Heather Coreen Proctor

Mites and birds: diversity, parasitism and coevolution

Ectoparasites play important roles in the lives of birds. Among these parasites, mites offer unique potential because of their extraordinary ecological and evolutionary diversity. However, the basic biology of most mites is poorly understood, and misleading extrapolations are sometimes made from better studied systems involving lice and fleas. Most importantly, not all bird-associated mites are parasitic; indeed, recent research suggests that some might even be beneficial. Here, we summarize what is known about the diversity of bird-mite relationships, and highlight how mites provide an ideal tool for the study of host life histories, sexual selection, immunocompetence and cospeciation.

Extracting aquatic mites from stream substrates: a comparison of three methods

Aquatic mites (Hydrachnida, Oribatida, Halacaroidea) are diverse, and can reach high densities in the substrates of streams and rivers. Although they are a ubiquitous component of these habitats, their small size means that they are often overlooked. Using substrate samples from streams in tropical Queensland, I compared the thoroughness and time-based efficiency of three methods of extraction: sorting live samples without magnification (live-picking); exhaustive sorting of preserved samples using a dissecting microscope (microscope-picking); and kerosene-flotation of preserved samples followed by sorting with a dissecting microscope (kero-float). Live-picked samples yielded significantly fewer individuals and species than other methods, and were biased towards larger species. Oribatids and halacarids were not found when live-picking was used. Live-picking and kero-float methods provided similar numbers of mites per minute of sampling effort, whereas microscope-picking had a lower efficiency than kero-float. A combination of live-picking and kerosene-floatation is recommended for thorough surveys of stream acarofauna.