| Dr
Nicholas Macgregor |
 |
| Current work at Natural England | |
| I
am an ecologist working on the development of conservation strategies,
with a particular focus on adaptation to climate change and on large-scale
conservation management. My current research interests include: • Climate change refugia • Design and implementation of ecological networks • Different approaches to large-scale conservation and ecological restoration • Understanding what adaptation to climate change in nature conservation will involve in practice, and translating adaptation principles into recommendations for conservation practitioners • Vulnerability of different species and ecosystems to climate change I am also chair of the cross-European ENCA Climate Change Group, which aims to share information among European nature conservation agencies and to facilitate the translation of climate change evidence into effective conservation management |
|
| PhD Research | |
| Despite
much study of bird plumage colours, it is not clear why there is such
diversity among bird species in the extent and pattern of sexual dichromatism
and why dichromatic colours vary across species. I studied one particularly
widespread colour scheme of dichromatism in passerine birds: black
plumage in males and another colour, often brown or a similarly ‘dull’
colour, in females. I investigated a number of hypotheses relating
to black plumage in males being a signal. Using a mixture of comparative
analysis, experiments and observations in the field, I attempted to
answer the following questions: Where on the body does sexually dichromatic
black plumage most commonly occur? Is black plumage more conspicuous
than brown plumage (the common female colour in these sexually dichromatic
species) and is its conspicuousness influenced by microhabitat? Across
species, is sexual dichromatism involving black male plumage associated
with increased levels of competition between males and/or with particular
types of habitat and light environment? Are differences in patterns
of black plumage among males of related species consistent with the
hypothesis that sexually dichromatic black plumage is a signal of
species identity? I found that sexually dichromatic black occurs most commonly on the head. Black appears to be more conspicuous, at least to predators and probably also to birds of the same species, than brown, and more conspicuous in microhabitats that have less foliage canopy overhead than in those under a denser canopy. There was no association between sexually dichromatic black plumage and the level of sexual size dimorphism (used as an indirect measure of the intensity of competition between males). I found an association between black plumage in males and relatively open habitat, though only in the ‘Passerida and allies’ group of passerines. However, a field study of 14 species of wood warblers (Parulini) found the opposite trend – males of species with larger amounts of black plumage sang from positions under denser canopy. I found a negative association between black dichromatism and male body size in some groups of passerines. Comparisons of congeneric species produced no evidence that patterns of sexually dichromatic black plumage have evolved to facilitate species recognition. I try to continue this research in my spare time, when time permits. |
|
| Nick Macgregor |
| Current work at Natural England |
| PhD Research |
Department of Zoology, University of Cambridge, Downing Street, Cambridge
CB2 3EJ, U. K.