Does habitat complexity influence the ability of fathead minnows to learn heterospecific chemical alarm cues?

2003 ◽  
Vol 81 (5) ◽  
pp. 923-927 ◽  
Author(s):  
M S Pollock ◽  
D P Chivers

Numerous aquatic animals release chemical cues when attacked by a predator. These cues "warn" other individuals of danger and have been termed alarm cues. Cross-species responses to alarm cues are common and in some cases result from learned recognition. However, little is known about the ecological factors that could influence this learned recognition. The current study focuses on the role of habitat complexity in the learning of heterospecific alarm cues. We introduced brook stickleback (Culaea inconstans) into outdoor pools containing fathead minnows (Pimephales promelas) naïve to stickleback. The pools all contained a predatory fish (northern pike, Esox lucius) but varied in habitat characteristics. Pools representing high-complexity habitats had a large amount of structure to obscure the visual environment, while pools representing low-complexity habitats had minimal structure. After 8 days, fish were removed from the pools and behavioural assays were conducted in the laboratory. We tested the minnows for a response to either stickleback skin extract (experimental) or swordtail (Xiphophorus helleri) skin extract (control) and found that minnows conditioned in pools with little structure had learned to recognize stickleback alarm cues, while those from pools with complex structure did not recognize stickleback alarm cues.


Behaviour ◽  
2002 ◽  
Vol 139 (7) ◽  
pp. 929-938 ◽  
Author(s):  
Douglas Chivers ◽  
Reehan Mirza ◽  
Jeffery Johnston

AbstractNumerous species of aquatic animals release chemical cues when attacked by a predator. These chemicals serve to warn other conspecifics, and in some cases heterospecifics, of danger, and hence have been termed alarm cues. Responses of animals to alarm cues produced by other species often need to be learned, yet mechanisms of learned recognition of heterospecific cues are not well understood. In this study, we tested whether fathead minnows (Pimephales promelas) could learn to recognize a heterospecific alarm cue when it was combined with conspecific alarm cue in the diet of a predator. We exposed fathead minnows to chemical stimuli collected from rainbow trout, Oncorhynchus mykiss, fed a mixed diet of minnows and brook stickleback, Culaea inconstans, or trout fed a mixed diet of swordtails, Xiphophorous helleri, and stickleback. To test if the minnows had acquired recognition of the heterospecific alarm cues, we exposed them to stickleback alarm cues and introduced an unknown predator, yellow perch (Perca flavescens) or northern pike (Esox lucius). Both perch and pike took longer to initiate an attack on minnows that were previously exposed to trout fed minnows and stickleback than those previously exposed to trout fed swordtails and stickleback. These results demonstrate that minnows can learn to recognize heterospecific alarm cues based on detecting the heterospecific cue in combination with minnow alarm cues in the diet of the predator. Ours is the first study to demonstrate that behavioural responses to heterospecific chemical alarm cues decreases the probability that the prey will be attacked and captured during an encounter with a predator.



Behaviour ◽  
2008 ◽  
Vol 145 (3) ◽  
pp. 391-407 ◽  
Author(s):  
Brian Wisenden

AbstractChemical cues released from injured fish skin during a predator attack provide reliable information about the presence of predation risk. Here, I report estimates of the area avoided by littoral fishes after experimental release of chemical alarm cues in two small lakes in northern Minnesota. Minnow traps were labeled chemically with either water (control) or skin extract (chemical alarm cue) made from 2 cm2 of cyprinid skin (redbelly dace in experiment 1, fathead minnows in experiment 2). Traps labeled with water were placed 1, 2, or 8 m from traps labeled with alarm cue. After 2 h, water-traps that were either 1 or 2 m distant from an alarm-trap caught significantly fewer fish than water-traps 8 m distant from alarm-traps. Conspecific and heterospecific skin extract produced similar area avoidance by fathead minnows. Redbelly dace showed a larger active space in response to conspecific than heterospecific alarm cues. Brook stickleback showed reduced catches within 2 m of skin extract of fathead minnows. Overall, the radius of active space was between 2 and 8 m under lake conditions with average subsurface currents of 0.82 cm/s. These data are the first field estimates of active space of ostariophysan chemical alarm cues.



Ethology ◽  
2006 ◽  
Vol 112 (8) ◽  
pp. 801-806 ◽  
Author(s):  
M. S. Pollock ◽  
R. J. Pollock ◽  
D. P. Chivers


1976 ◽  
Vol 54 (12) ◽  
pp. 2230-2231 ◽  
Author(s):  
R. J. F. Smith

In laboratory and field tests, breeding male fathead minnows respond to conspecific skin extract with a fright reaction despite their own seasonal loss of alarm substance cells. Their fright reaction is facilitated by the presence of other fatheads.



2014 ◽  
Vol 71 (5) ◽  
pp. 756-762 ◽  
Author(s):  
Chris K. Elvidge ◽  
Grant E. Brown

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.



Behaviour ◽  
1995 ◽  
Vol 132 (9-10) ◽  
pp. 665-674 ◽  
Author(s):  
R. Jan F. Smith ◽  
Brian D. Wisenden ◽  
Douglas P. Chivers


2019 ◽  
Author(s):  
Adam L Crane ◽  
Maud C O Ferrari ◽  
Ita A E Rivera-Hernández ◽  
Grant E Brown

Abstract Habitat varies in structure, with animals often preferring a certain degree of microhabitat complexity that facilitates fitness-related activities such as predator avoidance. Environments with high predation risk can induce elevated baseline fear and neophobia in prey, but whether microhabitat complexity influences the acquisition of neophobia has yet to be reported. Here, we tested whether exposure to predation risk induces different levels of fear in microhabitats that differed in complexity. We exposed fathead minnows, Pimephales promelas, to predation risk repeatedly (12 times over 4 days) in the form of damage-released chemical alarm cues (compared to water control) in tanks with vertical plant structure distributed either throughout the tank (complex habitat) or clumped together (simple habitat). Then, we tested minnows before and after exposure to a novel odor in tanks with either the same microhabitat complexity (i.e., familiar habitats) or in tanks with novel habitat that had different substrate structure and no vertical structure. Minnows in the complex habitat showed less overall movement one day after the background risk period, whereas individuals in the simple habitat showed reduced movement regardless of prior risk exposure. We observed stronger effects in the novel habitat, where background risk in both simple and complex habitats caused neophobia. However, individuals from the simple background habitat showed higher baseline fear behaviors. Hence, for minnows, low microhabitat complexity appears to lead to elevated fear, which remains even after a habitat change.



2003 ◽  
Vol 81 (10) ◽  
pp. 1671-1677 ◽  
Author(s):  
Jason P Marcus ◽  
Grant E Brown

Recent studies have shown that juvenile centrachids undergo ontogenetic shifts in their behavioural response towards conspecific and heterospecific chemical alarm cues based on threat-sensitive trade-offs between the benefits associated with predator avoidance and foraging. We conducted laboratory studies to test the hypothesis that the relative concentration of conspecific alarm cues provides relevant information, allowing individuals to maximize these trade-offs. Juvenile (<40 mm standard length) and subadult (>95 mm standard length) pumpkinseed sunfish (Lepomis gibbosus) were exposed to conspecific skin extracts at stock (undiluted) concentration or diluted 1:1 (50%), 1:3 (25%), or 1:7 (12.5%) with distilled water. Juvenile sunfish exhibited significant antipredator responses (relative to the distilled water controls) when exposed to conspecific skin extracts at a concentration as low as 25%. Juveniles exposed to 12.5% skin extract were not significantly different from the distilled water controls. Subadult sunfish exhibited significant antipredator responses only to the two highest concentrations. In response to the two lowest concentrations (25% and 12.5%), however, subadult sunfish exhibited significant foraging responses. These data demonstrate that the relative concentration of chemical alarm cues provides reliable information and allows individuals to accurately assess local predation risk and hence maximize potential trade-offs.



Sign in / Sign up

Export Citation Format

Share Document