共查询到20条相似文献,搜索用时 15 毫秒
1.
K. C. Hanson S. J. Cooke C. D. Suski G. Niezgoda F. J. S. Phelan R. Tinline D. P. Philipp 《Hydrobiologia》2007,582(1):243-256
A whole-lake acoustic telemetry array was utilized to monitor the three-dimensional position of 20 largemouth bass (Micropterus salmoides). Code division multiple access (CDMA) technology enabled the simultaneous monitoring of the 20 transmitters (equipped with
pressure and temperature sensors) at 15 s intervals with sub-meter accuracy. Fish were monitored between November 2003 and
April 2004 to evaluate the behaviour of fish across different temporal and spatial scales. The distance moved by largemouth
bass, assessed both on a daily and hourly basis, varied by season and was positively correlated with water temperature. For
example, daily movement rates were 2.69 ± 1.45 km/day in mid November (average daily water temperature 5.9°C), 2.24 ± 0.73 km/day
in early January (5.1°C), and 7.28 ± 2.62 km/day in mid April (7.7°C). Interestingly, daily movement rates varied by as much
as 25 fold among individual fish. Visualization of fish swimming paths revealed that whereas some fish occupied discrete areas
and made only localized movements, other individuals made lengthier journeys covering much of the lake in periods of as little
as one day. Analysis of fish behaviour at a finer temporal scale revealed that during the winter, fish spend more than 95%
of their time swimming at speeds less than 0.1 m/s (0.07 ± 0.24 m/s). During late fall, and especially in spring, swimming
speeds were higher with mean swimming speeds of 0.11 ± 0.27 m/s and 0.19 ± 0.29 m/s, respectively. When the telemetry dataset
was queried to simulate 24 h manual tracking intervals, it was clear that manual tracking data would not have been representative
of actual daily movement rates, underestimating daily movement and swimming speeds by at least 75 fold. This study identifies
the importance of evaluating fish activity at multiple spatial (whole lake to sub-meter position) and temporal (seasonal to
seconds) scales and illustrates the potential of CDMA telemetry to yield such data. 相似文献
2.
Manuela Capello Marianne Robert Marc Soria Gael Potin David Itano Kim Holland Jean-Louis Deneubourg Laurent Dagorn 《PloS one》2015,10(8)
The rapid expansion of the use of passive acoustic telemetry technologies has facilitated unprecedented opportunities for studying the behavior of marine organisms in their natural environment. This technological advance would greatly benefit from the parallel development of dedicated methodologies accounting for the variety of timescales involved in the remote detection of tagged animals related to instrumental, environmental and behavioral events. In this paper we propose a methodological framework for estimating the site fidelity (“residence times”) of acoustic tagged animals at different timescales, based on the survival analysis of continuous residence times recorded at multiple receivers. Our approach is validated through modeling and applied on two distinct datasets obtained from a small coastal pelagic species (bigeye scad, Selar crumenophthalmus) and a large, offshore pelagic species (yellowfin tuna, Thunnus albacares), which show very distinct spatial scales of behavior. The methodological framework proposed herein allows estimating the most appropriate temporal scale for processing passive acoustic telemetry data depending on the scientific question of interest. Our method provides residence times free of the bias inherent to environmental and instrumental noise that can be used to study the small scale behavior of acoustic tagged animals. At larger timescales, it can effectively identify residence times that encompass the diel behavioral excursions of fish out of the acoustic detection range. This study provides a systematic framework for the analysis of passive acoustic telemetry data that can be employed for the comparative study of different species and study sites. The same methodology can be used each time discrete records of animal detections of any nature are employed for estimating the site fidelity of an animal at different timescales. 相似文献
3.
Mensinger AF Deffenbaugh M 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2000,355(1401):1305-1308
An acoustic neural telemetry tag has been developed for recording from free-swimming aquatic animals. Microwire electrodes were implanted into the VIIIth nerve of the toadfish, Opsanus tau, and interfaced to the subdermally implanted tag. The telemetry tag frequency modulates the neural signal, converting it into a varying frequency, which is amplified and transmitted acoustically (centre frequency of 90 kHz and a 20 kHz bandwidth). This acoustic signal is detected by a receiver hydrophone, and the receiver reconstructs the full neural waveform from the acoustic signal. However, due to the multipath environment in the experimental aquarium, the acoustic signal is quickly degraded as the hydrophone is moved away from the source. In order to receive the signal independent of fish position, an anechoic aquarium was designed. Streams of microbubbles (ca. 70 microm diameter) were generated to produce a curtain of sound-absorptive material along the walls and water surface of the aquarium. Microbubble generation significantly reduced the multipath artefacts, and allowed signal discrimination independent of fish and hydrophone position. The anechoic aquarium will allow the recording of neural activity from free-swimming fishes in quasi-natural habitats, thus allowing better understanding of the neural mechanisms of behaviour. 相似文献
4.
Cunjak RA Roussel JM Gray MA Dietrich JP Cartwright DF Munkittrick KR Jardine TD 《Oecologia》2005,144(4):636-646
Information about animal movements has often been inferred from stable isotope analysis (SIA), but is dependent on animals
assimilating site-specific isotopic signatures via diet. This potential weakness in ecological interpretation can be overcome
by using other investigative tools that provide precise information about individual movement patterns. In this paper, we
demonstrate the value of combining SIA with telemetry or mark-recapture data from trapping, electrofishing and remote detection
of individuals to study the movement and feeding ecology of fishes in different habitats. In a fjord lake system in Newfoundland,
Canada, juvenile Atlantic salmon delayed downstream migration (smolts) or actively moved into a large lake (parr) where they
foraged for periods reflecting different life history strategies. In the Miramichi River (New Brunswick, Canada), SIA provided
evidence of distinct foraging habitats (tributary versus large river). By tracking fish implanted with passive integrated
transponder (PIT) tags, we distinguished between movements related to foraging versus seeking cool water refugia during high
temperature events. Finally, site fidelity and limited mobility of slimy sculpin, a small benthic fish, was established where
δ13C in muscle tissue showed a progressive enrichment downstream and where a median displacement of <10 m was estimated for sculpin
tagged with PIT tags. Technological improvements have permitted non-destructive tissue sampling of wild fishes for SIA, and
the tagging and remote detection of animals smaller than was previously possible. These advancements and the combination of
investigative tools promise new insights into animal ecology. 相似文献
5.
Line transect sampling is a distance sampling method for estimating the abundance of wild animal populations. One key assumption of this method is that all animals are detected at their initial location. Animal movement independent of the transect and observer can thus cause substantial bias. We present an analytic expression for this bias when detection within the transect is certain (strip transect sampling) and use simulation to quantify bias when detection falls off with distance from the line (line transect sampling). We also explore the non-linear relationship between bias, detection, and animal movement by varying detectability and movement type. We consider animals that move in randomly orientated straight lines, which provides an upper bound on bias, and animals that are constrained to a home range of random radius. We find that bias is reduced when animal movement is constrained, and bias is considerably smaller in line transect sampling than strip transect sampling provided that mean animal speed is less than observer speed. By contrast, when mean animal speed exceeds observer speed the bias in line transect sampling becomes comparable with, and may exceed, that of strip transect sampling. Bias from independent animal movement is reduced by the observer searching further perpendicular to the transect, searching a shorter distance ahead and by ignoring animals that may overtake the observer from behind. However, when animals move in response to the observer, the standard practice of searching further ahead should continue as the bias from responsive movement is often greater than that from independent movement. 相似文献
6.
The Argos-CLS Kalman Filter: Error Structures and State-Space Modelling Relative to Fastloc GPS Data
Understanding how an animal utilises its surroundings requires its movements through space to be described accurately. Satellite telemetry is the only means of acquiring movement data for many species however data are prone to varying amounts of spatial error; the recent application of state-space models (SSMs) to the location estimation problem have provided a means to incorporate spatial errors when characterising animal movements. The predominant platform for collecting satellite telemetry data on free-ranging animals, Service Argos, recently provided an alternative Doppler location estimation algorithm that is purported to be more accurate and generate a greater number of locations that its predecessor. We provide a comprehensive assessment of this new estimation process performance on data from free-ranging animals relative to concurrently collected Fastloc GPS data. Additionally, we test the efficacy of three readily-available SSM in predicting the movement of two focal animals. Raw Argos location estimates generated by the new algorithm were greatly improved compared to the old system. Approximately twice as many Argos locations were derived compared to GPS on the devices used. Root Mean Square Errors (RMSE) for each optimal SSM were less than 4.25km with some producing RMSE of less than 2.50km. Differences in the biological plausibility of the tracks between the two focal animals used to investigate the utility of SSM highlights the importance of considering animal behaviour in movement studies. The ability to reprocess Argos data collected since 2008 with the new algorithm should permit questions of animal movement to be revisited at a finer resolution. 相似文献
7.
8.
Elizabeth M. Phillips John K. Horne Jeannette E. Zamon Jonathan J. Felis Josh Adams 《Ecology and evolution》2019,9(8):4805-4819
Studies estimating species' distributions require information about animal locations in space and time. Location data can be collected using surveys within a predetermined frame of reference (i.e., Eulerian sampling) or from animal‐borne tracking devices (i.e., Lagrangian sampling). Integration of observations obtained from Eulerian and Lagrangian perspectives can provide insights into animal movement and habitat use. However, contemporaneous data from both perspectives are rarely available, making examination of biases associated with each sampling approach difficult. We compared distributions of a mobile seabird observed concurrently from ship, aerial, and satellite tag surveys during May, June, and July 2012 in the northern California Current. We calculated utilization distributions to quantify and compare variability in common murre (Uria aalge) space use and examine how sampling perspective and platform influence observed patterns. Spatial distributions of murres were similar in May, regardless of sampling perspective. Greatest densities occurred in coastal waters off southern Washington and northern Oregon, near large murre colonies and the mouth of the Columbia River. Density distributions of murres estimated from ship and aerial surveys in June and July were similar to those observed in May, whereas distributions of satellite‐tagged murres in June and July indicated northward movement into British Columbia, Canada, resulting in different patterns observed from Eulerian and Lagrangian perspectives. These results suggest that the population of murres observed in the northern California Current during spring and summer includes relatively stationary individuals attending breeding colonies and nonstationary, vagile adults and subadults. Given the expected growth of telemetry studies and advances in survey technology (e.g., unmanned aerial systems), these results highlight the importance of considering methodological approaches, spatial extent, and synopticity of distribution data sets prior to integrating data from different sampling perspectives. 相似文献
9.
Henrik Baktoft Petr Zajicek Thomas Klefoth Jon C. Svendsen Lene Jacobsen Martin W?ver Pedersen David March Morla Christian Skov Shinnosuke Nakayama Robert Arlinghaus 《PloS one》2015,10(5)
Acoustic positional telemetry systems (APTs) represent a novel approach to study the behaviour of free ranging aquatic animals in the wild at unprecedented detail. System manufactures promise remarkably high temporal and spatial resolution. However, the performance of APTs has rarely been rigorously tested at the level of entire ecosystems. Moreover, the effect of habitat structure on system performance has only been poorly documented. Two APTs were deployed to cover two small lakes and a series of standardized stationary tests were conducted to assess system performance. Furthermore, a number of tow tests were conducted to simulate moving fish. Based on these data, we quantified system performance in terms of data yield, accuracy and precision as a function of structural complexity in relation to vegetation. Mean data yield of the two systems was 40 % (Lake1) and 60 % (Lake2). Average system accuracy (acc) and precision (prec) were Lake1: acc = 3.1 m, prec = 1.1 m; Lake2: acc = 1.0 m, prec = 0.2 m. System performance was negatively affected by structural complexity, i.e., open water habitats yielded far better performance than structurally complex vegetated habitats. Post-processing greatly improved data quality, and sub-meter accuracy and precision were, on average, regularly achieved in Lake2 but remained the exception in the larger and structurally more complex Lake1. Moving transmitters were tracked well by both systems. Whereas overestimation of moved distance is inevitable for stationary transmitters due to accumulation of small tracking errors, moving transmitters can result in both over- and underestimation of distances depending on circumstances. Both deployed APTs were capable of providing high resolution positional data at the scale of entire lakes and are suitable systems to mine the reality of free ranging fish in their natural environment. This opens important opportunities to advance several fields of study such as movement ecology and animal social networks in the wild. It is recommended that thorough performance tests are conducted in any study utilizing APTs. The APTs tested here appear best suited for studies in structurally simple ecosystems or for studying pelagic species. In such situations, the data quality provided by the APTs is exceptionally high. 相似文献
10.
Jessica Laskowski Caitlyn Gillespie Lucia Corral Amy Oden Kent Fricke Joseph J. Fontaine 《Science activities》2013,50(4):147-154
We present a hands-on outdoor activity coupled with classroom discussion to teach students about wildlife habitat selection, the process by which animals choose where to live. By selecting locations or habitats with many benefits (e.g., food, shelter, mates) and few costs (e.g., predators), animals improve their ability to survive and reproduce. Biologists track animal movement using radio telemetry technology to study habitat selection so they can better provide species with habitats that promote population growth. We present a curriculum in which students locate “animals” (transmitters) using radio telemetry equipment and apply math skills (use of fractions and percentages) to assess their “animal's” habitat selection by comparing the availability of habitat types with the proportion of “animals” they find in each habitat type. 相似文献
11.
Francesca Cagnacci Luigi Boitani Roger A. Powell Mark S. Boyce 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2010,365(1550):2157-2162
Global positioning system (GPS) telemetry technology allows us to monitor and to map the details of animal movement, securing vast quantities of such data even for highly cryptic organisms. We envision an exciting synergy between animal ecology and GPS-based radiotelemetry, as for other examples of new technologies stimulating rapid conceptual advances, where research opportunities have been paralleled by technical and analytical challenges. Animal positions provide the elemental unit of movement paths and show where individuals interact with the ecosystems around them. We discuss how knowing where animals go can help scientists in their search for a mechanistic understanding of key concepts of animal ecology, including resource use, home range and dispersal, and population dynamics. It is probable that in the not-so-distant future, intense sampling of movements coupled with detailed information on habitat features at a variety of scales will allow us to represent an animal''s cognitive map of its environment, and the intimate relationship between behaviour and fitness. An extended use of these data over long periods of time and over large spatial scales can provide robust inferences for complex, multi-factorial phenomena, such as meta-analyses of the effects of climate change on animal behaviour and distribution. 相似文献
12.
Development of an automated method of detecting stereotyped feeding events in multisensor data from tagged rorqual whales
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Ann N. Allen Jeremy A. Goldbogen Ari S. Friedlaender John Calambokidis 《Ecology and evolution》2016,6(20):7522-7535
The introduction of animal‐borne, multisensor tags has opened up many opportunities for ecological research, making previously inaccessible species and behaviors observable. The advancement of tag technology and the increasingly widespread use of bio‐logging tags are leading to large volumes of sometimes extremely detailed data. With the increasing quantity and duration of tag deployments, a set of tools needs to be developed to aid in facilitating and standardizing the analysis of movement sensor data. Here, we developed an observation‐based decision tree method to detect feeding events in data from multisensor movement tags attached to fin whales (Balaenoptera physalus). Fin whales exhibit an energetically costly and kinematically complex foraging behavior called lunge feeding, an intermittent ram filtration mechanism. Using this automated system, we identified feeding lunges in 19 fin whales tagged with multisensor tags, during a total of over 100 h of continuously sampled data. Using movement sensor and hydrophone data, the automated lunge detector correctly identified an average of 92.8% of all lunges, with a false‐positive rate of 9.5%. The strong performance of our automated feeding detector demonstrates an effective, straightforward method of activity identification in animal‐borne movement tag data. Our method employs a detection algorithm that utilizes a hierarchy of simple thresholds based on knowledge of observed features of feeding behavior, a technique that is readily modifiable to fit a variety of species and behaviors. Using automated methods to detect behavioral events in tag records will significantly decrease data analysis time and aid in standardizing analysis methods, crucial objectives with the rapidly increasing quantity and variety of on‐animal tag data. Furthermore, our results have implications for next‐generation tag design, especially long‐term tags that can be outfitted with on‐board processing algorithms that automatically detect kinematic events and transmit ethograms via acoustic or satellite telemetry. 相似文献
13.
Geert Aarts Monique MacKenzie Bernie McConnell Mike Fedak Jason Matthiopoulos 《Ecography》2008,31(1):140-160
Management and conservation of populations of animals requires information on where they are, why they are there, and where else they could be. These objectives are typically approached by collecting data on the animals' use of space, relating these positional data to prevailing environmental conditions and employing the resulting statistical models to predict usage at other geographical regions. Technical advances in wildlife telemetry have accomplished manifold increases in the amount and quality of available data, creating the need for a statistical framework that can use them to make population‐level inferences for habitat preference and space‐use. This has been slow‐in‐coming because wildlife telemetry data are spatio‐temporally autocorrelated, often unbalanced, presence‐only observations of behaviourally complex animals, responding to a multitude of cross‐correlated environmental variables. We review the evolution of regression models for the analysis of space‐use and habitat preference and outline the essential features of a framework that emerges naturally from these foundations. This allows us to derive a relationship between usage of points in geographical space and preference of habitats in environmental space. Within this framework, we discuss eight challenges, inherent in the spatial analysis of telemetry data and, for each, we propose solutions that can work in tandem. Specifically, we propose a logistic, mixed‐effects approach that uses generalized additive transformations of the environmental covariates and is fitted to a response data‐set comprising the telemetry and simulated observations, under a case‐control design. We apply this framework to a non‐trivial case‐study using satellite‐tagged grey seals Halichoerus grypus from the east coast of Scotland. We perform model selection by cross‐validation and confront our final model's predictions with telemetry data from the same, as well as different, geographical regions. We conclude that, despite the complex behaviour of the study species, flexible empirical models can capture the environmental relationships that shape population distributions. 相似文献
14.
Eva C. Enders Keith D. Clarke Curtis J. Pennell L. M. Neil Ollerhead David A. Scruton 《Hydrobiologia》2007,582(1):231-242
Winter habitat use and activity patterns of juvenile Atlantic salmon and brown trout were analysed in a comparative study
between Passive Integrated Transponder (PIT) technology, radio telemetry and underwater observation by snorkelling. Two study
periods were conducted in Stoney River, Newfoundland, Canada. During Study period I, 49 juvenile Atlantic salmon (fork length:
11.0–18.0 cm) and 7 brown trout (11.0–17.3 cm) were tagged with PIT tags and/or radio transmitters in late winter of 2004.
During Study period II, 18 juvenile Atlantic salmon (fork length: 12.0–18.4 cm) and 23 brown trout (10.9–20.8 cm) were tagged
and tracked twice a day at 10:00 h and 22:00 h on five consecutive days in late winter of 2005. From the 56 fish released
during Study period I, on average 19.6 ± 6.0% of the PIT tagged fish and 99.3 ± 2.2% of the radio tagged fish were relocated
during any given survey. Over the Study period II, 39% of fish emigrated from the study site. PIT technology had an efficiency
of 39.2 ± 14.1% to detect the remaining fish. In contrast, radio telemetry relocated on average 96.9 ± 6.5% of the tagged
fish whereas by snorkelling on average only 4.1 ± 5.6% of the tagged fish were observed. PIT telemetry may however be more
efficient in smaller, less heterogeneous streams. The advantage of PIT technology over radio telemetry is clearly that it
is relatively less costly permitting higher numbers of individuals to be tagged and there is no limit in the operational life
of the transponder. In winter, juvenile salmonids preferred low flow velocity and no preferences were observed for any specific
water depth over the range of available water depths. Fish selected preferentially boulder habitat over other substrates in
the environment. Habitat utilisation did not differ between day and night. The use of winter preference indices may be important
for future habitat modelling. 相似文献
15.
Karen J. Murchie Emily Schwager Steven J. Cooke Andy J. Danylchuk Sascha E. Danylchuk Tony L. Goldberg Cory D. Suski David P. Philipp 《Environmental Biology of Fishes》2010,89(1):95-104
Fisheries exploitation and habitat alteration are threatening lemon shark (Negaprion bevirostris) populations because they use nearshore regions as nursery sites. As such, there is a need for information on the spatial
ecology of juvenile lemon sharks to identify critical habitats that require protection, as well as to understand their basic
ecology. The purpose of this study was to determine the habitat preferences and movement patterns of juvenile lemon sharks
along a sub-section of coastline characterized by coastal flats and tidal creeks of Eleuthera, The Bahamas. Eleven juvenile
lemon sharks (766 ± 127 mm total length; mean±SD) were captured from various tidal creeks within the 23 km study area and
were surgically implanted with acoustic transmitters. A series of 27 hydrophone receivers acted as a passive monitoring array
to detect tagged individuals as they moved among habitats. Findings suggest that juvenile lemon sharks tagged in this study
prefer shallow water habitats within tidal creeks, and typically display high site fidelity with occasional forays to alternate
habitats or creeks. In fact, more than 90% of tagged lemon sharks had the greatest percentage of detections located at a receiver
at or close to the location where they were tagged. There was no evidence of differences in diel or seasonal movement and
habitat use. Knowledge gained from this study will be useful for directing future conservation and management strategies including
coastal development plans and marine protected areas. 相似文献
16.
Determining the residency of an aquatic species is important but challenging and it remains unclear what is the best sampling methodology. Photo-identification has been used extensively to estimate patterns of animals' residency and is arguably the most common approach, but it may not be the most effective approach in marine environments. To examine this, in 2005, we deployed acoustic transmitters on 22 white sharks (Carcharodon carcharias) in Mossel Bay, South Africa to quantify the probability of detecting these tagged sharks by photo-identification and different deployment strategies of acoustic telemetry equipment. Using the data collected by the different sampling approaches (detections from an acoustic listening station deployed under a chumming vessel versus those from visual sightings and photo-identification), we quantified the methodologies' probability of detection and determined if the sampling approaches, also including an acoustic telemetry array, produce comparable results for patterns of residency. Photo-identification had the lowest probability of detection and underestimated residency. The underestimation is driven by various factors primarily that acoustic telemetry monitors a large area and this reduces the occurrence of false negatives. Therefore, we propose that researchers need to use acoustic telemetry and also continue to develop new sampling approaches as photo-identification techniques are inadequate to determine residency. Using the methods presented in this paper will allow researchers to further refine sampling approaches that enable them to collect more accurate data that will result in better research and more informed management efforts and policy decisions. 相似文献
17.
Frances E. C. Stewart John P. Volpe Jason T. Fisher 《The Journal of wildlife management》2019,83(4):985-992
The use of bait (or attractants) to lure animals to a sampling site is common in wildlife research and important for optimizing species detection rates. The effect of bait on animal movement and space-use, however, is contested, fueled by concerns bait may affect animal movement and increase residency time. If founded, bait may bias parameter estimates from density, species distribution, resource selection, or behavioral models, produce spurious ecological inferences, and skew resulting management recommendations. To test whether animal movement varies with proximity to bait, we used high-resolution global positioning system telemetry data of 10 fishers (Pekania pennanti), temporally paired with 64 baited wildlife camera traps, to quantify the effect of bait on individual and population movement metrics. Although bait appeared to have a significant correlative effect on 1-hour movement segments, landscape characteristics had an effect 1.7 times greater, where the proportion of mixed forest and cultivation explained the majority of variability in animal movements. We contend that maximizing probability of detection and controlling or modeling local-scale landscape variability that could affect the probability of detection is a more important consideration in wildlife research than the effect of bait, which is eclipsed by differences incurred by natural habitat heterogeneity. Failing to maximize the probability of detection may obscure the modest bias potentially presented by the use of bait, or attractants, on ecological inference. © 2019 The Wildlife Society 相似文献
18.
19.
Brent R. Campos Maxfield A. Fish Gardner Jones Rebecca W. Riley Peter J. Allen Peter A. Klimley Joseph J. CechJr John T. Kelly 《Environmental Biology of Fishes》2009,85(1):3-13
Ultrasonic telemetry was used to analyze the effects of environmental variables on movement directions and movement rates
of brown smoothhounds, Mustelus henlei, in Tomales Bay, California. Ultrasonic transmitters were surgically implanted in the peritoneal cavities of one male and
five female brown smoothhounds and tracked during the period of 29 June to 15 July 2004. Coarse-scale tracking consisted of
locating all tagged individuals multiple times during a single session, while fine-scale tracking consisted of following a
single individual continuously during a session. Coarse-scale tracking suggested movement toward the inner bay with incoming
and high tides and toward the outer bay with outgoing and low tides (P = 0.01), whereas the diel cycle had no apparent effect
on their movement directions. Mean shark movement rate was 0.09 m s−1 (range: 0.01–0.34 m s−1), with diel and tidal cycles both having significant effects on their rates of movement (P = 0.02 and P < 0.01), respectively. We tracked two female sharks on a fine scale over three tracking sessions in July 2004. Both individuals
exhibited higher rates of movement during the night compared to the day (P < 0.01). While one shark’s rate of movement was not significantly affected by tidal stage, the other’s was (P < 0.001). 相似文献
20.
Maggie L. E. Boothroyd Tim J. Haxton Charles Hendry Derrick A. Romain Chris C. Wilson Tom Whillans 《Zeitschrift fur angewandte Ichthyologie》2019,35(1):103-116
Species translocations are increasingly being used as a management tool to mitigate population losses due to such factors as habitat degradation and fragmentation, but post‐introduction follow‐up is relatively sparse. Post‐translocation telemetry can assess success by identifying activity, emigrations, survival, habitat usage, and reproductive events, aiding in the continued management of translocated populations and informing future efforts. This study assessed movement of translocated adult lake sturgeon (Acipenser fulvescens) immediately post‐release and a decade later, and tested for associations between environmental variables and spawning movements. Prior to their translocation in 2002, 13 of 51 adult lake sturgeon were surgically implanted with radio telemetry tags and tracked for 1 year. In 2011 and 2013, eight additional adults were captured within the reintroduction site and implanted with radio‐tags. Six of the 13 sturgeon tagged in 2002 dispersed downstream over a dam during the early post‐release period. In spring 2014, tagged adults were tracked to the spillway at the release area's inflow, and spawning was confirmed by larval captures. Movement data for tagged adults differed between the two tracking periods, showing marked differences in behaviour over time. Water velocity was correlated with upstream and downstream spawning movements, with water temperature also correlated with downstream movement. Research regarding post‐translocation movement and dispersal provides insight on behavioural responses following translocation, and may improve outcomes by informing future efforts. 相似文献