Response to conspecific and heterospecific alarm cues by pumpkinseeds in simple and complex habitats: field verification of an ontogenetic shift

Abstract

Three focal size classes [small (<40 mm, standard length, L S ), medium (40-80 mm L S ) and large (>80 mm L S )] of pumpkinseed Lepomis gibbosus were exposed to conspecific or one of three heterospecific chemical alarm cues under one of three levels of habitat complexity (low, intermediate and high). Under low and intermediate habitat complexities, pumpkinseeds <80 mm L S exhibited a significant antipredator response when exposed to the chemical alarm cues of heterospecific prey guild members (largemouth bass Micropterus salmonides and hypoxanthine-3-N-oxide, the putative Ostariophysan alarm 'pheromone'), while pumpkinseeds >80 mm L S exhibited a foraging response. Under highly complex habitats, pumpkinseeds of all three size classes exhibited an antipredator response. Moreover, under all three habitat conditions, pumpkinseeds of all size classes exhibited an antipredator response to conspecific alarm cues. There was no change in behaviour under any treatment combination in response to an allopatric heterospecific control (swordtails Xiphophorus helleri). These results provide the first field verification of the size dependent use of chemical alarm cues by centrarchids and demonstrate that microhabitat complexity significantly influences the threat-sensitive use of these cues. # 2005 The Fisheries Society of the British Isles

To fear or to feed: the effects of turbidity on perception of risk by a marine fish

“…These results indicate that in situations where visual signals are compromised, prey will increase their response to chemical information, as has been found in mate-selection scenarios [11]. The significant effects of turbidity on the antipredator behaviour of a marine fish, identified here, support previous studies on freshwater fish at similar turbidities [3], and when visual information was reduced via habitat complexity [15] rather than turbidity.…”

“…increased antipredator behaviours [15]. As per the 'sensory compensation' hypothesis, A. polyacanthus increased its reliance on chemical input to assess its risk of predation in situations where visual information was limited.…”

Turbidity amplifies the non‐lethal effects of predation and affects the foraging success of characid fish shoals

“…This hypothesis assumes that reduced anti-predator behaviour and visual risk perception should result in higher or similar ingestion of invertebrates in turbid compared to clear waters. Conversely, our results indicated that fish shoals exhibited stronger predator avoidance behaviour in turbid than in clear water (Golub, Vermette & Brown, 2005;Swanbrow Becker & Gabor, 2012). We suggest that turbidity-induced visual obstruction amplifies the negative effects of predator presence on intermediate consumer fish feeding behaviour, ultimately resulting in higher prey survival.…”

Visual and Chemical Prey Cues as Complementary Predator Attractants in a Tropical Stream Fish Assemblage

“…Many groups of freshwater fishes produce chemical cues in the epidermis which are released into the water following mechanical damage, as would occur during a predation event [8]. Upon detection by conspecific receivers, these cues have been shown to elicit a suite of antipredator or alarm responses [9] in centrarchid [10], salmonid [11], cyprinid [12], cyprinodontiform [2], esocid [13], and poeciliid [14] species. Due to their manner of release, these chemical cues cannot be manipulated by a predator and likely serve as reliable indicators of increased risk to receivers subject to similar predation pressures [15], which is not always the case with potentially misleading visual cues [3].…”