream ( Sparus aurata L.) were exposed for 24 h to the heavy metals Cd, Hg, MeHg (Methylmercury), As or Pb and the resulting cytotoxicity was assessed. Neutral red (NR), MTT-tetrazolio (MTT), crystal violet (CV) and lactate dehydrogenase (LDH) viability tests showed that SAF-1 cells exposed to the above heavy metals produced a dose-dependent reduction in the number of viable cells. Methylmercury showed the highest toxicity (EC 50 = 0.01 mM) followed by As, Cd, Hg and Pb. NR was the most sensitive method followed by MTT, CV and LDH. SAF-1 cells incubated with each of the heavy metals also exhibited an increase in the production of reactive oxygen species and apoptosis cell death. Moreover, the corresponding gene expression profiles pointed to the induction of the metallothionein protective system, cellular and oxidative stress and apoptosis after heavy metal exposure for 24 h. This report describes and compares tools for evaluating the potential effects of marine contamination using the SAF-1 cell line. [ABSTRACT FROM AUTHOR]

External tagging of fish with electronic tags has been used for decades for a wide range of marine and freshwater species. In the early years of fish telemetry research, it was the most commonly used attachment method, but later internal implants became preferred. Recently, the number of telemetry studies using external tagging has increased, especially with the development of archival tags (data storage tags, DSTs), pop-up satellite archival tags (PSATs) and other environment-sensing tags. Scientific evaluations of the tagging method are rather scarce for most species. We identified 89 publications, reporting effects of external tagging for 80 different fish species, which constitute the main basis for this review. External attachment holds certain benefits compared to other tagging methods, for example, speed of application, and it may be the only option for fishes with a body shape unsuitable for surgical implantation, or when using tags with sensors recording the external environment. The most commonly reported problems with external tags are tissue damage, premature tag loss, and decreased swimming capacity, but the effects are highly context dependent and species specific. Reduced growth and survival have also been recorded, but direct mortality caused by external tagging seems rare. Most of the studies reviewed evaluate tag retention, survival, and tissue reactions. There is a general need for more research on the effects of external tagging of fish with electronic tags, but particularly there are few studies on predation risk, social interactions, and studies distinguishing capture and handling effects from tagging effects. For PSATs, especially those that are large relative to fish size, there are particular problems with a high proportion of premature tag losses, reduced swimming capacity, and likely increased predation, but there remains a paucity of tag effect studies related to the use of PSATs. Before embarking on a field study employing external tagging with electronic tags, we recommend the use of appropriate pilot studies, controlled where possible, to quantify potential impacts of tagging. [ABSTRACT FROM AUTHOR]

Background: Biotelemetry has many advantages for monitoring fish behaviour. However, the accuracy of results can be impacted by changes in fish behaviour following tagging and other forms of human intervention. Different fish take different amounts of time to return to normal behaviour patterns. This recovery period is often difficult to assess. In many studies, it is simply ignored, while in others an assumed duration is used. This assumption is rarely based on objective criteria. To address this challenging aspect of fish telemetry, a multi-criteria stepwise approach was developed based on complementary criteria obtainable through prior knowledge of the normal behaviour of studied species (home range, diel rhythm, homing, shoaling, migration…). It was applied to the case study of an acoustic telemetry project in the Seine Estuary (France) for three estuarine species exhibiting contrasted ecological traits: European eel Anguilla anguilla (Linnaeus 1758), thin lipped grey mullet Liza ramada (Risso 1827) and bream Abramis brama (Linnaeus 1758). Results: Taking into account the particular traits of the species studied, we used the following three criteria: time to return to core area of activity, time to return to rhythmic activity, and time to return to site of capture. Post-release periods of recovery varied greatly between species. The median value was 10 days for eel, 25 days for mullet, and 1 day for bream. During this period, eels moved very little and the schedule pattern presented a diel rhythm with most detections occurring at night. All mullet exhibited rapid downstream trajectories after release, with larger distances covered during the ebb. Only five individuals returned later to the study site. This behaviour turns out to be not only an effect of post-release stress, but also the result of normal shifts in feeding habitat use by large shoals of mullet. Common bream exhibit very short periods of recovery with strong site fidelity. Most of the individuals of the different species (72%) return to their site of capture. Conclusions: The approach allows the identification of individual periods of recovery specific to the species and environment being studied. It maximises the amount of conserved data representing normal behaviour and can be implemented with various types of tracking data. Analysis of this period provides additional information about the stress response of species and their associated behaviour. [ABSTRACT FROM AUTHOR]

The advancement of telemetry control for the water industry has increased the difficulty of managing large volumes of nuisance alarms (i.e., alarms that do not require a response). The aim of this study was to identify and reduce the number of nuisance alarms that occur for Northern Ireland (NI) Water by carrying out alarm duration analysis to determine the appropriate length of persistence (an advanced alarm management tool) that could be applied. All data were extracted from TelemWeb (NI Water's telemetry monitoring system) and analyzed in Excel. Over a 6-week period, an average of 40 000 alarms occurred per week. The alarm duration analysis, which has never been implemented before by NI Water, found that an average of 57% of NI Water alarms had a duration of <5 minutes. Applying 5-minute persistence, therefore, could prevent an average 26 816 nuisance alarms per week. Most of these alarms were from wastewater assets. [ABSTRACT FROM AUTHOR]

The article focuses on technological innovations that are enhancing telemetry of aquatic animals. It states that telemetry innovations have improved observations of aquatic animal behavior and movement and provide ecological insight by connecting the movements of aquatic animals with measures of their environment and physiology. It comments on the development of global collaborative efforts to facilitate data sharing and management, and infrastructure in aquatic telemetry.

The marine environment is increasingly pressured from human activities, such as offshore renewable energy developments. Offshore wind farms may pose direct risks to seabirds at protected breeding sites. However, changes in food availability may influence foraging behaviour and habitat use during the breeding season or between years. Consequently, seabird–wind farm interactions, and risks posed to populations, may vary over longer time scales, but this has seldom been quantified. We used GPS-telemetry to study the movements of 25 lesser black-backed gulls from the Alde–Ore Special Protection Area (SPA), UK between 2010 and 2012, while birds were associated with their breeding colony. Variation in movements away from the colony, offshore, and in operational, consented and proposed Offshore Wind Farm Areas (“OWFAs”) was investigated: (1) between years and (2) across the breeding season, addressing: (3) sex-specific, (4) individual and (5) diurnal/nocturnal differences. The extent of overlaps with OWFAs varied between years, being greatest in 2010 (7/10 birds showing connectivity; area overlap: 6.2 ± 7.1%; time budget overlap: 4.6 ± 6.2%) and least in 2012. Marine habitats close to the colony were used before breeding. Birds spent little time offshore as incubation commenced, but offshore usage again peaked during the early chick-rearing period, corresponding with use of OWFAs. Individuals differed in their seasonal interactions with OWFAs between years, and males used OWFAs significantly more than females later in the breeding season. This study demonstrates the importance of tracking animals over longer periods, without which impact assessments may incorrectly estimate the magnitude of risks posed to protected populations. [ABSTRACT FROM AUTHOR]

Artificial weirs on the Mulkear River present an obstacle to sea lamprey (Petromyzon marinus L.) during upstream spawning migration. Telemetry to monitor passage success was undertaken in 2010 and repeated in 2011 following modifications to two of the weirs in the lower section of the river. Upstream migrants, captured downstream of the first weir, were radio tagged during 2010 (n = 51) and 2011 (n = 36). During both years tagged fish were experimentally re-released in two batches downstream (n = 20 both years) and upstream (n = 31 for 2010; n = 16 for 2011) of this structure, respectively. Subsequent telemetry conducted over nine weeks in 2010 suggested the majority of sea lamprey movements were downstream, with only one tagged fish ascending any of the weirs. Some fish spawned downstream of the first weir while other fish descended further to known spawning sites on the River Shannon both up and downstream of the Mulkear confluence. During 2011, localised movements were recorded up to but not across the first weir for the downstream-released fish. Of the 16 fish released upstream, three (19%) ascended the modified third weir and progressed further into the catchment compared with 0% (0/31) the previous year. [ABSTRACT FROM AUTHOR]

Expansion of the American white pelicanPelicanus erythrorhynchoscolony on Blackfoot Reservoir, Idaho, and the associated declines in adfluvial Yellowstone Cutthroat TroutOncorhynchus clarkii bouvieriin the upper Blackfoot River drainage has generated concern about the impact of pelican predation on this native trout stock. During a 4-year study, 4,653 wild Yellowstone Cutthroat Trout were tagged using a combination of radiotelemetry and PIT tags. Annual predation rate estimates were made by recovering Yellowstone Cutthroat Trout tags from the nesting islands of American white pelicans. On-island tag recovery rates were corrected for ingested tags that went undetected during island searches and for tags that were deposited away from the nesting islands. American white pelicans consumed tagged Yellowstone Cutthroat Trout ranging from 150 mm to 580 mm TL and showed no size selection within that range for their prey. Predation rates on adult and juvenile Yellowstone Cutthroat Trout generally exceeded 20%, and the highest values were above 60%. Our independent methods (telemetry and PIT tagging) for estimating pelican predation on adult Yellowstone Cutthroat Trout produced similar results. Annual river flow conditions varied markedly and may have contributed to some of the observed range in predation rate estimates. Predation by the pelican colony appears to be a likely contributor to the recent collapse of Yellowstone Cutthroat Trout in the upper Blackfoot River drainage. In the past, overexploitation by anglers severely reduced the trout population and was remedied by implementing catch-and-release regulations. The current predation impact poses a greater management challenge, namely, finding a balanced approach for conserving both the native trout stock and the pelican colony. Received April 29, 2014; accepted February 5, 2015 [ABSTRACT FROM PUBLISHER]

Movement of WalleyesSander vitreusamong reaches in a large, fragmented river was assessed by employing a combination of tagging, telemetry, and genetic analyses. Our objective was to determine whether the existing dams in the Ottawa River, Canada, were impeding Walleye movement among river reaches. Movement was predicted to be greater among contiguous, unimpounded reaches in comparison with impounded reaches. In total, 1,586 Walleyes were tagged in five river reaches, and 35 Walleyes were tracked by radiotelemetry in three river reaches. Genetic analyses (linkage disequilibrium, genetic divergence and diversity, effective population size, genetic structuring, bottlenecks, and migration rates) were conducted on 221 Walleyes from seven river reaches by genotyping at six microsatellite loci. Based on both tag returns (return rate = 12.1%) and telemetry data, there was limited movement among river reaches whether impounded or unimpounded, and movement was predominately upstream. Genetic analyses identified population structuring, with three genetic groupings occurring within the river. There was also evidence of genetic isolation in an upper reach of the river, indicating potential residual effects of a bottleneck or genetic drift. Our results suggest that existing dams may not act as significant barriers to Walleye movement in the Ottawa River, but limited movements appear to maintain genetic diversity and minimize genetic drift. Consequently, maintaining the genetic attributes of Walleye stocks in segmented rivers may require some level of fish passage. Received July 9, 2012; accepted January 16, 2015 [ABSTRACT FROM PUBLISHER]

Tournament displacement, stockpiling near release points, and handling stress are major concerns for managers of sport fisheries in the southeastern USA. We examined the effects of transport distance and tournament handling stress on dispersal of 40 Largemouth BassMicropterus salmoidesvia telemetry from May 2012 to September 2013 in the Albemarle Sound system of eastern North Carolina. Largemouth Bass were captured from four tributaries of Albemarle Sound and transported 16.5–45 km to a central release point before being acoustically tagged and released. Movement data from an array of passive receivers was used to calculate rates of dispersal from the release point, emigration from the study area and return to capture location over time. Blood cortisol concentration, collected from our tagged Largemouth Bass and those captured in an actual tournament, was used to determine the effect of stress on potential postrelease movement and survival. Our findings indicate little evidence of long-term stockpiling (i.e., fish remaining close to release point; Richardson-Heft et al. 2000); 57% of displaced Largemouth Bass dispersed more than 500 m from the release point within 7 d and 87% within 21 d postrelease. Half of those that emigrated from Edenton Bay returned to their capture location. However, no Largemouth Bass displaced 35–45 km returned to their capture locations, suggesting that long-distance displacement inhibits return. Fishing (2.8%) and nonharvest mortality (0.5%) were low throughout this study except for peaks observed during late spring (42.9%) and early summer (25.1%) of 2013. Mean cortisol concentrations were similar in Largemouth Bass collected during our simulated tournament (126.7 ng/mL) and an actual tournament (118.4 ng/mL). However, cortisol concentrations were unrelated to survival, postrelease dispersal, or return of tagged individuals to their capture location. Largemouth Bass appear to be able to cope with current tournament practices; however, restrictions on displacement distance may increase return rates. Received August 26, 2014; accepted January 14, 2015 [ABSTRACT FROM PUBLISHER]

Telemetry is increasingly being used to estimate population-level survival rates. However, these estimates may be affected by the detectability of telemetry tags and are reliant on the assumption that telemetry data represent the movements of the tagged fish. Predation on tagged fish has the potential to bias survival estimates, and unlike the issue of detectability, methods to correct for the resulting bias (termed 'predation bias') are not yet developed. In an acoustic telemetry study on inner Bay of Fundy Atlantic salmon ( Salmo salar) smolts during 2008 and 2011, unusual tag detection patterns were indicative that some data may have been representative of the movements of predators rather than smolts. To incorporate predation effects into the resulting survival estimates, a suite of 11 summary migration metrics were compared between Atlantic salmon smolts and striped bass ( Morone saxatilis). Cluster analyses revealed that 2.4% to 13.6% of tags implanted in smolts exhibited migration patterns more similar to striped bass than to other smolts, which was interpreted here as evidence of predation. Reassigning the fate of these tags as 'depredated-died' reduced estimated survival from 43.5% to 41.1% in 2008 and from 32.6% to 19.0% in 2011 relative to a traditional mark-recapture model, illustrating the effect of predation bias in this case study. [ABSTRACT FROM AUTHOR]

Actual sea waves and vessel motion are an unsteady nonlinear random process. The currently adopted test to simulate wave impact of vessel models in tank can't fully reveal the impact of real sea waves on vessel swing motion. In this paper the buoy wave height meter is adopted to carry out measurements and analyses of the coastal wave environment. The correlation between the coastal wave spectra and the ocean wave spectra is analyzed. The test system is established for remote control and telemetry self-propelled vessel models suitable for the experiment conducted in the coastal areas. The seakeeping performance test is conducted for the same tonnage of round bilge vessel model and the deep-V hybrid monohull of large-scale vessel model under the coastal wave conditions. The experimental results are compared with the test results of small-scale vessel model in the towing tank. The experimental results show that the seakeeping performance of the deep-V hybrid monohull is improved by a wide margin in contrast to that of the round bilge model, and there is a marked difference between the motion characteristics of large-scale vessel models in the coastal wave environment and that of small-scale vessel models in tank. [ABSTRACT FROM AUTHOR]

With advances in technology and demand for life history information, researchers are increasingly conducting invasive procedures on fish that require an anesthetic. This study examined the effectiveness of electronarcosis as a field anesthetic on Atlantic SturgeonAcipenser oxyrinchus oxyrinchusduring the spawning season in the James River, Virginia. Concerns about sampling Atlantic Sturgeon during spawning runs prompted our examining whether movements after capture, narcosis, and tagging were noticeably modified. An electronarcosis system, which consisted of a power supply, fiberglass tank, and hardware cloth, were set up both on land and on a sampling boat. During the spawning season Atlantic Sturgeon were caught and implanted with Vemco V16 telemetry tags using electronarcosis as an anesthetic. Anesthesia induction, surgery, and recovery averaged 5 min. Telemetry data from the tagging year was compared with returning fish tagged in previous years. This showed movements during the spawning season and spawning exit dates were similar between the two groups, suggesting that electronarcosis was effective and time-efficient for conducting invasive procedures. Capturing and implanting transmitters in Atlantic Sturgeon during spawning runs does not appear to modify spawning movements. Managers may benefit from targeting adult Atlantic Sturgeon and other iteroparous anadromous fishes in rivers during spawning periods, which is typically very efficient due to high densities of fish during that period. Received February 21, 2014; accepted December 31, 2014 [ABSTRACT FROM AUTHOR]