Northern Pike Population Dynamics in the Upper Colorado River Basin, 20042007

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Northern Pike Population Dynamics in the Upper
Colorado River Basin, 2004-2007 Sam T. Finney
(FWS) Lori Martin (CDOW) John Hawkins (CSU-LFL)
Trina Hedrick (UDWR) Leisa Monroe (UDWR) Kevin
Bestgen (CSU-LFL) Mark Fuller (FWS) Billy
Atkinson (CDOW)
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Presentation Format ? Timeline, map, overview
and basic statistics (CPUE, abundance, etc.) of
main study areas (98 a,b,c, and Middle Green) ?
Other Reaches that Contain Pike ? Source
Populations ? Summary Slides ? Length Data ?
Movement ? Comments and Consensus
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(No Transcript)
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Timeline (Melissa's Slide)
These data are a snapshot in time
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98c (Steamboat to Hayden) 29 miles Elk River is
a major tributary Habitat varies by reach
(Backwaters/Sloughs, Steamboat, Elk R.) Habitat
work is underway Sampled in 2004 and 2005
(Mark-Recapture only)
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98c (Steamboat to Hayden) Abundance 2004- 616
(560-691) or 21.7 NP/mile 2005- 722 (509-935) or
25.4 NP/mile Capture Probability- 0.43 CPUE
2004- 7.79 NP/h 2005- 6.68 NP/h Number Tagged
2004- 442 2005- 303
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98b (Hayden to Craig) 39 miles Elkhead Creek is
a tributary in this reach Nursery area Intensive
removal from 2004-2007 (limited removal
previously)
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98b (Hayden to Craig) Abundance (Adult) 2004-
1755 (1289-2221) or 47 NP/mile 2005- 1748
(432-3064) or 47 NP/mile 2006- 717 (338-839) or
19.4 NP/mile 2007- 1608 (572-2643) or 43.6 NP/mile
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98b (Hayden to Craig) Capture Probability
0.08-0.18 CPUE 2004- 7.96 2005- 7.57 2006-
4.32 2007- 5.10
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98a (Middle Yampa) 76 miles Very little
reproduction Little Snake is a tributary Intensive
removal from 2004-2007 Colorado pikeminnow
critical habitat
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98a (Middle Yampa) Abundance (Adult) 2004-
981 (774-1288) or 12.86 NP/mile 2005- 678
(555-861) or 8.89 NP/mile 2006- 623 (517-760) or
8.17 NP/mile 2007- 1073 (825-1321) or 14.1
NP/mile
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98a (Middle Yampa) Capture Probability
0.23 CPUE 2004- 2.15 NP/h 2005- 1.52
NP/h 2006- 0.65 NP/h 2007- 1.38 NP/h
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Middle Green Tagged 1997-2001 Removed
2001-2007 No Abundance Estimates Electrofishing
and Fyke Nets Drastic Declines in CPUE since
2001 Few small fish captured
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Middle Green CPUE (Electrofishing/Fyke
Nets)- 2004 (0.2 NP-h / 0.15NP-d) 2005 (0.6
NP-h / 0.05NP-d) 2006 (0.3 NP-h /
0.04NP-d) 2007 (0.0 NP-h / 0.36NP-d) Number
Removed 200418 2005 29 2006 3 2007 4
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• OTHER AREAS
• ? Browns Park-NP first detected in 2005, All
  age-0 fish evidence of reproduction
• ? Lodore- 2002-200642 NP 191-825mm TL Pike
  were captured in the lower sections near the
  confluence
• ? Split/Whirlpool-13 captured 2004-2007 one
  from Catamount
• ? Duchesne-None captured 2004-2007 previously
  captured

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OTHER AREAS ? Little Snake-None observed not
recently sampled ? Cross Mountain-Ancillary
captures ? Yampa Canyon-45 captured 2004-2007 ?
Gunnison-A few a year ? Colorado-A few a year ?
White-None captured 2004-2007
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Source Populations ? Old Charley Wash 2-3
thousand (2001) ? Catamount Reservoir Ongoing
removal ? Elkhead Reservoir ? Off-channel
wetlands sampled ? Loudy Simpson / SWA
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Summary Thus Far ? Areas of concern for source
populations ? Pike concentrations are low in much
of the basin ? Pike concentrations are high in
the Yampa River and increase in number as you
move upstream
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Mean Northern Pike Density (NP/Mile)
11.00 39.25 23.55
Pooled data for all pike 2004-2007
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Mean Northern Pike Catch Per Effort (NP/h)
1.43 6.24 7.24
Pooled data for all pike 2004-2007
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Mean Northern Pike Removed NP/ Mile / Year
4.39 (1339) 17.90 (2792) 0 Total Number
Removed in Parentheses
Pooled data for all pike 2004-2007
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Length Data Summary ? Their was an influx of
small fish into 98a in 2006 and 2007 ? More
small fish are present as you move upstream ?
Few small pike in other areas of the basin
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NPK Movement Data 2004-2007

• Movement-Within Studies, Among Studies
• Direction-Upstream, Downstream, Within/Among
• Time-Within Years, Among Years, Within/Among
• Distance-Within Years, Among Years, Within/Among
• Age Classes of Fish that Moved
• Growth of Fish Between Movements

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2004 OF FOREIGN TAG RECAPTURES (TOTAL, FROM
UP., FROM DN.)
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2005 OF FOREIGN TAG RECAPTURES (TOTAL, FROM
UP., FROM DN.)
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2006 OF FOREIGN TAG RECAPTURES (TOTAL, FROM
UP., FROM DN.)
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2007 OF FOREIGN TAG RECAPTURES (TOTAL, FROM
UP., FROM DN.)
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NPK Escapement and Reproduction

• Catamount Reservoir-Escapement/Reproduction
• -First in 2006 (Yampa) by Finney and Martin
  (Yampa-critical habitat)
• -First in 2007 (Green-critical habitat) by
  Bestgen
• Yampa SWA ponds-Escapement, Reproduction ??
• - 4 total
• -2 translocated Spring 2005, recaptured in
  river Spring 2006
• -2 translocated Spring 2007, recaptured in
  river Spring 2007
• Loudy Simpson ponds-Escapement, Reproduction ??
• - 1 total
• -translocated in May 2005, recaptured in river
  June 2005

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Big Picture Thoughts

• Number of NPK Moving
• -Minimum of 235, tagged NPK moved among studies
  from 2004 2007
• -What is the proportion of this relative to
  total of fish marked ??

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Big Picture Thoughts

• Distance NPK Travel and Time of Travel
• -NPK travel long distances
• -Catamount to Lodore (205 river miles)
• -NPK are stationary, not moving within years
  and/or among years
• -NPK can travel long distances in relatively
  short time frame
• -1 NPK (961mm) moved 91 river miles in 2 weeks
• -Same NPK moved an additional 55 river miles
  in 3 months
• -NPK can travel long distances over greater
  time frame (1 to 3 years)

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Big Picture Thoughts

• NPK Movement Direction
• -NPK predominantly move in a downstream
  direction
• -206 of 235 (88) moved in a downstream
  direction
• -NPK movement into critical habitat from
  outside of critical habitat
• -of 125 fish that moved among studies in
  critical habitat of the Yampa/Green, 113 (90)
  originated outside of critical habitat

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Big Picture Thoughts

• Size of NPK that Moved
• -NPK varied in size and distance traveled
• -1 NPK (240mm) moved 58 river miles in 2 months
• -1 NPK (1067mm) moved 47 river miles in 1 month
• -NPK moving into Middle Yampa range 240-1067mm
• -NPK moving into Lower Yampa/Yampa Canyon range
  660-715mm
• -NPK moving into Upper Green/Lodore range
  694-962mm
• -NPK moving into Middle Green range 720-826mm

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Big Picture Thoughts

• Escapement from Catamount, Yampa SWA ponds, and
  Loudy Simpson ponds
• Reproduction in Catamount, what about SWA ponds
  and LS ponds??

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Questions-Thoughts-Consensus Are we doing any
good and how? Do we change? ? There is a change
in size structure ? Lack of change in population
size Is their a more efficient approach? ?
Reallocate effort ? More effort Can you
manage/affect a population by attacking at a
certain point? (Valdez) ? There is promise in
certain areas ? Do we move upstream?