WorldCat Identities

Nagtegaal, D. A. (Dick A.)

Overview
Works: 46 works in 141 publications in 1 language and 1,090 library holdings
Genres: Conference papers and proceedings 
Roles: Author, Editor
Classifications: SH223, 597.58
Publication Timeline
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Most widely held works by D. A Nagtegaal
Identification and description of assemblages of some commercially important rockfishes (Sebastes spp.) off British Columbia by D. A Nagtegaal( Book )

9 editions published between 1982 and 1983 in English and held by 48 WorldCat member libraries worldwide

The 1977-1978 commercial catch statistics were analyzed to determine if assemblages existed among some of the commercially important rockfishes (Sebastes spp.) and if these assemblages persisted over time. Initially, the catch statistics were analyzed to determine bathymetric, geographic, and seasonal distribution. Cluster analysis and a relative catch proportion index were used to identify and describe assemblages, and covariance analysis was used to determine if assemblages persisted over time
A comparison of the results of the 1998 Georgia Strait creel survey with an independent observer program by R. E Diewert( Book )

3 editions published in 2005 in English and held by 40 WorldCat member libraries worldwide

The effects of water release strategies on chinook returning to the Cowichan River and the Nanaimo River by N. K Hop Wo( Book )

2 editions published in 2005 in English and held by 40 WorldCat member libraries worldwide

Adult chinook escapement assessment conducted on the Cowichan River during 2004 by D. A Nagtegaal( Book )

2 editions published in 2006 in English and held by 38 WorldCat member libraries worldwide

In 2004, the Biological Sciences Branch, in the Pacific Biological Station, continued a study of the Chinook salmon (Oncorhynchus tshawytscha) productivity in the Cowichan River. This in-depth escapement assessment project has been in place since 1988. Major components of this study included: enumerating spawners and total return, estimating First Nations food fish catch, recording hatchery broodstock removals, and collecting biological, environmental and coded-wire tag data. Population estimates for adult and jack Chinook were determined based on the fence count since this was considered to be the most accurate enumeration method. A carcass mark-recapture study was conducted on the spawning grounds to augment the collection of biological data and to supplement the fence count population estimate
Adult chinook escapement assessment conducted on the Cowichan River during 2003 by D. A Nagtegaal( Book )

2 editions published in 2006 in English and held by 37 WorldCat member libraries worldwide

In 2003, the Biological Sciences Branch, Pacific Biological Station, continued a study of chinook salmon productivity in the Cowichan River. This in-depth escapement project has been in place since 1988. Major components of this study included: enumerating spawners and total returns, estimating First Nations food fish catch, recording hatchery broodstock removals, and collecting biological, environmental and coded-wire tag data. Population estimates for adult and jack chinook were determined based on the fence count since this was considered to be the most accurate enumeration method. A carcass mark-recapture study was conducted on the spawning grounds to augment the collection of biological data and to supplement the fence count population estimate
Adult chinook escapement assessment conducted on the Nanaimo River during 2002 by E. W Carter( Book )

1 edition published in 2004 in English and held by 36 WorldCat member libraries worldwide

A productivity study of chinook salmon in the Nanaimo River which enumerated returning chinook, collected biological and coded-wire tag data, and estimated returning chinook using a carcass mark-recapture project as a comparison. Also examined was the effects of a water management plan implemented in 1989 to aid the upstream movement of fall chinook
Juvenile chinook production in the Cowichan River, 1998 by D. A Nagtegaal( Book )

4 editions published in 1999 in English and held by 36 WorldCat member libraries worldwide

In 1991, Fisheries and Oceans Canada (DFO), Pacific Biological Station began a study of juvenile chinook salmon (Oncorhynchus tshawytscha) productivity in the Cowichan River. The 1998 study is concerned primarily with the enumeration and out-migration timing of naturally-reared chinook juveniles. The estimated production of naturally-reared chinook juveniles from the 1997 brood year was 1,638,198 (95% Confidence limit 1,376,097 -1,900,324). There were three distinct peaks in the outmigration of naturally-reared chinook. The first occurred March 15 -17, the second and largest occurred March 19 -21 and the final peak occurred March 23 -28. The release of chinook from the Cowichan River hatchery totalled 262,675. Of these, 160,924 hatchery-reared chinook were released above the trapping site. Trapping results maintain that most hatchery-reared chinook migrate to the Cowichan estuary within one week of release. Interaction between naturally-reared and hatchery-reared chinook juveniles is therefore believed to be limited
Adult chinook escapement estimate conducted on the Nanaimo River during 1997 by E. W Carter( Book )

5 editions published in 1999 in English and held by 36 WorldCat member libraries worldwide

In 1997, Fisheries and Oceans Canada in co-operation with Nanaimo First Nation continued a productivity study of chinook salmon (Oncorhynchus tshawytscha) in the Nanaimo River. Areas ofconcentration for this study included: i) enumeration of returning chinook; ii) collection of biological and coded-wire tag (CWT) data; and iii) estimation of returning chinook using a carcass mark-recapture project as a comparison. Based on the enumeration fence count, we estimated the total return ofadult fall chinook to the Nanaimo River to be 1290 in 1997. After removal ofbroodstock by the hatchery, the number ofnatural spawners was estimated at 1118 for fall chinook. Based on swim survey and overflight information, the total return ofthe spring chinook stock was estimated to be 600 adult chinook. We also looked at the effects of a water management plan implemented in 1989 to aid the upstream movement of fall chinook
Juvenile chinook production in the Nanaimo River, 2000-2002 by N. K Hop Wo( Book )

2 editions published in 2005 in English and held by 35 WorldCat member libraries worldwide

Proceedings of the 2000 Creel Workshop by D. A Nagtegaal( Book )

5 editions published in 2001 in English and held by 34 WorldCat member libraries worldwide

This report documents results from a workshop on creel surveys held at the Coast Bastion Hotel in Nanaimo, B.C., from 15-17 Feb 2000. Approximately 30 people attended the workshop and 22 presentations were given in two sessions. A variety of creel programs are conducted from the West Coast of Washington State to the North Coast of British Columbia and these were previewed in the Introductory Session. Many data requirements were discussed as they related to stock assessment as well as fish management. Although the Georgia Strait Creel Survey was originally designed to collect primarily salmon catch data, the goals of the survey are expanding to address non-salmon informational requirements such as groundfish, rockfish, and shellfish. The issue of shifting effort from salmon to non-salmon species needs to be documented and monitored closely in the future. The importance of a regionally accessible database was discussed and it was suggested that this database include changes to study design and environmental conditions as well as catch and effort data. It was pointed out that in order to maintain continued public participation in the creel survey the program must be well documented and defensible. The primary goals of this workshop were to: 1) conduct an extemal review of the survey design and methodology for the GSTR creel since this is the design which most marine creel surveys in the Pacific Region are modelled after and 2) determine if survey robustness could be maintained while expanding the role of the survey. The reviews were discussed in the second session and reviewers determined that survey design and methodology for the GSTR was good and several helpful comments and suggestions were provided. It was pointed out that interview effort must be maintained at or above cun-ent levels to ensure activity pattem integrity. The accurate construction of activity profiles is clitical and potential en-ors involving angler bias and recall could be greater than originally thought. As a result more time should be spent determining the effort profile as well as to address "pocket fisheries". The use of non-randomized overflights in creel surveys was discussed and it was concluded that counts did not have to be random. It is important however that overflight counts are conducted at stable (close to peak) rather than rapidly changing periods. Further recommendations included using a telephone-access survey to provide a comparative tool. Assumptions made concerning landing sites, boat types, and areas of effort could be verified using a telephone survey. It was recommended that a required level of precision be established as well as to which variables these levels would apply. Precision levels should meet management requirements and fall within budget capabilities of the creel program
A preliminary report on the adult chinook salmon escapement study conducted on the Nanaimo River during 1996 by E. W Carter( Book )

3 editions published in 1998 in English and held by 33 WorldCat member libraries worldwide

In 1996, Fisheries and Oceans Canada in co-operation with Nanaimo First Nation continued a productivity study of chinook salmon (Oncorhynchus tshawytscha) in the Nanaimo River. Areas of concentration for this study included: i) enumeration of returning chinook; ii) collection of biological and coded-wire tag (CWT) data; iii) estimation of returning chinook using a carcass mark-recapture project as a comparison. Based on the enumeration fence count, we estimated the total return of adult fall chinook to the Nanaimo River to be 1247 in 1996. After removal of broodstock by the hatchery, the number of natural spawners was estimated at 990 for fall chinook. Based on swim survey information in the upper Nanaimo River, the total return of the spring chinook stock was estimated to be 600 adult chinook. We also looked at the effects of a water management plan implemented in 1989 to aid the upstream movement off all chinook
A preliminary report on juvenile chinook production in the Cowichan River, 1999 by D. A Nagtegaal( Book )

4 editions published in 2000 in English and held by 32 WorldCat member libraries worldwide

A preliminary report on the adult chinook productivity study conducted on the Nanaimo River during 1995 by E. W Carter( Book )

4 editions published in 1997 in English and held by 32 WorldCat member libraries worldwide

The purpose of this report is to present the results and describe the methodology of the adult enumeration study of the fall chinook stock on the Nanaimo River, British Columbia, and to summarize additional survey data collected on the spring stock on the river during fall 1995. Fall stock escapement was estimated using an enumeration of salmon at a counting fence and carcass mark-recapture studies. Spring stocks were estimated using swim survey and overflight information. The report also examines the effects of a water management plan implemented in 1989 to aid the upstream movement of fall chinook
Results of rotary auger trap sampling in the Nanaimo River, 1998 by D. A Nagtegaal( Book )

4 editions published in 1998 in English and held by 32 WorldCat member libraries worldwide

Results of the Chinook Assessment Study conducted on the Klinaklini River during 1997 by D. A Nagtegaal( Book )

6 editions published in 1998 in English and held by 32 WorldCat member libraries worldwide

In 1997, the Biological Sciences Branch, Pacific Biological Station, conducted a study of chinook salmon (Oncorhynchus tshawytscha) productivity in th~ Klinaklini River. Major components ofthis study include: i) enumeration and distribution ofspawners, ii) collection ofbiological and environmental information, and iii) evaluation offishwheel as a stock assessment tool. A counting fence was constructed on Mussel Creek, a live mark-recapture study was conducted by tagging chiriook at the fishwheel and recapturing fish at a fence on Mussel Creek, a radio telemetry study was conducted to determine spawner distribution, and a rotary screw trap was used to determine downstream migration ofjuveniles. Total return ofadult chinook to the Klinaklini River was estimated to be 4,906 (95% CL: 3,791 - 6,021) in 1997. Spawner distribution within the watershed was determined to be 79% in Mussel Cr., 12% in Icy Cr., and 9% in Dice Cr. The majority ofchinook spawners were aged as three and four year olds and approximately 60% ofthe chinook caught in the fishwheel were considered to be stream-type
Results of a marine recreational chinook and coho catch and release mortality study conducted in the lower Strait of Georgia during 2001 by R. E Diewert( Book )

4 editions published in 2002 in English and held by 31 WorldCat member libraries worldwide

Strait of Georgia and Northern Vancouver Island sport fishery creel survey statistics for salmon and groundfish, 1999 by D. C Hardie( Book )

3 editions published in 2001 in English and held by 30 WorldCat member libraries worldwide

A preliminary report on juvenile chinook production of the Cowichan River, 1996 by D. A Nagtegaal( Book )

4 editions published between 1997 and 1998 in English and held by 4 WorldCat member libraries worldwide

In 1996, the Dept. of Fisheries and Oceans, Pacific Biological Station undertook a study of juvenile chinook salmon (Oncorhyncus tshawytscha) productivity in the Cowichan River. This report presents the results of the juvenile chinook production study, which includes timing of the chinook fry migration, estimates of the abundance of naturally reared chinook, juvenile chinook growth rates, and the interaction between hatchery produced and naturally reared chinook juveniles. Incidental catches of other species were also recorded
Catches and trawl locations of M/V BLUE WATERS during rockfish exploration and assessment cruise to the West Coast of the Queen Charlotte Islands, 1979 by D. A Nagtegaal( Book )

2 editions published in 1980 in English and held by 3 WorldCat member libraries worldwide

 
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Alternative Names
Nagtegaal, Dick

Languages
English (69)