USGS ScienceSearch

USGS · 5224479

SAS procedures for designing and analyzing sample surveys

Abstract

Complex surveys often are necessary to estimate occurrence (or distribution), density, and abundance of plants and animals for purposes of re-search and conservation. Most scientists are familiar with simple random sampling, where sample units are selected from a population of interest (sampling frame) with equal probability. However, the goal of ecological surveys often is to make inferences about populations over large or complex spatial areas where organisms are not homogeneously distributed or sampling frames are in-convenient or impossible to construct. Candidate sampling strategies for such complex surveys include stratified,multistage, and adaptive sampling (Thompson 1992, Buckland 1994).

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Joshua D. Stafford, Kenneth J. Reinecke, Richard M. Kaminski. 2003. SAS procedures for designing and analyzing sample surveys. https://doi.org/10.1890/0012-9623(2003)84%5B111%3Aspfdaa%5D2.0.co%3B2

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related USGS reports

Suppression of invasive Brown Treesnakes and reintroduction of native avifauna on Guam

Many agencies and interest groups are committed to re-establishing components of Guam's native avifauna through the reintroduction of captive-reared birds or translocation from other islands in the Marianas if the Brown Treesnake ( Boiga irregularis ; BTS) can be eliminated. Island-wide eradication of BTS from Guam continues to appear out of reach, but with recent and future advancement in BTS suppression technology, we may soon reach a point where suppression may enable the reintroduction of some of Guam's extirpated bird species. Our simulations indicate that bird persistence in Guam's forests would only be possible at a suppression level just short of full eradication.

Bulletin of the Ecological Society of America

Quantifying drought’s influence on moist soil seed vegetation in California’s Central Valley through remote sensing

Across the Central Valley of California, millions of wintering waterfowl rely on moist soil seed (MSS) plants that grow in managed seasonal wetlands as a critical source of food. Estimates of MSS plant production are used to set waterfowl habitat targets yet this information is not well known. We created the first Central Valley-wide time series maps of MSS plant distributions and productivity. We found that MSS plant seed yield declined in critical drought years, which corresponded with reduced water delivery to managed wetlands. Our results provide improved food resource estimates and information to help managers prioritize actions as water supply becomes more uncertain with climate change.

California

Best practices for virtual participation in meetings: Experiences from synthesis centers

The earth environment is a complex system, in which collaborative scientific approaches can provide major benefits by bringing together diverse perspectives, methods, and data, to achieve robust, synthetic understanding (Fig. 1). Face-to-face scientific meetings remain extremely valuable because of the opportunity to build deep mutual trust and understanding, and develop new collaborations and sometimes even lifelong friendships (Alberts 2013, Cooke and Hilton 2015). However, it has been argued that ecologists should be particularly sensitive to the environmental footprint of travel (Fox et al. 2009); such concerns, along with the time demands for travel, particularly for multi-national working groups, provide strong motivation for exploring virtual attendance. While not replacing the richness of face-to-face interactions entirely, it is now feasible to virtually participate in meetings through services that allow video, audio, and file sharing, as well as other Web-enabled communication.

Bulletin of the Ecological Society of America