To Feed or Not to Feed? Coral Reef Fish Responses to Artificial Feeding and Stakeholder Perceptions in the Aitutaki Lagoon, Cook Islands

Abstract

Feeding wild animals is a regular habit in ecotourism worldwide with poorly known consequences for ecosystem functioning. This study investigates how effective bread feeding is at attracting coral reef fish in the South Pacific, which feeding groups of fish are most attracted, and how natural foraging rates of an omnivorous and a grazingdetritivorous fish are affected. Data were collected at sites where fish are regularly fed bread by snorkellers and at comparison sites where bread was only provided for this study, within the Aitutaki lagoon (Cook Islands). The fish community was censused and foraging rates of two model species (Chaetodon auriga, Ctenochaetus striatus) were quantified one hour before, during, and an hour after feeding events. Twentyfive percent of the species present at all sites (piscivores-invertivores) were effectively attracted to bread. Overall, mean fish density was higher at tourism feeding sites than at the comparison sites. During bread feeding events, taxonomic richness decreased, compared to the hours prior and after feeding across all sites. As piscivore-invertivores were consistently attracted to bread, localized shifts in their dominance over other trophic groups may be expected if bread feeding persists, likely carrying consequences for ecosystem functioning. The effect of bread feeding events on natural foraging rates differed between the model species. C. auriga ceased foraging on natural foods to feed on bread. Although C. striatus never fed on bread, its foraging rate on epilithic algal matrices decreased during bread feeding events. This indirect non-lethal ecological consequence of bread feeding contributes a previously unanticipated example relevant to the "ecology of fear" in marine fish. Stakeholder interviews revealed that locals favor feeding to sustain tourist satisfaction, whereas tourists appreciate snorkeling regardless of feeding. This indicates an opportunity for restrictions on fish feeding with minimal drawbacks for tourism. Future research on fish metabolism and cascading effects on the reef benthos may reveal further impacts of feeding on coral reef communities.

The influence of tourism-based provisioning on fish behavior and benthic composition

“…However, higher species numbers were also found in fish provisioned sites, which is inconsistent with previous studies (Milazzo et al 2005;Ilarri et al 2008). Prinz (2017) suggested that tourismbased provisioning will only attract certain species and that such activities will deter others, thus reducing species richness, although this pattern was not consistently observed across all four of the survey sites within this study. Green Island had more fish species, and showed significantly different fish composition due to fish provisioning.…”

“…The changes in the assemblage structure of coral reef fish communities that were observed in this study due to tourism-based provisioning align with previous works (Milazzo et al 2005;Albuquerque et al 2014;Prinz 2017). The number of recorded fish species at the provisioned sites of this study (56,72 in Kenting and Green Island) were also fewer than at other sites in the same location from a previous survey (65,90;Heatwole et al in prep).…”

Does artificial feeding affect large carnivore behaviours? The case study of brown bears in a hunted and tourist exploited subpopulation

“…For example, supplementary feeding has been considered necessary because: (a) the distribution and availability of natural food might limit threatened populations (Ewen et al, 2014;Thierry et al, 2020); (b) there is a hypothesised benefit to providing safe food sources, free of veterinary drugs or poisons (Oro et al, 2013); (c) it might aid recovery of hunted populations (Delibes-Mateos et al, 2009) or (d) it may prevent damages in forestry and agriculture (Arnold et al, 2018;Borowski et al, 2019;Selva et al, 2014). But artificial feeding is also widely used to support human leisure activities, by both the hunting and ecotourism industries (Orams, 2002;Penteriani et al, 2017;Prinz et al, 2020;Steyaert et al, 2014), e.g. : (a) to maintain a high quality of trophy animals and a high density of animals for hunting, as well as to attract them to shooting spots (Selva et al, 2014); and (b) to increase the likelihood of wildlife observations as a touristic attraction (Orams, 2002;Penteriani et al, 2017;Prinz et al, 2020;Selva et al, 2014).…”

“…But artificial feeding is also widely used to support human leisure activities, by both the hunting and ecotourism industries (Orams, 2002;Penteriani et al, 2017;Prinz et al, 2020;Steyaert et al, 2014), e.g. : (a) to maintain a high quality of trophy animals and a high density of animals for hunting, as well as to attract them to shooting spots (Selva et al, 2014); and (b) to increase the likelihood of wildlife observations as a touristic attraction (Orams, 2002;Penteriani et al, 2017;Prinz et al, 2020;Selva et al, 2014).…”