Dr Jessica Lea
Conservation Scholar Alumnus
BSc Zoology (Hons) – University of Manchester, UK, 2013
PhD Environmental Biology – University of Manchester, UK, 2017
The aim of my PhD was to increase our understanding of the factors that contribute to population growth rates; carrying out the research with two equid species. The first was the Cape mountain zebra, a subspecies that is endemic to the Cape of South Africa and listed as Vulnerable on the IUCN Red List. It exists as a meta-population with over 75 sub-populations overseen by different organisations and landowners, creating a number of population management challenges. In addition, it lives in a diverse environment where the habitat and climate can vary quite dramatically between populations.
We investigated how the environment and the demography of each population can affect growth rates and female fecundity, using both physiological and behavioural measures. We developed a broad-scale assessment of habitat quality for 21 Cape mountain zebra populations and compared this with measures of population performance. In addition, we collected faecal samples from over 160 individuals across seven populations to measure glucocorticoid and androgen metabolite levels. Finally, we surveyed the demography and association patterns of 10 Cape mountain zebra populations and compared population structuring using social network analysis. Our approach was broad and diverse and has allowed us to identify separate potential causes of poor population performance of this species in the field.
My second study species was the Carneddau mountain pony, found in Snowdonia National Park in Wales. The study population consists of over 300 free-living individuals that undergo annual management practices during which stallions are sometimes moved from the population. We aimed to assess the physiological and behavioural response of individuals to this change by measuring faecal glucocorticoids and looking at changes to social networks. Ideally these findings will increase our understanding of the impact moving individuals from a population has, which is particularly important as translocation events often take place as part of conservation management plans.
More generally, I am interested in using broad-scale measurements from different disciplines to understand the drivers of population performance, for population monitoring purposes and as an evaluation method for species population management plans.
Lea, JMD, Kerley, GIH, Hrabar, H, Barry, T & Shultz, S (2016) Recognition and management of ecological refugees: a case study of the Cape mountain zebra. Biological Conservation, 203: 207-215.
Lea, JMD, Keen, AN, Nudds, RL & Shiels, HA (2015) Kinematics and energetics of swimming performance during acute warming in brown trout Salmo trutta. Journal of Fish Biology, 88, 403-417.
Lea, JMD, Walker, SL, Matevich, SC, Kerley, GIH, Jackson, J & Shultz, S (in review) Macrophysiology uncovers relationships between demography, habitat and population performance in a vulnerable species, the Cape mountain zebra.
Jackson, J, Lea, JMD, Alberts, N, Matevich, SC, Rubenstein, DI, Kerley, GIH & Shultz, S (in review) A macroecological evaluation of social network structure variation in the Cape mountain zebra.