9458

• UCREFRP Catalog Number: 9458
• Author: National Park Service.
• Title: Workshop on Population Estimates for Colorado Pikeminnow and Humpback Chub.
• USFW Year: 2001.
• USFW - Doc Type: Fort Collins.
• Copyright Material: NO

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Petersen Population Estimate

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Assumptions of the model

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These assumptions must be met to obtain valid estimates using the
Petersen population estimate:

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1)

Marked fish do not lose their marks prior to the recapture period.

2)

Marked fish are not overlooked in the recapture sample.

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3)

Marked and unmarked fish are equally vulnerable to capture in the
recapture period.

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4 )

Marked and unmarked fish have equal mortality rates during the interval
between the marking and recapture sample periods.

5)

Following release, marked animals become randomly mixed with the
unmarked ones, or recapture effort is distributed in proportion to the
number of animals in different parts of the population area.

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6) There are no additions to the population during the study interval.

Literature Cited

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Van Den Avyle, M. J. 1993. Dynamics of exploited fish populations. Pages
105-135 in C. C. Kohler and W. A. Hubert, editors. Inland fisheries
management in North America. American Fisheries Society, Bethesda,
Maryland.

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