CSIRO Publishing blank image blank image blank image blank imageBooksblank image blank image blank image blank imageJournalsblank image blank image blank image blank imageAbout Usblank image blank image blank image blank imageShopping Cartblank image blank image blank image You are here: Journals > Wildlife Research   
Wildlife Research
Journal Banner
  Ecology, Management and Conservation in Natural and Modified Habitats
blank image Search
blank image blank image
blank image
  Advanced Search

Journal Home
About the Journal
Editorial Structure
Online Early
Current Issue
Just Accepted
All Issues
Special Issues
Sample Issue
For Authors
General Information
Submit Article
Author Instructions
Open Access
For Referees
Referee Guidelines
Review an Article
Annual Referee Index
For Subscribers
Subscription Prices
Customer Service
Print Publication Dates

blue arrow e-Alerts
blank image
Subscribe to our Email Alert or RSS feeds for the latest journal papers.

red arrow Connect with us
blank image
facebook twitter LinkedIn


Article << Previous     |     Next >>   Contents Vol 32(3)

Indexing principles and a widely applicable paradigm for indexing animal populations

Richard M. Engeman

National Wildlife Research Center, 4101 LaPorte Avenue, Fort Collins, CO 80521-2154, USA. Email: richard.m.engeman@aphis.usda.gov
PDF (110 KB) $25
 Export Citation


Monitoring animal populations is an essential component of wildlife research and management. Population indices can be efficient methods for monitoring populations when more labour-intensive density-estimation procedures are impractical or invalid to apply, and many monitoring objectives can be couched in an indexing framework. Indexing procedures obtain maximal utility if they exhibit key characteristics, including being practical to apply, being sensitive to changes or differences in the target species’ population, having an inherent variance formula and allowing for precision in index values, and relying on as few assumptions as possible. Additional useful characteristics include being able simultaneously to monitor multiple animal species and to describe spatial characteristics of the species monitored. Here, a paradigm is presented that promotes the characteristics that make indices most useful. Observations are made at stations located throughout the area of interest. Stations can take many forms, depending on the observations, and range from points for visual counts to tracking plots to chew cards, and many others. A wide variety of observation methods for many animal species can fit into this format. Observations are made at each station on multiple occasions for each indexing session. Geographic location data for each station are encouraged to be collected. No assumptions of independence are made among stations, nor among observation occasions. Measurements made at each station are required to be continuous or unboundedly discrete. The formula for a general index to describe population levels is presented and its variance formula is derived. Issues relevant to the application of this methodology, and indices in general, are discussed.

Subscriber Login

Legal & Privacy | Contact Us | Help


© CSIRO 1996-2015