Tagging and Marking

• Lecture Outline

– Information gained from tagging

– Considerations

– Types of marks and tags and their pros and cons

• Assignments

– Telemetry; pp. 555 - 624 in Fisheries Techniques

Information obtained from tagging studies

1) Fish identification

a) Individuals or populations

2) Movement patterns

3) Population statistics

4) Growth estimates

Considerations for a tagging or marking study

1) Application effort

2) Retention time of tag or mark

3) Ability to detect

4) Effects on fish growth or behavior

5) Cost

6) Ability to differentiate individuals

Assumptions of tagging

1) Tagged fish are recognized and reported

2) Tags do not affect fish behavior, growth, mortality, etc.

Types of marks and tags

External marks

1) Fin clips

2) Branding

3) Paint, stains or dye

External marks: pros and cons

External tags

1) Dangling tags

a) Anchor tags

b) Carlin tags

2) Plate tags

a) Peterson disk

3) Ribbon or thread

a) Spaghetti

External tags: pros and cons

Internal Tags

1) Coded wire tag

2) PIT tags

3) Visual Implant tags

a) Alpha-numeric Code

b) Elastomere

Internal tags: pros and cons

Natural marks

1) Genetic sequence or allele frequency

2) Parasites

3) Isotope signature

4) Natural elements

5) Morphometerics and meristics

Natrual markers: pros and cons

Internal-external mark

1) Chemical

a) Tetracycline or Calcein

2) Thermal mark

a) Leave mark on otolith or scale

3) Elastomers

Internal-external marks: pros and cons