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1.
Helga Guderley Brigitte A. Lavoie Nicole Dubois 《Fish physiology and biochemistry》1994,13(5):419-431
Thermal acclimation may directly modify muscle metabolic capacities, or may modify them indirectly via effects upon physiological processes such as growth, reproduction or senescence. To evaluate these interacting effects, we
examined the influence of thermal acclimation and acclimatization upon muscle metabolic capacities and tissue masses in 1
+ stickleback, Gasterosteus aculeatus, in which confounding interactions between temperature and senescense should be absent. Furthermore, we examined the influence
of thermal acclimation upon individual growth rate, muscle enzyme levels and tissue masses in 2 + stickleback sampled at the
beginning of their final reproductive season. For 1 + stickleback, cold acclimation more than doubles mitochondrial enzyme
levels in the axial muscle. Thermal acclimation did not change the condition of 1 + stickleback at feeding levels which could
not maintain the condition of 2+ stickleback. Compensatory metabolic responses to temperature were not apparent in field acclimatized
1 + stickleback. The growth rate of 2 + stickleback was markedly affected by temperature: warm-acclimated fish generally lost
mass even at very high levels of feeding (up to 78 enchytraid worms per day) while cold-acclimated fish gained mass. This
suggests that warm temperatures accelerate the senescence of 2 + stickleback. Generally, muscle enzyme activities increased
with growth rate. In axial muscle, the relationships between CS activity and growth rate differed with acclimation temperature.
Independent of the influence of growth rate, CS activities were consistently higher in cold- than warm-acclimated 2 + stickleback,
suggesting compensatory increases of CS activity with cold acclimation.
Corresponding author; This paper is dedicated to the memory of Gerry J. FitzGerald who passed away on March 14, 1994. 相似文献
2.
Three-spined stickleback Gasterosteus aculeatus, males were implanted with Silastic capsules filled with different aromatase
inhibitors; 1,4,6-androstatriene-3,17-dione or the non-steroidal CGS16949 A, 4-(5,6,7,8-tetrahydrimidazol [1,5-a]pyridin-5-yl)
benzonitrile monohydrochloride or empty capsules. The fish were then exposed to long or short photoperiod. Under the long
photoperiod most fish in all treatments displayed a hypertrophied kidney (a secondary sexual character in sticklebacks) and
completed, quiescent spermatogenesis, similar as in the natural spawning period. Under the short photoperiod the controls
had unstimulated kidneys and an active spermatogenesis, whereas the males implanted with both aromatase inhibitors had stimulated
kidneys, though not to the extent as in the long photoperiod, and completed, quiescent spermatogenesis. These findings suggest
that aromatization is of importance for the inhibitory effects of short photoperiod on reproduction in the stickleback.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
3.
The temporal dynamics of appetite (weight of food consumed per day) were analysed for fish fed to satiation after a 1 or 2-week period of feed deprivation. Three species were compared: two omnivores (minnow, Phoxinus phoxinus and gibel carp, Carassius auratus gibelio) and a carnivore (three-spined stickleback, Gasterosteus aculeatus). All species showed compensatory changes in appetite and growth during the re-feeding period but in the stickleback, there was a lag of a week before the compensatory response was detected. The temporal dynamics of appetite differed between the three species but not within a species. Appetite of the minnow declined towards control levels from the onset of re-feeding. In gibel carp, appetite increased to a peak and then declined to control levels. In the stickleback, appetite was initially below control levels, increased to a maximum, then declined towards control levels. The differences between the species might have been artefacts of the experimental protocols used but could also reflect underlying differences in the control of appetite in these species of fish. 相似文献
4.
Abstract – Threespine stickleback ( Gasterosteus aculeatus ) samples from Prator Lake in southcentral Alaska consist of the relatively rare form of weakly armoured individuals with few lateral plates and no pelvic spines. Prator Lake has been sampled for threespine stickleback since 1983. Exotic northern pike ( Esox lucius ) were first observed in this lake in 1996. The appearance of pike corresponds with a dramatic decrease in stickleback numbers and apparent local extinction. The stickleback population may have been vulnerable to an exotic predator because Prator Lake lacks native piscivorous fishes, and this population had extreme armour reduction. 相似文献
5.
R. J. Wootton 《水产资源保护:海洋与淡水生态系统》2010,20(4):365-370
- 1. Abundance of a population of three‐spined stickleback, Gasterosteus aculeatus L., in a small backwater of Afon Rheidol in mid‐Wales (UK) was estimated annually each October from 1972 to 1999 by mark–recapture.
- 2. The population became extinct in 2000, because of land‐use changes in 1995, which modified the drainage pattern through the backwater, causing the backwater to eventually dry up.
- 3. The final decline to extinction started from an estimated abundance of 1550 in 1998 and the abundance in 1999, the year before extinction, was 85. The smallest abundance from which the population showed an increase was 670.
- 4. Two years before extinction (1998), the population was characterized by an anomalously high proportion of small fish.
- 5. There was a significant power relationship between the years to extinction and population size, but if the data were analysed in two periods, 1972–1989 and 1990–1999, the relationship was only significant for the second period.
- 6. There was no relationship between time to extinction and per capita annual rate of increase (k), although values of k were unusually low in the last two years before extinction.
- 7. Time to extinction was not related to mean length, mean mass or the condition of the fish.
- 8. The results suggest that the indicators of impending extinction may vary with the causes of extinction and may be ambiguous, even when a long time‐series of demographic data is available. Copyright © 2010 John Wiley & Sons, Ltd.
6.
Trophic pathways supporting Arctic grayling in a small stream on the Arctic Coastal Plain,Alaska 
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下载免费PDF全文 Beaded streams are prominent across the Arctic Coastal Plain (ACP) of Alaska, yet prey flow and food web dynamics supporting fish inhabiting these streams are poorly understood. Arctic grayling (Thymallus arcticus) are a widely distributed upper‐level consumer on the ACP and migrate into beaded streams to forage during the short 3‐month open‐water season. We investigated energy pathways and key prey resources that support grayling in a representative beaded stream, Crea Creek. We measured terrestrial invertebrates entering the stream from predominant riparian vegetation types, prey types supporting a range of fish size classes, and how riparian plants and fish size influenced foraging habits. We found that riparian plants influenced the quantity of terrestrial invertebrates entering Crea Creek; however, these differences were not reflected in fish diets. Prey type and size ingested varied with grayling size and season. Small grayling (<15 cm fork length (FL)) consumed mostly aquatic invertebrates early in the summer, and terrestrial invertebrates later in summer, while larger fish (>15 cm FL) foraged most heavily on ninespine stickleback (Pungitius pungitius) throughout the summer, indicating that grayling can be insectivorous and piscivorous, depending on size. These findings underscore the potential importance of small streams in Arctic ecosystems as key summer foraging habitats for fish. Understanding trophic pathways supporting stream fishes in these systems will help interpret whether and how petroleum development and climate change may affect energy flow and stream productivity, terrestrial–aquatic linkages and fishes in Arctic ecosystems. 相似文献
7.
Gagné N Mackinnon AM Boston L Souter B Cook-Versloot M Griffiths S Olivier G 《Journal of fish diseases》2007,30(4):213-223
Viral haemorrhagic septicaemia virus (VHSV) was isolated from mortalities occurring in populations of mummichog, Fundulus heteroclitus, stickleback, Gasterosteus aculeatus aculeatus, brown trout, Salmo trutta, and striped bass, Morone saxatilis, in New Brunswick and Nova Scotia, Canada. The isolated viral strains produced a cytopathic effect on the epithelioma papillosum cyprini cell line. Serum neutralization indicated the virus was VHSV and sequencing identified the rhabdovirus isolates as the North American strain of VHSV. Phylogenetic analysis indicated that the isolates are closely related and form a distinguishable subgroup of North American type VHSV. To our knowledge, this is the first report of VHSV in mummichog and striped bass. 相似文献
8.
S. Sánchez-Gonzáles G. Ruiz-Campos S. Contreras-Balderas 《Ecology of Freshwater Fish》2001,10(4):191-197
Abstract – The feeding ecology and habitat of the threespine stickleback ( Gasterosteus aculeatus microcephalus Girard, 1854) was studied from November 1996 to May 1997 in a remnant population of northwestern Baja California, México. The analysis of the stomach content of 179 individuals (25 to 56 mm standard length [SL]) showed a diet dominated by cyclopoid copepods (43.8%) and chironomid larvae (39.1%). Diet in relation to size and sex of the fish was dominated by copepods in autumn and winter and by chironomid larvae during spring. Diet overlap (Schoener's index) was significant (≥60%) between fish size-classes in January, March and April and between sexes for most sampling months. The average size of prey consumed was independent of fish mouth size. The feeding strategy of the threespine stickleback shifted from opportunist in winter to specialist in spring. 相似文献
9.
Abstract – The life history traits of breeding size, clutch size, egg size and relative clutch mass were examined for evidence of plasticity within a set of six annual samples of threespine stickleback, Gasterosteus aculeatus L., females from south-central Alaska, USA. Three samples (from 1992, 1996 and 1999) were of stickleback native to, and living within, a stream environment, while three (from 1995, 1996 and 1999) represented fish living within a pond environment recently colonized by the stream stickleback. Significant differences between stream and pond fish were found for all four traits. For most traits, pond-living females showed greater variation both across and within years than did stream-living females. Although extremely rapid evolution within the pond, or genetic drift caused by low founding population size, could not be completely ruled out, trait changes across years in both environments were interpreted as representing adaptive plasticity. 相似文献
10.
Modelling historical mesocosm data: Application of a fish bioenergetics model in semi‐natural conditions 下载免费PDF全文
下载免费PDF全文 Viviane David Benoit Goussen Cleo Tebby Sandrine Joachim Jean‐Marc Porcher Rémy Beaudouin 《Ecology of Freshwater Fish》2018,27(4):1101-1113
Developing ecological models for accurately predicting the dynamics of a population and individual physiological processes in field conditions is a challenging task for ecosystem management and ecological risk assessment. Here, we propose to assess the relevance of a dynamic energy budget (DEB) model calibrated using data previously generated from laboratory experiments for adult three‐spined sticklebacks (Gasterosteus aculeatus) living in semi‐natural conditions. We compared different ways of integrating different data sets such as temperature and prey abundance obtained in mesocosm experiments to assess the predictive capacity of the model. By this study, we provide recommendations for developing an appropriate environmental scenario (e.g. natural variations of food and temperature) for using a DEB model in a field context. We conclude that a DEB model calibrated with laboratory data can be used to predict the physiological processes of an organism living in semi‐natural conditions, but that the reproductive behaviour of the organism can affect the predictions. At last, we suggest that further studies on the feeding behaviour may be necessary for immature organisms. 相似文献