larval fish of the lower niagara river betsy trometer, dimitry gorsky, shana chapman and eric snyder...
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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
Niagara Falls
Lewiston
Ft. Niagara
Ontario, Canada
Whirlpool
Art Park
Devil’s hole
Peggy’s Eddy
Stella Niagara
Niagara Falls
Niagara-on-the-lake
Passive Sampling Gear
Drift net
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
Active Sampling GearSurface Trawl
Bottom Trawl
Ichthyoplankton Net
Larval Seine
• 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 • wadeable • walk // to shore• 10 meter section
Sampling EffortYear 2010 2011 2012
Sampling Gear Sampling Dates
No. of Sets
Sampling Dates
No. of Sets
Sampling Dates
No. of Sets
Drift Net 5/19 5 4/27-6/14 15 3/7-5/9 45
Ichthyoplankton Net 5/20 2 6/13-8/19 14 3/13-4/26 23
Larval Seine 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, 8/24
15 6/15 6 N/A N/A
Drift Net
Ichthyoplankton Net
Larval Seine
Light Trap
YOY and Larval fish Catch by GearYear 2010 2011 2012
Sampling Gear No. of Fish
CPU Fish/set
No. of Fish
CPU Fish/set
No. of Fish
CPU Fish/set
Drift Net 0 0 32 2.13 12 0.22
Ichthyoplankton Net
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
* All YOY fish (other collections are a combination of larval fish and YOY)
Family (# species) 2010 2011 2012Silverside (1) 63
Sucker (3) 233 Sunfish (3) 17 43 Herring (1) 140 Minnow (5) 206
Pike (1) 1 Killifish (1) 1 Goby (1) 13 23
Bullhead & Catfish (1) 1 Gar (1) 1
Smelt (1) 2 Perch (2) 6
Trout and Salmon (2)* 27 19Unknown 12
Major Taxonomic Groups
Gear SelectivityGear
Famiily/SppDrift net
Ichthyoplankton netLarval seine
Light Trap
Surface Trawl
Bottom Trawl
Brook silverside XX Sucker Family XX X Rock Bass X XX XX XLargemouth Bass X X Smallmouth Bass XX XX Alewife XX X Minnow Species XX XX Bluntnose Minnow X Common Carp X Common Shiner X Emerald Shiner X X X Hornyhead Chub X Northern Pike X Banded Killifish X Round Goby X X XX Brown Bullhead X Longnose Gar X Rainbow Smelt X X Darter spp. X X Yellow Perch X Lake Trout XX X
Species/Family March April May June July AugustBrook Silverside 59 4Sucker Family 232 Rock Bass 1 4 17Largemouth Bass 3 Smallmouth Bass 32 3Alewife 138 1 1Minnow species 76 1Bluntnose Minnow 1Common Carp 1 Common Shiner 4Emerald Shiner 3 5 12Esocidae 1 Banded Killifish 1Round Goby 31 5Brown Bullhead 1Longnose Gar 1 Rainbow Smelt 1 1Darter spp. 2 1Yellow Perch 3 Lake Trout (1 Coregonid)* 8 6 27
Catch by Month
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
Drift net
Larval Seine Surface Trawl
Light Trap
Minnow Trap
Bottom Trawl
Ichthyoplankton Net
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X
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