EPA Science Inventory

Mapping sources, sinks, and connectivity using a simulation model of northern spotted owls- 5/20/2014

Citation:

Schumaker, N., J. Dunk, J. Heinrichs, J. Lawler, AND A. Brookes. Mapping sources, sinks, and connectivity using a simulation model of northern spotted owls- 5/20/2014. Presented at International Association for Landscape Ecology, 2014 Annual Symposium, Anchorage, AK, May 18 - 22, 2014.

Description:

Source-sink dynamics are an emergent property of complex species- landscape interactions. A better understanding of how human activities affect source-sink dynamics has the potential to inform and improve the management of species of conservation concern. Here we use a study of the northern spotted owl (Strix occidentalis caurina) to introduce new methods for quantifying source-sink dynamics that simultaneously describe the population-wide consequences of changes to landscape connectivity. Our spotted owl model is mechanistic, spatially- explicit, individual-based, and incorporates competition with barred owls (Strix varia). Our observations of spotted owl source-sink dynamics could not have been inferred solely from habitat quality, and were sensitive to landscape connectivity and the spatial sampling schemes employed by the model. We conclude that a clear understanding of source-sink dynamics can best be obtained from sampling simultaneously at multiple spatial scales. Our methodology is general, can be readily adapted to other systems, and will work with population models ranging from simple and low-parameter to complex and data-intensive.

Purpose/Objective:

Wildlife are a concern to The Environmental Protection Agency for many reasons. Wildlife are indicators of ecosystem health, they respond to compounds and activities that are regulated by the Agency, they represent ecosystem services, and more. Population viability analysis (PVA) models are widely used to forecast trends in wildlife population size and distributions through time. This short presentation will discuss efforts being made to improve PVA models through the addition of additional biological realism, and through enhancements that add relevance to managers and regulators. This spoken presentation will use the northern spotted owl as a case study to illustrate the new research advancements. The spotted owl is a species of conservation concern that is heavily impacted by human activities.

URLs/Downloads:

ABSTRACT - SCHUMAKER.PDF   (PDF,NA pp, 35.273 KB,  about PDF)

Record Details:

Record Type: DOCUMENT (PRESENTATION/ABSTRACT)
Completion Date: 05/27/2014
Record Last Revised: 05/27/2014
Record Created: 05/27/2014
Record Released: 05/27/2014
OMB Category: Other
Record ID: 276894

Organization:

U.S. ENVIRONMENTAL PROTECTION AGENCY

OFFICE OF RESEARCH AND DEVELOPMENT

NATIONAL HEALTH AND ENVIRONMENTAL EFFECTS RESEARCH LAB

WESTERN ECOLOGY DIVISION

ECOLOGICAL EFFECTS BRANCH