The effectiveness of wildlife corridors in theory and in practice

Abstract

Wildlife corridors are useful tools to mitigate the often-negative effects of habitat fragmentation. However, the effect of corridor quality on dispersal, and whether corridors can be used to conserve pollination remain largely unexplored. In this thesis, I investigate the effectiveness of wildlife corridors in theory, and test the utility of corridors to conserve pollination in practice, using a combined approach of lab microcosms and field experiments. There are four aims to my research:
First, using 3D printed experimental microcosms containing populations of Collembola, Folsomia candida, I study how corridor quality affects dispersal, and how it interacts with corridor length and width. My results show that corridor quality is an important factor that influences the movement of individuals.
Second, using replicate ‘four patch’ microcosms, I investigate how habitat connectivity interacts with climate change, and how this affects the persistence of metapopulations. I show that whilst drought stresses populations, these results are mitigated by increased habitat connectivity, potentially buffering extinctions caused by climatic extremes.
Third, in a UK fragmented landscape, I investigate the effect of patch area and isolation on the pollination of English Bluebell (Hyacinthoides non-scripta), a species largely pollinated in spring by queen bumblebees. My results show that patch isolation negatively affects the reproductive success of plants, highlighting the importance of connectivity in maintaining pollination services.
Fourth, I aim to investigate whether linear features can function as corridors for pollinators and increase pollination, using a community level approach. I find that artificial linear features increased the pollination of bee-pollinated plants, but had less effect on fly- and moth-pollinated plants. My results highlight the importance of linear features in conserving bee pollination and using a community level approach in conservation.
Overall, this study demonstrates the values of corridors in conservation ecology. From a practical perspective, corridor quality should be considered when evaluating the effectiveness of corridors and using corridors to connect isolated patches is likely to be an effective strategy in conserving the process of pollination.

Date of Award	21 Mar 2023
Original language	English
Awarding Institution	University of Bristol
Supervisor	Jane Memmott (Supervisor) & Chris F Clements (Supervisor)