Spawning bed installation - Rideau Valley Conservation Authority

A partnership
between:
Otty Lake Fish Habitat
Enhancement Project
Prepared by Jennifer Lamoureux, Aquatic and Fish Habitat Biologist, RVCA
• RVCA staff and Wally Robins an Otty Lake representative conducted site
visits in the spring of 2013/2014 to observe bass during the spawning and
nursery time period to confirm and prioritize fish habitat enhancement
opportunities for Otty Lake.
• Potential locations were mapped by RVCA staff and design options were
researched.
• Phase I work was located on the North end of Otty Lake in 2013.
• Phase II work was focused on the central part of the lake in 2014.
• This is the first time in Eastern Ontario, at this scale, that a smallmouth bass
enhancement project has been designed and implemented.
 The smallmouth bass spawns in late spring and early summer.
 The male builds a nest in 1 to 5 meters of water on sandy, gravel or
rock bottoms of lakes and streams near protection of boulders and logs.
 After spawning the male guards the nest and fans the eggs for
approximately 4 to 10 days until they hatch.
 The female moves out into deeper water to find food and shelter.
 The young are guarded by the male for several weeks and then begin
to leave the nest.
Project Elements for Phase I and II included the following:
 Spawning bed installation (2013 and 2014)
 Sunken wood installation (2013 and 2014)
 Corner stone installation at nests (2014)
Gravel Bed Installation
•an increased number of suitable spawning beds for smallmouth bass over
existing conditions.
•Improve egg development by providing more suitable substrate
•improved substrate conditions for benthic invertebrate populations which
are an important food source for bass.
Sunken Wood Installation
•Provide complex habitat in areas that are adjacent to spawning habitats for
smallmouth to recover from spawning.
•Provide feeding areas for adult fish as smaller fish will populate the wood
complexes.
Cornerstone Installation
 A large boulder at a nest to provide protection from predators
 A visual barrier between bass nests to improve success of spawning and
nursery habitat
Gravel Bed Installation (nesting beds)
 Gravel bed installation in water depths between 1 to 5m in depth.
 Round river wash stone sized 1-2.5 inches in diameter
 Dimensions of each spawning bed were approximately 1 X 1
meters with a thickness of approximately 10cm.
 Nesting sites were spread out a minimum of 30 feet.
 Installation was from a pontoon boat by dumping two pails of
stone for each nest over the side at the desired location.
Sunken Wood Installation (cover)
 Large tree branches and Christmas
trees approximately 6 ft in height
were cemented into 2 gallon plastic
flower pots.
 The plastic flowers pots were
removed prior to installation.
 Installation was from a boat and
pontoon boat by dumping the trees
over the side at the desired location
and depth of 17 to 22 feet.
Cornerstone Installation in 2014
 Large boulders were installed
at spawning beds to provide
cover/protection at installed
nests
 The large boulder also acts as
a visual barrier between nests
as spawning males may build
nests in close proximity
Total Cost Summary
Phase I (2013)
Phase II (2014)
Materials/Services
$2,240
$2,200
Volunteer Time
$2,240
$2,240
RVCA Staff Time
(planning/design/implementation/
monitoring)
$9,800
$5,500
Total Value
$14,280
$9,940
Project Achievements Phase I and II
175 bass nests installed
240 Volunteer Hours
335 Branches and Christmas Tree clusters installed
Day 1 – Sunken Wood Preparation
Day 2 – Wood/Spawning Bed Installations
Spring Monitoring of Bass Nests 2014
 Site visits were conducted on May 26th and June 5th
 Nesting behavior was evaluated on each of these dates
 Observations were made for each spawning bed to determine the status
(confirmed, unconfirmed, possible)
 Nesting material integrity was assessed
Spring Monitoring 2014 Results (Phase I) 92 bass nests
Spawning Bed Status
Numbers
Confirmed (observed male guarding nest)
38
Possible (nest was maintained - cleaned)
5
Unconfirmed (could not see beds due to depths and wave energy)
49
Success rate for confirmed spawning beds
41%
Spring Monitoring of Bass Nests Photos
Spring Monitoring of Bass Nests Photos
Spring Monitoring of Bass Nests 2015
 Site visits were conducted on May 29th and June 3rd
 Nesting behavior was evaluated on each of these dates
 Observations were made for each spawning bed to determine the status
(confirmed, unconfirmed, possible)
 Nesting material integrity was assessed
Spring Monitoring 2015 Results (Phase I and II) 175 nests
Spawning Bed Status
Numbers
Confirmed (observed male guarding nest)
75
Possible (nest was maintained - cleaned)
16
Not Active
27
Unconfirmed (could not see beds due to depths and wave energy)
57
Success rate for confirmed spawning beds
43%
Spring Monitoring of Bass Nests Photos
Spring Monitoring of Black Fry Stage
FUTURE WORK ?
The Otty Lake Association Board voted to
support three more years of habitat restoration
projects on the lake.
Creative plans are under development now!
Phase III Volunteers Required
Contact [email protected]
613-692-3571 ext. 1108 or Wally Robins from
the Otty Lake Association if interested
Thank
you