Habitat“the resources and conditions present in an area that affect occupancy by a

species” (Morrison 2002)

•More than floristic composition•Structure, arrangement, predators, prey, etc.

•Species-specific•Multiple scales must be understood

D.H. Johnson and T. A. O’Neil. 2001. Wildlife-habitat relationships in Oregon and Washington. Oregon State University Press. Corvallis.

D.H. Johnson and T. A. O’Neil. 2001. Wildlife-habitat relationships in Oregon and Washington. Oregon State University Press. Corvallis.

Progress, Problems, Prospects

• GIS and our increasing ability to measure more and more habitat attributes is good, but these are not substitutes for mechanistic understanding about how and why species are related to various components of their habitat.

• Model prediction accuracy may be improved (currently it is poor) with mechanistic understanding.

• Understandings need to cross scales and address biological (what scale do animals act at) and political (what scale to humans act at) scales.

• This is hard enough for a single species. But increasingly we are called on to provide advice for an ecosystem (multiple species).

(Wiens, J.A. 2002. Predicting species occurrences: progress, problems, and prospects. Pp 739-749. In. Scott et al. (eds.) Predicting species occurrences: issues of accuracy and scale. Island Press)

Assignment

• In Class– Poll your group members for knowledge about habitat

requirements of terrestrial vertebrates in Washington (birds, mammals, reptiles, amphibians)

– Describe a species’ habitat according to Johnson and O’Neil’s approach

• Habitat matrix• Structure matrix• Habitat elements matrix• Population status and distribution matrix

– Discuss how the process could be improved

Assignment

• At home (DUE WEDNESDAY IN LAB)• In 1 page, answer the following two questions

– Using Morrison (2002), consider your species’ habitat needs and discuss the habitat variables you would measure, how you would measure them, and at what scale you would do so, in order to quantify its habitat requirements.

– Using Figures 2 and 3 from Johnson and O’Neil (2001) state what sort of model you would use to investigate the influence of timber harvest in Washington on your species.

– After you decide on a type of model (above), do a literature search to find one publication in the primary literature that applies this sort of model to your species (or another species if one is not out there for your species). List the reference and summarize how the model was used in a few sentences.