The View from 60,000 Feet
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The View from 60,000 Feet Evolution and Diversity of Steelhead Ken Currens Pacific Coast Steelhead Management Meeting 2010
description
The View from 60,000 Feet. Evolution and Diversity of Steelhead. Ken Currens Pacific Coast Steelhead Management Meeting 2010. Things weren’t always as they are now. The present is often more interesting if we know something about the past. West Africa, 1930. Eocene North America - PowerPoint PPT Presentation
Transcript of The View from 60,000 Feet
The View
from 60,000 Feet
Evolution and Diversity
of Steelhead
Ken CurrensPacific Coast Steelhead Management Meeting 2010
West Africa, 1930
Things weren’t always as they are now
The present is often more interesting if we know something about the past
Eocene North America 55-30 Million
Years AgoBegan with rapid warming
Tropical forests in Pacific Northwest
Polar climates similar to Pacific Northwest today
Large lakes and inland seas; none of existing mountain ranges
British Columbia40-50 Ma
Salmonidae already present
Eosalmo driftwoodensis
Included• Thymallinae• Coregoninae• Salmoninae
Start of long-term cooling trend
Continued coolingallowed dispersal
southwardLate Miocene (10-5 Ma)
The Sabertooth SalmonOncorhynchyus (Smilodonichthys) rastrosus
Continued coolingallowed dispersal
southward
Plio-Pleistocene (5-0.1 Ma)
Fossil O. australisIn Lake Chapala, Mexico
Distribution of western trouts in North America
about 1900 (from Behnke 1992)
Diversity of extant western trouts
Coastal cutthroat
Westslope cutthroat
Yellowstone cutthroat
Rio Grande cutthroat
Colorado River cutthroat
Greenback cutthroat
Mexican golden trout& undescribed trout
Apache trout
Gila trout
Rainbow trout O. mykiss
Bonneville cutthroat
Humboldt cutthroat
Lahontan cutthroat
Paiute cutthroat
Whitehorse & Alvord cutthroats
California,& Kern golden trouts
Extant distribution does not simply reflect colonization
to the south
Extant distribution does not simply reflect southward
colonization
Formation of mountain ranges
Shaping old rivers & creating new ones
Faulting in Basin & Range
Columbia basalts & Snake River flows
Volcanic lava floods
Glaciation
Extant distribution does not simply reflect colonization
to the south
Extant distribution does not simply reflect southward
colonization
Formation of mountain ranges
Shaping old rivers & creating new ones
Faulting in Basin & Range
Columbia basalts & Snake River flows
Volcanic lava floods
Glaciation
No O. mykiss in the Columbia River as recently as 70,000-
50,000 years ago
Extant distribution does not simply reflect colonization
to the south
Extant distribution does not simply reflect southward
colonization
Eoc
ene
Mio
cene
Olig
ocen
ePleistocene
Pliocene
23
5.3
34
2.6
Species & Subpecies of North American trout
HuchoBrachymystaxSalvelinus
OncorhynchusSalmo
Salmo Oncorhynchus
Two Morphologically Different Forms of
Steelhead Trout
Inland or fine-scale form with redband trout-like characteristics
Coastal form
Landlocked “redband” trout with cutthroat-like characteristics (Oncorhynchus sp.)
Extant distribution does not simply reflect colonization
to the south
Coastal & Inland forms thought to reflect dispersal after isolation & differentiation in glacial refuges
Mexican golden trout& undescribed trout
Most primitive forms of O. mykiss occur near
Gulf of California
Primitive Traits
Derived Traits
California & Kern golden trouts
McCloud redband
Upper Klamath redband
Goose Lake, Warner,& Chewaucan redbands
Fort Rock redband
Catlow Valley redband
Columbia River redbands
Coastal rainbow trout & steelhead
White River redband
Earliest O. mykiss evolved around the Gulf of California &
dispersed north
Gulf of California
Sacramento
San Joaquin
Klamath
?Columbia
Oregon Desert Basins
Reached Columbia River 32-50K years ago
Gulf of California
Sacramento
San Joaquin
Klamath
?Columbia
Oregon Desert Basins
Tahoe Glaciation 32K years ago
Glacial Lake Missoula
Upper Fraser
Puget Sound
10-15 K years ago
C CCCCBB B
G
G
EG
B
EEE
BBBA
A
B
C
AAAAEFFFFFFF
AAAA
CBBCBF
AAA
ADDDDGGGGBBBBBB
CAAA
A AAABB
BBBBB
CE
BBBA
AAA
CB
G
Columbia River
C C
Ca
non
ica
l Va
ria
te II
I
K
H
H
IHH
K
HIntermediates?Harney (H), Catlow (I)Fort Rock (K)
N
NMN
M
NN
NQ
Q
MM
M
M
M
M
MMMM
M
MN N
NNN N
Klamath:Upper Klamath headwater (M), Upper Klamath Lake (N)Coastal Klamath mountains (Q)
-30 -20-25 5-15 -10 -5 0
-10
-5
0
5
-15
Canonical Variate I
L
L
L
J
J
JJJ
OO O
OO
Sacramento:Goose Lake (L), Warner Lakes (O)Chewaucan (J)
L
Sacramento
San Joaquin
Klamath
?Columbia
Oregon Desert Basins
Glacial Lake Missoula
Upper FraserPuget
Sound
Steelhead life-history contributed to greater O. mykiss diversity
than often recognized
Sacramento
San Joaquin
Klamath
?Columbia
Oregon Desert Basins
Glacial Lake Missoula
Upper FraserPuget
Sound
Large river systems were more important that glaciation in
diversity of O. mykiss
Glacial refuges & dispersal
Persistence in large river systems
37%
67%
Ability to Explain Differences
Sacramento
San Joaquin
Klamath
?Columbia
Oregon Desert Basins
Glacial Lake Missoula
Upper FraserPuget
Sound
Basins now isolated from large river systems played key roles in
the evolution of steelhead
Fishing for Ancestral Steelhead in the Oregon Desert Basins, 1985
Things weren’t always as they are now
The present is often more interesting if we know something about the past
