Conclusion:
There remains a pressing concern of global declining butterfly
populations, mainly due to anthropogenic pressure from urban development
(Van Swaay and Warren., 1999). Green spaces within urban locations may
help to maintain total abundance and species diversity (Hennig and
Ghazoul, 2011), but habitat fragmentation and smaller size and quality
of habitat patches will alter community composition (Belinsky et al.,
2019). The structural similarities between urban and rural habitats and
the limited extent of urbanisation on Lipsi Island may have driven the
overlap in abundance and diversity of butterflies and vegetation, whilst
the greater habitat heterogeneity and discarded food in urban
environments could have promoted the abundance and species richness of
generalist and opportunistic birds. Thus, metrics other than simple
counts of individuals and species are needed to characterise the impacts
of urbanisation on community composition across multiple trophic levels.
Future research should aim to characterise changes in community
structure along a gradient of urban development and island size and the
implications for ecosystem functioning. Whilst butterflies were
considered as important indicator species here, follow-up studies should
quantify effects of urbanisation on other pollinators and arthropod
assemblages for a more complete understanding of changes throughout the
food web. Finally, dietary characterisation is required to quantify
changes in the strength and diversity of ecological interactions, which
could help elucidate impacts of urbanisation on the flow of energy
through ecological networks.