Estimating observer error and steelhead redd abundance using a modified Gaussian area-under-the-curve framework

Murdoch, Andrew R.; Herring, Chad J.; Frady, Charles H.; See, Kevin; Jordan, Chris E.

doi:10.1139/cjfas-2017-0335

Advanced Search

Select up to three search categories and corresponding keywords using the fields to the right. Refer to the Help section for more detailed instructions.

Search our Collections & Repository

Advanced Search
Custom Query

All these words:

For very narrow results

This exact word or phrase:

When looking for a specific result

Any of these words:

Best used for discovery & interchangable words

None of these words:

Recommended to be used in conjunction with other fields

Language:

Dates

Publication Date Range:

to

Document Data

Title:

Document Type:

Library

Collection:

Series:

People

Author:

Clear All

Query Builder

Query box

Clear All

For additional assistance using the Custom Query please check out our Help Page

The NOAA IR serves as an archival repository of NOAA-published products including scientific findings, journal articles, guidelines, recommendations, or other information authored or co-authored by NOAA or funded partners. As a repository, the NOAA IR retains documents in their original published format to ensure public access to scientific information.

i

Estimating observer error and steelhead redd abundance using a modified Gaussian area-under-the-curve framework

2018
By Murdoch, Andrew R. ; Herring, Chad J. ; Frady, Charles H. ; ...
Source: Canadian Journal of Fisheries and Aquatic Sciences, 75(12), 2149-2158

[PDF-752.41 KB]

Details You May Also Like

Details:

Journal Title:

Canadian Journal of Fisheries and Aquatic Sciences
Personal Author:

Murdoch, Andrew R. ; Herring, Chad J. ; Frady, Charles H. ; See, Kevin ; Jordan, Chris E.

Murdoch, Andrew R. ; Herring, Chad J. ; Frady, Charles H. ; See, Kevin ; Jordan, Chris E. Less -
NOAA Program & Office:

NMFS (National Marine Fisheries Service) ; NWFSC (Northwest Fisheries Science Center)

NMFS (National Marine Fisheries Service) ; NWFSC (Northwest Fisheries Science Center) Less -
Description:

This study examined how a suite of habitat and environmental variables relate to the ability of a stream surveyor to identify (observer efficiency) and distinguish (observer accuracy) steelhead (Oncorhynchus mykiss) redds from other stream features. Two existing spawning survey protocols that included one or two redd observers were used to develop models to estimate redd observer error. In most cases, steelhead redd abundances using raw redd counts were underestimated. Mean annual rates of observer efficiency ranged from 0.44 to 0.57, and observer accuracy ranged from 0.67 to 0.83. Regardless of the observer error model used, adjusted annual redd abundance estimates were generally unbiased (range 1.6–0.6 redds). A Gaussian area-under-the-curve methodology that incorporates redd count data and observer error rates was used to generate unbiased estimates of steelhead redd abundance in the Wenatchee (170 redds, coefficient of variation (CV) = 44%) and Methow (106 redds, CV = 41%) rivers. Unbiased estimates of redd abundance will help inform new population viability analyses to better prioritize those populations with the greatest conservation need.
Source:

Canadian Journal of Fisheries and Aquatic Sciences, 75(12), 2149-2158
DOI:

https://doi.org/10.1139/cjfas-2017-0335
ISSN:

0706-652X;1205-7533;
Format:

pdf
Publisher:

Canadian Science Publishing
Document Type:

Journal Article
Rights Information:

Other
Compliance:

Library
Main Document Checksum:

[+]

urn:sha-512:705695de698e5388dacc267d5250f870ca77023535f3bd9094348ca57b02e4d22a9a6bcfd4e3b5ef8ba39b32aeb43c9110ff7b689128527127a484f446ce46ca
Download URL:

https://repository.library.noaa.gov/view/noaa/69183/noaa_69183_DS1.pdf
File Type:

No Additional Files

More +

Estimating observer error and steelhead redd abundance using a modified Gaussian area-under-the-curve framework

Details:

Supporting Files

You May Also Like