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DEVELOPING A NOMENCLATURE FOR STEELHEAD, COHO, CUTTHROAT AND OTHER ANADROMOUS SALMONIDS WITH EXTENDED FRESHWATER REARING Hal Michael, John McMillan, Bob Gresswell, Leon Shaul, Bob Leland, Joan Trial

Hal Michael, John McMillan, Bob Gresswell, Leon Shaul, Bob Leland, Joan Trial

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DEVELOPING A NOMENCLATURE FOR STEELHEAD, COHO, CUTTHROAT AND OTHER ANADROMOUS SALMONIDS WITH EXTENDED FRESHWATER REARING. Hal Michael, John McMillan, Bob Gresswell, Leon Shaul, Bob Leland, Joan Trial. WHAT AND WHY?. Knowledge of life history “oddities” has advanced but terminology has not - PowerPoint PPT Presentation

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Page 1: Hal  Michael, John McMillan, Bob Gresswell, Leon Shaul, Bob Leland, Joan Trial

DEVELOPING A NOMENCLATURE FOR STEELHEAD, COHO, CUTTHROAT AND

OTHER ANADROMOUS SALMONIDS WITH EXTENDED FRESHWATER REARING

Hal Michael, John McMillan, Bob Gresswell, Leon Shaul, Bob Leland, Joan Trial

Page 2: Hal  Michael, John McMillan, Bob Gresswell, Leon Shaul, Bob Leland, Joan Trial

WHAT AND WHY?

• Knowledge of life history “oddities” has advanced but terminology has not

• What we call a fish, or how their behaviour is described, does not always mesh

• A group is beginning to work to develop a unified nomenclature for these fish

Page 3: Hal  Michael, John McMillan, Bob Gresswell, Leon Shaul, Bob Leland, Joan Trial

A HATCHERY STEELHEAD CAN

1 Smolt as age-1, after stocking

2 Smolt as an age 2 or an age 33 Stay permanently in freshwater4 Die

If it stays in freshwater after stocking it is called a residual

Page 4: Hal  Michael, John McMillan, Bob Gresswell, Leon Shaul, Bob Leland, Joan Trial

A WILD STEELHEAD CAN

1. Smolt as an age 12. Smolt as an age 2 or 3 or 4 or..3. Stay permanently in freshwater4. Die

It has no special name, yet it and the hatchery fish behave in the same manner. Is an age 1+ non-smolted wild mykiss a residual?

Page 5: Hal  Michael, John McMillan, Bob Gresswell, Leon Shaul, Bob Leland, Joan Trial

STRAY, HOME STREAM FIDELITY

• Wild migratory salmonids are believed to have very accurate homing instinct, some few who do not home accurately are said to stray.

• A variety of studies on hatchery origin fish show significantly less accuracy in homing; they are called strays

Page 6: Hal  Michael, John McMillan, Bob Gresswell, Leon Shaul, Bob Leland, Joan Trial

STRAY, HOME STREAM FIDELITY II

• Studies with non-lethal tags have shown some interesting results– A wild steelhead smolts from Stream A and returns to Stream B– A wild steelhead spawns in Stream A and repeat-spawns in Stream

B– A wild steelhead spawns in Streams A&B in the same year

– And the home stream is ???

Page 7: Hal  Michael, John McMillan, Bob Gresswell, Leon Shaul, Bob Leland, Joan Trial

STRAY, HOME STREAM FIDELITYSTRAY III

• Sea-run cutthroat smolt from Stream A and overwinter in Stream B-these are called “Feeders”

• Adult sea-run cutthroat overwinter in Stream A and them move to Stream B to spawn

• Where’s “home?”

Page 8: Hal  Michael, John McMillan, Bob Gresswell, Leon Shaul, Bob Leland, Joan Trial

T                                                                                                                                                                                                 The big unanswered question: Where would it have gone to spawn?

An Alaskan coho: a brood year 1997 coho smolt ---- that originated who-knows-where---- spent the summer of 1998 in marine/estuarine waters, entered the Chilkat with the returning nomad migration in Fall 1998, was caught and CWT’d somewhere 5–26 km up the Chilkat between April 7 and June 2, 1999, re-entered saltwater and swam a minimum 67 km down and across Lynn Canal to the mouth of the Berners River where it joined the fall nomad migration up that system for 8 km to a Beaver Pond from which it was recaptured in a downstream migrant trough trap on May 17, 2000 at fork length of 126 mm. A second tagged Chilkat fish (length 127 mm) was recovered leaving the same pond 9 days later, but it had only been in saltwater during summer 1999, right after tagging, and had lived a “normal” coho existence in its first year. The big unanswered question: Where would it have gone to spawn?

Page 9: Hal  Michael, John McMillan, Bob Gresswell, Leon Shaul, Bob Leland, Joan Trial

STRAY, HOME STREAM FIDELITYSTRAY IV

• Coho that smolt from Stream A and overwinter in Stream B, and maybe C, return to what home stream and what stream would they be a “stray”?

• Currently, these coho are called Nomads

Page 10: Hal  Michael, John McMillan, Bob Gresswell, Leon Shaul, Bob Leland, Joan Trial

SMOLTS

• Everybody knows that salmonids smolt in the spring

• Except for coho and steelhead that also smolt in the fall

Page 11: Hal  Michael, John McMillan, Bob Gresswell, Leon Shaul, Bob Leland, Joan Trial

THE GOAL

Develop a consistent nomenclature for PNW anadromous salmonids,

concentrating on steelhead but recognizing that their life history

patterns may occur in coho, cutthroat, native char, Atlantic salmon, sea trout,

and coasters

Page 12: Hal  Michael, John McMillan, Bob Gresswell, Leon Shaul, Bob Leland, Joan Trial

KELTS

• We call a post-spawning trout a kelt• When I named a post-spawning

lamprey a kelt I was told this applies only to Atlantic salmon

• A “resident” mykiss that spawns and then smolts is a smolt-kelt?

Page 13: Hal  Michael, John McMillan, Bob Gresswell, Leon Shaul, Bob Leland, Joan Trial

IF YOU WANT TO PARTICIPATE

Contact Hal Michael at [email protected]

We will then organize the group, divide up tasks, and move ahead.

Page 14: Hal  Michael, John McMillan, Bob Gresswell, Leon Shaul, Bob Leland, Joan Trial