Movement and Behavior of Walleye, Stizostedion Vitruem Vitreum (Mitchell), in Jamestown Reservoir, North Dakota, As Determined by Biotelemetry

Radio biotelemetry was used to study the movements and behavior of walleyes in Jamestown Reservoir during the summer of 1980. Four walleyes weighing from 1.7 to 4.4 kg were surgically implanted with radio transmitters. Only one fish could be successfully tracked. It was found that conductivity prevented the reception of radio signals from water deeper than 4.5 m. In 1981, eight walleyes were surgically implanted with ultrasonic transmitters. The ultrasonic transmitters performed as expected. Seven walleyes were successfully tracked throughout the summer. Two of the walleyes appeared to be nomadic and did not form activity areas. Five walleyes formed activity areas, with two fish having multiple activity areas. The average size of the activity area was 45.4 ha. Three types movement patterns were observed; directional, random, and movements following the shoreline. Walleyes were seldom found resting. The walleyes moved into deeper water as the summer progressed. Four to five meters was the average locational depth. Light did not limit the fish\u27s activity in shallow water. No relationship was evident between weather conditions and other outside influences on walleye activity

Review of NRA tracking projects on salmon, Salmo salar L., and sea trout, Salmo trutta L

The report briefly outlines the programme of the National Rivers Authority (NRA), placing the Fisheries programme in the context of the work of the NRA as a whole, and viewing the tracking work against the broader requirements of the NRA Fisheries research programme. All regions of England and Wales are considered. Two techniques currently exist for studying the detailed timing and extent of movements of adult salmon: tracking of individually identifiable fish, and counting the numbers of fish moving past a fixed point in the river. The development of tracking techniques and the integrated use of tracking and fish counters is briefly reviewed in Section 3. Further details of these techniques are given in Appendices. Section 4 summarises and assesses completed and current NRA tracking studies. Section 5 discusses the scientific content of these studies in relation to similar work carried out elsewhere in the UK. The NRA programme of tracking studies is evaluated in Section 6. Section 7 discusses future fisheries projects and Section 8 details the future development of tracking techniques. Finally, recommendations arising out of this review are summarised in Section 9

Seasonal movement and macro-habitat use of largemouth bass (Micropterus salmoides) in an Ohio River navigation pool

Largemouth bass provide an important recreational fishery in the Ohio River. Our objectives were to determine critical over-wintering and spawning habitats of largemouth bass in the Belleville Pool of the Ohio River. We surgically implanted radio-transmitters in 39 adult largemouth bass and tracked them over a 23-month period. Our results demonstrate the importance of off-channel habitats in the life history of largemouth bass in large river systems. Sedimentation, resulting in a loss of embayment quality and surface area, is an important problem and thus merits increased attention. Restoration and protection efforts to improve largemouth bass fisheries in large river systems should be concentrated in embayment habitats. In a related experiment, a model that related depth of transmitter to the maximum distance of detection imply that radio telemetry studies may underestimate use of deep-water habitats by fishes

Population Characteristics, Habitats, and Movements of Lake Sturgeon (Acipenser fulvescens) in the Lower Niagara River

Before my study, anecdotal information, such as incidental catches and reported sightings, provided the only means of assessing lake sturgeon, a species listed as threatened in New York State, in the lower Niagara River. The objectives of my study were to ( 1) assess the population of lake sturgeon by collecting and analyzing age, growth, and CPUE data, (2) compare the habitats and movements of adults and juveniles, and (3) identify potential spawning, feeding, and nursery habitats and compare use of these habitats between adults and juveniles. From late July 1998 through August 2000, 67 lake sturgeon were captured using gill nets, baited setlines, and SCUBA divers. Overall, divers (2.5 fish/night) performed better than gill nets (0.25 fish/night) and setlines (0.23 fish/night). Age of lake sturgeon captured ranged from 1 to 23 years, with most fish (n = 47) less than 10 years old. Six percent (4 out of 63) of the lake sturgeon captured had deformities, such as spinal curvature. Ultrasonic transmitters were attached to 24 fish (12 adults and 12 juveniles) to determine their habitat use and movements. Depth, current velocity, and substrate uses were similar between juvenile and adult fish. Monitoring the movements of adult fish during likely spawning temperatures (11 to 18°C) revealed that fish congregated both 8 to 10 km up river and within 5 km of the river\u27s confluence with Lake Ontario. Based on the results of my study, I recommend that the lake sturgeon in the lower Niagara River remain listed as threatened by the NYSDEC and that the commercial and recreational fisheries remain closed. In addition, I recommend further studies investigating year class abundance, the cause of growth deformities, and the abundance and availability of food resources

Movement ecology of the Greenland shark (Somniosus microcephalus): Identifying tools, management considerations, and horizontal movement behaviours using multi-year acoustic telemetry

Arctic ecosystems are highly seasonally dynamic, and as such, mobile Arctic species have adopted movement patterns that correspond to the occurrence of productivity hotspots. As polar regions continue to warm at an unprecedented rate, the predictable occurrence of these hotspots of may be reduced, resulting in dire consequences for long-lived or slow-adapting species. Effective marine management approaches will therefore rely on an understanding of the ability of Arctic predators to confer community stability by linking disparate food webs and by responding flexibly to environmental change. This thesis describes the use of static acoustic telemetry to examine the long-term movement patterns of a model mobile predator, the Greenland shark (Somniosus microcephalus) within two distinct habitat types (coastal and offshore waters) and across multiple years (7 y). Movement records for 155 tagged Greenland sharks revealed strong seasonality in coastal and offshore residency driven by fluctuations in sea-ice cover, with evidence of site fidelity to specific sites (receivers) in both regions. Juvenile sharks remained in coastal regions for longer durations than subadults, however, no size-based spatial segregation was observed. At a localized scale, sharks used deep-water channels to direct movements between a coastal fjord system and offshore waters, where they exhibited transient behaviour near offshore moorings located outside of identified hotspot regions. Ultimately, this research provides novel insight into the long-term movement dynamics of this potentially vulnerable Arctic predator and will inform future management practices that promote the longevity of this species

The ecology of blacktail redhorse Moxostoma poecilurum in West Fork Thompson Creek, Louisiana

This study was designed to examine home range sizes and habitat use of blacktail redhorse Moxostoma poecilurum in West Fork Thompson Creek, Louisiana. Blacktail redhorse are a common non-game species found in Louisiana and other southeastern states. Adult blacktail redhorse (N=40; 187-273 mm total length) were implanted with radio transmitters and tracked twice weekly from February to September 2006 and from February to July 2007. To assess blacktail redhorse diet I analyzed 32 stomachs from fish collected by backpack electrofishing. I also conducted mark-recapture surveys of fish sampled monthly from May 2006 until July 2007. To assess homing ability in blacktail redhorse, I radio-tagged 10 individuals in 2007 and relocated them downstream (0.8 or 1.6 km) from their capture location. Results showed that implanted fish exhibited extremely high mortality or expulsion rates with 70% of all implanted transmitters being lost, even though retention rates in the laboratory were very high. On numerous occasions, I directly and indirectly observed avian and mammalian predators foraging in the study area, which likely explains high transmitter loss. Individual 95% linear home range sizes varied from 25 to 3,900 meters, with several fish having multiple home ranges, while others remained in the same pool throughout the study. Blacktail redhorse were observed foraging throughout the diel period, and their diet was primarily composed of chironomid (55%) and heptageniid larvae (17%). Similar to other redhorse species, blacktail redhorse were benthic feeders and foraging behaviors appear very similar to that of black redhorse Moxostoma duquesnei. Few marked individuals were recaptured (6 of 130) as indicated by mark-recapture sampling. The homing study showed only one individual moved back to its capture location. Small sample sizes and short study times limited both the mark-recapture and homing studies. Overall, blacktail redhorse exhibited a preference for pools with clay boulders, complex habitat, and undercut banks. The high levels of predation observed throughout this study and its impact on blacktail redhorse abundance suggest that local predation pressures structure this portion of the population and may be a driving force in structuring the entire headwater stream fish community in this area

Spatial ecology of adult spotted seatrout, Cynoscion nebulosus, in Louisiana coastal waters

Spotted seatrout, Cynoscion nebulosus, are common in estuaries and coastal waters of the south Atlantic and Gulf of Mexico and are of considerable recreational and economic importance. Still, the spatial ecology of this species is under-studied and poorly resolved, especially in Louisiana waters. To address this important knowledge gap, I examined the movements, distribution, and habitat use of adult spotted seatrout in coastal Louisiana primarily using high-resolution acoustic telemetry and secondarily, conventional tagging (mark-recapture) data. At the largest spatial scale investigated, I found that adults exhibited a high degree of estuarine fidelity and rarely undertook large-scale movements in excess of 50 km. At smaller (intra-estuarine) spatial scales, abiotic factors had a strong effect on fish distribution. Specifically, fish primarily utilized deeper channel habitats during severe weather events (cold storms and tropical fronts) and females avoided olighaline waters (0.5-5 psu). Adult spotted seatrout also showed clear habitat preferences, whereby oyster reefs and mud-bottom habitats of the estuary proper were used to a greater extent than channel and marsh regions. Seasonal and size trends in habitat use were also evident, as larger fish (\u3e 400 mm TL) showed a high affinity for structured (reef) habitats and across size classes, artificial reefs were utilized most during spring and summer. My results have direct bearing on the assessment and management of this important species and support the current initiative of an ecosystems-approach to management by informing spatial management options. Finally, the results of my methods validation work on the effects of tagging on spotted seatrout and performance dynamics of telemetry equipment have important implications for future studies. Given the high transmitter retention and survival of telemetered spotted seatrout in my holding experiments, biotelemetry should be a feasible approach for future studies on the movement and behavior of this species. Still, in designing receiver arrays to study fish movements (of any species), it will be necessary to consider the high variability in receiver detection ranges as revealed by my extensive range testing efforts

Acoustic telemetry in freshwater habitats: the influence of macrophytes on acoustic transmitter detection efficiency and identifying predation using novel transmitters

Acoustic telemetry is a popular tool to study the movements of animals and has resulted in substantial ecological knowledge gain. To effectively carry out acoustic telemetry studies, many technical and biological considerations must be made. This thesis aimed to fill gaps in knowledge pertaining to two common considerations in passive acoustic telemetry studies, particularly in nearshore freshwater habitats: understanding the influence of macrophytes on the detection efficiency and range of acoustic telemetry equipment and identifying whether or not tagged animals have been consumed by an aquatic predator. Through the application of detection range testing and hydroacoustic surveys, it was revealed that distance and macrophyte biovolume interact to significantly influence the detection efficiency of acoustic transmitters, and this influence varied significantly based on the seasonal growth and senescence of macrophytes. The distance at which 50% of transmissions were successfully detected ranged from 5.5 m (± 139.6 S.D.) to 186.8 m (± 114.4 S.D.) and was significantly correlated to seasonal fluctuations in macrophyte biovolume. One of the first field applications of novel transmitters that identify predation events of tagged individuals indicated that 31.7% of tagged fish (n = 60) were apparently predated, and variable detection patterns were demonstrated using spatial metrices to examine the transmitter movements before and after the apparent predation event. The novel information presented in this thesis regarding the significant seasonal influence of macrophytes on detection efficiency and range and the application of acoustic transmitters that identify predation events in the wild will inform and improve future acoustic telemetry studies

Contributory studies to the development, validation and field use of a telemetry system to monitor ventilation and trophic activity in wild Brown Trout

This work was performed as part of a major research project into the evaluation of the ecology of lake dwelling Brown Trout, Salmo trutta L. using ultrasonic biotelemetry techniques. The supplementary research results. leading up to and after the execution of a program of experiments involving the telemetry of feeding and ventilatory rhythms are described: 1. The presence of red (slow) fibres in the adductor mandibulae muscle of Brown Trout was confirmed to be as previously described in the Rainbow Trout, Sälmo gairdneri Richardson and other salmonids. 2. By electromyographic (EMG) and pharmacological means, the red fibres in the a. mandibulae were shown to be active during ventilation and the mosaic fibres comprising the bulk of the muscle were recruited during more dynamic events such as feeding and coughing. Observations were made on the innervation of the red fibres. 3. Comparative investigations made at sea on large deep sea Squaloid and Galeoid sharks (which have a simple adductor muscle like the Trout) showed an identical functional differentiation as obtained in the Trout. 4. The presence of a migratory 'pace setter potential' was found for the first time in Fish. Its use as an indicator of feeding activity by telemetry was rejected on practical grounds. ýýY NO 5. An ultrasonic transmitter was developed to telemeter an analogue of the adductor mandibulae EMG from wild Brown Trout, using a novel electrode design. Four fish were so equipped and released into Airthrey Loch, University of Stirling and tracked for up to 24 hours (following a 24 hr allowance for post-anaesthetic recovery). Feeding and ventilatory periodicity, linear and angular movement patterns and photoperiod were intercorrelated. Angle of turn and subsequent step length were positively correlated and feeding activity was marked by a preference for dextral turning. 'Area restricted searching' and 'area avoided searching' were the probable causes of the movement patterns seen in this and previous investigations at Airthrey Loch. A depth preference and orientation of the fish to topography was demonstrated. Following analysis of the angle of turn and step length data, it was concluded that the larger transmitter package and more severe surgery materially affected the fishes' behaviour relative to data previously obtained at Airthrey Loch using smaller transmitters. 6. Due to difficulties experienced in 5 above due to an unsuspected effect on the a. mandibulae EMG detectable up to 24 hrs post-anaesthesia, a frequency analysis was made of the a. mandibulae EMG of the Brown Trout and several other species. This disclosed that the EMG from red fibres has a frequency spectrum considerably lower than that of 'standard' mammalian muscle. The progressive failure of the EMG transmitter with time was due to a combination of the anaesthetic effect and the frequency spectrum relative to certain design features. (vii, In the light of these observations, subsequent designs of the EMG transmitter were able to take this into account