Risk perception of nesting Great Blue Herons: experimental evidence of habituation

Abstract

The nesting behaviour of the Great Blue Heron ( Ardea herodias L., 1758) was studied in western Canada in 1998 and 1999 to (i) investigate how individual parents assess risk when repeatedly exposed to a disturbance stimulus (an investigator) and (ii) experimentally test in the field whether any variation in their nest defense behaviour was due to experience with the disturbance stimuli or the stage of the nesting period. Heron response declined through the nesting period and the level of response varied among colonies, suggesting different perceptions of risk among groups of herons in the study. It was experimentally shown that variation in the response of herons through one nesting period was due to both behavioural habituation and the stage of the nesting period. Response was stronger in 1999 than in 1998, indicating that habituation did not hold between nesting periods. In general, habituation in herons may bode well for their potential to persist in areas with light human use. But irrespective of habituation, stimuli early in the nesting period and large or novel events may still cause herons to abandon their nests owing to the effects of the stage of the nesting period.

Can Convict Cichlids (Amatitlania siquia) Socially Learn the Degree of Predation Risk Associated with Novel Visual Cues in Their Environment?

“…The taxonomically widespread occurrence of neophobia and habituation (e.g. [4,11,14,15,27,49]) suggests that, like harbour seals, many animals will initially express antipredator behaviour (to varying degrees) toward a wide range of novel cues encountered in their environment and allow individual experience to slowly dictate which cues are safe. We suggest that a thorough understanding of predation risk assessment requires an understanding of how animals learn about both threatening and non-threatening cues, and how these two forms of learning might interact.…”

“…In contrast, examples of animals learning to recognize non-threatening cues (the latter approach) involve only asocial information (i.e. habituation [11,14,15]).…”

Avian Resources of the Northern Gulf of Mexico

“…In many cases, however, birds habituate to the presence of humans, and sometimes become more aggressive (Safina and Burger 1983;Vennesland 2010), as they do at landfills (Pons and Migot 1995). Closing landfills, however, can decrease reproductive success and survival of young birds that have difficulty foraging in other situations (Pons and Migot 1995).…”

“…Habitat loss amplifies the effects of human disturbance (Burger 1981d;Skagen et al 2001). Reducing the effects of human disturbance can involve reducing the amount and types of human activities, prohibiting the presence of dogs or off-road vehicles, or habituating birds to the presence of people (Vennesland 2010).…”

Socially learned recognition of predation risk and non-risk : a theoretical model and empirical test of learning ability in the convict cichlid (amatitlania siquia)

“…Suboski et al 1990, Ferrari andChivers 2009) or a decrease (e.g. Deecke et al 2002, Vennesland 2010 in the expression of antipredator behaviour toward a cue over time. For convenience, throughout this thesis I will occasionally use the term 'fear' to indicate the expression of antipredator behaviour by an individual toward a given cue.…”