NOAA Technical Memorandum NMFS

This TM series is used for documentation and timely communication of

preliminary results, interim reports, or special purpose information. The TMs

have not received complete formal review, editorial control, or detailed

editing.

MARCH 1997

APPLICATION OF ACOUSTIC AND ARCHIVAL

TAGS TO ASSESS ESTUARINE, NEARSHORE, AND

OFFSHORE HABITAT UTILIZATION AND

MOVEMENT BY SALMONIDS

Proceedings of a workshop held 10-11 September, 1996

Seattle, Washington

Edited by

George W. Boehlert

Pacific Fisheries Environmental Group

Southwest Fisheries Science Center

1352 Lighthouse Avenue, Pacific Grove, CA 93950-2097

NOAA-TM-NMFS-SWFSC-236

U.S. Department of Commerce

William Daley, Secretary

National Oceanic and Atmospheric Administration

D. James Baker, Under Secretary for Oceans and Atmosphere

National Marine Fisheries Service

Rolland A. Schmitten, Assistant Administrator for Fisheries
Application of acoustic and archival tags to assess estuarine,

nearshore, and offshore habitat utilization and movement by

salmonids

Executive Summary

Salmonid stocks on the west coast are in trouble and concerns have been expressed by

scientific, environmental, and fishing communities. Causes of population declines are complex;

variations in freshwater flow, dams, habitat degradation, hatchery practices, climate variability,

and ocean conditions may all play a role. The contribution of the estuary and ocean to variations in 

salmonid survival remains poorly known. Understanding this role and how it varies with

changing environmental conditions will require improved knowledge of movements and habitat

utilization during different life history stages. This volume is the report of a workshop organized

in Seattle in September, 1996 to examine the means by which new tagging technologies,

principally acoustic and archival tags, can contribute to our understanding of these questions.

Tag technology is a relatively fast-moving field and application to salmonids may require

modified designs; thus, it was timely to convene this workshop to promote communication among

scientists interested in salmon and the technologists and engineers developing tags. The general

goal of the workshop was to address the potential application of acoustic and data logging tags to

describe the utilization of estuarine and ocean environments by salmon during different life-history

stages to better understand the role of environmental factors in movements and survival. 

The workshop report includes papers presented at the meeting, including three introductory

papers which lay out perspectives on the important research needs, experience papers describing

research work on topics dealing with applications of acoustic or data logging tags and associated

research, and technology papers on the status and evaluation of tags, and contributed abstracts on

pertinent biology and technology. A written summary of two discussion groups, one on biology,

ecology, and oceanography and the second on technology, is augmented by a series of workshop

recommendations.

The participants in the workshop developed 17 recommendations. In the biology-related

recommendations, a demonstration project using existing tags was given a high priority. 

Participants strongly supported research to describe movements and habitat utilization of i) young

fish immediately after the transition from estuarine to marine waters, ii) young fish within the

estuary, and iii) adults moving into the estuary on the return migration. Application of geolocating

tags in the open ocean was also given high priority for west coast chinook and coho salmon,

sockeye salmon, and steelhead. In the technology-related recommendations, most important was

the calibration and verification of tag precision and accuracy and continued miniaturization of tags,

the latter reflecting the desire to extend this research to earlier life history stages of salmonids. 

Also stressed was the need to evaluate effects of these long-term tags on the fish and to improve

geolocating algorithms.

New technologies in tagging have the potential to address several key questions that hinder our

ability to evaluate the variability in salmon survival. It is our hope that this volume will foster

communication and promote the development of technologies specific to address these questions in

salmon.

i
Workshop Report: 

Application of acoustic and archival tags to assess estuarine,

nearshore, and offshore habitat utilization and movement by

salmonids

TABLE OF CONTENTS

Executive Summary i

Application of acoustic and archival tags to assess estuarine, 1

nearshore, and offshore habitat utilization by salmonids: 

Introduction and objectives of the workshop

George Boehlert

Introductory Papers 7

Estuarine life history of salmonids: Potential insights from tagging 8

studies Robert Emmett and Earl Dawley

Habitat utilization and movements of salmonids in coastal waters 11

W.G. Pearcy

Ocean studies using “smart” & hydroacoustic tags 13

David Welch

Experience Papers 15

Acoustic and archival tagging work on salmonids in Japan 16

Miki Ogura

Atlantic salmon data requirements and data-logging tags 28

Kevin Friedland 

Ultrasonic tracking of salmonids: selected experiences and perspectives 28

Thomas Quinn

New technologies for measuring tag induced stress: determining 29

competency over time Paul Siri

NerkaSim: A micro-computer model of the Northeast Pacific 29

Ocean and Bering Sea for simulating sockeye salmon migrations and growth.

Michael Healey

Computer simulations of sockeye salmon return migrations: Results yielding 30

testable hypotheses of migration behaviour and the effects of the marine 

environment on migration paths that plead for archival tagging experiments.

Keith A.Thomson

Auke Bay Laboratory’s Ocean Carrying Capacity Research Program 31

Jack Helle

Technology Papers 33

Benchmark tests of accuracy of two archival tags 34

A.Peter Klimley and Charles Holloway

Progress on geoposition estimation and assessing archival tag accuracy 34

David Welch

Development of a small format temperature logging tag 35

Kevin Friedland

i i
Tagging technology from VEMCO Limited 35

Fred Voegeli

Archival tag technology from Northwest Marine Technology, Inc. 36

Phil Ekstrom

Lotek Marine Technologies Inc.-- Salmonid acoustic and archival 37

tags; current products and emerging technologies

Keith Stoodley

Discussion Groups 39

Salmonid biology, ecology, and oceanography: What can be learned 40

from acoustic and data logging tags?

Discussion Leader: Kate Myers

Current and needed technology for application of acoustic and 44

recording tags to salmonids

Discussion Leader: Kevin Friedland

Workshop Recommendations 46

Salmonid biology, ecology, and oceanography 47

Technology needs for salmon tagging 48

Evaluation of workshop recommendations 49

Appendices

1. Contributed Abstracts 51

Tracking of Atlantic salmon (Salmo salar L.) and sea trout 52

(Salmo trutta L.) with Icelandic data storage tags

Johannes Sturlaugsson and Sigmar Gudbjornsson

Rejection of internal telemetry transmitters by shortnose sturgeon 54

Boyd Kynard and Micah Kieffer

Tracking of post-smolt Atlantic salmon into coastal areas of the Bay of Fundy 55

Gilles L. Lacroix

Feasibility of long term intramuscular implantation of archival 56

tags in large pelagic fishes Richard Brill, Katherine Cousins and Pierre Kleiber

The use of acoustic and data storage tags in establishing the role of 57

the tidal streams in plaice migration in the southern North Sea.

J.D. Metcalfe and G.P. Arnold

Temperature and data loggers from Onset Computer Corporation 58

Mark McSherry

Data archival and satellite-linked tags from Wildlife Computers 58

Roger Hill

Acoustic tags available from SONOTRONICS 59

Marlin J. Gregor

Zelcon Technic wildlife tracking systems 60

Ana Nicolau

2. Workshop Participants 61

iii
Acoustic and Archival Tags: Applications to Salmonid Research 1

Application of acoustic and archival tags to assess estuarine, nearshore, and

offshore habitat utilization by salmonids: Introduction and objectives of the

workshop

George Boehlert, NMFS Southwest Fisheries Science Center, Pacific Fisheries Environmental

Group, 1352 Lighthouse Avenue, Pacific Grove, CA 93950-2097

Introduction

Declining survival of several salmonid stocks on

the west coast has raised alarms in the scientific,

environmental, and fishing communities. Central

California coho salmon have been listed as threatened

under the Endangered Species Act, and other stocks in

Northern California and Oregon are being considered for

listing. The causes of declining stocks are complex,

but have been attributed to a variety of factors,

including variations in freshwater flow, dams, habitat

degradation, hatchery practices, climate variability, and

ocean conditions (National Research Council 1996). In

March, 1996, a workshop was held in Newport,

Oregon, to examine the role of estuarine and ocean

survival in the recent declines of west coast salmon

stocks (Emmett and Schiewe 1997). This topic had not

been addressed in a coordinated fashion since a similar

workshop held over a decade earlier (Pearcy 1984),

although recent knowledge and important hypotheses

have been summarized in a monograph (Pearcy 1992). 

Fundamental to understanding variability in

survival in the estuary and ocean is improved knowledge

of movements and habitat utilization during different

life history stages, including the relationship to

environmental variability. Most knowledge of ocean

habitat utilization comes from experimental net capture

data (Pearcy and Fisher 1988), traditional tagging

studies (including coded wire tags and other tags; Myers

et al. 1996), fisheries data (French and Bakkala 1974;

Welch et al. 1995), experimental fishing (Pearcy et al.

1984), acoustic tagging studies (Ogura and Ishida 1995;

Quinn et al. 1989) and trophic studies (Welch and

Parsons 1993). Although a great deal of research has

been done on the habitat preferences of salmonids in

freshwater systems, assessment of thermal preferenda,

diel variability in depth, and directed movements in

response to environmental variability in the ocean are

largely inferred from catch and model data (Healey et al.

1990; Thomson et al. 1994; Welch et al. 1995;

Beamish et al. 1995), save relatively short-term studies

with acoustic tags (summarized in Ogura, this volume).

How salmon utilize their environment on varying

scales was a major point of discussion at the Newport

workshop that cut across all working groups (Emmett

and Schiewe 1997). As examples, the nearshore

working group expressed concern about the movement

and habitat residence patterns in the first few days after

ocean entry; similar studies are underway with Atlantic

salmon (see LaCroix, this volume). At broader scales,

the offshore group identified as high priority questions

the distribution and migration patterns at sea and the

manner in which currents and other physical factors

influence them. Both early models of fish movement

(French and Bakkala 1974) and recent, more

sophisticated ones (Thomson et al. 1994; Dat et al.

1995) rely on a variety of assumptions about fish

behavior at scales that remain to be studied in sufficient

detail to carefully test the predicted movements. Several

participants at the Newport workshop identified the need

for applications of new tagging technology to address

these and other questions dealing with estuarine and

ocean survival, and this workshop has been organized to

address these questions.

Tagging programs and tag technology

Tagging is a standardized technique in fisheries

science (Neilson 1992) and has been an important

component of studies with salmon. A variety of

salmon databases on tagging exist; the ocean tagging

database (Myers et al. 1996) and the coded wire tag

program (Johnson 1990) provide good examples of the

large scale (and international scope) on which salmon

tagging is undertaken. The importance and magnitude

of these tagging projects have made salmon the focus of

many developments in tag technology, such as the

coded wire tag (Bergman et al. 1968), the passive

integrated transponder (PIT) tag (Prentice et al. 1990),

and visible implant tags (Blankenship and Tipping

1993; Bonneau et al. 1995). Most of these tags have

been designed for mass marking and generally address

questions dealing with the population level (fish

movement, return rates, or stock integrity). Longer
2 Acoustic and Archival Tags: Applications to Salmonid Research

range tracking, including satellite-linked systems, have

been used in freshwater with radio telemetry (Eiler

1995), but this system will not operate in saline waters

of estuarine and marine systems. 

Acoustic tags can be applied to far fewer fish, are

labor intensive to apply and monitor, but provide

detailed information. In the marine environment,

acoustic tags have been extensively applied to large

fish, including tunas, billfishes, sharks, and deep-sea

grenadiers (Carey and Robison 1981; Holland et al.

1990; Cayre 1991; Klimley et al. 1988; Priede et al.

1990). Acoustic tags have the capability to measure a

wide variety of parameters, including depth, swimming

speed, tailbeat frequency, and internal body temperature.

Given that most studies with acoustic tags involve

vessels following individual fish, additional parameters

(geographic location, bottom depth, ocean currents,

thermal profiles, salinity) can be taken in the general

vicinity. Acoustic tags have been applied to salmon

(Stasko et al. 1973; Quinn et al. 1989; Ogura and Ishida

1992, 1995; LaCroix, this volume). Although these

tags have provided important insights into the ecology

and habitat utilization of the salmon studied, they have

generally required that individual fish be followed,

resulting in small numbers of observations and

typically short records from each tag. Unfortunately,

these short records create concerns about whether

observed behavior is normal. With moderate to large

tunas and tag placement outside the body, Holland et al.

(1990) found no differences in behavior between early in

the record and after 6 days, when the fish was relocated.

Contrary to this result, however, was the variation in

behavior observed in chum salmon shortly after tagging

in a long data record (see Ogura, this volume, Figure 9).

Miniaturization and newly developed technologies in

tagging may allow following multiple fish as well as

recording data and dumping it via an acoustic link to a

tracking vessel or to a remote listening station (see

Voegeli, this volume), possibly through an array of

moored buoys (see Lacroix, this volume. This type of

development may help with duration of the record and

the numbers of tags that can be deployed.

The newest technology is data logging (archival)

tags. The most important issues in the dynamics of

tuna movements were addressed by Hunter et al. (1986),

who identified application of data logging tags as a high

priority to determine the horizontal and vertical

movements of tuna over long periods. A principal

problem has been the need to recover the tagged animal

to retrieve the tag and its contained data; thus, most

studies concentrate on fish where tag return rates are

high. Generally, data logging tag development has been

gradual and marked by continually improved technology

and decreasing size. Early tags were large and had a

reduced parameter set. Long duration applications of

data recording tags to marine mammals, providing time,

depth, and temperature data, revealed previously

unknown information about foraging, dive depths, and

dive duration, with tagging periods up to 145 days

(Delong and Stewart 1991; Bovent et al. 1996). It

should be noted, however, that data logging tags record

only the environment which the fish experienced or

selected, which is important information in itself;

missing are data on the environmental conditions that

the fish avoided. Although this may be inferred from

climatological ocean records in the region, nearby

moored buoys, remote sensing, or ocean models, higher

resolution of this information may require simultaneous

monitoring of the physical environment.

The first application of data logging tags on

salmon recorded time and depth over a period of some

23 days on chum salmon and provided intriguing

results. Although short term behavior may be affected

by the trauma of tagging, data from later in the record

demonstrated a well-defined pattern of diel movement

(see Ogura, this volume, Figure 9). Time-depth

recording tags have also been applied to returning adult

Atlantic salmon and sea trout in Iceland (Sturlaugsson

1995; Sturlaugsson and Gudbjornsson, this volume).

Geolocating tags, which typically add light as a

measured parameter and then use an algorithm based on

time and daylength (measuring sunrise and sunset), are

also under development and obviously highly desirable

for measuring migrations. At present, the geolocating

tags have been applied principally to tunas (Gunn et al.

1994; Ekstrom, this volume) and preliminary results

have provided intriguing insights to the migration

pattern of southern bluefin tuna (J. Gunn, CSIRO,

personal communication), as suggested by Hunter et al.

(1986). Although most geolocating tags are at present

too large for application to salmon, sizes are

continually being reduced. It is also possible to

estimate locations through measurement and simulation

of ocean thermal conditions, similar to the approach for

plaice movements in the North Sea (Metcalfe and

Arnold, this volume); the accuracy of the location

information, however, may be questionable in an ocean

environment that varies interannually.
Acoustic and Archival Tags: Applications to Salmonid Research 3

Two concerns must be taken into account for

application of data logging tags. First is the accuracy

and precision of the measured parameters and the

consistency between tags. Miniaturized sensors may be

subject to drift over time, so careful evaluation of the

tags is highly important. Second is the capability of

the fish to carry the tags. For short-term acoustic

tagging of durations less than 5 days, histopathological

effects may not be an overriding concern, although tag

effects on behavior (from capture, handling,

hydrodynamic drag, or other trauma) obviously are. For

longer tagging durations, however, it is critical to

minimize the effects of tagging, which can affect fish

health, swimming ability, or vulnerability to predation.

Tag shedding or extrusion must also be evaluated. In

traditional tagging programs, significant effort has gone

into evaluating tag effects (Roberts et al. 1973; Neilson

1992; Blankenship and Tipping 1993) and tag loss

(Wetherall 1982). With acoustic tags, Quinn et al.

(1989) demonstrated that returns and travel rate of

sockeye salmon did not differ from those tagged with

disk tags alone. Other experiments with salmonids

have shown effects on behavior (Mellas and Haynes

1985) and dramatic, size-dependent effects of ultrasonic

tags on growth (Greenstreet and Morgan 1989). Data

logging tags have several characteristics that mandate

careful evaluation of their effects before a serious

tagging program is undertaken. The tags are relatively

large, will likely be on the fish for long periods, and are

expensive; preliminary testing of intramuscular

implantation in tunas has been promising (see Brill et

al., this volume). Because the probability of tag return

may be low, it is important to assure the best match of

the tag to the fish to maximize chances of recovery (see

Siri, this volume).

Objectives of the workshop

New tagging technology has the potential to reveal

important information on salmonid movement and

habitat utilization. Both short-term acoustic tags and

recording, or archival tags may be beneficially applied

to address specific topics of interest. Tag technology is

a relatively fast-moving field and several salmonid

biologists are interested in applying these technologies;

thus, it was timely to convene this workshop to

promote communication among scientists interested in

salmon and the technologists and engineers developing

tags. The general goal of the workshop was to address

the potential application of acoustic and data logging

tags to describe the utilization of estuarine and ocean

environments by salmon during different life-history

stages to better understand the role of environmental

factors in movements and survival. 

The workshop took place 10-11 September, 1996,

at the NOAA Pacific Marine Environmental Laboratory

in Seattle. Before the meeting, participants were

provided with a series of questions to stimulate thought

on the focus of the workshop, including the following:

Biology, Ecology, and Oceanography

 • What is known about the movements of salmon in

estuarine, nearshore, and open ocean habitats at

varying scales?

 • How can we best measure the role of environmental

and habitat factors in salmon habitat utilization and

movements?

 • What are the most important species, life history

stages, habitats, and geographic scales to address

these questions and what can be gained from the

application of acoustic and data logging tags?

 • What priority order should be given these research

issues?

 • What are current or planned research activities

associated with application of tags?

Technology

 • What is the current state of acoustic and data

logging tag development as it relates to application

in salmonids?

 • What specific developmental engineering work

should be undertaken to make these tags more

suitable for application to different salmonid life

history stages?

 • What is the capacity of salmonids to carry these

tags?

 • What are the priorities for tag development?

Organization of the workshop report

The workshop report generally follows the agenda

of the meeting. Three introductory papers were

presented to lay out perspectives on the important

research needs in estuarine, nearshore, and oceanic

environments. “Experience” papers describe research

work by participants at the workshop on topics dealing

with applications of acoustic or data logging tags and

associated research. “Technology” papers were presented

on the status and evaluation of tags. The abstracts of

these presented papers are followed by a written

summary of two discussion groups, one on biology,
4 Acoustic and Archival Tags: Applications to Salmonid Research

ecology, and oceanography and the second on

technology, held sequentially so that all participants

could contribute. The discussion groups addressed the

questions outlined above plus other topics that arose

during presentation of the papers. Arising from the

discussion groups were a series of recommendations;

these were circulated after the meeting for further

discussion and elaboration, and finally voted on to

assign priority order. Finally, three appendices include

i) contributed abstracts (pertinent abstracts on biology

and technology not presented at the meeting), ii) the

meeting agenda, and iii) the list of participants at the

meeting.

Acknowledgements

Travel funding and support for this meeting was

provided by the NMFS Office of Protected Resources.

For use of the meeting room facilities, we thank Dr.

Eddie Bernard, Director of PMEL. I thank R.W. Brill

and W.G. Pearcy for comments on an earlier draft of

this introductory manuscript and R.D. Brodeur for

comments on the entire workshop report.

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6 Acoustic and Archival Tags: Applications to Salmonid Research

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Upper thermal limits on the oceanic distribution of

Pacific salmon (Oncorhynchus spp.) in the spring.

Canadian Journal of Fisheries and Aquatic Sciences. 52:

489-503.

Wetherall, J. A. 1982. Analysis of double-tagging

experiments. Fish. Bull., U.S. 80: 687-703.
Acoustic and Archival Tags: Applications to Salmonid Research 7

Introductory Papers

The following three abstracts reflect three papers presented to provide a

perspective to the workshop on the three principal habitats where research using

acoustic and data logging tags is deemed useful and to describe the kinds of data

that are most important to understanding salmonid utilization of these habitats. 
8 Acoustic and Archival Tags: Applications to Salmonid Research

Estuarine Life History of Salmonids: Potential Insights From Tagging Studies

Robert Emmett and Earl Dawley, National Marine Fisheries Service Northwest Fisheries Science

Center, Coastal Zone and Estuarine Studies Division.

Studies by Reimers (1973), Simenstad et al. (1982)

and others have shown that estuarine rearing plays an

important role in salmonid life histories and can affect

the ocean survival of ocean-type chinook

(Oncorhynchus tshawytscha), pink (O. gorbuscha) and

chum (O. keta) salmon. In contrast, with the exception

of sea-run cutthroat trout (O. clarki), smolts which

migrate as yearlings and older [e.g., sockeye (O. nerka),

steelhead (O. mykiss), and (stream type) chinook

salmon] generally do not utilize estuaries extensively.

Despite these general migration and timing behaviors,

actual estuarine use varies by species or stock and 

appears to be mediated by water temperature, river flow,

food availability, and other factors. 

Although archival, acoustic, and radio tags may

answer many scientific questions related to the estuarine

and early ocean life history of salmonids, their large size

relative to the size of migrating salmon smolts limits

their potential (Table 1). Small subyearling smolts are

presently effectively tagged by small coded wire tags

(CWT) and passive integrated transponders (PIT) tags.

Table 1. Juvenile salmonid size, timing, peak migration period, and individual residence in West Coast estuaries.

Critical size is the minimum length required to survive ocean entry. Question marks indicate unknown or uncertain

information.

Species

Size during

migration (fork

length - mm)

Timing of

migration

Peak

migration

period

Individual

residence

(days)

Pink salmon 30-80 

critical size 45-55?

Early 

Feb- Jun

Late MarEarly May~2-60+

Chum salmon 30-100 Early Feb-Jul Late Marmid May4-32+

Chinook salmon

spring/summer

100-175 Jan-Jul 

Nov-Apr (Calif)

Apr-May 

Jan-Feb (Calif)

? limited?

Chinook salmon

fall

30-130 

critical size 80-90?

Jan-Dec Jun-Oct 10-60+

Chinook salmon

late fall

30-? Apr-Oct ? ?

Chinook salmon

winter

30-? Jun-Dec Aug-Sept. ?

Coho salmon 100-200 Mar-Jul May 6-40

Sockeye salmon 40-120 Apr-Jul May-Jun some rearing?

Steelhead 150-300 Apr-Jul May limited

Cutthroat trout 130-300 Feb-Oct Apr-Jul 1-150?

 
Acoustic and Archival Tags: Applications to Salmonid Research 9

Past smolt tagging studies with CWT and PIT tags

have provided valuable salmonid life history

information. For example, Dawley et al. (1986)

estimated smolt migration rates through the Columbia

River and defined timing of ocean entry based on

extensive sampling of smolts tagged with CWTs. They

also discovered that salmonids released farthest upriver

migrated the fastest, while those released closest to the

estuary migrated the slowest. Furthermore, they found

that subyearling chinook migrated the slowest (<4

km/day), and yearling and older smolts migrating much

faster (>10 km/day). They also found that some

salmonid stocks, such as ocean-type chinook salmon,

actually slowed their migration when they entered the

estuary.

Recovery of CWT and non-tagged smolts in the

Columbia River estuary by the National Marine

Fisheries Service (NMFS) during the Columbia River

Data Development Program found that, in general,

yearling salmonid smolts migrate in the main estuarine

channels and do not considerably slow their migrations.

However, at present little information is available that

reveals how long individual fish actually reside in

different estuarine habitats. 

Coded wire tag- and PIT-tag studies in the

Columbia River and other Pacific Northwest rivers have

also provided valuable information on variability in

ocean survival rates for salmonid smolts which migrate

at different times and sizes. For example, Matthews et

al. (1992) found that late migrating spring/summer

chinook salmon in 1990 returned as adults in

significantly higher numbers than earlier migrants

(Table 2). Evidently, ocean and estuarine environmental

conditions were favorable for salmonid survival during

that period, however, no data were collected to monitor

those environmental conditions. We do know that

timing of favorable ocean and estuarine conditions are

not always consistent from year to year. 

Development of very small archival or acoustic

tags that could record environmental data (salinity,

temperature, and depth) would be valuable in identifying

1) how long individual juvenile salmonids reside in

particular estuarine habitats, and 2) what environmental

factors influence their distribution. The recent

development of a surface trawl PIT tag detector by

NMFS promises to be a valuable tool for assessing

movements and survival of migrating juvenile

salmonids (Richard Ledgerwood, National Marine

Fisheries Service, Hammond, OR, Pers. comm., Sept.

1996). A recent study by Oregon State University

investigators using radio-tagged migrating juvenile

spring/summer chinook salmon in the lower Columbia

River, highlights the value of tagging studies. They

found that 90% of their study fish survived from

Bonneville Dam [river kilometer (Rkm) 200] to the

head of the estuary (Rkm 75) but about 30% of these

fish were lost in the estuary. They were able to find

most of the lost tags in nesting tern and cormorant

colonies (Larry Davis, Oregon State University, Fish

and Wildlife Dept., Corvallis, OR, Pers. comm, Sept.

1996). Although this study appears to identify the

intensity of bird predation on estuarine smolts, research

needs to be conducted to confirm that radio-tagged

juvenile salmonids are exhibiting normal migratory

behavior and are not unusually susceptible to avian

predation.

In conclusion, archival, acoustic, and radio tags offer a

wide range of effective methods for identifying

individual movements and behaviors relative to

estuarine and coastal environmental conditions, and

perhaps identify sources of mortality. However, these

tags will probably not provide answers to questions

concerning factors that limit estuarine and ocean

juvenile salmon survival for most populations. Studies

should be conducted that identify the physical and

biological conditions in estuarine and nearshore coastal

environments that facilitate high ocean survival. These

studies can effectively be conducted using serial releases

of CWT- or PIT-tagged groups of smolts with

concurrent measurements of physical and biological

conditions in estuarine and nearshore marine

environments. Data collected could be used to ensure

that hatchery fish are released at times that are optimal

for estuarine and ocean survival.

References

Dawley, E. M., R. D. Ledgerwood, T. H. Blahm, C.

W. Sims, J. T. Durkin, R. A. Kirn, A. E. Rankis, G.

E. Monan, and F. J. Ossiander. 1986. Migrational

characteristics, biological observations, and relative

survival of juvenile salmonids entering the Columbia

River estuary, 1966-1983. Report to Bonneville Power

Administration, Contract DE-A179-84BP39652, 256 p.

(Available from Northwest Fisheries Science Center,

2725 Montlake Blvd, E. Seattle, WA 98112-2097).
10 Acoustic and Archival Tags: Applications to Salmonid Research

Matthews, G. M., S. Achord, J. R. Harmon, O. W.

Johnson, D. M. Marsh, B. P. Sandford, N. N. Paasch,

K. W. McIntyre, and K. L. Thomas. 1992. Evaluation

of transportation of juvenile salmonids and related

research on the Columbia and Snake Rivers, 1990.

Report to the U.S. Army Corps of Engineers, Contract

DACW68-84-H0034, 51 p. (Available from Northwest

Fisheries Science Center, 2725 Montlake Blvd., E.,

Seattle, WA 98112-2097).

Reimers, P. E. 1973. The length of residence of

juvenile fall chinook salmon in Sixes River, Oregon.

Fish. Comm. Oreg., Res. Rep. 4, 43 p.

Simenstad, C. A., K. L. Fresh, and E. O. Salo. 1982.

The role of Puget Sound and Washington coastal

estuaries in the life history of Pacific salmon: an

unappreciated function. In V. S. Kennedy (editor),

Estuarine comparisons, p. 343-364. Academic Press,

NY.

Table 2. Adult returns to Lower Granite Dam of spring/summer chinook salmon (Oncorhynchus tshawytscha)

smolts marked and transported from the dam in 1990. Data taken from Matthews et al. 1992.

Dates marked Number of smolts

marked

Total adult

return estimates

N

%

13-18 Apr 5,938 Hatchery 23 0.40

1,062 Wild 5 0.05

18-21 Apr 6,218 Hatchery 18 0.30

782 Wild 5 0.60

21-25 Apr 6,256 Hatchery 25 0.40

744 Wild 18 2.40

25 Apr-2 May 6,039 Hatchery 30 0.50

961 Wild 5 0.50

2-14 May 6,203 Hatchery 30 0.50

797 Wild 23 2.90

14-29 May 4,857 Hatchery 85 1.80

2,143 Wild 58 2.70

29 May-8 Jun 1,177 Hatchery 25 2.10

1,531 Wild 63 4.10

Totals 36,688 Hatchery 235 0.60

8,020 Wild 175 2.20

Grand Total 44,708 410 0.90
Acoustic and Archival Tags: Applications to Salmonid Research 11

Habitat Utilization and Movements of Salmonids in Coastal Waters

W. G. Pearcy, Oregon State University, College Of Oceanography, Corvallis, OR 97331

Introduction

 All anadromous salmonids inhabit coastal waters

where they reside during a portion of their early life

history. Many coho and chinook stocks never leave

nearshore waters and spend their entire ocean life there.

Other species, such as pink, chum and sockeye salmon

and steelhead, leave coastal waters and migrate into the

oceanic zone of the subarctic Pacific, where they feed

and mature, and then return to coastal seas on their

spawning migrations.

 Early marine life of salmonids is thought to be a

critical period in the life history, when survival rates are

high and variable and when recruitment to fisheries is

determined. Most fisheries are for mixed stocks of

salmon in coastal waters. These are two major reasons

for learning more about the coastal movements and

habitat utilization of salmonids.

General Questions

 Five sets of questions need to answered in order to

understand ocean factors that influence the growth,

survival, movements and habitat utilization of

salmonids:

1. What are the patterns of distribution and migration

of stocks in the ocean? Are they genetically controlled

or determined by the environment?

2. How are these patterns influenced by ocean

conditions, by physical processes such as fronts, eddies,

upwelling and currents, and by biological factors such

as food availability, competition and predation?

3. How are patterns of distribution and movements

related to subsequent growth and survival rates? Is

mortality highest in specific habitats?

4. What are the major causes of mortality? How

dependent are predation rates on the availability of other

forage species?

5. What are the effects of interactions among stocks on

growth and survival--between stocks that inhabit the

same ocean habitat or between hatchery and wild stocks

in a common ocean region?

What Have We Learned from Past

Research?

 From the millions of tags (coded-wire, disk, Floy,

thermal, etc.) much as been learned about the

movements, growth, and survival of salmonids between

release, usually at a hatchery facility, and recovery at a

hatchery or in a fishery. Examples were (1) the

recovery of maturing fish after tagging juvenile fish in

their first ocean year (Hartt and Dell 1986); (2) the

movements of OPI hatchery smolts during their first

summer in the ocean off Oregon and Washington

(Pearcy and Fisher 1988); and (3) the latitudinal

distribution in the ocean of the coded-wire tagged coho

released from hatcheries along the coast of the Northeast

Pacific (Weitkamp et. al. 1996).

 The advantages of these types of tags is that many

smolts can be marked before they enter the ocean.

Hence the number of returns are large enough for

statistical analyses. Often smolts can be marked over a

short period of time, and automated procedures can be

now used. The disadvantages are that only data on

release and recapture locations and times are provided,

and no intervening data. Little information is given on

short-term movements or habitat selection, and nothing

on vertical excursions.

 Ultrasonic tagging, on the other hand, has been used

to track a single fish over a period of hours or days, and

can provide data on vertical movements and temperature

selection (see for example Quinn and terHart 1987;

Quinn, this workshop). However, tracking with vessels

in the ocean is very expensive, and usually only one

fish can be tracked at a time, usually over relatively

short distances.

 Needed are tags that can be tracked or record

information on movements in three dimensions over

weeks or months. Ideally, smolts or post-smolts

should be tagged so that the origin of the fish is known

and the movements of specific stocks can be studied in

the coastal ocean during their juvenile life history and

during the coastal fisheries for maturing fish. This

would facilitate recovery of tags either in a specific
12 Acoustic and Archival Tags: Applications to Salmonid Research

fishery or hatchery.

 Studies that provide detailed information on

movements of salmonid using smart tags should obtain

or utilize concurrent data on ocean conditions so that

movements can be related to ocean currents, frontal

structure, temperature patterns, etc. Although smart

tags may monitor temperature, temperature fields

available over a broad area are needed to determine

habitat preference.

Specific Recommendations

 For ultrasonic tags, manufacture a size that can be

inserted into the stomach of smolts, 100-200 mm FL.

Increase the range of tags so they can be detected up to

1000 m. Study the feasibility of tracking smolts in the

coastal zone using a series of moored receivers that

either store data or relay data by radio to a shore station

or to satellite.

 For archival tags, we need tags that can be used on

or in maturing fish that monitor latitude, longitude, and

depth. External temperature or internal temperature

could also be monitored. Internal temperature may

increase, as it does in bluefin tuna, and provide

information on feeding periodicity and rates. Data from

archival tags could be recovered after capture of the fish

in a fishery, hatchery or homestream. However,

determination of the stock origin may be difficult for

fish caught at sea. Desirable features of archival tags

include sensors to measure compass heading and

swimming speed or tailbeat frequency so that currents in

the swimming field can be determined.

 Since mortality and predation are major ecological

concerns, and affect recovery of tags, sensors should be

developed to determine when and where a fish dies.

Monitoring tail beat or muscular contractions during

swimming, or changes in pH, have been suggested as a

way to obtain this information.

 For all types of tags, the accuracy of parameter

estimates and the effects of the tags on the behavior and

physiology of the fish should be carefully evaluated.

References

Hartt, A.C. and M.B. Dell. 1986. Early oceanic

migrations and growth of juvenile Pacific salmon and

steelhead trout. Int. North Pacific Fish. Comm. Bull.

46, 105p.

Pearcy, W.G. and J.P. Fisher. 1988. Migrations of

coho salmon, Oncorhynchus kisutch, during their first

summer in the ocean. Fish. Bull. 86:173-195.

Quinn, T.P. and B.A. terHart. 1987. Movements of

adult sockeye salmon (Oncorhynchus nerka) in British

Columbia coastal waters in relation to temperature and

salinity stratification: Ultrasonic telemetry results, p.

61-77. In H.D. Smith, L. Margolis, and C.C. Wood

(eds.) Sockeye salmon (Oncorhynchus nerka) population

biology and future management. Can. Spec. Publ. Fish.

Aquat. Sci. 96.

Weitkamp, L., P. Busby and K. Neely. 1996.

Latitudinal variations in life histories of salmonids.

Workshop on Marine and Ocean Survival of

Northeastern Pacific Salmon, unpubl. 
Acoustic and Archival Tags: Applications to Salmonid Research 13

Ocean Studies Using “Smart” & Hydroacoustic Tags

David Welch, High Seas Salmon Research, Ocean Sciences and Productivity Division, Pacific

Biological Station, Dept. of Fisheries and Oceans, Nanaimo, B.C. V9R 5K6

To date, open ocean salmon tagging has been

restricted to the use of uniquely numbered spaghetti or

disk tags. Tags are cheap, but application in the ocean

is expensive because of the need for an ocean-going

vessel capable of remaining out at sea for up to a

month. In the eastern north Pacific (Gulf of Alaska)

about 10% of all tags applied to salmon in the 1960s

were recovered. Even if the recovery position and date

is accurately recorded by the fisherman, then the

maximum information that can be obtained is the

straight line distance between the two points, and the

minimum swimming speed needed to transit directly

between the two points.

Tagging programs using the technology of the

1950s and 60s greatly improved our knowledge of the

relative distribution of different stocks and species in the

open ocean. However, these programs gave us only

glimpses of the environmental constraints that have

shaped the evolutionary biology of salmon and, by

implication, the environmental factors affecting their

productivity. I think that there are 3 prominent

applications for new tagging technology in the open 

ocean ecosystem:

(1) How do salmon navigate on the High Seas?

(2) How do salmon use the environment of the High

Seas?

(3) How are bioenergetics of salmon on the High Seas

determined?

Answers to these questions depend on knowing on

a day-by-day or even finer scale basis what salmon are

doing in the ocean, where they go, what environmental

conditions they avoid or are attracted to, and how

salmon migrate through frequently complex and

heterogeneous ocean conditions. In essence, we are

asking what evolutionary factors have shaped their

oceanic life histories. Smart tag technology is now

sufficiently accurate to allow us to address most of these

questions in the ocean. This talk detailed a short list of

questions I view as the next logical steps for us to

investigate, and discuss the next generation of tags on

which we should focus our development effort.
14 Acoustic and Archival Tags: Applications to Salmonid Research
Acoustic and Archival Tags: Applications to Salmonid Research 15

Experience Papers

The following paper and six abstracts describe selected studies pertinent to the

application of acoustic or data logging tags to salmonids. The first paper

describes a variety of studies with these tags that have been conducted in Japan,

the remainder in the U.S. or Canada. In the contributed abstracts, note that five

additional studies are described; two involve research on salmonids, three are on

other species.
16 Acoustic and Archival Tags: Applications to Salmonid Research

Acoustic and archival tagging work on salmonids in Japan

Miki Ogura, Tohoku National Fisheries Research Institute, 3-27-5, Shinhama-cho, Shiogama,

Miyagi 985, Japan

Abstract

I reviewed 12 acoustic and 5 archival tagging

studies on salmonids that have been conducted in Japan

since the 1970's. Acoustic tags have been used from

the mid 1970's for salmonid research and archival tags

were introduced to salmonid research in the 1990's. In

the 1970's and 1980's Japanese acoustic tagging

systems were used in Japan but from the 1980's the

VEMCO system became increasingly popular. Eight of

12 acoustic tagging studies were conducted in coastal

waters, three studies were done in offshore waters and

high seas, and one in a lake. In one of five archival tag

studies, fish were released from offshore waters, but

other works were conducted in coastal waters and rivers.

Chum salmon were used for most of Japanese studies

and recently masu salmon were also studied. The

purposes of the research using smart tags have been to

investigate fish behavior in relation to fishing gear and

to investigate salmon orientation and homing

mechanisms. The principal motivation, especially for

the early studies, was to learn how salmon move at sea.

To facilitate communication with North American

scientists, I put together a list of Japanese scientists

using smart tags for studying salmonids.

Introduction

Salmonids were frequently used as subjects during

the development of ultrasonic telemetry systems in

Japan because they are popular fish species, have

interesting behavior such as homing, and are easy to

handle for experiments. When considering the

application of archival tags, homing is a very good

characteristic because it facilitates recovery of the tag.

Though there were some preliminary studies conducted

in 1960's and early 1970's, in this report I reviewed

successful studies on salmonids with acoustic and

archival tags in Japan since the 1970’s. Some of the

most recent studies are not available on documents

and/or papers, and details of some of these studies could

not be presented in this report.

Acoustic and archival tagging systems

The National Research Institute of Far Seas

Fisheries (NRIFSF, formerly Far Seas Fishery Research

Laboratory) and Tokai University were pioneers in

developing ultrasonic telemetry in Japan. Their

telemetry system had been manufactured by Koden

Electronics Co., Ltd. (KODEN) since late 1970's

(Figure 1). Japanese studies in late 1970's and 1980's

were conducted by using this KODEN system.

KODEN may continue to make transmitters but the

receiver system has not been improved during the last

20 years. From the late 1980's, most Japanese research

groups began to use VEMCO products.

In many studies the transmitter was attached to the

base of the anal fin and allowed to trail from the fish

(Figure 2). In some recent studies, the transmitter was

attached on the back of the fish with two plastic

fasteners or vinyl strings (Figure 3). Stomach insertion

has seldom been used in Japan. The hydrophone was

attached at the bottom of a pole mounted at the side of

the research vessel. In most cases, the direction of

hydrophone was changed by hand rotation of the pole by

an operator, but recently a motor-driven pole was used

(Figure 4). Now one group has introduced a towed

hydrophone system from VEMCO but it has not been

used for tracking salmonids yet.

There are three study groups developing archival

tags for biological research; Kyoto University, National

Institute of Polar Research (NIPR), and NRIFSF (Fur

seal section). Archival tags have been developed for

large marine mammals since the 1970's (but not smart

memory tags, instead early versions used pen recorders).

In the 1990's, tags have been much miniaturized and

memory capacity has been increased, and the application

to fish study began. Tags developed by Kyoto

University are commercially sold through Alec

Electronics Co. Ltd. (Alec). NIPR's tags are also

available directly.
Acoustic and Archival Tags: Applications to Salmonid Research 17

Figure 1. KODEN receiver and transmitters.

The biggest concern of researchers using acoustic

tags is the accuracy of horizontal position. Telemetered

information, such as depth or temperature, is very

accurate (depending on the sensor and transmitter

system). Methods of positioning the research vessel

have greatly improved. In the past radar or Loran was

used but now GPS is used. However, the horizontal

position may have a large error. Archival tags would

also need to fix the horizontal position accurately.

Acoustic tagging studies

In 1974, NRIFSF and Tokai University conducted a

tracking study of maturing chum salmon at off Etorofu

Island, Kuril Islands (summary table A, 1; Ichihara et

al., 1975). This was apparently the first successful

tracking by Japanese scientists. They tracked the fish

over 163.6 km during 37 hours and presented the

horizontal tracks and vertical movement in their paper

(Figure 5). This shows many circular motions in the

fish tracks. In this study the fish's position (= research

vessel position) was determined by the radar observation

of the vessel and island, and the rotational trajectory was

not verified.

Ultrasonic telemetry was used in the environment

assessment for examining the effects of heated water

from an atomic power plant on fish behavior (Summary

table A, 2). Results of this kind of study were not

circulated widely, but Fukushima's report concluded that

they did not obtain enough data, especially on

horizontal movement, and they stopped using telemetry

in their assessment work.

One of the most interesting characteristics of

salmonids is their homing ability. Tokai University

scientists studied the effects of visual and olfactory

ablation on the swimming behavior of chum salmon
18 Acoustic and Archival Tags: Applications to Salmonid Research

Figure 2. External transmitter attachment: trailing from the fish. On the left is a fish with a pinger and on the

right a photo of a chum salmon with trailing type transmitter.

Figure 3. External transmitter attachment: fixed on the back.
Acoustic and Archival Tags: Applications to Salmonid Research 19

Figure 4. Hydrophone and pole rotating system.
20 Acoustic and Archival Tags: Applications to Salmonid Research

Figure 5. Horizontal movement of a chum

salmon (from Ichihara et al. 1975).

with acoustic tags (summary table A, 3; Yano and

Nakamura, 1992). Chum salmon caught in the river,

1.5 km upstream from the river mouth, were transported

to a release site at sea near the river mouth. Twentyone fish with acoustic tags were released as controls.

Vision was ablated in 6 fish, olfactory ablation was

done in 7 fish and both ablations were done in one fish.

Intact fish and blind fish returned to the home river, but

anosmic fish did not. From observations of the

horizontal and vertical movements for each experimental

group, the authors concluded that olfaction was

necessary for correct choice of the home river (as shown

in previous studies) and vision is important for

regulating the amplitude of vertical movements.

In 1980's some studies attempted to observe

salmon movement in coastal waters in relation to the

coastal fishing gears, such as the trap net (summary

table A, 4, 5, 6; Yoza et al., 1985; Soeda et al., 1987;

Ishida et al., 1988). It is important to know the

movements of adult salmon in coastal waters for

regulating these fisheries. The path of adult chum

salmon before entering the natal river was along the

coastline. Authors in Iwate PFES's group showed that

there was a relationship between salmon movement and

tidal direction. They were also concerned with the low

accuracy of horizontal position in this tracking method

(Figure 6).

Figure 6. Estimated existence area of chum

salmon in relation to the vessel. When the vessel

tracked chum salmon from A to B for the distance

shorter than 2 km, the moved area of chum salmon

are exhibited by the existence area of B less the

remaining area. (From Ishida et al. 1988).

In 1989, NRIFSF started a tracking study in the

open sea in the area of high seas salmon driftnet fishery

ground in order to examine the efficiency of surface

gillnets and to study migratory behavior (summary table

A, 7). After preliminary studies with tracking devices,

they decided to use the VEMCO system. They

continued this work during four years and tracked 23

individuals of 6 salmonid species in the central North

Pacific and the Bering Sea (Ogura and Arai, 1992;

Ogura and Ishida, 1992; Ogura 1994; Ogura and Ishida,

1995). The authors showed the vertical distribution of

each species and discussed the migratory ability of

salmonids in the open sea. 

Aomori PFES tracked masu salmon movements in

coastal waters in relation to the fishing gear (summary

table A, 8, 9, 12). Masu salmon have high

commercial value and Japan has had an enhancement

project for masu salmon for a long time. Aomori

PFES tracked masu salmon at three life history stages:

sea run juveniles in an estuary, immature fish in coastal

waters, and adult fish in coastal waters. Though the

tracking durations of juvenile fish were brief (from one

to six hours), and the number of immature and adult

fish tracked was also not enough, they provided general

descriptions of behavior. The author said that while

tracking fish in coastal waters he could not track fish

when they fish moved into shallow waters near rocks.

Aomori PFES subsequently changed from acoustic

tracking to archival tagging.

Hokkaido University and Hokkaido Salmon

Hatchery are continuing the tracking study to

investigate the mechanism of homing by using kokanee
Acoustic and Archival Tags: Applications to Salmonid Research 21

Figure 7. Tracks of four mature male kokanee salmon in Lake Toya during the spawning season. 

Arrowhead indicates the releasing point of each fish. A, control fish; B, magnetic cue-interfered fish; C,

visual cue-interfered fish; D, visual and magnetic cues-interfered fish. (from Ueda et al. 1995).

and masu salmon in Lake Toya (summary table A, 10;

Ueda et al., 1995; Sato et al., 1996). Lake Toya has

surface area 70 km2, average diameter 9.4 km and

average depth 116 m (Figure 7). Four mature fish were

subjected to one of the following treatments: A)

attachment of a brass ring on the head, B) attachment of

a NdFe magnet ring on the head, C) injection of a

mixture of carbon toner and corn oil into eyeball to

detach retinas, D) detached retinas and attachment of

magnetic ring. The results demonstrated the direct

return of kokanee using visual cues and indicated that

kokanee did not primarily use magnetic cues in the

selection of the natal area, but it is still likely that fish

supplementally use magnetic cues for their orientation.

They also conducted biochemical and cytophysiological

analyses as well as behavioral study with acoustic

tagging.

Chiba University and NRIFSF (and Tohoku

National Fisheries Research Institute) developed

artificial magnetic field generators consisting of an

electromagnetic coil and a drive circuit to investigate the

magnetic sense of the ocean migrating maturing

salmonids (Figure 8; Yano et al., 1996). In the first

several hours, this device was off and the salmon swam

under the normal geomagnetic field. Then the magnetic

field generator began inducing an alternating magnetic

field whose intensity is 6 gauss, with polarity reversed

every 11.25 min. during the subsequent 16 hours. This

device was used in the field research in 1994 off Kuril

Island and 1995 off Hokkaido’s Pacific coast. Changes

of fish behavior were observed by the acoustic telemetry

system (summary table A, 11; Yano et al., 1995; Yano

et al., 1996). In 1994, tracking time was not sufficient

to evaluate the difference between behavior under

artificial magnetic field and normal conditions.

However, one fish with this device returned to a

Hokkaido river 20 days after it was released. In 1995, 4

chum salmon were tracked during 67 hours. Most fish

showed no remarkable changes of movements after

application of the altered magnetic field.

Archival tagging works

To investigate the behavior of maturing chum

salmon returning vicinity of their natal river in early

stage for spawning (i.e. water temperature in the coastal

waters is still high), Iwate PFES released 10 chum

salmon attached with two archival tags (temperature and

depth) for each fish (summary table B, 13). Seven fish

were recaptured by trap nets in the coastal waters. The

data showed that the fish swam in water temperatures 
22 Acoustic and Archival Tags: Applications to Salmonid Research

Figure 8. Artificial magnetic field generator

attached to a chum salmon.

less than 13 ̊C at depths of 100-210 m in daytime and

occasionally ascended to the surface where water

temperatures was more than 18 ̊C at night. To further

investigate how salmon select their ambient

temperature, NIPR and Iwate PFES released 27 chum

salmon with archival tags (both temperature and depth

recording) and obtained 12 recoveries (summary table B,

17) in 1995 (Tanaka et al., 1996). This research was

conducted in October and December, two different water

temperature conditions. Results showed that salmon

stayed in deep water in October (salmon avoided high

temperatures and took refuge in deeper water) whereas

they stayed in shallow water and rarely occurred in

deeper water in December.

NRIFSF released 13 chum salmon with depth

recording archival tags from off Kuril Islands under the

usual tagging program (summary table B, 14). One

fish was recovered in the coast of Hokkaido and 21 days

data showed clear daily vertical movement pattern

(Figure 9).

As mentioned before, Aomori PFES started the

archival tagging for masu salmon instead of the acoustic

tagging from 1995 (summary table B, 15). They

released 5 adult masu salmon but no recovery was

reported in 1995.

Figure 9a. Vertical movement of chum salmon from September 6 to 28, 1994. 

Shaded time zones indicate nighttime.
Acoustic and Archival Tags: Applications to Salmonid Research 23

Figure 9b. Average vertical movement of chum salmon. The average depth during 1

hour periods. Values are means and standard deviations. JST, Japan Standard Time.

Kyoto University scientists have investigated the

otolith microchemistry to detect the timing of ocean

entry and upstream movement of masu salmon. They

began the behavioral study using archival tags this year

(summary table B, 16). The purpose of this archival 

tagging was to learn the duration and the timing of

residence in the river mouth and to compare this

information with the archival information on the

otolith. Next year, researchers are planning to track

masu salmon in the river so radio or satellite tracking

will be used.

Summary figure. Locations of smart tag studies on salmonids by Japanese scientists. The

numerals indicate study numbers in summary tables A and B ( located on the following two pages).
24 Acoustic and Archival Tags: Applicatio

Summary table A. Studies with acoustic tags conducted since the 1970's in Japan. Numbers in the left column refer to studies in the text 

the summary figure on page 23.

Organization Period Area System manufacture Species Number tracked Total data (hr) Purpose of research, 

1 NRIFSF 1974 Off Kuril Island Original Chum 1 37 Swimming 2 Fukushima PFES 1978-1979 Coastal waters Honshu Pacific Coast KODEN Chum 6 50 Assessment research 

plan

3 Tokai Univ. 1979-1981 Coastal waters Hokkaido Okhotsk Sea KODEN Chum 35 394.5 Natal river findin

Visual and /or olf

4 Nihon Univ. 1982-1996+ Coastal waters, Hokkaido Okhotsk Sea KODEN Chum 20+ 422+ Swimming behavior 

in relation to coas

5 Aomori PFES 1983 Coastal waters, Tsugaru Strait KODEN Chum 5 ? ?6 Iwate PFES 1984-1985 Coastal waters, Honshu Pacific Coast KODEN Chum 6 81 Swimming behavior 

in relation to coas

7 NRIFSF 1989-1992 High seas, Bering sea and central N. Pacific VEMCO 6 Salmon Species 23 1138 Migratory 8 Aomori PFES 1992-1993 Coastal waters, Honshu Japan sea coast VEMCO juv. Masu Salmon 7 27 Estuary habitat of 9 Aomori PFES 1992-1993 Coastal waters, Honshu Japan sea coast VEMCO Masu salmon 3 79 Swimming behavior 

in relation to coas

1 0

HSH,

Hokkaido

Univ.

1993-1996+ Toya lake VEMCO

Kokanee

Masu

salmon

13 ? Natal river finding m

ablation, magne

1 1 Chiba Univ., NRIFSF 1994-1995 Off Kuril Island, Off Hokkaido VEMCO Chum Homing behavior, A

fiel

1 2 Aomori PFES 1995 Coastal waters, Honshu Pacific coast VEMCO Masu salmon 4 ? Swimming behavior 

in relation to coas

NRIFSF: National Research Institute of Far Seas Fisheries. KODEN: Koden Electronics Co., Ltd., Shinagawa, Tokyo, JapanPFES: Prefectural Fishery Experimental Station. HSH: Hokkaido Salmon Hatchery
Acoustic and Archival Tags: Applications to Salmonid Research 

Summary table B. Studies with smart tags on salmon in Japan. Numbers in the left column refer to studies in the text and locations on thon page 23.

Organization Period Area System

manufacture

Species Number of fish

recaptured/released

Days of data Purpose of 

tr

1 3 Iwate PFES 1993 Coastal waters, Honshu Pacific Alec Chum 7/10 Swimmi

relation to 

1 4 NRIFSF 1994 Off Kuril Island Alec Chum 1/13 23 Swimm1 5 Aomori PFES 1995 Coastal waters, Honshu Japan sea VEMCO Masu salmon -/5 - Swimmi

coastal wa

coastal 

1 6 NIPR, Iwate PFES 1995 Coastal waters, Honshu Pacific Original Chum 12/27 >10 per individual Swimmi

relation to 

1 7 Kyoto Univ., Toyama PFES 1996+ River and estuary, Honshu Japan Sea coast Alec Masu salmon ? ? Behavio

NIPR: National Institute of Polar Research Alec : ALEC Electronics Co.,Ltd., Nishi-ku, Kobe, Japan
26 Acoustic and Archival Tags: Applications to Salmonid Research

Salmonid researchers working with smart tags in Japan

_____________________________________________________________________________________________

Masahide Kaeriyama

Research Division, Hokkaido Salmon Hatchery

2-2 Nakanoshima, Toyohira-ku, Sapporo 062, Japan

Tel: 011-822-2131, Fax: 011-823-8979

kiyama@salmon.affrc.go.jp

Kingo Ito

Aomori Prefectural Fishery Experimental Station

439-5, Aza-Oowada, Ooaza-Akaishi, Ajigasawa-cho,

Nishitugaru-gun, Aomori 038-27, Japan

Tel: 01737-2-2172, Fax: 01737-2-2778

Hiroshi Ueda

Director, Toya Lake Station for Environmental 

Biology, Hokkaido University

122 Tsukiura, Abuta-cho, Abuta-gun, 

Hokkaido 049-57, Japan

Tel: 0142-75-2651, Fax: 0142-75-2943

Yasuhiko Naito

Professor, National Institute of Polar Research

9-10, Kaga, 1-chome, Itabashi-ku, 

Tokyo 173, Japan

Tel: 03-3962-4761, Fax: 03-3962-5743

naito@nipr.ac.jp

Takahito Kojima

Faculty of Nihon University

1866 Kameino, Fujisawa

Kanagawa 252, Japan

Tel: 0426-81-6241, Fax: 0426-82-1819

Yo Sakaki & Akira Yano

Faculty of engineering, Chiba University

1-33 Yayoi-cho, Inage-ku

Chiba 263, Japan

Tel: 043-290-3341, Fax: 043-290-3039

salmon@cuphd.nd.chiba-u.ac.jp (Akira Yano)

Akihiko Kasai

Faculty of Agriculture, Kyoto University

Kitashirakawa, Sakyo-ku

Kyoto 606-01, Japan

Tel: 075-753-6216, Fax: 075-753-6468

kasai@kais.kyoto-u.ac.jp

Yukimasa Ishida

National Research Institute of Far Seas Fisheries

5-7-1, Orido, Shimizu

Shizuoka 424, Japan

Tel: 0543-36-6034, Fax: 0543-35-9642

ishiday@enyo.affrc.go.jp

_____________________________________________________________________________________________

References

Ichihara, T., T. Yonemori, and H. Asai. 1975.

Swimming behavior of a chum salmon, Oncorhynchus

keta, on the southern migration off Etorofu Island, the

southern Kuril Islands. Bull. Far Seas Fish. Res. Lab.,

13: 63-77.

Ishida, K., S. Nagahora, Y. Inoue, and T. Watanabe.

1988. Behavior of adult chum salmon Oncorhynchus

keta, homing to the coast of Sanriku. Nippon Suisan

Gakkaishi. 54(8): 1279-1287.

Ogura, M. and N. Arai. 1992. Outline of biotelemetry

study by the Shin-Riasu maru, 1992. p. 81-88. In

Reports on the research of salmon resources in the

North Pacific Ocean in 1992, Salmon Report Series 36,

Nat. Res. Inst. Far Seas Fish., Shimizu, Shizuoka, 424

Japan.

Ogura, M. and Y. Ishida. 1992. Swimming behavior

of coho salmon, Oncorhynchus kisutch, in the open sea

as determined by ultrasonic telemetry. Can. J. Fish.

Aquat. Sci. 49: 453-457.

Ogura, M. 1994. Migratory behavior of Pacific

salmon (Oncorhynchus spp.) in the open sea. Bull.

Natl. Res. Inst. Far Seas Fish. 31. 1-139. (in Japanese

with English summary).

Ogura, M. and Y. Ishida. 1995. Homing behavior and

vertical movements of four species of Pacific salmon

(Oncorhynchus spp.) in the central Bering sea. Can. J.

Fish. Aquat. Sci. 52. 532-540.
Acoustic and Archival Tags: Applications to Salmonid Research 27

Sato, A., T. Yamamoto, T. Kitahashi, A. Urano, M.

Kaeriyama, H. Ueda, and K. Yamauchi. 1996.

Comparison of homing behavior between lacustrine

sockeye and masu salmon in lake Toya. Proceedings of

the 3rd international symposium on fish endocrinology

satellite international symposium on fish migration.

Lake Toya, Hokkaido, Japan. p. 79.

Soeda, H., Yoza, K., and Shimamura, T. 1987. On

the swimming behaviour of chum salmon in early

migratory season off the coast of Hokkaido, Okhotsk

Sea. Nippon Suisan Gakkaishi, 53: 1827-1833.

Tanaka, H., Y. Takagi, Y. Yokosawa, and Y. Naito.

1996. Swim behavior of homing chum salmon

determined by micro data tag. In abstracts of JapanGLOBEC symposium: Development and application of

new technologies for measurement and modeling in

marine ecosystems. 27-28 June 1996 Nemuro, Japan.

Ueda, H., M. Kaeriyama, A. Urano, K. Kurihara, and

K. Yamauchi. 1995. Homing mechanisms in salmon:

Roles of vision and olfaction. Proceedings of the fifth

international symposium on the reproductive

physiology of fish, University of Texas at Austin,

Texas, U.S.A., 218-220.

Yano, A., A. Sato, and Y. Sakaki. 1995. Study of

chum salmon, Oncorhynchus keta, movement in a

disturbed magnetic field in the North Pacific ocean

using ultrasonic telemetry. Salmon Report Series,

Natl. Res. Inst. Far Seas Fish. 39. 174-188.

Yano, A., M. Ogura, A. Sato, Y. Sakaki, M. Ban, and

K. Nagasawa. 1996. Ultrasonic telemetry for

investigating the magnetic compass orientation of

maturing chum salmon, Oncorhynchus keta, migrating

off the coast of Kushiro. Jap. Soc.Elec. MAG-96-21.

75-82.

Yano, A., M. Ogura, A. Sato, Y. Sakaki, M. Ban, and

K. Nagasawa. 1996. Development of ultrasonic

telemetry technique for investigating the magnetic sense

of salmonids. Fisheries Science. 65:698-704.

Yano, K. and Nakamura, A. 1992. Observations on

the effect of visual and olfactory ablation on the

swimming behaviour of maturing adult chum salmon,

Oncorhynchus keta. Japan. J. Ichthyol., 39: 67-83.

Yoza, K., Soeda, H., Shimamura, T., Hasegawa, E.,

and Yoshihara, K. 1985. On the horizontal swimming

behaviour of Chum salmon in early migratory season

off the coast of Shiretoko peninsula. Nippon Suisan

Gakkaishi, 51: 1419-1423. (in Japanese with English

summary).
28 Acoustic and Archival Tags: Applications to Salmonid Research

Atlantic Salmon Data Requirements and Data-Logging Tags

Kevin Friedland, NMFS, 166 Water St., Woods Hole, MA, 02543, USA

The distribution of thermal habitat has emerged as

an important correlate to survivorship and sexual

maturation processes in Atlantic salmon. The first year

of ocean life is critical to defining population abundance

and fishery yields of Atlantic salmon populations. As is

the case with other salmonids, the ecology of Atlantic

salmon during the first year at sea is poorly understood

due to a lack of basic data on distribution and behavior.

Research catches have yielded some information; but,

research cruise effort has been limited and salmon

post-smolts have proven difficult to catch in

conventional gears. Some success has been achieved

recently using small mesh gill nets in the Labrador Sea

and surface trawls in the Norwegian Sea; however, a

comprehensive description of the thermal preferences

and distribution of post-smolts is still lacking. Index 

stocks in the northeast Atlantic area survive at higher

rates when warm waters dominate the North Sea and

Norwegian coast during May, the peak smolt migration

month. These temperature trends may affect post-smolt

growth directly or affect post-smolt migrations.

Population abundance of both North American and

European two seawinter salmon has been correlated with

over-wintering thermal habitat. It has been suggested

these temperature distributions guide migrations, which

in turn influence sexual maturation. Data-logging tags

offer a tools to study both survival and maturation

phenomena in Atlantic salmon. Tags are already being

applied to adult salmon to study thermal preferences of

maturing fish; however, no tags are yet available to

record thermal history of post-smolts during the critical

first year at sea. 

_____________________________________________________________________________________________

Ultrasonic Tracking of Salmonids: Selected Experiences and Perspectives

Thomas Quinn, University Of Washington, Fisheries Research Institute, WH-10, Seattle, WA

98195

The movements of salmonids in marine waters are

of great interest to those studying migratory behavior

and to those charged with managing fisheries and

conserving fish populations. Fisheries take advantage

of migratory patterns, so knowledge of these patterns is

essential for sound management. In pursuit of basic

knowledge with applications to management, I have 

been involved in several studies using ultrasonic

telemetry. I will briefly review the work on sockeye

salmon, steelhead trout and chinook salmon, indicating

some of the patterns observed. I will also discuss the

drawbacks of "conventional" tracking and present two

situations that present excellent opportunities to test

archival tags. 
Acoustic and Archival Tags: Applications to Salmonid Research 29

New Technologies for Measuring Tag Induced Stress: 

Determining Competency Over Time 

Paul Siri, Bodega Marine Laboratory, Univ. Of California, Davis P.O. Box 247, Bodega, CA 

94923

The desirability to create increasingly powerful,

intelligent tags that provide insight to stock behavior is

tempered by physiological limitations created by host

response. Although large and sophisticated tags have

been tested successfully in elasmobranchs and large

bony fish such as marlin, swordfish and tuna, the

ability to tag salmon with smart tags will require

evolution to smaller packages and a thorough

understanding of host response as measured by

conventional cortisone and glucose techniques and newer 

more sophisticated cellular and molecular assays that are

proving to be more reliable and sensitive indicators of

stress events. Together, these tools will provide insight

to cumulative stress factors that will assist in

interpreting the range of environmental conditions that

make anadromous fish such a challenge to tag. The

ability to sort out multiple stress events will guide the

determination of reliable tag size limit and the

appropriate tagging environment. 

_____________________________________________________________________________________________

NerkaSim: A micro-computer model of the Northeast Pacific Ocean and 

Bering Sea for simulating sockeye salmon migrations and growth.

Michael Healey, Fisheries Centre, Westwater Research Centre, Department of Earth and Ocean

Sciences, University of British Columbia, Vancouver, BC, Canada.

A spatially explicit, individual-based migration

model of the Northeast Pacific Ocean and Bering Sea

(NerkaSim) has been constructed to explore hypotheses

regarding migration and growth of sockeye salmon.

Monthly surface currents (from an empirical model), sea

surface temperatures (from COADS data), and prey

fields (from available zooplankton data) provide the

space-time variability of the biophysical environment

from 1950 to the present. Plausible migration

behaviours have been parameterized. Fish movement

may be random or directed, and swim speed may be

proportional to body length or optimum cruising speed

(a function of fish weight and temperature).

Bioenergetics equations are used to model growth (a

function of fish weight, temperature, swim speed, and

available food). The model runs under Windows95 or

WindowsNT and provides a variety of graphical and

statistical outputs.

 NerkaSim was used to formalize, test and explore

alternatives to an accepted yet untested conceptual model

of sockeye migration (French et al. 1976), which has

fish migrating twice around the Alaska Gyre during

their two-year period of ocean residence. Using minimal

assumptions about navigational capability and

swimming behaviour, model fish only completed one

loop of the gyre; however, these results account just as

well for the available empirical data as the "accepted"

model. Our most striking result was the degree to which

interannual variations in surface currents of the Gulf of

Alaska influenced the migration trajectories. These

simulations have suggested several hypotheses that

could be validated by archival tagging (one versus two

loops of the gyre, large differences in migration

trajectories between years driven by current variations,

greatly different oceanic locations of year classes just

prior to return migration).

 The flexibility of NerkaSim allows the testing of a

very broad range of hypotheses about sockeye migration

behaviour and salmon growth. Because sockeye salmon

disperse over large areas in the open ocean, the spatial

and temporal heterogeneity of the environment

experienced by members of the same population can be

captured well using this individual-based modelling

approach. Prior to undertaking any costly, large-scale

archival tagging program, NerkaSim should be

considered for developing and refining testable

hypotheses. It should also be considered for the

quantitative analysis of salmon trajectories obtained

from tagging experiments, particularly when the effects

of advection and salmon behaviour shouldn’t be

separated.
30 Acoustic and Archival Tags: Applications to Salmonid Research

Computer Simulations of Sockeye Salmon Return Migrations: Results yielding

testable hypotheses of migration behaviour and the effects of the marine

environment on migration paths that plead for archival tagging experiments.

Keith A. Thomson, Fisheries Centre and Department of Earth and Ocean Sciences, University of

British Columbia, Vancouver, BC, Canada.

Latitude of landfall, coastal migration routes, and

timing of sockeye salmon during their return migration

are important to Canadian and U.S. fisheries managers,

particularly, the latitude of landfall and coastal

migration routes of Fraser, Nass and Skeena River

sockeye because the year- to-year variation in migration

paths affects the proportion of fish accessible to

American fishermen. We have used computer models to

simulate the effects of gyre-scale and mesoscale currents

on sockeye salmon migrations, gaining new insights on

how sockeye navigate and how interannual changes in

the ocean may affect the return migration paths. The

results have been used to develop new indices of ocean

variability for predicting stock-specific return times of

Fraser River sockeye; however, lingers doubts about the

robustness of such forecasts will persist until we obtain

a move complete understanding of the underlying

processes. The available empirical data are insufficient

to verify our migration models - archival tagging

experiments are called for.

 Simulations of the effects of gyre-scale currents on

sockeye return migrations have shown that the

interannual variability of northeast Pacific Ocean

currents could account for year-to-year differences in

return times as high as 2 wk and latitudes of landfall as

high as 550 km. The eastward-flowing Subarctic

Current assists the homeward migration of sockeye and

the northward-flowing Alaska Current deflects migrating

fish to the north. A stronger Alaska Gyre circulation

would generally result in earlier return times and more

northward latitudes of landfall, depending on the premigration distribution of the fish. Simulations of the 

effects of the Sitka eddy on sockeye returning to

northern British Columbia were prompted by

speculation that this vigorous mesoscale eddy, which is

not present every year, would deflect migrating salmon

to the south (thereby affecting the proportion of salmon

accessible to Alaskan fishermen). Migration paths were

simulated using a range of hypothesized directionfinding mechanisms (i.e. compass orientation,

navigation with constant swimming speed, and speedcompensated navigation) and rheotactic responses to

ambient surface currents. The least complex migration

behaviour (i.e. compass orientation with no rheotaxis)

was only slightly less efficient in metabolic terms than

the dynamic programming solution (which calculated

the optimum migration paths by minimizing metabolic

cost). It appears that a complex migration behaviour

need not be postulated for efficient return migrations.

Except for behaviours with positive rheotaxis, the eddy

currents provided a homeward "boost" to model fish and

reduced migration times. The eddy also effected

bifurcations of migration paths around its centre and

bimodal distributions of salmon return times at the

coast. The Sitka eddy does appear to effect southward

deflections of migration paths, and thus more southward

latitudes of landfall compared to when the eddy is not

present. The largest year-to-year differences in latitudes

of landfall, however, were due to interannual variations

in the Alaska Current, not the presence or absence of

the Sitka eddy.

 These results comprise a set of testable hypotheses

which should be considered for study with archival

tagging experiments.
Acoustic and Archival Tags: Applications to Salmonid Research 31

Auke Bay Laboratory’s Ocean Carrying Capacity Research Program

John H. Helle, Auke Bay Laboratory, Alaska Fisheries Science Center, National Marine Fisheries

Service, Juneau, Alaska

A major marine climate regime shift occurred in the

North Pacific Ocean during 1976-77. Survival of

salmon at sea increased greatly after this shift.

However, body size of chum salmon decreased and ageat-maturity increased in both North America and Asia.

Most of the other species of Pacific salmon have also

decreased in size. These changes have coincided with

record numbers of salmon returning to spawn, which

may indicate that the ocean carrying capacity for

salmonids may be limited under certain conditions. 

The North Pacific Anadromous Fish Commission

(NPAFC) at their 1993 annual meeting identified two

critical issues for research by the member parties: 1)

factors affecting current trends in ocean productivity in

the North Pacific Ocean and their impacts on salmonid

carrying capacity, and 2) factors affecting changes in

biological characteristics (growth, size and age at

maturity, oceanic distribution, survival, and abundance)

of Pacific salmon. 

The Ocean Carrying Capacity Research Program 

(OCC) was initiated in 1995 at the Auke Bay

Laboratory to respond to these concerns. This Program

has four components: 1) research on juvenile salmon in

coastal waters, 2) research on immature and maturing

salmon in coastal and offshore waters, 3) monitoring of

oceanographic conditions along the coastal waters, and

4) retrospective research on growth using scales,

otoliths et al. 

Various aspects of this research were described, in

particular, the successful 42 day cruise of the chartered

FV Great Pacific during July and August 1996. A

surface trawl was towed at 5 knots and proved very

effective in capturing juvenile and immature salmon.

This gear was fished from shore to the continental shelf

from Dixon Entrance to beyond Amchitka Island in the

Aleutian chain. More than 9000 juvenile and immature

salmon were captured and samples were retained for

genetic stock identification, examination of heatmarked otoliths, and research on growth, energetics, and

food studies. 
32 Acoustic and Archival Tags: Applications to Salmonid Research
Acoustic and Archival Tags: Applications to Salmonid Research 33

Technology Papers

The following six abstracts describe selected studies on current acoustic or data

logging tag technology and evaluation. Two abstracts represent evaluation or

benchmark studies of tag accuracy and the need for further evaluation, one the

current development of a data logging tag, and the remaining three describe

products from different manufacturers. In the contributed abstracts, note that

products from four additional manufacturers are described.
34 Acoustic and Archival Tags: Applications to Salmonid Research

Benchmark Tests of Accuracy of Two Archival Tags

A. Peter Klimley, Bodega Marine Laboratory, Univ. of Calif., Davis, P.O. Box 247, Bodega

Bay, CA 94923 

Charles Holloway, Joint Institute of Marine and Atmospheric Research, University of Hawaii,

1000 Pope Rd., Honolulu, HI 96822 

Geolocating archival tags obtain records of the daily

geographic positions of tagged fish. Longitude is

determined using a method similar to that used by

ancient sailors to navigate the oceans. They found their

longitude from the difference between the time when the

sun was at its highest point at their present location and

the expected time at a reference location (e.g.,

Greenwhich, England). This time differential was

measured with a chronometer. The archival tag has an

accurate internal clock which can be initialized to GMT.

However, the tag can not find noon directly from the

position of the sun, but does so indirectly by sensing

the rapid changes in the level of light under water when

the sun rises and sets below the horizon each day.

Apparent noon can be estimated as midway between

points on a curve of daytime light curve. Daylength is

additionally an indicator of latitude. The accuracy of the

latitudinal coordinate is dependent both on latitude

(highest near the poles, lowest near the equator) and

time of year (highest during the solstices, lowest during

the equinoxes). 

We tested the accuracy of two archival tags

(Northwest Marine Technology [NMT], Wildlife

Computers [WC]) at a depth of 10 m on a Fish

Aggregation Device (FAD) located 9 km northwest of

Oahu, Hawaii (21o 27.50' N., 158o 16.90' W). The

mean longitude determined over a period of 26 days by

the NMT tag was 16.6 km west of the FAD and the

coordinate varied ±57.0 km along a meridian. The

mean longitude of the WC tag varied from 8.5 km east

to 75.8 km west of the FAD based upon the sampling

interval (2, 4, and 6 min). These positions varied

±46.7-88.1 km. The mean latitude of the WC tag over

15 days ranged from 16.8 km north to 41.7 km south of

the FAD with positions varying ±133.4-183.4 km. We

will briefly describe tests on a prototype magnetic field

sensor capable of increasing the accuracy of the tag's

latitude coordinate. This sensor would estimate latitude

using (1) an estimate of the tag's longitude based upon

light changes, (2) a measurement of local total field

intensity, (3) a file of known intensities for the same

longitude corresponding to different latitudes, and (4) the

one-dimensional root- finding Newton-Raphson method. 

_____________________________________________________________________________________________

Progress on Geoposition Estimation and Assessing Archival Tag Accuracy

David Welch, High Seas Salmon Research, Ocean Sciences and Productivity Division, Pacific

Biological Station, Dept. of Fisheries and Oceans, Nanaimo, B.C. V9R 5K6

We began evaluating the capabilities of archival

tags for use in ocean studies of salmon migration and

bioenergetics starting last fall (1995). This experience

has led me over a circuitous course. The first major

message I have is that designing a proper experiment

to calibrate and evaluate geoposition of any potential

tag is far from trivial. As a result, the preformance of

most tags on the market have not been sufficiently

“ground-truthed”, simply because it is extremely

difficult to do so. As a result, the true capabilities of

most tags on the market are unknown, and the practical

benefits of various technical differences touted by the

manufacturers is impossible to evaluate. The bottom

line is that independent evaluation of the capability of

various tags after the tags are commercially available is

crucial, and must be built into the costs of conducting a

tagging program. It is unacceptable in my view

to rely on manufacturer’s stated claims of

accuracy before a very serious effort is put

into validating accuracy. This is the

responsibility of the scientific community.

The second (and primary) message of this

presentation is that archival tags show great promise for

opening up major avenues of research which to date

have been blocked by the lack of appropriate
Acoustic and Archival Tags: Applications to Salmonid Research 35

technology. In my own research, I have focussed on

developing a modified strategy for estimating

geoposition from dawn and dusk, and developed

specialized filters that can be designed to pass the

geoposition signal while excluding much of the

variability due to electronic noise, variations in sea

state, cloud cover, and fish orientation. The latter are

very substantial! I believe these technical advances will

allow us to significantly improve the estimation of

daily geoposition from light data over what was

previously possible, and perhaps allow us to estimate

the daily mean position of a tagged animal to within 

perhaps ±20 kms-- much closer than was previously

possible. More importantly, the positional accuracy is

likely now as small or smaller than the amount of

movement a tagged salmon might make each day, and

below the spatial resolution of physical oceanographic

models of the current and temperature fields in the

ocean. My second message is that the time is

now ripe for starting a major ocean tagging

program. By its nature, this means that the

program should be a single focussed

international effort, including all of the

Pacific Rim salmon producing countries.

_____________________________________________________________________________________________

Development of a Small Format Temperature Logging Tag

Kevin Friedland, NMFS, 166 Water St., Woods Hole, MA, 02543, USA

The Northeast Fisheries Center, in cooperation

with researchers at the University of Rhode Island and

private sector industry, is developing a data-logging tag

that can be applied to small fish. The approach has been

to concentrate on one measured parameter, temperature,

and package the tag as small and cost effectively as

possible. To achieve this design goal, the tag will be

based on a monolithic integrated circuit that performs

all the functions of a programmable temperate

data-logger. The thermal sensor is implemented as a

simple pn-junction. Pn-junction voltages will be

converted to digital data with an 8-bit A/D converter,

which will more than exceed accuracy goals of 0.5 ̊C.

Timing will be kept onboard the chip by using a ring 

oscillator circuit, thus, eliminating the need for an

external crystal oscillator and reducing fabrication and

engineering costs. However, this design feature is not

without its limitations, timing accuracy is

compromised and power consumption is accelerated

reducing the longevity of the tag. Serial communication

on the device will allow delayed arming and flexible

programming of sampling intervals. The feasibility of

bonding the chip directly to a battery power supply

housing is being investigated. This tag system provides

the basis to develop a family of data logging tags

utilizing the space and cost advantages of silicon

integrated circuits.

_____________________________________________________________________________________________

Tagging Technology from VEMCO Limited

Fred Voegeli,VEMCO Limited,100 Osprey Drive, Shad Bay, NOVA SCOTIA B3T 2C1, Canada. 

Ultrasonic tracking techniques are fast changing to

allow a wide range of automated data gathering

experiments with fish released after tagging with

electronic tags. The increased pace of developments has

been enabled by the availability of miniature low power

microprocessors to perform data gathering and

communication functions.

The archival or storage tag can gather a Megabyte

or more of data but requires that the animal be

recaptured to retreive the data. To retreive the data

without recapture of the fish we combine data storage

with ultrasonic data communication. The first

implementation of a "Communicating Histogram

Acoustic Transponder" (CHAT) tag was tested this

summer in a package size suitable for sea mammals and

sharks. The tag size although excessive for salmon

(32mm Diameter x 120mm Length) can be miniaturized

in the future for work on adult salmon. The limitation

placed on the amount of data which can be transmitted

in the low acoustic bandwidth (typically 6000 readings)

demands that some data processing be done on the tag to
36 Acoustic and Archival Tags: Applications to Salmonid Research

reduce the amount of data. Data reduction algorithms

can be designed for a particular animal type or study.

The prototype system provides a user selectable interval

over which Min, Max and Average depths are recorded

along with temperatures at each depth.

 Ultrasonic receiver and tracking system

developments have also been evolving rapidly. The

receiving system for the CHAT tag is suitable for large

vessel tracking at sea with four hydrophone arrays and a

personal computer interface which points the helmsman

directly to the tag showing range and bearing. This

allows the tracking vessel to maintain contact with a

tag until the data has been downloaded. Automated

monitoring stations for simple identification tags will

be modified to gather data from CHAT tags. The data

gathering system which will be described allows the tag

to break off communication at any point and resume

communication at the same or any other monitor. 

We have also put significant effort into tag

development for salmon smolt studies. In the last two

years we have been involved in a collaboration between

the Atlantic Salmon Federation and Fisheries and

Oceans Canada to develop a tag which will allow

tracking of wild smolt as they move out of the rivers. A

new single chip crystal controlled transmitter has been

successfully implanted in wild smolt of 150mm length.

The transmitter size is 8mm diameter by 26mm length

and gives up to 400 meters range in salt water for one

month. Smaller tags with longer life can be built with

the same single chip circuit if detection range can be

sacrificed. 

Automated detection sites have proved valuable for

monitoring the passage of smolts out of an estuary.

Submersible monitors can identify multiple tags on

each frequency. A description of plans for further

development of automated receivers and miniature

ultrasonic tags will be presented at the workshop.

_____________________________________________________________________________________________

Archival Tag Technology from Northwest Marine Technology, Inc.

Phil Ekstrom, Northwest Marine Technology, Inc., P.O. Box 427, Shaw Island, WA 98286

The NMT archival tag was developed for

geolocation in tuna, and has demonstrated longitude

accuracy of better than one degree in that service. Errors

appear to be dominantly random and unbiased, and an

average over a long run of successive positions is

ordinarily good to a few tenths degree. Its latitude

accuracy from solar data is less good, with systematic

errors of perhaps two degrees at mid-latitudes, plus

random errors, but that is expected to improve.

Latitude may also be obtained from sea temperature, but

its accuracy difficult to evaluate. The tag can return

daily positions for a mission of at least seven years.

Time series logging of internal and external

temperature, depth, and light intensity is also provided

for a more limited duration. Size is 16 mm diameter by

100 mm long, weight 52 grams. Surface materials are

stainless steel, silicone, and fluorocarbon plastic. The

tag is designed to be implanted, with a 2mm diameter

measurement stalk protruding through the skin of the

animal. Tuna tolerate it well, showing none of the

irritation or infection common with other percutaneous

tags at the site of skin penetration. Implantation in

salmon has not been tried.

A new version now under development will be

smaller and lighter with larger memory and longer life.

A possible version of the tag adapted specifically to the

shorter life span of salmon could be smaller and lighter

yet. 
Acoustic and Archival Tags: Applications to Salmonid Research 37

Lotek Marine Technologies Inc.--Salmonid Acoustic and Archival Tags; 

Current Products and Emerging Technologies

Keith Stoodley. Lotek Marine Technologies, Inc., 114 Cabot Street, St. John's, NF, A1C 1Z8 

Canada

Lotek Marine Technologies is a full service

biotelemetry company which specializes in the design,

manufacturing and servicing of innovative products and

systems for tracking and monitoring in the ocean

environment.

Lotek Marine builds upon nearly two decades of aquatic

telemetry expertise at its sister company, Lotek

Engineering; including its role in a multi-agency effort

to examine factors influencing the migration of

Chinook (Oncorhynchus tshawytscha) and stealhead (O.

mykiss) on the Columbia and Snake rivers. Lotek’s

acoustic expertise and product line was enhanced by the

recent signing of a licensing agreement with the

Ministry of Agriculture, Fisheries and Food (MAFF) of

the United Kingdom. For the past 30 years, MAFF’s

Directorate of Fisheries Research, has provided

innovative and reliable telemetry systems for

application to environmental issues in the estuarine and

marine environment. Yet another significant Lotek

collaboration, is its five year partnership with the

Institute of Biotelemetry at the University of Waterloo

and the Natural Sciences and Engineering Research

Council (NSERC). In recognition of the need for

improved tools and technologies to understand and

predict the behavior and response of fish to natural and

anthropogenic perturbations, this initiative includes

studies ranging from fundamental muscle physiology to

studies of fish energetics, nutrition and condition

indices.

Recent developments have brought microprocessor

based transmitters to the forefront. Our ‘field-proven’

digitally encoded telemetry system dramatically

improves your ability to keep track of large numbers of

tagged fish. The ability to tag multiple fish on the

same frequency optimizes the use of available

bandwidth, decreases scan time and hence decreases the

probability of missing fish while increasing the tags

operational life. Lotek Marine also supply a variety of

non-coded specialty transmitters for use of micropingers

 on small fish such as smolt, and in special sensor

applications. The electromyogram (EMG) transmitter

for example, is designed to obtain, transmit and record

the electromyograms produced in the muscle of free

swimming fish as quantitative indicators of overall fish

activity in the laboratory or field.

Lotek’s Combined Acoustic Radio Transmitter

(CART) is the fusion of acoustic and radio frequency

transmitters into a single device. Through a

conductivity sensor, the CART device senses it’s

operational environment, saline vs fresh water, and

dynamically switches to the optimal mode of

transmission, acoustic vs radio. CART enables

researchers to monitor the migration of anadromous

species such as Pacific salmon from ocean through to

spawning site with a single transmitter. These same

researchers are quick to appreciate the ability to switch

between ultrasonic and radio monitoring; an inherent

system attribute of Lotek’s SRX_400 receiver. The

SRX_400 is a rugged 4 MHz telemetry

receiver/datalogger, which provides the basis for cost

effective yet comprehensive systems for unmanned,

remote data acquisition for coded or uncoded

transmitters. These field proven systems bring to the

manager and researcher multi-tasking capabilities for

such diverse functions as manual tracking, automatic

data logging and direction finding. Lotek Engineers are

currently developing an innovative receiver technology

that will be able to discern sonic signals at a lower

signal-to-noise ratio than possible with existing

technology.

As open ocean studies are extremely challenging,

many research groups have moved to Archival or Data

Storage Tag research programs. Lotek’s archival tag

utilizes a light sensor to measure ambient light levels

to obtain navigational information and is supplemented

with sensors that measure pressure and temperature.

The data transfer mechanism is an infrared optical link

and it has 1 Mbyte of flash memory.
38 Acoustic and Archival Tags: Applications to Salmonid Research
Acoustic and Archival Tags: Applications to Salmonid Research 39

Discussion Groups and

Workshop Recommendations

Following the presented papers at the workshop, two discussion groups were

convened on the topics of “biology, ecology, and oceanography” and

“technology” as applied to the application of acoustic and data logging tags to

salmonids. The discussion groups were held sequentially so that all participants

could contribute. From the discussion groups came a series of workshop

recommendations, which are included in this section.
40 Acoustic and Archival Tags: Applications to Salmonid Research

Group Discussion: Salmonid Biology, Ecology, and Oceanography;

What can be learned from acoustic and data logging tags?

Discussion Leader: Kate Myers

This group discussion was initiated with a series of

non-exclusionary questions posed in the agenda, as

follows:

 • What do we need to know about the movements of

salmon in estuarine, nearshore, and the open ocean

at varying scales that is not available from current

sources?

 • How can we best measure the role of environmental

and habitat factors in salmon habitat utilization and

movements?

 • What are the most important life history stages,

habitats, and geographic scales to address these

questions and what can be gained from the

application of smart tags?

 • What priority order should be given these research

issues?

As background, several topics were discussed.

First, the magnitude of the problems suggests a critical

need for a collaborative effort. Salmon stocks are often

mixed at sea. Different national fisheries may take

returning fish (with problems of interceptions).

Pooling limited funding and scientific resources will be

required. There is also an important need to show the

relevance of recommended research to either fisheries

management or to questions dealing with the

Endangered Species Act (ESA) in the US.

Participants also noted that we should focus on the

most important issues but must be realists in

determining what can be reasonably accomplished. The

group agreed to initially focus the discussion on what

can be done with existing technology and then move

toward broader objectives to give the engineers and tag

technologists information that can help with future

design requirements. 

Estuarine and Early Offshore:

Residence and Movements

Many important questions exist about estuarine

residence and movement into the nearshore

environment. Generally, participants agreed that the

most important problems were associated with juvenile

salmon; adult movements up-estuary are rapid and may

not be an issue in survival (with the possible exception

of longer-term residence in locations like Puget Sound).

For juveniles in estuaries, the fundamental question of

interest is the role of estuarine residence in survival.

Do different groups of fish (hatchery vs. non-hatchery,

early versus late season fish) show different residence

behavior? Are there survival differences between fish

that move immediately to the ocean as opposed to those

that remain in nearshore areas? Acoustic or recording

tags may not be the appropriate tool to address these

questions.

Some participants felt that estuarine residence is

not a period in the life history that contributes

significantly to variability in survival; instead, the

period during and immediately after ocean entry may be

more important. As an example, tagging studies in the

Columbia River have shown that juvenile salmon move

rapidly through the estuary and directly to sea water. 

Two kinds of studies were described to address these

issues. First, double tagging studies (with conventional

tags) and estimation of numbers can help determine

relative survival. Second, transplant experiments (e.g.

different release points, such as barging fish offshore)

allow one to examine differences in survival among

groups of returning fish. The results of these

experiments have been equivocal. Campbell River

studies suggest that estuarine residence is important to

subsequent survival, but in Scandinavia, results were

the opposite. Well-designed conventional tagging

experiments are needed for this kind of research because

large numbers of fish can be tagged at a reasonable cost,

but experiments with acoustic tags would provide

scientific information critical to understanding

mechanisms of movement and habitat utilization in

estuarine and nearshore waters.

Current technology in acoustic tags can be used to

address the problem of how larger juveniles move

through the estuary, but the large size of the data

logging tags currently available limits their utility for

use in small juveniles. Acoustic tags that identify

individual fish with moored recorders (detection ranges

of 100 to 250 m) can give spatial and temporal

locations of fish which can be used to calculate

movement rates within the estuary and nearshore area,
Acoustic and Archival Tags: Applications to Salmonid Research 41

as has been done with Atlantic salmon (Lacroix, in

press). It was suggested that this could be done in the

more exposed west coast nearshore regions as well, but

that some kind of longline arrangement of the recording

detectors would be required, and the logistics would

obviously require a significant investment in hardware.

Such research is continuing on Atlantic salmon. It was

suggested that the Columbia River is not the right place

to do the initial research because of its size and the

weather constraints. At least for a demonstration

project, justification for working in a smaller system is

appropriate; locations could include Willapa Bay or

Tillamook Bay, but in these systems the role of

predation may be very high, decreasing the return of

tags. There was also considerable discussion of concern

about tag loss to predation and about tracking predators

after tagged fish were ingested. 

Pending outcome of the issues noted above,

knowledge of habitat utilization in the estuary may or

may not be a universally important problem. The

numbers and body size of fish that can be tagged with

acoustic tags is limiting, but this type of experiment

would be quite useful for examining differences between

groups of one species or between species. Application

of acoustic tags to assess habitat utilization may

appropriately address questions of specific importance to

endangered or threatened species, particularly in

urbanized estuaries subject to anthropogenic impacts.

Little is known about depth, salinity, and physical

habitat preferences and how they change (for example on

a diel basis and with increasing residence time). In San

Francisco Bay, for example, most research effort is

devoted to examination of what happens as fish enter

the mixing zone. Concerns exist about whether fish are

diverted from the system, which runs are most greatly

affected, and for those not diverted, whether they are

moved into areas suboptimal for growth and survival.

An additional concern is to evaluate the impacts of

habitat alteration on these species. Application of

acoustic tags may be difficult, however, because

chinook in the San Francisco Bay estuary are only 80-

85 mm in length and average 6.5 gm in weight.

Application of acoustic tags to juvenile fish is a

general concern. Experiments to determine the tag

carrying capacity of fish of different size, tag-induced

mortality, and variations in behavior of the fish caused

by the tag are all important. What are the appropriate

tagging sites? Should the tag be internally planted or

perhaps put into the dorsal musculature? What are tag

rejection rates? Research on applications of new

biomedical technology could seek better ways to

promote tag acceptance and subsequent competence of

the fish (see abstract by Kynard and Kieffer). Finally,

biologists need to give specific information to

technologists with respect to features of the tag

important to the fish (dimensions, materials, shape,

etc.). 

Coastal, Maturing, and Returning

Salmon

In the open ocean, the larger size of fish leads to a

wider range of technology available to address important

problems. While traditional tagging can provide

information on population movement patterns and

survival, acoustic and recording tags afford the ability to

fill in important details (habitat utilization, relationship

of distribution and movement to oceanographic factors

on different time and space scales, etc.). This

information is deemed of high value. Two general

points about using acoustic or recording tags were

discussed. First, although the costs of these tags may

be high, the relative costs of the tags are not that high

when amortized over the total cost of the project. The

use of conventional tags (for example in the high seas

tagging program) requires expenditures for ship time,

scientists (salary, benefits, and overhead), and collection

and analysis of tagging results. The large amount of

data that can be retrieved from relatively few recording

tags makes the results of high value (although with

current pricing it is obviously best to tag those species

and life history stages where survival and tag recovery

rates are highest). The second point was the importance

of the “eureka” principal. Although recording tags on

salmonids can answer well-defined hypotheses about

movement and habitat use, we may also discover

surprising new facts that will alter the way we view the

fishes’ interaction with its environment and lead to new

approaches to research.

With respect to large scale movements of salmon, a

broad goal is to understand when and where they first

move offshore and how and when they return as adults.

Given the reality of current technology, fish size, and

the likelihood of tag return, most discussion focused on

tagging on the high seas to learn more about the return

migration. Many of these research priorities were

discussed in light of the major management issues in

British Columbia salmon fisheries, which are also

important issues for most northern stocks. These
42 Acoustic and Archival Tags: Applications to Salmonid Research

issues are: i) the numbers of returning salmon, ii) the

timing of their return, and iii) the route taken for return.

From a management perspective, the run timing is

probably most important, followed by the numbers

returning, and the route taken on the return migration.

Numbers of salmon returning is perhaps the most

difficult problem, but for the purposes of this workshop

is not one amenable to solution by recording or acoustic

tags and was thus not discussed further.

Annual variability in the timing of salmonid

returns is likely associated with the last six months of

ocean life. Geographic location, timing of initial

migratory movements, oceanographic conditions, and

the route taken are all important features that may affect

run timing, and currently available archival tags have

the potential to provide this information. Migration

routes of salmon (which are important because they

affect interception of fish) are probably affected by ocean

dynamics in the coastal environment. 

There was considerable discussion of the type of tag

to use and of the best species to tag. Although acoustic

tags have been used to answer several questions about

behavior and habitat utilization by salmonids, there was

concern expressed about aberrant behavior in the first

several days after tagging. Short term tracks may

suffer from a variety of artifacts in behavior; research

will be required to document this. A good example is

shown by the disruption of normal diel patterns in depth

during the first four days of a chum salmon track as

compared to later in the track (see figure 9 in Ogura,

this volume). Pasting together short tracks from

several fish to develop a composite picture of behavior

may be also present a drawback, because of aberrant

behavior, differences between fish, and temporal and

spatial differences in environmental conditions. For

these reasons, long-term recording tags are deemed

preferable. While temperature and depth recording tags

in appropriate sizes are presently available, participants

agreed that geolocating tags are preferable if available

(see Technology Discussion, following).

The appropriate species to tag is an open question.

Sockeye salmon are good candidates for open ocean

tagging because they are large, commercially important,

and a strong database on conventional tag data exists.

Recent model predictions of behavior are also available

(see Healey and Thomson abstracts). It was suggested

that relatively few archival tag recoveries from Fraser

River sockeye salmon could be used to examine the

hypothesis on how migratory pattern relates to ocean

currents. Bristol Bay sockeye salmon have an

advantage because of their rapid return from the open

ocean, consistent timing from year to year, and an

excellent historical record of tag data. Maturing pink

salmon would also be an ideal species to tag because

recent high seas tagging in the Gulf of Alaska has

resulted in tag recovery rates of pink salmon up to 25%.

Although adult pink salmon are small (and thus

potentially less able to carry a tag), this high recovery

rate may enhance the likelihood of a returned tag, which

is deemed important for a demonstration project on

salmon. 

Tagging on the high seas involves a mixed pool of

fish, and there was considerable discussion about the

likelihood of being able to identify the stock of origin

of tagged fish. Non-intrusive approaches to stock

identification cannot identify the origins of individual

fish. This provided further support for an international

high seas tagging study, because fish tagged in the Gulf

of Alaska could return to either the US or Canada.

Finally, it was suggested that steelhead is a good choice

for an initial experiment because spawning females

could be tagged after their first return and released to

record data on the migration pattern in both directions.

Movement patterns on small to intermediate scales

are important to interception and fisheries interactions

and can be investigated with acoustic and recording tags.

It is important to resolve questions of whose fish (e.g.

Canada vs US) are whose and how oceanographic factors

effect movement patterns that result in interceptionrelated conflicts. A related problem is the difference in

movement between species and stocks that can lead to

management decisions on gear types, fishing times and

areas. The example was provided of steelhead being

captured in fixed gear. Assessment of swimming depths

of steelhead using acoustic tags revealed that they swam

much shallower than sockeye, the target species in the

fishery. This allowed modifications to the gear and

consequently continued fishing. A similar analogy and

approach could conceivably be attempted to address

questions of threatened or endangered stocks by better

identification of the movement patterns. New

recording tags, even lacking geolocation (i.e. only

time/depth/temp data loggers), could provide some of

this information at better cost effectiveness. Finally, it

was noted that migration models are often used to make

fishery management decisions for salmon. These tags

have the potential to either validate or falsify the models
Acoustic and Archival Tags: Applications to Salmonid Research 43

and thus improve management.

The majority of the discussion up to this point

centered on the highly abundant species for which large

scale research programs have been conducted. Research

issues for coho and chinook salmon are somewhat

different and involve the fundamental difference between

questions strictly related to fisheries management and

those associated with threatened and endangered species

(although it was noted that securing permits for acoustic

tagging studies on endangered species might be

difficult). Scientific and management questions about

run timing are important for these species. Broad

research questions concern the distance of their

migrations and their spatial and temporal use of the

ocean environment. Outer- and inner-coast populations

may have different coastal migratory patterns.

Understanding variability in survival may require

improved understanding of the specific ocean habitats

utilized. Migration patterns of southern stocks are

poorly known. Are their migrations restricted to coastal

areas or do they move far offshore? Several participants

believe that variability in survival occurs in the coastal

zone, when fish are young. 

Participants also expressed an interest in examining

metabolic costs and bioenergetics of fish at sea, both in

light of movement models (to better understand the

energetics and the food requirements during migration;

see abstracts by Helle, Healey and Thomson) and with

respect to growth and size at return. Electromyogram

(EMG) tags, presently available in relatively short term

acoustic versions, can provide proxy metabolic

information to examine growth. EMG capability is not

presently available, however, in recording tags.

Combining recording tag data, however, with

information on the broader environment (prey

abundance, temperature, currents) and comparing it with

location would be highly valuable; the last 6 months of 

life at sea are very important. Physiologists have

developed a theory that growth at sea may be set in

spring each year. This may be related to local

environmental conditions affecting the fish at that time,

and location from tags could answer the question.

Ocean location at different times determines the growth

or scope for growth, and growth rates can change

dramatically over 100-200 km; some ocean zones to do

not support much growth. 

Finally, research on the mechanisms through which

salmon orient to their environments was discussed in

some detail. Acoustic and recording tags (in some cases

with further refinements) have the potential to support

further understanding of olfactory mechanisms in

movements, compass or magnetic orientation, and

responses to oceanic stimuli. A question was raised as

to whether the level of variability observed in the field

will be sufficient to allow progress to be made.

Complicated experiments have been done on birds

(where the experimental logistics are much easier) but

controversy still rages over the roles of different

orientation mechanisms. Because this research area is a

more basic one and does not really address management

issues, it was generally given a lower priority by the

participants.

Concluding comments

Participants agreed that many of the research

projects discussed have great potential to answer

important questions dealing with both fishery

management and protected species issues. The group

strongly recommended that experiments go forth with

existing, tested technology. The results of the

experiments can be used immediately. Future research,

with improved technology, will benefit from the results

of experiments started immediately.
44 Acoustic and Archival Tags: Applications to Salmonid Research

Group Discussion: Current and Needed Technology for application

of acoustic and recording tags to salmonids

Discussion Leader: Kevin Friedland

This group was tasked with discussing the current

state of acoustic and recording tags, the technological

problems which exist for applications to salmonids, and

the highest priorities for development of new tags.

Salmonid tag carrying capacity and

associated problems

The initial discussion centered on what issues must

be resolved to improve our understanding of the

limitations of salmon for carrying tags. Different

species and life stages will have different tag carrying

abilities (see Table 1, Emmett and Dawley abstract, for

size information on young fish). Miniaturization can

only proceed to some finite point, and it may never be

possible to get a wide range of parameters on the earlier

life stages of salmonids.

Physiological assessment of tagging effects

 It was pointed out that many studies use mortality

as the endpoint of evaluating tagging effects, but that a

variety of sublethal effects may reduce fitness (feeding

ability, buoyancy effects, swimming performance and

stamina) and thereby affect the results from tagging

experiments. The approach of looking at heat proteins,

cortisol, or other physiological markers (see abstract by

Siri) is complex in itself, and some participants

suggested that alternative, simpler assays could be

developed to address tagging effects. It was

recommended that researchers in this area establish care

guidelines for handling fish by those tagging in the

field.

Choice of tagging site

The location of the tag on the fishes’ body can have

implications for fish health but also on the ability to

detect the tag (e.g. are fishermen going to notice an

internal tag, even if it has the light probe sticking out

in the case of an archival tag?). Europeans have a

preference for externally mounted tags (see contributed

abstracts by Metcalfe and Arnold, Sturlaugsson and

Gjudbjornsson). It is a high priority for manufacturers

to know what development approach to take. While

internal tags may be beneficial because of reduced tag

loss, scarring, and infection from the attachment points,

fish have the ability to extrude internal tags. The time

course of extrusion is likely species and tagging-site

specific and some new techniques may reduce extrusion

rates (see contributed abstract by Kynard and Kieffer).

Research on tag shape and form was encouraged.

State of tag development and priorities

for future development

Discussion of the current status and future needs

was made difficult by the complexity of the question.

The biologists were generally interested in new

technology to address specific problems, meaning a

variety of life history stages, species, sizes, and

measurement parameters. Manufacturers and

technologists hoped to see the problem narrowed to

more definable scope that could lead to a useful product

likely to be purchased in reasonable numbers. Specific

requests for information included the following:

 • the time factor; the required duration of a track is

important to determine battery life and/or memory

requirements;

 • optimal tag size for different fish sizes;

 • optimal attachment point (e.g. internal or external)

 • parameters to be measured.

Because of the complexity of the problem, the

Discussion Leader developed a set of tables to solicit

consensus information on the information available

now and that is most highly desired for both acoustic

and data logging tags.

Acoustic tags (Table 1): Acoustic tags provide

relatively short-term tracks but a variety of useful

information (see abstracts by Quinn and Ogura). A

variety of parameters can currently be measured, and

these tags exist in relatively small sizes at the present

time. The first three parameters (temperature,

geographic position, and salinity) were deemed high

priority but are typically not measured on-board the tag

because the system recording the data (whether a remote

logger or a vessel tracking the fish) can gather the

information in separate ways (e.g. XBTs used for

periodic temperature profiles). Depth is important for

all life history stages to assess habitat utilization.

Activity is most important for smolt and mature

seawater fish for assessment of bioenergetic parameters. 
Acoustic and Archival Tags: Applications to Salmonid Research 45

Compass heading can provide information on behavior

and orientation and is likewise of high importance.

Finally, “mortality” is particularly high priority for the

smaller life stages subject to high predation rates.

Several tracking projects have apparently followed

predators that have consumed the fish that was the 

subject of the track; knowing when the tracked fish was

consumed or another logical endpoint of the track would

be useful to minimize wasted tracking time.

Approaches to the latter parameter included tail beat

frequency measurements or pH sensors.

Temperature Position Salinity Depth Activity Compass

Heading Mortality

Parr

Smolt 4* 4* 4* 4 4 4 4

Postsmolt 4* 4* 3* 4 3 4 4

1SW

MSW 4* 4* 3* 4 4 4 2

Table 1. Identification of the priorities for information required from acoustic tags by life stage. Priorities range

from 0 (lowest, not advisable) to 4 (highest priority). An asterisk indicates that the parameter is not directly

measured by the tag, but rather by other instrumentation on the tracking platform or elsewhere. 1SW; fish after the

first year in the ocean. MSW; mature ocean fish. A blank box indicates that tagging is impractical in these life

stages at this time.

Data logging tags: Current capabilities of data

logging tags (Table 2A) begin with very few parameters

for small fish (smolt and post-smolt) but expand for

larger fish to include position, depth, activity (EMG, 

see abstract by Stoodley), and compass heading.

Salinity sensors are available on data logging tags, but

only for short durations due to fouling of the sensors. 

Temperature Position Salinity Depth Activity Compass

Heading

Parr

Smolt x

Postsmolt x

1SW x x x* x x x

MSW x x x* x x x

Table 2A. Present sensor capabilities of data logging tags. An “x” in the box indicates that such information is

feasible for a given life stage. Blank boxes indicate the lack of a measured parameter. The asterisk for salinity

sensors indicates that these are available for relatively short duration records only.
46 Acoustic and Archival Tags: Applications to Salmonid Research

The desirable parameters to be recorded in a data

logging tag vary with life history stage. The priorities

for these parameters, and for development of different

life stages, was evaluated by the group (Table 2B).

First, the most important life stage for data logging tag

experiments are mature ocean fish, followed in order by

post-smolts, smolts, and first-year ocean fish. It was 

deemed unlikely in the foreseeable future that the

technology for data logging tags for parr would be

available. Temperature, position, and depth were

accorded the highest priorities for parameters to be

logged. With the exception of smolts, salinity is

relatively unimportant. 

Temperature Position Salinity Depth Activity Compass

Heading Life Stage

Parr 4 0 0 0 2 0 0

Smolt 4 0 4 4 3 2 2

Postsmolt 4 4 2 4 3 3 3

1SW 4 4 2 4 3 3 1

MSW 4 4 2 4 3 3 4

Table 2B. Identification of the priorities for information required from data logging tags by life stage. Priorities

range from 0 (lowest, not advisable) to 4 (highest priority). Life stage indicates where greatest priority should be

placed for development of tags.

Other technological considerations

discussed in the session

Tag and sensor evaluation was seen as a high priority.

Benchmark tests of existing tags (see abstracts by

Klimley and Welch) have shown variability among

tags, particularly in the geolocating capability. Stated

accuracy was not always met. Static in-situ tests of

geolocating archival tags were highly recommended, as

were assessments of the accuracy of position estimates

as function of wind or sea state. It was also suggested

that until algorithms for geolocation are uniformly

agreed upon that raw data be recorded so that alternative

algorithms can be used after the tags are returned. It

was noted that this might require additional data storage

requirements, and that this might conflict with

development of proprietary algorithms for geolocation.

Cooperation and communication in developing

tags. Significant up-front cost exists in developing tags

with new applications, and manufacturers are often

unable to do the needed developmental work without the

likelihood of a reasonable market. The question was

addressed whether there should there be some kind of

industry/academic/government cooperation to develop 

tags. This would depend upon funding, and no sources

were readily identified. It was clear, however, that in

order to assure adequate numbers of tags to be produced

that there would have to be some agreement among

scientists regarding the type and nature of the tag to be

developed.

Participants also noted the importance of keeping

up with new technology. Several manufacturers not

present at the meeting have products that may be useful

for applications to salmonids if some compromises are

made. It was also suggested, but not universally

supported, that a “smart tag homepage” could be

developed for passing on information and continued

discussion; an alternative also discussed was a listserver

for interested scientists.

Alternative technology and techniques were also

suggested. An alternative, easier way to take a proxy

measurement for the current EMG sensors but not

requiring surgical implantation is desired. Military

sonobuoys have the potential be dropped from airplanes

to track fish if the fish tags were appropriately designed.

Canadian, US military have the capability to air deploy

systems to listen to passing signals.
Acoustic and Archival Tags: Applications to Salmonid Research 47

Workshop Recommendations 

A total of 17 recommendations was developed after

the meeting through a process using the following

steps: first, preliminary recommendations were

generated through a review of the notes of the two

discussion groups. This list was distributed to all

participants with a request for comments, including

modification of those provided and generation of new

recommendations. After editing and the addition of a

short description clarifying each recommendation, they

were again distributed to the participants for a voting

procedure intended to develop a set of priority

recommendations. The workshop recommendations,

with short clarifying text for each, are provided below,

listed in the order of priority given by the participants.

Salmonid Biology, Ecology, and

Oceanography; Recommendations

A4. Field a high-seas tagging study using existing data

logging tags (e.g. temperature, depth) on adult salmon

in the Gulf of Alaska, concentrating on species where

survival and tag recovery rates are high. 

 • Currently available data logging tags that record

temperature and depth have been applied

successfully to Atlantic salmon. This type of tag

could be employed immediately to demonstrate the

utility of the technology to Pacific salmon research

while other, more complex tags are being developed

and evaluated.

A2. Assess the mechanisms of movement and habitat

utilization by post-smolt Pacific salmon in nearshore

coastal waters using acoustic tags. 

 • During and shortly after ocean entry, young salmon

are subject to high predation rates and a new

environment. Several participants believe that this

is a period of perhaps highest mortality and a

source of interannual variability in mortality.

Several approaches, including moored recorders to

follow multiple fish, were discussed at the

workshop.

A7. Field a tagging study with geolocating data logging

tags on west coast adult chinook and coho to determine

migratory patterns.

 • Research is needed to resolve uncertainty about

movement patterns and ocean habitat utilization

(e.g. coastal versus open ocean residence) for these

species.

A6. Field an international high-seas tagging study using

geolocating data logging tags on sockeye salmon.

 • This study could address migration patterns, and run

timing, and evaluate the hypothesis on how

migratory pattern relates to ocean currents and water

mass properties.

A3. Assess the mechanisms of movement from

nearshore waters into the estuary and habitat utilization

in estuarine waters by returning adult salmon using

acoustic or data logging tags. 

 • How do adults find and enter the estuary? How fast

do they move up the estuary and what habitats are

used during the passage?

A5. Field a research program tagging adult female

steelhead (in freshwater) with geolocating data logging

tags to determine the migratory path to and from the

high seas.

 • Steelhead have the advantage of survival after

spawning, so that fish can be tagged in freshwater

and held before release. They also have the

advantage that data would be recorded for the entire

migration track, to and from the high seas, and a

reasonable likelihood of tag recovery.

A1. Assess the mechanisms of movement and habitat

utilization by juvenile Pacific salmon in estuarine

waters using acoustic tags. 

 • Juvenile salmon moving down the estuary typically

move rapidly and also suffer high predation. How

they move through the estuary and the preferred

habitats during estuarine residence need to be

evaluated.

A9. Use acoustic tags to determine how salmon orient

to environmental gradients and cues.

 • Olfactory mechanisms, compass or magnetic

orientation, and responses to oceanic stimuli are all

hypothesized to be important in salmon

movements. Acoustic tagging experiments can

address certain of these questions.

A8. Use acoustic tags with EMG capability on adult

sockeye salmon.

 • The purpose of this work would be to examine

metabolic costs of foraging, migrating, and

escaping, on the high seas and in coastal waters.

Results would allow a better understanding of
48 Acoustic and Archival Tags: Applications to Salmonid Research

growth and biophysical influences on how sockeye

lay down their energy reserves for up-river

migration and spawning, and would allow testing

and improvement of existing models.

Technology Needs for Salmonid

Tagging; Recommendations

B1. Calibrate (in laboratory) and verify (in field) the

precision and accuracy of acoustic and data logging tags

and their sensors. Establish protocols for sensor

calibration and evaluation.

 • Applications of acoustic or data logging tags on the

larger scales discussed at the workshop will be an

expensive proposition. Manufacturers need some

assurance of a market for products, but scientists

proposing research funds to buy tags must

demonstrate the important scientific problems

being addressed as well as an accurate sensor that

will provide reliable data. New developments in

tags, modifications to sensors, and changes in

algorithms for derived parameters can all affect tag

performance. Reliable standards for calibration are

required.

B6. Continue miniaturization of acoustic and data

logging tags to allow use in early life history stages.

 • Tag size continues to be a problem with

application of acoustic and data logging tags to

salmonids, particularly younger fish. Research and

development efforts are required to decrease size of

existing tags, and to improve sensors, increase

memory capability, and develop new sensors for

applications in salmonids.

B8. Evaluate effects of tags on salmon and the capacity

to carry tags.

 • Tags have impacts on survival, behavior, and

growth. There are also concerns about tag rejection

and retention, including extrusion of internally

planted tags. Questions of optimal tagging

location, internal versus external attachment, and

other tag effects should be evaluated before

undertaking long-term studies with acoustic or data

logging tags. Laboratory research with dummy

tags evaluating sublethal effects are required.

B2. Develop and verify geolocating algorithms for data

logging tags that will minimize problems of horizon on

the coast and east-west movement of fish.

 • Geolocating algorithms using light level have

unknown biases from east-west movement of fish

and for variability in the horizon when near the

coast. Research should be conducted to evaluate

these problems and find solutions.

B7. Develop methodology for tracking fish with

acoustic tags for periods of weeks and for tracking more

than one fish at a time. 

 • Longer tracks and multiple fish tagging programs

are needed to increase the number of observations

and decrease likelihood of aberrant behavior early in

the tracks. Some new technology is presently

available for this and further improvements are

needed. 

B4. Develop proxy parameter for metabolic utilization

in acoustic and data logging tags.

 • EMG tags require surgery and implantation of

electrodes. Although they work for fairly short

term implantations, the electrodes may not be

sufficiently reliable for longer-term recordings.

Sensors to record proxy variables, such as

swimming speed, may provide similar information

with less complex implantation requirements.

B3. Develop sensor and geolocating algorithm using

geomagnetic fields.

 • Geomagnetic fields represent a potential mechanism

for determining geolocation. Development of

appropriate sensors in the sizes required for a data

logging tag and research on appropriate algorithms

are needed.

B5. Develop cooperative program with defense agencies

for development of new technologies applicable to fish

tagging.

 • At the workshop, the example of air-deployed

sonobuoys to serve as listening stations for

acoustically tagged fish was raised. There may be

additional technologies applicable to the problems

faced in acoustic and data logging tags and these

should be evaluated.
Acoustic and Archival Tags: Applications to Salmonid Research 49

Ev al ua ti o n o f Wo rk s h o p

Recommendations

Voting was conducted to place priorities on the

workshop recommendations. All participants were

given the opportunity to vote for five recommendations

in each of the two categories (“biology, ecology, and

oceanography” and “technology”). All but five

participants did so. In the interpretation of the priorities

that follow, it is useful to note the distribution of

expertise at the meeting. Of the 28 participants, only 6

would be classified as technologists or engineers, and

the remainder would fall within the category of

biologists, oceanographers, or ecologists. Because all 

of the five non-voting participants were technologists or

engineers, the priorities described below do not represent

their opinion.

Votes were tallied in two ways. First, five points

were assigned to each first place vote, four for the

second place votes, and so forth to one point for a fifth

place vote; the sum of these scores are referred to as

“rank total”. We also summed votes independently of

the ranks, and these are listed as “vote total.” The first

seven of the nine recommendations under “biology,

ecology, and oceanography” all scored quite highly

(Figure 1). 

0

1 0

2 0

3 0

4 0

5 0

6 0

7 0

8 0

A1A2A3A4A5A6A7A8A9

B1B2B3B4B5B6B7B8

Rank Total

0

2

4

6

8

1 0

1 2

1 4

1 6

1 8

2 0

A1A2A3A4A5A6A7A8A9

B 1B 2B 3B 4B 5B 6B 7B 8

Recommendation Number

Vote Total

Figure 1. Summary of voting on the workshop recommendations. The upper panel

represents the rank total, the lower panel the vote total. Recommendations are listed in

the text.
50 Acoustic and Archival Tags: Applications to Salmonid Research

The highest priority recommendation (A4) was to

undertake a “demonstration project” to use existing data

logging tags as soon as possible. Existing tags would

have a lower number of measured parameters than may

be desirable, but there is high value in proving the

value of data logging tag results to understanding

salmon movements and habitat utilization (as has been

done for Atlantic salmon -- see Sturlaugsson and

Gudbjornsson, this volume). Similarly, strong support

for understanding movements of young fish

immediately after the transition from estuarine to

marine waters (A2) reflects the opinion of many that

this may be a point in the life history when survival is

highly variable (see Pearcy, this volume). Use of

existing acoustic tags, perhaps with an array of moored

recorders (see Lacroix, this volume), could help evaluate

how these fish move and utilize the nearshore and

coastal environments. There was also support,

however, for assessing movements of young fish within

the estuary (A1) and of adults moving into the estuary

on the return migration (A3). Application of

geolocating tags in the open ocean was also supported

strongly (Figure 1) for west coast chinook and coho

salmon (A7), sockeye salmon (A6), and steelhead (A7).

Recommendations to use acoustic tags with EMG

capability on adult sockeye salmon (A8) or to use

acoustic tags to determine how salmon orient to

environmental gradients and cues (A9) received

relatively few votes; this may be due to the perception

that assessment of metabolic activity and orientation

mechanisms may have been less pragmatic (and

 feasible) than research proposed in the other

recommendations dealing with habitat utilization and

movement patterns. 

Distribution of voting for the technology-related

recommendations better identified priorities, with four

of the eight recommendations receiving the bulk of the

votes (Figure 1). The calibration and verification of tag

precision and accuracy (B1) was ranked as the highest

priority need by participants; this is already the topic of

active discussion (see abstracts by Klimley and

Holloway, this volume and Welch, this volume) and

field tests are underway (D. Welch, personal

communication). Discussion of this point at the

workshop, however, seemed intent on sending a

message to tag manufacturers that this must be a

continuing endeavor as new tags are developed. The

second priority was placed on continued miniaturization

of tags (B6), reflecting the desire to extend the ability to

apply tags to earlier life history stages of salmonids

while minimizing tagging stress. This goes hand in

hand with the need to evaluate tagging effects and

conduct research on the ability of different species and

life history stages to carry tags (B8), which, along with

improvement in geolocating algorithms (B2), was the

next highest priority. The remaining four technology

recommendations (B3, B4, B5, B7) were less highly

supported in this exercise. Again, these four represent

longer-range objectives and may thus have been

considered less pragmatic by many of the participants.
Acoustic and Archival Tags: Applications to Salmonid Research 51

Appendix 1:

Contributed Abstracts

Several researchers conducting studies pertinent to the workshop and tag

manufacturers unable to attend were asked to submit abstracts as a means of

increasing the information content of the workshop report and promoting

communication among researchers. 
52 Acoustic and Archival Tags: Applications to Salmonid Research

Tracking of Atlantic salmon (Salmo salar L.) and

sea trout (Salmo trutta L.) with Icelandic data storage tags

Johannes Sturlaugsson, The Institute of Freshwater Fisheries, Vagnhofdi 7, 112 Reykjavik 

Iceland Tel: (+354) 567 64 00 Fax: (+354) 567 64 20 E-mail: johannes.sturlaugsson@itn.is

Sigmar Gudbjornsson, Star Oddi Ltd., Grandagardur 5, 101 Reykjavik Iceland

Tel: (+354) 551 34 44 Fax: (+354) 551 34 44 E-mail: star-oddi@prim.is

Introduction

The data storage tag (DST) was developed in Iceland

by the engineers at Star Oddi Ltd. in co-operation with

fish biologists at the Institute of Freshwater Fisheries

and the Marine Research Institute in Iceland. These tags

record series of measurements from the environment of

the fish. They record pressure (depth), temperature and

conductivity (salinity). The small size, low weight and

cylindrical shape of these data storage tags make it

possible to use the tag on relatively small fish. 

The Institute of Freshwater Fisheries has used the

Icelandic DSTs in Icelandic waters on Atlantic salmon

(Salmo salar L.) from 1993-1996 and on sea trout

(Salmo trutta L.) from 1995-1996 (Sturlaugsson 1995;

Sturlaugsson and Johannsson 1996, 1997). In addition,

the Institute of Freshwater Fisheries has participated in

research on Baltic salmon (Salmo salar L.), where these

tags were used, from 1995-1996 (Karlsson et al. 1996).

The salmon were tagged externally, but the sea trout

were tagged both externally and internally. A total of

310 salmon and 110 sea trout have now been tagged

with DSTs in Icelandic waters.

In the DST tagging experiments in Icelandic

waters, the main aim was to study the homing

migration of salmon in coastal waters and the sea

(feeding) migration pattern of sea trout. These studies

were the first instances of DSTs used in research on

these species. The Icelandic DSTs are both the smallest

and, by far, the least costly data storage tags on the

market. Therefore, the Institute of Freshwater Fisheries

has been able to tag and recapture high numbers of fish

of diverse sizes (39-96 cm). This was done in order to

determine, as closely as possible, the common

behaviour of these migrants. Different intervals

between recordings were used to examine more closely

the swimming behaviour (1,5 minute intervals) and

diurnal rhythms (DSTs with two different measuring

time series, that are repeated). In the case of salmon,

different environmental circumstances were used to look

at possible effects on the migration pattern. As an

example, salmon were released both coastally and

off-shore at varying depths. They migrated both against

and along the main sea currents over distances ranging

from 25-420 km (shortest sea route). Control groups of

salmon were tagged with DSTs and kept in net pens in

the sea, enabling comparison with the salmon

migrating at that time.

The use of DSTs provided new methods of

sampling series of data directly from the fish ́s

environment, and over longer periods of time in the sea

than previously possible. For example, we have

received a series of vertical movements and

corresponding water temperatures, from the sea trout

studies, for time periods up to 5 months. These data

series were also the first instances of such

measurements that included the sea phase throughout

the study and the freshwater phase before and after sea

migration.

Results of migration studies on homing

Atlantic salmon

A high recapture rate of tagged salmon (20-60 %)

gave large series of recordings showing that the salmon

spent most of their time close to the sea surface, as has

been reported. But, the recordings also included much

information concerning the poorly documented diving

activity that occurs occasionally. This new information

included dives made by the salmon down through the

thermocline, and dives that were both deeper (down to

153 m) and faster (vertical speed up to 0,73 m/sec) than

had been reported previously in coastal waters. The

reasons for the diving activity of homing salmon are

not always the same. Certain known facts or

hypotheses give these reasons for dives while homing:

excursions to scan the different environmental

parameters as cues for orientation, selective tidal

transport, thermoregulation, escape behaviour, and

feeding (seldom).

The salmon experienced diversity in the temperature

and salinity, and the largest changes in a short time
Acoustic and Archival Tags: Applications to Salmonid Research 53

were recorded at the same time as excursions into deep

water, estuaries or rivers. Examples of extreme

changes in temperature and/or salinity in a very short

time are good indicators of the versatility of salmon.

The salinity sensor was first used in 1996, and the first

results show very interesting behaviour regarding the

coastal migration, especially in relation to the estuaries.

The water temperature recorded reflects the vertical,

estuary or river migration pattern and also gives

possibilities for tracking the horizontal location of

migrating salmon, in general, close to the sea surface

over large areas. By comparing temperature data from a

DST to sea surface temperature data from satellite

measurements, it is possible to locate the area

(temperature zone) to which the fish are migrating.

 Because the salmon is frequently in close proximity

to the surface, the sea temperature in coastal waters is

often correlated to the air temperature in the area.

Relatively high temperatures experienced by salmon,

combined with their common non-feeding behaviour

during spawning migration, resulted in as much weight

loss as 10% within 1 month.

Development of new generations of

DSTs 

The on-going development will result in a release

of the new generation DST 300 in November of this

year. Reduction of size and weight has been the main

object (Table 1).

Table 1. The types of available Icelandic DSTs. Parameters involved are listed with reference to specification of

each tag type.

PARAMETER DST 200 DST 300 Units

Size (diameter/length) 18/48 13/46 [mm]

Weight (in air/in water) 12/0 8/1 [gram]

Memory 8.100* 8.100* [number]

Maximum depth >450 >700 [meter]

Temperature range customer specified from -25 to +50 [ ̊C]

Depth range customer specified from 0 to 600 [meter]

Salinity range customer specified, 5 to 37

Tilt angle customer specified, +45 to -45 [ ̊]

Lifetime >12** target 12** [month]

*Increased to approx. 16.300 in near future **Depending on temperature and number of measurements

The next steps taken in the DSTs ́ development in

Iceland will involve further reduction of size and weight,

expansion of memory, expansion of life time,

development of new sensors (5) and specification of

complete customer chip solutions.

General conclusions and future

perspectives

The data storage tags will be very important

research tools in fisheries research in the future. They

will open new methods of studying the behaviour and

environment of fishes, not the least of which will be

the anadromous fish. This is due to the fact that the

DSTs enable unique possibilities regarding sampling

continuous series of special, behavioural, and

environmental information from areas and over time

periods where other sampling methods can not be used,

or are both too difficult to use and too costly, which

often results in limited data. This new dimension in

research of fish will therefore add valuable information

to our understanding of fish behaviour and their

reactions to their environment. Additionally, the results

from DSTs tagging can, in some instances, be useful in

improving the traditional sampling methods.

In the coming years, the Institute of Freshwater

Fisheries will continue to use DSTs in research on

salmonids in the sea. In the case of Atlantic salmon,

the main activity will be in tagging experiments
54 Acoustic and Archival Tags: Applications to Salmonid Research

involving feeding migration in the sea, with a

combination of tagging of kelts and large

smolts/postsmolts. This will also introduce very

interesting ways of comparing growth to sea

temperature circumstances.

References

Karlsson, L., Ikonen, E., Westerberg, H. and

Sturlaugsson J. 1996. Use of data storage tags to study

the spawning migration of Baltic salmon (Salmo salar

L.) in The Gulf of Bothnia. ICES. C.M. 1996/M:9. 16

p.

Sturlaugsson, J. 1995. Migration Study on Homing of

Atlantic salmon (Salmo salar L.) in Coastal Waters

W-Iceland - Depth movements and sea temperatures

recorded at migration routes by data storage tags. ICES.

C. M. 1995/M:17. 13 p. 

Sturlaugsson, J. and Johannsson M. 1996. Migratory

pattern of wild sea trout (Salmo trutta L.) in SE-Iceland

recorded by data storage tags. ICES. C. M. 1996/M:5.

16 p. 

Sturlaugsson, J. and Jóhannsson, M. 1997. Migration

study of wild sea trout (Salmo trutta L.) in SE-Iceland:

Depth movements and water temperatures recorded by

data storage tags in freshwater and marine environment.

Proceedings of Fifth European Conference on Wildlife

Telemetry. Strasbourg, France 25 -30 August 1996. 10

p. (In press).

_____________________________________________________________________________________________

Rejection of internal telemetry transmitters by shortnose sturgeon

Boyd Kynard and Micah Kieffer, USGS, Conte Anadromous Fish Research Center, Turners

Falls, MA. 01376. Phone:(413)863-8993, Ext. 42; Fax:(413)863-9810.

From 1988 to 1996 we identified the rejection

incidence of internal transmitters placed periodically in a

total of 57 adult shortnose sturgeon Acipenser

brevirostrum (71 - 112 cm TL) inhabiting two

Massachusetts' rivers. Transmitter fate was determined

using tracking, double tagging individual fish with

internal and external transmitters, and observations of

recaptured fish for tag presence and position in the body.

Twenty fish were tagged with ultrasonic transmitters in

the Merrimack River; 36 fish were tagged with radio

transmitters in the Connecticut River. All transmitters

were cylindrical, about 115 mm long x 16 mm

diameter, with a 2-year battery life. The external

surface of the initial nine ultrasonic transmitters was

ABS plastic, the remaining 11 tags were coated with

Silastic. Radio transmitters were also coated with

Silastic, an elastomer from Dow Corning Corporation

that is used to coat electronic devices for implantation

 in humans. Rejection incidence of ultrasonic

transmitters was 33 % for uncoated transmitters (3 of

9), and zero for the 11 coated transmitters. Rejection

was 21 % for 19 radio transmitters used in 1993 that

had short 4-cm-long antennae. Zero transmitters with

2-6 cm long coiled antennae used in 1994-1996 were

rejected (n = 17). (Five fish tagged in 1996 that retained

tags for six months are included in this total.)

Rejection of ultrasonic tags occurred quickly (within 2

weeks); whereas, radio transmitters were rejected within

14 weeks (mean = 7.6 weeks) except for one transmitter

rejected at 72 weeks. There was no obvious

relationship between fish length and rejection. Our

results show that some shortnose sturgeon reject

internal transmitters by pushing them through the

peritoneum wall and out the anus, and coating

commercial transmitters with Silastic can greatly reduce

rejection.
Acoustic and Archival Tags: Applications to Salmonid Research 55

Tracking of Post-Smolt Atlantic Salmon into Coastal Areas of the Bay of Fundy

Gilles L. Lacroix, Fisheries and Oceans Canada, St. Andrews Biological Station, St. Andrews,

NB E0G 2X0, Canada

Several novel studies were conducted in 1995 and

1996 as a result of the collaboration between the

Atlantic Salmon Federation and the St. Andrews

Biological Station (Fisheries and Oceans Canada) to

track the movement of Atlantic salmon during the early

stage of their seaward migration in coastal areas of the

Bay of Fundy in New Brunswick, Canada. The goal

was to examine the hypothesis of increased natural

mortality in the marine environment used to explain the

recent declines in Atlantic salmon stocks. For this, we

needed to obtain direct evidence of the mortality, when

and where it occurs, and then to identify the factors

responsible. Our recent involvement with VEMCO

Ltd. in the research and development of ultrasonic

telemetry gear has provided us new tools to do this.

In 1995, pulsed low frequency acoustic pingers

(VEMCO V8 Series Expendable "Intelligent"

Transmitters) were surgically implanted in the abdomen

of 96 hatchery-reared smolts while in freshwater.

Hatchery smolts which were considerably larger fish

than wild smolts were used because of the limits

imposed by the size of pingers (8 mm diameter x 36

mm length) at that time. Groups of 48 smolts with

pingers were then released at the head of tide in the St.

Croix and Magaguadavic rivers at the time of natural

smolt migration in May. The movement of smolts

from the rivers into Passamaquoddy Bay was monitored

with an underwater receiver (VEMCO VR20-Monitor;

an automated submersible pinger detection receiver for

remote monitoring) moored underwater at the mouth of

each river. Each unit had a radius of detection in excess

of 0.25 nautical miles. Movement of post-smolts from

Passamaquoddy Bay into the Bay of Fundy was then

monitored using a network of 10 automated underwater

receivers deployed to cover all outlets from

Passamaquoddy Bay. These units were moored at depths

of up to 90 m in areas of extreme tidal currents. Each

unit could detect individual pingers according to their

frequency and pulse period and could store the time of

passage of a tagged fish. 

The efficiency of the network of underwater

receivers at detecting the passage of individual fish was

excellent. Post-smolts were usually detected by at least

two units when moving out of Passamaquoddy Bay.

Searches for fish were also made daily during June by

crews on several boats equipped with receivers for

pinger location and tracking (VEMCO VR60 Ultrasonic

Receiver) equipped with both directional and

omnidirectional hydrophones (VEMCO VH32 and V10

Hydrophones). In addition, surveys were made to detect

if post-smolts were caught in the many herring weirs

along the coast and to determine if post-smolts were

attracted to or affected by the presence of numerous

marine cage sites for the culture of Atlantic salmon in

the Passamaquoddy Bay area. 

In 1996, a new single-chip pinger was developed by

VEMCO Ltd. over the winter which allowed for size

reduction (8 mm diameter x 26 mm length) and use in

wild salmon smolts. The new pingers were surgically

implanted in the abdomen of 38 wild smolts during

May. These were captured in freshwater at the mouth of

the Magaguadavic River after they had passed

downstream of the power dam in St. George. The

surgery on the small wild smolts was successful, and

fish were released 24 hours later at the head of tide in

the river. The fish were then tracked with hydrophones

and receivers aboard boats and their movements from the

river estuary into Passamaquoddy Bay and from there

into the Bay of Fundy were monitored using automated

receivers moored underwater at the same strategic

locations used in 1995 to monitor the large hatchery

fish. As before, each individual fish tagged could be

recognized because each pinger had a different pinging

rate. 

The performance of the new pingers was excellent.

Their range of detection was equal to and often greater

than that of the larger pingers used in the past, and the

duration of one pinger tested exceeded 3 months. Their

smaller size (26 mm long compared to 36 mm in the

past) made it possible to successfully implant them in

the small wild fish. This is a major breakthrough in

telemetry of small fish in sea water, and it greatly opens

up the possibilities for research. The duration of the

pinger also means that fish can be tracked over long

distances in their migration to feeding grounds and

overwintering areas.
56 Acoustic and Archival Tags: Applications to Salmonid Research

Both studies were highly successful. The

behaviour of smolts upon entry into sea water was

examined and their success at leaving river estuaries was

determined. The migration routes used by post-smolts

after leaving the rivers were then determined from

position fixes of fish detected throughout

Passamaquoddy Bay and site of detection upon leaving

the bay. This was examined in relation to tidal stream

and surface currents. The success of post-smolt

migration from Passamaquoddy Bay into the Bay of

Fundy was then successfully determined using the

network of underwater receivers. The sites where

post-smolts were lost also allowed us to identify

potential areas and sources of mortality. 

In summary, the studies successfully followed the

movement of hatchery-reared and wild Atlantic salmon

 at an early stage over relatively long distances in sea

water. It effectively sealed off a large coastal area such

that all fish surviving and moving through the network

of automated underwater receivers could be detected. A

comparison of the success, behaviour, and migration

routes of wild post-smolts with those of hatchery origin

was conducted. The new pingers proved highly

successful, and the methodology for implanting them in

wild fish was improved. The advances made in

ultrasonic telemetry as a result of this work now allow

us to address many outstanding questions. The

technology should be especially useful to track salmon

from the rivers of the inner Bay of Fundy where stocks

have severely declined, and to discover their migration

routes and the location of their feeding grounds which to

date remain unknown.

_____________________________________________________________________________________________

Feasibility of long term intramuscular implantation of archival tags in large

pelagic fishes

Richard Brill, Katherine Cousins, Pelagic Fisheries Research Program, Joint Institute for Marine

and Atmospheric Research, School of Ocean and Earth Science and Technology, University of

Hawaii at Manoa, Honolulu, Hawaii, 96822, U.S.A. Phone: 808-592-8304; FAX:

808-943-1290

Pierre Kleiber, La Jolla Laboratory, Southwest Fisheries Science Center, National Marine

Fisheries Service, La Jolla, California, 92038-0271, U.S.A.

(mailing address: NMFS, 2570 Dole Street, Honolulu, Hawaii, 96822-2396, U.S.A.)

Geographic positions of fish can now be collected

using commercially available electronic archival tags

that measure and store data on ambient light level, fish

depth, and water temperature for up to 12 years.

Although the engineering problems have been

surmounted, viable long term (years) tag attachment

methods remain problematic and in need of careful

testing. This is especially true for pelagic species such

as tunas (Thunnus spp.) and billfishes (Istiophoridae and

Xiphiidae) where large individuals are often difficult to

handle. Archival tags have been successfully implanted

in the peritoneal cavity of southern and northern bluefin

tunas (Thunnus maccoyii and T. thynnus, respectively).

However, tags placed in the peritoneal cavity may be

lost through trans-intestinal or body wall expulsion and

require that fish be removed from the water, restrained

and/or anesthetized during placement. An alternative

approach is intramuscular implantation. We therefore

tested the feasibility of long-term intramuscular

implantation using miniature stainless steel scale model

archival tags and juvenile yellowfin tuna (Thunnus

albacares) held in shore side tanks. Because functional

archival tags are too large to be implanted in the 1-2 kg

fish available for our study, we employed scale model

tags approximately 0.6 cm in diameter, 4 cm long, and

weighing 3.5 g. The model tags were made of the same

316 grade stainless steel as functional archival tags.

They also had a simulated fiber optic light stalk, crafted

from nylon monofilament line encased in Teflon, on

one end. 

Model tags were inserted into the white muscle of

fifteen fish, through a small incision in the skin, at the

anterior edge of the first dorsal fin. In thirteen fish, the

tags were placed with the simulated fiber optic light

stalk either pointing anteriorly or perpendicular to the
Acoustic and Archival Tags: Applications to Salmonid Research 57

dorsal body surface. In the remaining two fish, the tags

were placed with the simulated fiber optic light stalk

pointed caudally. Ten of the fifteen fish survived for

approximately ten months after tagging and of these,

seven had retained their tags. In the fish where the tags

were retained for 10 months, the simulated fiber optic

stalk pointed anteriorly. More important, in no fish

was there any gross evidence of infection or tissue

necrosis around the tag insertion site or where the

simulated fiber optic light stalk exited the skin. There

was also no evidence that any of the seven fish would

lose their tags in the near future. Tag bodies were all

found to be embedded approximately 5 cm below the

 dorsal body surface in spite of the fish increasing in

size from approximately 1-2 kg to a final body mass of

11+ 2 kg (mean + SD). We also found no evidence of

serious chronic inflammation, edema, or major necrosis

around the tag body. Instead, only a thin protective

layer of connective tissue surrounded both the tag body

and the intramuscular portion of the simulated fiber

optic light stalk. Our results therefore demonstrate that

long-term intramuscular implantation of archival tags is

feasible in tunas (and possibly in other pelagic species)

and a viable alternative to intraperitoneal placement or

external attachment.

_____________________________________________________________________________________________

The use of acoustic and data storage tags in establishing the role of 

the tidal streams in plaice migration in the southern North Sea

J.D. Metcalfe & G.P. Arnold. Ministry of Agriculture Fisheries and Food, Directorate of Fisheries

Research, Fisheries Laboratory, Lowestoft, Suffolk, NR33 OHT, UK.

During the 1970’s and 80’s acoustic tracking and

mid-water trawling experiments with plaice

(Pleuronectes platessa L.) in the southern North Sea

established that this species migrates between summer

feeding grounds and winter spawning grounds by

selective tidal stream transport. This behaviour is

characterized by a circatidal pattern of vertical movement

in phase with the tidal streams. The fish leave the sea

bed and move into mid-water at about the time of slack

water and swim down tide for the major part of the

ensuing north-going or south-going tide. As the tide

turns again, the fish return to the sea bed where they

remain for the duration of the opposing tide.

Since late 1993, we have been monitoring the

movements of plaice in the North Sea with new small

electronic data logging tags which record the depth of

the fish every ten minutes, and temperature once each

day, for periods of up to 8 months. When fish are

caught and the tags returned, the patterns of vertical

movement are used to reconstruct the geographical

movement of the fish using a computer simulation

model of the tidal streams. To date, 140 of these tagged

plaice have been released and 20 tags have been returned.

From these over 1500 days of data have been retrieved

revealing seasonal patterns of vertical and spatial

movements.

These data are now yielding detailed information on

the behaviour of free-ranging fish over periods of many

months which should allow us to recognize what, if

any, environmental event stimulates the start of the prespawning migration and how this varies between sexes

and ages of fish. The information will also indicate

how the patterns of vertical movement of individual fish

relate to local tidal and diel cycles allowing us to

identify which environmental clues and cues are

important in controlling vertical movement and,

therefore, which sensory systems underlie the complex

repertoire of behaviours which result in large scale

seasonal migrations.

Further data are needed if we are to understand fully

the migrations of plaice in the North Sea, together with

the interrelationships between the various stocks and

sub-stocks that are thought to exist. We should like

also to extend the work to other parts of the continental

shelf and to other species, such as cod, about which we

already know a little from tracking experiments with

sonar and transponding acoustic tags. To this end we

need cheaper, smaller electronic tag with a longer

recording life, a target that our engineers have recently

achieved with a new tag 56 x 18 mm, 16 g in air (1 g

in water) and with 12 Mbit memory which can store

over 523 000 data samples (light, pressure and

temperature) with a 12 bit resolution. In the longer
58 Acoustic and Archival Tags: Applications to Salmonid Research

term, too, we would wish to significantly increase the

probability of data recovery by developing a pop-up tag

whose data could be recovered by airborne radio or

satellite, techniques that are probably already practical

with large pelagic oceanic species, such as tuna and

swordfish. The planned addition of sensors into our

electronic tags for detecting compass heading will,

 likewise, greatly expand our understanding of the

environmental clues and sensory mechanisms used to

orientate during down-tide swimming, while the

addition of a swimming speed sensor will reveal more

complete information about the energetics of migration

and permit more accurate reconstructions of the

geographical tracks.

_____________________________________________________________________________________________

Temperature and data loggers from Onset Computer Corporation

Mark McSherry. Onset Computer Corporation, 536 MacArthur Blvd., Pocasset, MA 02559-3450

Onset Computer Corporation, has designed and

manufactured low-power data loggers since 1981. We

have over 100,000 loggers in use worldwide and our

largest customer base is the natural resources market,

including a strong following in the fisheries market.

Onset has a company goal of being a market leader in

providing high volume, low cost miniature data

loggers. Generally, we build and stock standard

products although we do accommodate custom product

variations of our standard products ( i.e., changing

temperature ranges, adding external sensors).

Our products are primarily used to measure water

temperature, but we have several customers who have

used our smallest loggers to measure body temperatures

in alligators, turtles, snakes and ground squirrels.

Onset manufactures two single-channel, battery-operated 

temperature loggers which are small. The HOBO

Littler (1.5S long x 0.5S wide x 0.5S thick) takes 1800

measurements over two months and weighs 0.15 oz..

The StowAway Tidbit ( (1.2S wide x 1.S tall x 0.65S

thick) takes 7,944 measurements over two years and

weighs 0.8 oz. Both products can be off loaded to a PC

or Mac using our Logbook software. Data can be

exported to popular spreadsheet programs. 

Onset data loggers incorporate 8 bit

microprocessors and store data on non-volatile

EEPROM memory. This memory ensures that the data

is saved in the event that power is lossed. Accuracy and

resolution curves are available for all Onset data

loggers. More information on Onset single channel

data loggers and multi-channel data logger/controller

engines are available at www.onsetcomp.com.

_____________________________________________________________________________________________

Data Archival and Satellite-linked Tags from Wildlife Computers

Roger Hill, Wildlife Computers, 16150 NE 85th St #226, Redmond, WA 98052, USA. (206)

881-3048, 72012.721@compuserve.com

Wildlife Computers has been producing data

archival tags (TDRs) designed specifically for marine

wildlife research since 1986. The customized packaging

and sensors of our tags have allowed them to be used for

studies of diverse species, including phocids and

otariids, cetaceans, penguins, sea turtles and sharks, as

well as on long-line and trawl fishing gear. Sensors

include depth (ranging from 0-25m tags for Albatross to

0-2000m tags for elephant seals), internal and

environmental temperature, light-level, activity, noise

level, and heartrate. These instruments are designed to

withstand harsh environments, to be small in size, to

have a long deployment life and high memory capacity,

and to be flexible with a variety of user-programmable

parameters.
Acoustic and Archival Tags: Applications to Salmonid Research 59

Our archival tags can be programmed to collect

light-level and environmental temperature readings to be

used for global positioning (geolocation). In 1990, we

developed a system of PC-based programs to process

these collected data to calculate daily latitude and

longitude positioning with an accuracy of

approximately 1°.

Over the years, Wildlife Computers has

incorporated advancements in technology to increase the

 capabilities of our instruments, as well as to reduce the

size and power consumption. The newest data archival

tag has 2Mbytes of non-volatile memory, weighs

approximately 30g, and has a battery life of 10 years.

Wildlife Computers also manufactures satellitelinked time-depth recorders (SDRs) which transmit

collected data to the Service Argos satellite system.

The first SDRs were deployed in December 1989.

_____________________________________________________________________________________________

Acoustic tags available from SONOTRONICS

Marlin J. Gregor, SONOTRONICS, 1130 E. Pennsylvania St., Suite 505, Tucson, AZ 85714

email: mgregor@azstarnet.com

SONOTRONICS has been a manufacturer of

ultrasonic tracking systems for 25 years. These

systems offer particular advantages over RF tracking

under specific conditions. Ultrasonic (often referred to

as just "sonic") systems rely on propagation of sound

waves in water, which is fundamentally a mechanical

rather than electronic process, and operate at frequencies

between 30kHz and 100kHz. As a rule of thumb,

sonics are the most suitable tags in water over 5m in

depth or when conductivity exceed 400umho /cm.

Sonic systems are comprised of hydrophones,

receivers, and tags. Hydrophones are basically sensitive

underwater microphones that are tuned to accept sound

at these high frequencies, and due to the short

wavelengths of ultrasound in water, relatively small

hydrophones can offer excellent directivity: beam widths

of +/- 6 degrees are typical of units the size of a small

tupperware container. Ultrasonic receivers are generally

paired with a particular manufacturer's hydrophone in

order to achieve optimum performance. Typically,

receivers are separated into 2 types: scanning receivers

used for unmanned or automatic systems, and manual

tracking receivers designed to by used by individuals

tracking from shore or on a boat.

Sonic tags are the most variable item of a system,

and usually amount for the majority of the cost. Three

variables define a tag: size, life, and range, and once 2

of these items are selected, the third becomes fixed. 

Size in generally determined by the smallest size

specimen to be tagged: a general guideline states that

the tag weight (measured in water) should not exceed

2% of the body weight (in air) of the fish to be tagged.

Currently, the smallest tag manufactured by

SONOTRONICS measures 8mm x 28mm, with a water

weight of just under 2 grams. Following the above

guideline, this tag should be used on fish of no less

than 100 grams. These tags, when used with

SONOTRONICS' receivers, have a detectable range of

750 to 1000 meters, and consequently have a lifetime of

slightly more than 2 weeks. Although it is likely that

smaller tags will soon be available (40% smaller), this

will result in a shorter useable life (7 - 10 days). On

the other hand, tags with a 4 year life are available with

detection ranges of 1km, but with dimensions of

18mm x 65mm and a water weight of 8 grams. It

should be noted that tags used in studies that will last

more than 3 - 6 months should seriously consider

surgically implanting tags. A free video is available on

request from SONOTRONICS showing a sample

surgical procedure.

Identifying individuals with sonic tags can be

accomplished a couple of ways: bandwidth in the

ultrasonic region is narrow, only 10's of unique

frequencies are available, so unique intervals between

pings may be used with tags of the same frequency to

provide identification. SONOTRONICS also uses a

technique of aural coding provide individual recognition. 
60 Acoustic and Archival Tags: Applications to Salmonid Research

A code such as 2-4-9 would be detected by a person

listening to a receiver as 2 pings, followed by a pause,

followed by 4 pings, another pause, then 9 pings and a

pause before repeating this sequence over again. This

technique allow for literally hundreds of tags to be used

in the same area yet be identified as unique. Finally,

sonic tags may be used to provide parametric data about

the immediate environment where the specimen is

located. Depth or temperature may be telemetered back

to the receiver by changing the interval between

successive pings from a tag, providing realtime

information about the habitat.

_____________________________________________________________________________________________

Zelcon Technic Wildlife Tracking Systems

Ana Nicolau, Zelcon Technic Pty Ltd., Technopark Dowsings Point, Glenorchy TAS 7010,

Australia

Zelcon produces an archival tag known as the “ZT6

Datalogger”. This advanced surface mount technology

is employed in miniature dataloggers that have been

designed for wildlife and environmental studies. The

recording schedule can be designed by the user, with

sampling rates varying from 1 second to 1 year. The

logging life is up to 4 years and the data retention is

over 20 years, independent of the battery life. The tag

has the following characteristics:

Minimum size: 55x24x12mm

Minimum weight: 25 gram

Memory capacity: 1Mbyte of Flash memory.

Sensors: 

Activity sensor, Travel sensor, In-Water sensor

(conductivity), In-Water sensor (ultrasonic)

Pressure sensor (0-500m, resolution 2m)

Pressure sensor (metallic package)

*Other pressure sensors, pressure ranges available

Sensor pad (including external temperature sensor

and light sensor)

Light sensor (on the tag)

Temperature sensor external/internal (-20°C to

+50°C range with 0.15° C resolution standard)

Tail-beat sensor

Humidity

Data format: ASCII

Interface requirements: Adaptor to PC serial port,

4,800 minimal baud rate

Software required: Any Terminal Program (eg

Windows 3.1 Terminal)plus

Data Display/Analysis

Software

The assembly is potted in heat cured epoxy to provide

environmental protection.

Future developments with this tag include reduction

of datalogger’s weight and size (down to 60-70% of the

current parameters) and options in the memory capacity

(512Kbyte, 1 Mbyte, or 2 MByte Non-Volatile

memory). Also under development is ZelLINKTM, a

Pop-Up Satellite transmitting Electronic Datalogger,

which will integrate a datalogger (archival tag) and an

ARGOS Satellite Transmitter to allow the transmission

of data direct to laboratories via the ARGOS System

and ensure an 1:1 data recovery rate.

Also under development is the ZELCODETM

Advanced Telemetry System, which allows for

transmissions of sets of data on only one frequency for a

large number of animals/fish/birds due to unique digital

codes associated with the transmitters. The system is

suitable for monitoring studies of a large number of

individuals. The data -- unique digital code and

optionally temperature, activity, travel information and

other parameters -- are received and sent via RS-232

interface to an IBM compatible computer. The

ZELCODETM system can be easily adapted to transmit

the information via ultrasound. The range, number of

tags required, relevant measurements (eg:temperature,

pressure etc.) for the application are to be determined in

consultation with the end-user.

_____________________________________________________________________________________________
Acoustic and Archival Tags: Applications to Salmonid Research 61

Appendix 2: Workshop Participants

Dr. George Boehlert

NMFS Southwest Fisheries

Science Center

Pacific Fisheries Environmental

Group

1352 Lighthouse Ave.

Pacific Grove, CA 93950-2097

Tel: (408) 648-8447

Fax: (408) 648-8440

e-mail: gboehlert@pfeg.noaa.gov

Ms. Melinda Braun

Wildlife Computers

16150 NE 85th St. #226

Redmond, WA 98052

Tel: (206) 881-3048

Fax: (206) 881-3405

e-mail:

72102.721@compuserve.com

Dr. Ed Casillas

Northwest Fisheries Science Center

NOAA-NMFS, F/NWC1

2725 Montlake Blvd. E.

Seattle, WA 98112-2013

Tel: (206) 860-3313

Fax: (206) 860-3335

e-mail:

ecasillas@sci.nwfsc.noaa.gov

Dr. Mike Dahlberg

NMFS/AFSC

Auke Bay Laboratory

11305 Glacier Hwy.

Juneau, AK 99801-8626

Tel: (907) 789-6002

e-mail:

mdahlberg@abl.afsc.noaa.gov

Mr. Phil Ekstrom

Northwest Marine Technology

P.O. Box 427

Shaw Island, WA 98286

Tel: (360) 468-3375

Fax: (360) 468-3844

e-mail: ekstrom@nmt-inc.com

Dr. Mickey Eldridge

NMFS Tiburon

3150 Paradise Dr.

Tiburon, CA 94920

Tel: (415) 435-3149 x243

Fax: (415) 435-3675

e-mail: mxeldrid@crl.com

Mr. Bob Emmett

NOAA-NMFS, NWFSC

Marine Science Center

Newport, OR 97365

Tel: (541) 867-0109

Fax: (541) 867-0389

e-mail: emmettb@ccmail.orst.edu

Dr. Kevin Friedland

Northeast Fisheries Center

Water Street

Woods Hole, MA 02543

Tel: (508) 495-2369

Fax: (508) 495-2258

e-mail:

kfriedla@whsun1.wh.whoi.edu

Dr. Michael Healey

University Of British Columbia

Fisheries Centre

2204 Main Mall

Vancouver, BC

V6T 1Z4 Canada

Tel: (604) 822-4705

Fax: (604) 822-5357

e-mail: healey@ocgy.ubc.ca

Dr. Jack Helle

NMFS/AFSC

Auke Bay Laboratory

11305 Glacier Hwy.

Juneau, AK 99801-8626

Tel: (907) 789-6038

Fax: (907) 789-6094

e-mail: jhelle@abl.afsc.noaa.gov

Mr. Roger Hill

Wildlife Computers

16150 NE 85th St. #226

Redmond, WA 98052

Tel: (206) 881-3048

Fax: (206) 881-3405

e-mail:

72102.721@compuserve.com

Dr. Jim Ingraham

Alaska Fisheries Science Center

NOAA-NMFS-RACE, F/AKC1

7600 Sand Point Way NE

Seattle, WA 98115-0070

Tel: (206) 526-4241

e-mail:

jim_ingraham@afsc.noaa.gov

Dr. Peter Klimley

Bodega Marine Laboratory

Univ. Of California, Davis

P.O. Box 247

Bodega, CA 94923

Tel: (707) 875-2055

Fax: (707) 875-2089

e-mail: apklimley@ucdavis.edu

Dr. Robert Kope

Northwest Fisheries Science Center

NOAA-NMFS, F/NWC1

2725 Montlake Blvd. E.

Seattle, WA 98112-2013

Tel: (206) 860-3374

e-mail: rkope@sci.nwfsc.noaa.gov

Richard D. Ledgerwood

NMFS-NWFSC

Pt. Adams Lab

Hammond, OR 

Tel: (503) 861-1853

e-mail: dick.ledgerwood@noaa.gov

Dr. Allan Macklin

Pacific Marine Envtl. Lab

NOAA/OAR

7600 Sand Point Way NE

Seattle, WA 98115-0070

e-mail: macklin@pmel.noaa.gov
62 Acoustic and Archival Tags: Applications to Salmonid Research

Dr. Bruce MacFarlane

NMFS Tiburon Laboratory

3150 Paradise Dr.

Tiburon, CA 94920

Tel: (415) 435-3149

Fax: (415) 435-3675

e-mail:

brucem@aurora.tib.nmfs.gov

Dr. Kate Myers

University Of Washington

Fisheries Research Inst., WH-10

Seattle, WA 98195

Tel: (206) 543-1101

Fax: (206) 685-7471

e-mail:

kmyers@fish.washington.edu

Dr. Miki Ogura

Tohoku Natl Fisheries Research

Inst.

3-27-5 Shinhama-Cho 

MIYAGI 985 Shiogama

Japan

Tel: (022) 365-9925

Fax: (022) 367-1250

e-mail: ogura@myg.affrc.go.jp

Dr. Jim Overland

Pacific Marine Envtl. Lab

NOAA/OAR

7600 Sand Point Way NE

Seattle, WA 98115-0070

e-mail: joverlan@pmel.noaa.gov

Dr. William G. Pearcy

Oregon State University

College Of Oceanography

Corvallis, OR 97331

Tel: (541) 737-2601

Fax: (541) 737-3964 lab

e-mail:

wpearcy@neptune.oce.orst.edu

Dr. Thomas Quinn

University Of Washington

Fisheries Research Inst., WH-10

Seattle, WA 98195

Tel: (206) 543-9042

Fax: (206) 685-7471

e-mail:tquinn@fish.washington.edu

Mr. Roberto Racca

Jasco Research, Ltd.

102-7143 West Saanich Road

Brentwood Bay, BC

V8M 1P7 Canada

Tel: (604) 544-1187

Fax: (604) 544-4916

e-mail: rob@jasco.com

Dr. Peter Rand

University Of British Columbia

Fisheries Centre

2204 Main Mall

Vancouver, BC

V6T 1Z4 Canada

Tel: (604) 822-9381

Fax: (604) 822-8934

e-mail: psrand@unixg.ubc.ca

Dr. Jim Schumacher

Pacific Marine Envtl. Lab

NOAA/OAR

7600 Sand Point Way NE

Seattle, WA 98115-0070

Tel: (206) 526-6197

Fax: (206) 526-6485

e-mail: jdschu@pmel.noaa.gov

Dr. Paul Siri

Bodega Marine Laboratory

Univ. Of California, Davis

P.O. Box 247

Bodega, CA 94923

Tel: (707) 875-2211

Fax: (707) 875-2009

e-mail: pasiri@ucdavis.edu

Mr. Keith Stoodley

Lotek Marine Technologies, Inc.

114 Cabot Street

St. John's, NF

A1C 1Z8 Canada

Tel: (709) 726-3899

Fax: (709) 726-5324

e-mail: kstoodley@lotek.com

Dr. Keith A. Thomson

University Of British Columbia

Fisheries Centre

2204 Main Mall

Vancouver, BC

V6T 1Z4 Canada

Tel: (604) 822-3025

Fax: (604) 822-8934

e-mail: keitht@direct.ca

Mr. Fred Voegeli

VEMCO Limited

100 Osprey Drive

Shad Bay, NOVA SCOTIA

B3T 2C1 Canada

Tel: (902) 852-3047

Fax: (902) 852-4000

e-mail: vemco@fox.nstn.ca

Dr. David Welch

Pacific Biological Station

Department Of Fisheries And

Oceans

Nanaimo, BC

V9R 5K6 Canada

Tel: (604) 756-7218

Fax: (604) 756-7333

e-mail: welchd@pbs.dfo.ca