Patch size influences perceived patch quality for colonising Culex mosquitoes

1. Colonisation is a critical process driving the abundances and diversity of species in spatially discrete communities. Although patch size and patch quality are well known as determinants of post-colonisation species richness and abundance, less is known about how patch size affects colonisation. 2. Patch size and quality may not be independent, so assessment of potential interactions is necessary for understanding patterns of species abundance in natural systems. In freshwater systems, presence and identity of predators is a dominant determinant of patch quality, with larger habitat patches often supporting larger and more diverse predator assemblages. 3. To examine potential interactions, we manipulated patch size and quality (fish presence/absence) using naturally colonised experimental landscapes and assayed oviposition by Culex mosquitoes. 4. Culex restuans selected patches that were smaller, did not contain fish, and had higher temperatures. We demonstrate that patch size, along with patch quality, can generate patterns of abundance at the colonisation stage that are contradictory to traditional patch size-based models of species distributions.