Cohesive social behaviour shortens the stress response: the effects of conspecifics on the stress response in lake sturgeon Acipenser fulvescens

Abstract

An examination was made of whether social interactions can have a beneficial effect through the attenuation of the stress response in a social species. In the first experiment, one larger (mean +/-s.e. 194.0 +/- 12.5 g) and seven smaller (32.0 +/- 2.6 g) juvenile lake sturgeon Acipenser fulvescens were placed in tanks to determine whether a classic dominance effect would be established based on body size (n = 6). Large fish did not establish a territory or aggressively interact with smaller fish, as there were no significant differences in nearest-neighbour distances and an absence of aggressive behaviour (biting, chasing and pushing). In the second experiment, it was hypothesized that the presence of conspecifics would have a beneficial effect through an attenuation of the stress response. Fish in groups or isolation were stressed by a brief aerial exposure (30 s), and blood plasma was measured at regular time intervals (0, 20, 40, 60, 120 and 240 min) following the stressor via an implanted cannula (n = 9-11). The presence of conspecifics did not affect the peak cortisol response, however, the overall cortisol response was shorter in duration compared to fish in isolation. Furthermore, secondary stress variables (plasma ions and glucose) showed differences between fish in groups and isolation. The results of these experiments suggest that social interaction plays an important and beneficial role in regulating the stress response in cohesive social species such as A. fulvescens.

The effect of temperature and substrate on the development of the cortisol stress response in the lake sturgeon, Acipenser fulvescens, Rafinesque (1817)

“…Barton et al (2000) reported stress specific cortisol responses in the pallid sturgeon, Scaphirhynchus albus. Furthermore, time of day in juvenile green sturgeon, A. medirostris, (Lankford et al 2003) and social context in lake sturgeon, A. fulvescens (Allen et al 2009) have been shown to influence the stress induced cortisol response.…”

The impact of catch-and-release on the foraging behaviour of pike (Esox lucius) when released alone or into groups

“…This potential triggering effect should however not be viewed as social facilitation, as can be the case in Eurasian perch (Perca fluviatilis) (Eklöv, 1992;Nilsson et al, 2006), but rather as an effect of caught and released pike acting like surrounding conspecifics, which indirectly facilitated the resumption of foraging behaviour. It has moreover been shown than juvenile lake sturgeon (Acipenser fulvescens) exhibits shortened stress responses in the presence of conspecifics (Allen et al, 2009). More studies are needed to address the mechanism behind the effects of conspecific presence on fish recovery from stress situations.…”

First Insight into Exploration and Cognition in Wild Caught and Domesticated Sea Bass (Dicentrarchus labrax) in a Maze

“…The vigilance decreases when neighbour distance decreases because information about whether other group members have detected a predator is easier to obtain from nearer individuals [52]. More recently, it has also been shown that social interaction plays an important and beneficial role in regulating the stress response in cohesive social species such as sturgeon ( Acipenser fulvescens ) [53]. The fact that wild fish spent more time in the congener zone could reinforce the hypothesis of higher vigilance in wild fish described above leading them to reduce distance from a congener.…”