首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到10条相似文献,搜索用时 203 毫秒
1.
Gilroy DJ, Jensen OP, Allen BC, Chandra S, Ganzorig B, Hogan Z, Maxted JT, Vander Zanden MJ. Home range and seasonal movement of taimen, Hucho taimen, in Mongolia.
Ecology of Freshwater Fish 2010: 19: 545–554. © 2010 John Wiley & Sons A/S Abstract –  Taimen, Hucho taimen, is the world’s largest salmonid and a prized sport fish. We used radio and acoustic telemetry to characterise movements of adult taimen in an extensive river system, the Eg–Uur, in north‐central Mongolia. Forty‐six taimen were tagged with transmitters (27 radio, 17 acoustic and 2 radio‐acoustic combined) and tracked from 2004 to 2008 using mobile surveys and fixed receivers. The mean home range of individual taimen tracked for an average of 2.4 years was 23 km (N = 41, range = 0.5–93.2 km). Of the fish with over 10 relocations (N = 16), 90% remained within a range of 38 km. Four distinct movement patterns were observed: (i) restricted core home range, (ii) core range with seasonal departures, (iii) core range with separate seasonal range and (iv) home range transfer. Movement was greatest in May and June (spawning and postspawning period) with another peak period of movement in September and October (water temperature cooling).  相似文献   

2.
Zimmer M, Schreer JF, Power M. Seasonal movement patterns of Credit River brown trout (Salmo trutta).
Ecology of Freshwater Fish 2010: 19: 290–299. © 2010 John Wiley & Sons A/S Abstract – Movement habits in riverine populations of brown trout vary among watersheds. Thus it is important to identify factors influencing differences in individual behaviour so as to improve the information resource base available for the design of river‐specific management strategies. Such information is particularly needed in the rapidly urbanising watersheds of eastern North America where relatively little is known about anthropogenic influences on brown trout populations. In this study, we examined the influence of water temperature on brown trout behaviour in the Credit River in south‐central Ontario, Canada with respect to seasonal movement patterns. Observed patterns of movement were also correlated with variations in river discharge and habitat quality. Forty‐three radio‐tagged, adult brown trout were tracked in a confined 39.8 km portion of the Credit River from 15 May 2002 to 28 July 2003. Fish were captured in three sections of the river that differed in distance downstream and habitat quality. Fish size had little impact on movement patterns. However, there was considerable variation in seasonal movement with upstream movements to summer positions, maintenance of summer positions, downstream and often extensive movements in fall. Also observed was maintenance of winter positions and repeated upstream movements in late spring‐early summer to previously used summer positions. The elaborate movement behaviour in the Credit River population was attributed to seasonal changes in thermal habitat quality. Fish tagged in less suitable thermal habitats moved significantly more than fish from more suitable thermal habitats.  相似文献   

3.
We investigated the summer ecology of juvenile steelhead trout Onchorhynchus mykiss and Chinook salmon O. tshawytscha in the context of habitat use and movement behaviour. The study area was a 14.8 km section of the Chehalis River, Washington, and is of particular interest due to recent proposals for both a flood retention dam and restoration actions in this watershed. Ten study reaches were paired in distance upstream and downstream from a central point where a passive integrated transponder antenna array was operated between late June and September 2014. Juvenile densities for each species were associated with reach‐scale habitat and temperature characteristics. Juvenile steelhead underwent upstream and downstream movements up to 7 km, although more fish from further away moved downstream than upstream. Juvenile steelhead repeated horizontal movements throughout the study period, but daily detections were not associated with temperature or flow. The majority (81%) of steelhead movements occurred between the hours of 04:00–07:00 and 18:00–21:00. Juvenile Chinook underwent a downstream migration that was nearly complete by the end of August. Most juvenile Chinook were detected just once and movements occurred on days with warmer stream temperature and higher flows. The majority of Chinook movements occurred at night. Although juvenile salmonids are often thought to have small home ranges during summer months, our results suggest that horizontal movements may be more prevalent than previously thought. Summer habitat should be defined by a network of suitable rearing reaches with connectivity available in both upstream and downstream directions.  相似文献   

4.
Beatty SJ, Morgan DL, McAleer FJ, Ramsay AR. Groundwater contribution to baseflow maintains habitat connectivity for Tandanus bostocki (Teleostei: Plotosidae) in a south‐western Australian river.
Ecology of Freshwater Fish 2010: 19: 595–608. © 2010 John Wiley & Sons A/S Abstract – A global biodiversity hotspot, south‐western Australia is characterised by a highly endemic freshwater fish fauna that is severely impacted by habitat alterations. As is the case with many rivers in this region, the Blackwood River is secondarily salinised as a consequence of agricultural practices and this has caused population depletions of halo‐intolerant fishes. This study is the first to examine the role that groundwater intrusion has in maintaining habitat connectivity for an obligate freshwater fish in a secondarily salinised river. We determined the significance of nonsaline groundwater intrusion in maintaining habitat and migratory routes of the freshwater cobbler, Tandanus bostocki during prolonged annual dry periods; characteristic of Mediterranean climatic zones. Tandanus bostocki undertook large, yet spatially and temporally variable, localised movements through riffles. During baseflow, the period of major groundwater influence, movements were significantly associated with discharge. Analysis of gonadal development suggested that such movements were not strictly related to reproduction and were probably for foraging purposes. The study reveals groundwater is crucial in maintaining migratory routes through riffles and suggests T. bostocki may be reliably used as an indicator of aquatic habitat connectivity in light of groundwater extractions and also continued rainfall reductions in this region due to climate change.  相似文献   

5.
  1. Reservoirs and associated river fragments are novel ecosystems not experienced by fishes in their evolutionary history, yet they are now commonplace across the globe. Understanding how fishes use these novel habitats is vital to conservation efforts in contemporary riverscapes.
  2. Movement patterns of the endangered razorback sucker (Xyrauchen texanus) synthesized from tagging efforts in the upper Colorado River basin, USA, illustrate the applications of tagging technology and data sharing by multiple agencies to better understand the spatial ecology of large river fishes.
  3. Tagging studies between 2014 and 2018 in Lake Powell and its two main tributary rivers, the Colorado (unfragmented) and San Juan (waterfall‐fragmented), were used to quantify movement of razorback sucker within this river–reservoir habitat complex. In addition, facilitated translocations of fish upstream of a waterfall barrier in the San Juan River were assessed in 2016–2017.
  4. Extensive movement of fish occurred within and across river and reservoir habitats. Of 722 fish captured in the Colorado River arm of Lake Powell, 36% of re‐encounters occurred upstream in the Colorado or Green rivers, or fish dispersed through the reservoir and were detected in the San Juan River arm. Fourteen fish moved more than 600 km. In the San Juan arm of the reservoir, 29% and 20% of fish in 2017 and 2018, respectively, had moved ~30–40 km upstream below the waterfall in the San Juan River within a year. In 2016–2017, 303 fish were translocated upstream of the waterfall into the San Juan River, but 80% were re‐encountered downstream of the waterfall within a year.
  5. Long‐distance movements by razorback sucker were common within and among rivers and reservoirs illustrating how large river fish, in general, might maintain population connectivity in highly altered ecosystems.
  相似文献   

6.
The mobility patterns of two native species, barbel, Barbus barbus (L.) and chub, Squalius cephalus (L.), and of one non‐native fish species, the catfish Silurus glanis (L.), were assessed on a 35.5‐km reach of the Upper Rhône River, a strong flowing river with notable thermal regime alterations. An active acoustic tracking technique adapted to large rivers allowed (1) the identification of longitudinal home ranges, movements and preferred habitat at large scale, and (2) the analysis of the influence of discharge and water temperature on the movement patterns of the fish. The active fish‐tracking system recorded 1,572 fish localisations over 7 months on a weekly basis for 80% of the tagged fish (37 barbel, 23 chub and 13 catfish). Compared with the catfish, barbel and chub showed wider longitudinal home ranges, more movements >1 km and higher interindividual variability. The catfish preferred artificially heated habitats with less morphological diversity. The three species were more often localised in river sections with high density of woody debris. The results suggest that habitat degradation is more damaging for cyprinids in large modified rivers, while the catfish seemed less, impacted.  相似文献   

7.
Movement of fishes through space and time is critical for population regulation and community structuring, but the dispersal of many benthic stream fishes remains unstudied. We used passive integrated transponders to track the short‐term dispersal of 51 banded sculpin Cottus carolinae throughout a 600 m reach of Little Creek in central Tennessee during April and May. Our objectives were to assess the efficacy of recently developed dispersal models, evaluate temporal variability in movement and determine whether individuals switched between stationary and mobile movement behaviours. Observed movement distances did not differ from modelled leptokurtic dispersal kernels estimated using the fishmove package in the R Statistical Environment for 12 of 13 recapture occasions. Leptokurtic dispersal kernel parameters including the mobile component (σmob) and shared stationary component (p) were temporally dynamic and differed from static median values reported for fishes in fishmove, while the more abundant stationary component (σstat) showed agreement with fishmove. The recapture occasion during which model predictions were not validated was associated with a large flow pulse that stimulated increased movement at the population scale. At the individual scale, 28 of 51 fish switched between stationary and mobile dispersal behaviour and the frequency distribution of switches was leptokurtic. Collectively, our findings reveal an emergent property characterised by consistent upstream movement of banded sculpin despite variability in population‐scale responses to flow and individual‐scale switches in movement behaviour. This paradox represents the march of the sculpin, in which fish diffusively spread upstream at a constant rate despite multiscale variability in movement behaviours.  相似文献   

8.
The availability of water is becoming more variable as flow regime alterations intensify both locally and on a global scale. This pattern has been observed in the tributaries of the central Chattahoochee River System as water withdrawal and natural drought have caused flows to diminish. Stream discharge has steadily decreased in the study area by 31% over the last 50 years, and during this time, fish assemblage homogenization has occurred throughout the system. Our primary objective was to assess whether spawning mode and water availability are catalysts for fish assemblage change in tributaries of the Chattahoochee River System. We found that species which prefer or have adapted to low flow conditions (e.g. blacktail shiner Cyprinella venusta, redbreast sunfish Lepomis auritus and blackbanded darter Percina nigrofasciata) are becoming dominant and replacing historically dominant fluvial specialists. When examining short‐term changes between a dry year (2009) and a wet year (2010), some species preferring higher flows such as the highscale shiner Notropis hypsilepis were detected during the wet year, suggesting that the amount of water is important for the presence of these species in upstream reaches where they were historically abundant. Species that can reproduce successfully in low flow conditions are thriving and expanding their native ranges as more habitat becomes suitable. Species that require higher flows for part of their life cycle, however, appear to be declining from upstream areas as water availability continues to decrease, despite temporary recovery from downstream refugia during wet years.  相似文献   

9.
Smallmouth bass, Micropterus dolomieu Lacepède, movement dynamics were investigated in a connected mainstem river‐tributary system. Smallmouth bass moved large distances annually (n = 84 fish, average = 24.6 ± 25.9 km, range = 0.03 to 118 km) and had three peak movement periods (pre‐spawn, post‐spawn and overwintering). Movement into and out of tributaries was common, but the movement between mainstem river and tributary habitats varied among tagging locations and season. In general, a large proportion of fish that were tagged in tributaries moved out of the tributaries after spawning (22/30 fish). Because of the importance of fish movement patterns on population dynamics, the observed individual variability in movement, quantified using a hierarchical model, and the potential for long‐distance movements are important considerations for smallmouth bass conservation and management. In addition, mainstem river‐tributary connectivity appears to play an important role for smallmouth bass during key life history events.  相似文献   

10.
Abstract –  This article reports on the findings of a study undertaken within the Murray-Darling River Basin in southeastern Australia, which investigated the impact of weirs on downstream fish movement. Downstream fish movement was monitored at Kennedy's Weir (an overshot, 2 m high weir) on the Broken Creek and Torrumbarry Weir (an undershot, 6.5 m high weir) on the Murray River. A trap used to sample Kennedy's Weir indicated that fish travelled downstream over this weir without sustaining injury or death. A follow-up study, whereby fish were captured below the two respective weirs and translocated upstream where they were radio tagged and released, indicated that while a few fish travelled downstream past the weirs on their return movements back to their home range areas, most were reluctant to do so. This study demonstrates that low-level weirs may inhibit downstream fish movement, and enhancement of downstream fish passage for potamodromous fish species warrants further investigation.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号