| dc.description.abstract | Although herring gulls are well known for urban-living, their behaviour within urban environments has not been as well researched as their behaviour in more rural areas. In this thesis, I investigate whether wild herring gulls show differing levels of object neophilia in experimental presentations of a common and novel anthropogenic object across urban-rural gradient (Chapter 2). I did not find clear evidence of object neophilia as the environmental context was influential, in which increasing human presence increased vigilance and non-participation. I considered whether early-life experience could influence later-life behaviour and urban use in the formation of dietary preferences in captive-reared herring gull chicks (Chapter 3). I demonstrate that despite contrary experimental diets of terrestrial and marine-sourced foods, herring gull chicks predominantly prefer fish. Next, I investigated individual variations in urban-facilitating behaviours within and among captive reared chicks over their development (Chapter 4). I tested whether behavioural responses to novel objects and people were consistent over time and found that individuals were still flexible in their behavioural responses, with only aggression towards human handlers considered a consistent behavioural trait. In Chapter 5, I GPS-tracked captive-reared and wild juvenile herring gulls' movement and behaviour as a first for the UK. I tested whether differences in early-life experience would affect the dispersal and ecology of juveniles’ behaviour, particularly with regard to the use of (sub)urban areas. I demonstrate that GPS-tracking of juvenile herring gulls is possible with no apparent effect on survival or sighting likelihood. Over the 12-month study period, we found that rescued and wild juveniles do show differences in their behavioural ecology, although all juveniles visited and avoided the same habitats. Rescue juveniles showed larger home ranges and a preference for more rural habitat use than wild juveniles, but they did show more active classified behaviours within urban areas than wild juveniles. Interestingly, all juveniles did not venture far out to sea and would remain coastal or inland, with rescued juveniles showing less use of inland saltwater areas. These juveniles’ behaviour contrasts with previous studies of adult herring gulls. Collectively, my findings highlight the importance of increasing our understanding of individual behavioural responses, and the need to research the impact of escalating anthropogenic change within all animal life history stages in order to conserve biodiversity and continue our coexistence. | en_GB |
