scholarly journals Do juvenile Atlantic salmon (Salmo salar) use chemosensory cues to detect and avoid risky habitats in the wild?

2011 ◽  
Vol 68 (4) ◽  
pp. 655-662 ◽  
Author(s):  
Jae-Woo Kim ◽  
James W.A. Grant ◽  
Grant E. Brown
Keyword(s):  
Atlantic Salmon ◽  
Salmo Salar ◽  
Stream Water ◽  
Alarm Cues ◽  
Alarm Cue ◽  
Atlantic Salmon Salmo Salar ◽  
Juvenile Atlantic Salmon ◽  
Chemical Alarm Cues ◽  
In The Wild ◽  
Experimental Treatments

We examined whether juvenile Atlantic salmon ( Salmo salar ) in the wild adjust their behaviour in response to chemical cues of predator activity during a 4-week period after emergence from gravel nests. In each of seven 75 m2 sites in Catamaran Brook, New Brunswick, Canada, we established three contiguous sections differing in perceived predator activity by releasing stream water in control sections, conspecific alarm cues in risky sections, and nothing in buffer sections in both 2006 and 2007. As predicted, the density of young-of-the-year (YOY) salmon tended to decrease in alarm cue sections, while it increased in control and buffer sections. After the 2-week manipulation in 2006, we switched treatments so that buffer sections became alarm cue sections and alarm cue sections became buffer sections for an additional 2-week period. After the switch, the number of YOY increased least in the new alarm cue sections and most in control and new buffer sections. In contrast with YOY, the density of age 1+ parr was not affected by the experimental treatments. Our results suggest that YOY salmon can use chemical alarm cues to assess the predator activity of habitats in the wild.

Predation costs of impaired chemosensory risk assessment on acid-impacted juvenile Atlantic salmon (Salmo salar)

2014 ◽  
Vol 71 (5) ◽  
pp. 756-762 ◽  
Author(s):  
Chris K. Elvidge ◽  
Grant E. Brown
Keyword(s):  
Risk Assessment ◽  
Atlantic Salmon ◽  
Salmo Salar ◽  
Brook Trout ◽  
Predatory Fish ◽  
Alarm Cues ◽  
Compensatory Mechanisms ◽  
Atlantic Salmon Salmo Salar ◽  
Juvenile Atlantic Salmon ◽  
Chemical Alarm Cues

Weak levels of acidification (pH < 6.6) inhibit the ability of fishes to assess predation risk via interference with damage-released chemical alarm cues. While survival benefits associated with behavioural responses to alarm cues have been demonstrated under laboratory conditions, it remains largely unknown whether fishes under natural conditions experience similar benefits. Using hatchery-reared juvenile Atlantic salmon (Salmo salar) as a model organism, we conducted a tethering experiment in reaches of neutral (pH ≥ 6.6) and acidic (pH < 6.6) salmon nursery streams, plus one additional stream that varied between pH classes. Despite exposure to fewer predatory fish species, similar availability of physical refugia, and similar threat from terrestrial predators, tethered fish in acidic streams were significantly more likely to be predated over the course of a trial than their counterparts in neutral streams. These results suggest that (i) in the absence of compensatory mechanisms, juvenile Atlantic salmon under acidic conditions may experience greater rates of predation as a result of impaired chemosensory risk assessment, and (ii) brook trout (Salvelinus fontinalis) appear to play the greatest role in limiting the survival of young-of-the-year (0+) salmon.

Effects of acid rainfall on juvenile Atlantic salmon (Salmo salar) antipredator behaviour: loss of chemical alarm function and potential survival consequences during predation

2009 ◽  
Vol 60 (12) ◽  
pp. 1223 ◽  
Author(s):  
Antoine O. H. C. Leduc ◽  
Ellie Roh ◽  
Grant E. Brown
Keyword(s):  
Rainbow Trout ◽  
Atlantic Salmon ◽  
Salmo Salar ◽  
Antipredator Behaviour ◽  
Chemical Information ◽  
Alarm Cues ◽  
Episodic Acidification ◽  
Atlantic Salmon Salmo Salar ◽  
Juvenile Atlantic Salmon ◽  
Chemical Alarm Cues

Many organisms rely on chemosensory cues to mediate predation risks. Recent studies have demonstrated impaired chemosensory detection ability under weak acidification. Because rainfall may lead to episodic acidification of surface water, we assessed the effects of acid rain on chemosensory alarm functions. Under natural conditions, we quantified alarm behaviour of juvenile Atlantic salmon (Salmo salar) exposed to conspecific chemical alarm cues before and following rainfall. Before rainfall, salmon were capable of an alarm response in the study streams. After rainfall, salmon from Devil’s Brook did not respond to the alarm cues whereas the detection of salmon from Catamaran Brook (a comparable stream having higher acid neutralising capacity) was maintained. To relate these findings to predator–prey encounters, we performed a second experiment where we staged encounters between prey (rainbow trout, Oncorhynchus mykiss) and predator (largemouth bass, Micropterus salmoides) exposed to acidified and unacidified rainbow trout chemical alarm cues. Trout exposed to acidified alarm cues survived for a significantly shorter amount of time than trout exposed to unacidified alarm cues, whereas no difference in overall predator behaviour was observed. Our results suggest that episodic acidification in small nursery streams may disrupt the chemical information mediated by the chemical alarm cues that can translate into higher survival costs for prey.

scholarly journals Impaired detection of chemical alarm cues by juvenile wild Atlantic salmon (Salmo salar) in a weakly acidic environment

2006 ◽  
Vol 63 (10) ◽  
pp. 2356-2363 ◽  
Author(s):  
Antoine Olivier Henri Claude Leduc ◽  
Ellie Roh ◽  
Mark Charles Harvey ◽  
Grant Edwin Brown
Keyword(s):  
Atlantic Salmon ◽  
Salmo Salar ◽  
Alarm Cues ◽  
Multiple Streams ◽  
Age Classes ◽  
Atlantic Salmon Salmo Salar ◽  
Chemical Alarm Cues ◽  
Young Of The Year ◽  
Single Field ◽  
Acidity Level

Many prey fishes rely on damage-released chemical alarm cues to detect and avoid predators. The ability to use these cues has been shown to confer considerable survival benefits to individuals. While several laboratory studies and a single field study have demonstrated that an ambient pH of 6.0 impairs fishes in their ability to detect these alarm cues, no study had yet compared the response to alarm cue exposures across populations residing in multiple streams of a different acidity level. In our study, we conducted live behavioural observations in five nursery streams, ranging in pH from 5.71 to 7.49 on two age classes (young of the year and parr) of wild juvenile Atlantic salmon (Salmo salar). We aimed to assess if the detection of these chemical alarm cues was constantly dependant on the ambient pH or if variations in the detection occurred among populations of the different streams regardless of the ambient acidity level. Our results demonstrated that salmon present in any acidic stream did not respond to alarm cues, while those in neutral streams exhibited typical alarm responses.

Differences in antipredator behaviour between wild and hatchery-reared juvenile Atlantic salmon (Salmo salar) under seminatural conditions

2011 ◽  
Vol 68 (12) ◽  
pp. 2157-2166 ◽  
Author(s):  
Christopher D. Jackson ◽  
Grant E. Brown
Keyword(s):  
Atlantic Salmon ◽  
Salmo Salar ◽  
Antipredator Behaviour ◽  
Source Population ◽  
Alarm Cues ◽  
Natural Conditions ◽  
Atlantic Salmon Salmo Salar ◽  
Chemical Alarm Cues ◽  
Two Generations ◽  
Differential Experience

Captive rearing may elicit experiential or genetically based changes to salmonid antipredator behaviour, which may reduce survival of hatchery-reared fishes when they are released into the wild. Nevertheless, few studies have compared the behaviour between local wild-caught and local hatchery-reared fish (two generations or less), and none have done so under natural conditions. We conducted a seminatural field study comparing the antipredator behaviour of wild-caught, F1 (offspring of wild-caught adults) with that of F2 (second generation) hatchery-reared young-of-the-year Atlantic salmon ( Salmo salar , from the same source population) in response to standardized chemical alarm cues. Wild-caught salmon exhibited the strongest antipredator response to a standardized threat (conspecific alarm cues), while F2 salmon exhibited the weakest response. F1 salmon were intermediate in their behavioural response. The observed differences between wild-caught and F1 salmon suggests that differential experience may play a significant role in predator avoidance behaviours. Furthermore, the observed differences between F1 and F2 salmon suggests that even one full generation of hatchery rearing may be sufficient to select for maladaptive responses to predators under natural conditions. Given the controversy regarding the effectiveness of hatchery programs for conservation use, the results of this study suggest that minimizing hatchery time may reduce the behavioural differences between wild and hatchery-reared fishes.

scholarly journals Sulphated glycosaminoglycans and proteoglycans in the developing vertebral column of juvenile Atlantic salmon (Salmo salar)

2015 ◽  
Vol 41 (4) ◽  
pp. 1029-1051 ◽  
Author(s):  
Kirsten O. Hannesson ◽  
Elisabeth Ytteborg ◽  
Harald Takle ◽  
Grethe Enersen ◽  
Grete Bæverfjord ◽  
...  
Keyword(s):  
Atlantic Salmon ◽  
Salmo Salar ◽  
Vertebral Column ◽  
Atlantic Salmon Salmo Salar ◽  
Juvenile Atlantic Salmon ◽  
Sulphated Glycosaminoglycans

Effect of time of day, time of year, and life history strategy on time budgeting in juvenile Atlantic salmon, Salmo salar

1999 ◽  
Vol 56 (12) ◽  
pp. 2397-2403 ◽  
Author(s):  
Sveinn K Valdimarsson ◽  
Neil B Metcalfe
Keyword(s):  
Life History ◽  
Atlantic Salmon ◽  
Salmo Salar ◽  
Life History Strategy ◽  
Time Of Day ◽  
Life History Strategies ◽  
Foraging Efficiency ◽  
Atlantic Salmon Salmo Salar ◽  
Juvenile Atlantic Salmon ◽  
Time Of Year

Traditionally, behavioural studies on juvenile Atlantic salmon, Salmo salar, have been conducted during the day in summer. It is known that Atlantic salmon become nocturnal in winter, but very little is known about their behaviour at that time. Therefore, observations in a seminatural stream were carried out during the day and night, from February to June, comparing diel and seasonal differences in behaviour between fish adopting alternative life history strategies. The results showed a general trend for more activity in spring than in winter, and the fish were found to be foraging at surprisingly low light levels. There were differences in relative feeding rate between the life history strategies; the early migrant fish foraged mostly during the day whereas the delayed migrant fish did more foraging at night. There is some evidence that the early migrant fish made fewer feeding attempts over the winter, which is surprising, since they grow faster over that period. This suggests differences in foraging efficiency, which could contribute to the separation into these two life history strategies.

Sign in / Sign up

Export Citation Format

Share Document