Planning programs to estimate salmon harvest with coded-wire tags

1998 ◽  
Vol 55 (8) ◽  
pp. 1983-1995 ◽  
Author(s):  
David R Bernard ◽  
Robert P Marshall ◽  
John E Clark

Methods are presented for planning individual catch-sampling, tagging, and field-sampling programs to estimate salmon (Oncorhynchus spp.) harvest in recreational and commercial fisheries from several hatchery-produced and wild cohorts through recovery of coded-wire tags. We show how to determine sample sizes sufficiently large to detect harvest and link sample sizes to expenditures through linear and allometric cost functions to determine optimal tagging and catch-sampling rates. Sample sizes that will minimize bias and variance are charted for field-sampling programs designed to estimate the fraction of a cohort with tags. We describe sampling strategies that can be used to detect or to minimize bias in harvest estimates from tag loss, tag-induced mortality, tag-induced straying, and nonrandom sampling. Methods are demonstrated with data on cohorts of chinook (O. tshawytscha) and coho salmon (O. kisutch) from Alaska.


2021 ◽  
pp. 1-11
Author(s):  
Jeffrey G. Fidgen ◽  
Mark C. Whitmore ◽  
Chris J.K. MacQuarrie ◽  
Jean J. Turgeon

Abstract Adelges tsugae Annand (Hemiptera: Adelgidae), a nonindigenous insect pest of hemlock (Tsuga spp.) (Pinaceae) in eastern North America, spends most of its life cycle within an ovisac, which resembles a woolly white mass on twigs. We evaluated the probability of detecting adelgid wool with Velcro®-covered balls when taking an increasing number of samples per tree (field sampling) and number of trees per simulated stand. We examined the relationship between the detection of adelgid wool using this technique and the incidence of A. tsugae-infested twigs by sampling lower-crown branch tips of the same trees. We found that the probability of detecting wool with ball sampling increased with number of ball samples per tree, with number of trees per simulated stand, and with increasing incidence of ovisacs in the lower crown. When sampling an individual tree, we found that 20 ball samples per tree achieved a targeted precision level of 0.75, but when sampling a stand, we found that 10 ball samples per tree took the least time for the range of simulated A. tsugae infestations we tested. These sample sizes are recommended for detection of A. tsugae infestations on an individual tree and in a hemlock stand.



1990 ◽  
Vol 52 (2) ◽  
pp. 117-119 ◽  
Author(s):  
J. K. Morrison ◽  
C. L. Coyle ◽  
S. E. Bertoni


2012 ◽  
Vol 58 (5) ◽  
pp. 513-522 ◽  
Author(s):  
Luke Worsham ◽  
Daniel Markewitz ◽  
Nathan P. Nibbelink ◽  
Larry T. West


1976 ◽  
Vol 22 (4) ◽  
pp. 435-436
Author(s):  
B. F. Eldridge


1976 ◽  
Vol 1 (3) ◽  
pp. 283-284
Author(s):  
B.R. Laurence


2018 ◽  
Vol 70 (3) ◽  
pp. 589-598
Author(s):  
Milos Ilic ◽  
Ruzica Igic ◽  
Mirjana Cuk ◽  
Dragana Vukov

Because of the high importance of bryophytes in forest ecosystems, it is necessary to develop standardized field sampling methodologies. The quadrat method is commonly used for bryophyte diversity and distribution pattern surveys. Quadrat size and the position of quadrats within the studied area have a significant influence on different analyses. The aim of the present study was to define the minimum quadrat size appropriate for sampling ground bryophytes in temperate beech forests, to compare two different field sampling methods for research on ground bryophytes, the random and microcoenose methods; and to test the adequacy of the microcoenose sampling method in temperate beech forests. Research was carried out on Fruska Gora mountain (Serbia) at four different sites. All sites contained temperate broadleaf forest vegetation, predominantly Fagus sylvatica, but also included various other tree species. Systematic sampling based on nested quadrats was used to determine the minimum sampling area. Random sampling was performed using 10 or 20 microplots (minimum area quadrat), randomly located within 10x10 m plots. Microcoenose sampling is a systematic sampling method based on the fact that every bryophyte fragment on the forest floor is a separate microcoenose. These methods were compared using the following criteria: species richness; Shannon?s diversity index and evenness measure; coverage of dominant species, and the time needed for sampling. The microcoenose sampling method has proven to be highly applicable in temperate beech forests in terms of species richness and diversity, in contrast to random sampling, which was not suitable for bryophyte flora with a patchy distribution.



2009 ◽  
pp. 329-329-10
Author(s):  
KN Kontopanos ◽  
ES Williams




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