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Home > WHY monitor? > Measuring long-term population change | ||||||||||||||
Measuring long-term population change | ||||||||||||||
By population change we mean a tracking of changes in the abundance of animals within a defined area. The question being addressed within your monitoring program is: What are the rates and directions of population change? Note: Setting up a program to track changes in populations does not preclude the investigation of other questions of the data later, such as correlating populations changes to events such as weather, habitat changes, or other factors that may be influencing those changes. Monitoring population change can provide you with the following:
Reasons for Tracking Population Changes. The first requirement of stewardship is to know the condition of the resources under your care. Creating a program to track changes in your populations is part of understanding that condition. Once changes are detected you then can begin developing additional research and management actions as required to understand or mend the problem. If you have no information on the status of the populations you are responsible for, then how will you be able to protect them? How to Best Use this Web Site. As you travel through this web site we suggest that, if you are going to be monitoring the population of a set of species, that you download our long-term change monitoring worksheet. That worksheet will help guide your decision-making process and in the end will provide you with a set of statements that you can incorporate into the proposals and justifications that you may need during the creation of your new monitoring program. National/Regional/State Monitoring Programs Versus Monitoring Your own Land. Several regional or national monitoring programs already exist. Programs such as the Breeding Bird Survey, FrogwatchUSA, North American Amphibian Monitoring Program, MAPS, bird atlases, state waterfowl surveys, Bald Eagle Counts, Christmas Bird Counts, deer check stations may be familiar to you. In most cases participation in this programs is a very good thing, something that we promote and that your data makes important contributions toward. However, in almost all cases the information from these national/regional surveys, even if conducted right on your land, is unlikely to be the best way you could create a survey for that group of animals. These large scale surveys are designed to talk about changes over large expanses. Their power comes from pooling data across many sites and little can be said about the populations that occur at an individual collection site. Basic Rule of Thumb: If you are interested in learning about how animal populations are changing on your land you need to design your own survey and not adopt someone else's protocol or become a part of a national program. Next question: What are you going to monitor? |
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