NR AOC larval fish

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Larval Fish of the Lower Niagara
River
Betsy Trometer, Dimitry Gorsky, Shana
Chapman and Eric Snyder
USFWS
Lower Great Lakes Fish and Wildlife
Conservation Office
Niagara River Fish Community
• Great Lakes Restoration Initiative – Lake Trout
and Lake Sturgeon - since 2010
• Our interest in Lower Niagara River
– Remnant sturgeon population
– Large number of lake trout in river in fall likely
spawning
• May spawn in river, but not confirmed
• Recent surveys identified 60 species
• Support concurrent studies
Objective
• Describe the
composition and
distribution of larval
fish in the lower
Niagara River.
• Sampled in 2010,
2011 and 2012
• In 2012, focused
sampling for Lake
Trout
Lake Ontario
Ft. Niagara
Niagara-on-thelake
Peggy’s Eddy
Stella Niagara
Ontario,
Canada
Lewiston
Art Park
Devil’s hole
Whirlpool
Niagara Falls
Niagara Falls
Passive Sampling Gear
Light Trap
Minnow Trap
•
•
•
•
Stationary
Overnight sets - approx. 24 hrs
Light trap floats at surface
Minnow trap and drift nets on
bottom
• Set in slow moving water
Drift net
Active Sampling Gear
• Pulled through water
• Slower moving water, eddies
• Surface and Bottom Trawls
• Tow 10-15 minutes with
boat, with flow
• Ichthyoplankton net
• Tow midwater with boat
• Set overnight
Larval Seine
• Larval seine
• wadeable
• walk // to shore
• 10 meter section
Surface Trawl
Ichthyoplankton Net
Bottom
Trawl
Sampling Effort
Year
2010
2011
Sampling Gear
Sampling
Dates
No. of Sampling
Sets
Dates
Drift Net
5/19
5
Ichthyoplankton Net 5/20
Larval Seine
2012
No. of
Sets
Sampling
Dates
No. of
Sets
4/27-6/14 15
3/7-5/9
45
2
6/13-8/19 14
3/13-4/26 23
N/A
N/A
6/30-8/11 28
4/25
6
Light Trap
7/2, 8/13
11
5/17-8/5
82
N/A
N/A
Minnow Trap
6/11, 7/2
6
N/A
N/A
N/A
N/A
Surface Trawl
N/A
N/A
6/15, 9/2
5
N/A
N/A
Bottom Trawl
6/8, 7/16, 15
8/24
6/15
6
N/A
N/A
Drift Net
Ichthyoplankton Net
Larval Seine
Light Trap
YOY and Larval fish Catch by Gear
Year
2010
Sampling Gear
No. of
CPU
No. of
Fish Fish/set Fish
32
0
0
Drift Net
2011
2012
CPU
No. of
Fish/set Fish
2.13
12
CPU
Fish/set
0.22
0
0
18
1.29
2
0.09
Larval Seine
N/A
N/A
554
19.79
0
0
Light Trap
25
2.27
51
0.62
N/A
N/A
Minnow Trap
0
0
N/A
N/A
N/A
N/A
Surface Trawl
N/A
N/A
1*
0.2
N/A
N/A
Bottom Trawl
8*
0.53
0
0
N/A
N/A
Ichthyoplankton
Net
* All YOY fish (other collections are a combination of larval fish and YOY)
Major Taxonomic Groups
Family (# species)
Silverside (1)
Sucker (3)
Sunfish (3)
Herring (1)
Minnow (5)
Pike (1)
Killifish (1)
Goby (1)
Bullhead & Catfish (1)
Gar (1)
Smelt (1)
Perch (2)
Trout and Salmon (2)*
Unknown
2010
17
13
2011
63
233
43
140
206
1
1
23
1
1
2
6
27
12
2012
19
Gear Selectivity
Gear
Famiily/Spp
Brook silverside
Sucker Family
Rock Bass
Largemouth Bass
Smallmouth Bass
Alewife
Minnow Species
Bluntnose Minnow
Common Carp
Common Shiner
Emerald Shiner
Hornyhead Chub
Northern Pike
Banded Killifish
Round Goby
Brown Bullhead
Longnose Gar
Rainbow Smelt
Darter spp.
Yellow Perch
Lake Trout
Drift
net
Ichthyoplankton net
X
Larval
seine
XX
XX
XX
X
XX
XX
XX
Light
Trap
X
XX
X
XX
XX
X
X
X
X
X
X
X
XX
X
X
X
X
X
X
X
X
XX
X
X
Bottom
Trawl
X
X
X
X
Surface
Trawl
Catch by Month
Species/Family
Brook Silverside
Sucker Family
Rock Bass
Largemouth Bass
Smallmouth Bass
Alewife
Minnow species
Bluntnose Minnow
Common Carp
Common Shiner
Emerald Shiner
Esocidae
Banded Killifish
Round Goby
Brown Bullhead
Longnose Gar
Rainbow Smelt
Darter spp.
Yellow Perch
Lake Trout (1 Coregonid)*
March
April
May
June
1
138
July
59
232
4
3
32
1
76
August
4
17
3
1
1
1
1
3
5
1
31
4
12
1
5
1
1
1
2
3
8
6
27
1
1
Conclusions
•
•
•
•
24 species were identified
Larval seine collected most species
All gear had some limitations
Lake trout larval and eggs collected
were confirmed with genetic analysis
• Confirmed lake trout spawn along Art
Park shoreline and upstream of
Devil’s Hole
Sampling Gear
X
Larval Seine
Light Trap
X
Minnow Trap
Surface Trawl
Ichthyoplankton Net
Bottom Trawl
X
Drift net
X
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