Adjusting foraging strategies: a comparison of rural and urban common mynas (Acridotheres tristis)
Establishment in urbanized environments is associated with changes in physiology, behaviour, and problem-solving. We compared the speed of learning in urban and rural female common mynas, Acridotheres tristis, using a standard visual discrimination task followed by a reversal learning phase. We also examined how quickly each bird progressed through different stages of learning, including sampling and acquisition within both initial and reversal learning, and persistence following reversal. Based on their reliance on very different food resources, we expected urban mynas to learn and reversal learn more quickly but to sample new contingencies for proportionately longer before learning them. When quantified from first presentation to criterion achievement, urban mynas took more 20-trial blocks to learn the initial discrimination, as well as the reversed contingency, than rural mynas. More detailed analyses at the level of stage revealed that this was because urban mynas explored the novel cue-outcome contingencies for longer, and despite transitioning faster through subsequent acquisition, remained overall slower than rural females. Our findings draw attention to fine adjustments in learning strategies in response to urbanization and caution against interpreting the speed to learn a task as a reflection of cognitive ability.
KeywordsBehavioural flexibility Reversal learning Discrimination learning Urbanisation Rural birds Indian myna
The research was funded by a FP7-PEOPLE-2013-IRSES research staff exchange grant to TB, SH, OG and ASG. OG was additionally supported by Gu227/16-1 and IF by an FWF grant (Y366-B17) to TB. We thank Nicole Ward and Mattsen Yeark for assisting with data collection and staff at the University of Newcastle Central Animal House for caring for the birds.
- Christidis L, Boles W (2008) Systematics and taxonomy of Australian birds. CSIRO Publishing, MelbourneGoogle Scholar
- Crisp H, Lill A (2006) City slickers: habitat use and foraging in urban common mynas Acridotheres tristis. Corella 30:9–15Google Scholar
- Dhami MK, Nagle B (2009) Review of the biology and ecology of the Common Myna (Acridotheres tristis) and some implications for management of this invasive species. Report. Pacific Invasives Initiatives, AucklandGoogle Scholar
- Feare CJ (2010) The use of Starlicide® in preliminary trials to control invasive common myna Acridotheres tristis populations on St Helena and Ascension islands, Atlantic Ocean. Conserv Evid 7:52–61Google Scholar
- Pearce JM (1997) Animal learning and cognition: an introduction. Psychology Press, HoveGoogle Scholar
- Reilly JS (2001) Euthanasia of animals used for scientific purposes. Australian and New Zealand Council for the Care of Animals in Research and Teaching (ANZCCART) Publications, AdelaideGoogle Scholar
- Sengupta S (1976) Food and feeding ecology of the common myna Acridotheres tristis. Proc Indian Natl Sci Acad 42:338–345Google Scholar
- Tidemann CR (2006) Common Indian myna Website. http://fennerschoolassociated.anu.edu.au/myna/trapping.html. Accessed 18 Oct 2016