Millard Creek Rearing Channel Fish Habitat & Channel Productivity Report 2018

REPORT PREPARED BY

Esther Guimond, RPBio, Courtenay, BC

and

Wendy Kotilla, RNSDip., Youth and Ecological Restoration, Courtenay, BC

November 2018

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Contents

Contents ........................................................................................................................................................ ii

Figures ........................................................................................................................................................... ii

Tables ........................................................................................................................................................... iii

Photos .......................................................................................................................................................... iii

Acknowledgements ..................................................................................................................................... iiv

Introduction .................................................................................................................................................. 1

Study Location ............................................................................................................................................... 2

Methods ........................................................................................................................................................ 3

Water Quality ............................................................................................................................................ 3

Stream Discharge ...................................................................................................................................... 3

Juvenile Population Estimate .................................................................................................................... 4

Results and Discussion .................................................................................................................................. 5

Water Quality ............................................................................................................................................ 5

Stream Discharge ...................................................................................................................................... 6

Juvenile Rearing ........................................................................................................................................ 8

Habitat Attributes ................................................................................................................................... 11

Juvenile Population Estimate .................................................................................................................. 12

Community outreach .................................................................................................................................. 13

Recommendations ...................................................................................................................................... 14

Summary ..................................................................................................................................................... 14

References .................................................................................................................................................. 15

Appendix 1. Fish captures in the upper Millard Creek rearing channel August 22-24, 2018. .................... 16

Appendix 2. Coho salmon captures in the lower Millard Creek rearing channel August 22-23, 2018

(conducted concurrently by MPWS volunteers). ........................................................................................ 18

Figures

Figure 1. Location of the juvenile rearing survey and Gee trapping locations in the Millard Creek rearing

channel, 22-24 August 2018. ........................................................................................................................ 2

Figure 2. Length frequency histograms for coho salmon and cutthroat trout captured in the Millard

Creek rearing channel, 23-24 August 2018. ................................................................................................ 10

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Tables

Table 1. Water quality measurements in the Millard Creek rearing channel – August 22-24, 2018. Results

from previous surveys for comparison (Moul and Kotilla 2012). ................................................................. 6

Table 2. Stream discharge calculations in the Millard Creek rearing channel, and Millard Creek mainstem,

using a floating object method. .................................................................................................................... 7

Table 3. Comparison of average discharge in the Millard Creek rearing channel in the 4 years of surveys.

Discharge data from 2008-2012 reported in Moul and Kotilla 2012. ........................................................... 8

Table 4. Results from Gee-trap mark-recapture survey in the Millard Creek rearing channel from 22-24

August. .......................................................................................................................................................... 8

Table 5. Comparison of fish sampling statistics in the Millard Creek rearing channel, 2008-2018. ............. 9

Table 6. Summary of habitat measurements at Gee trap locations in the rearing channel, August 23,

2018. ........................................................................................................................................................... 11

Table 7. Catch per unit effort (CPUE) for coho and cutthroat in the Millard Creek rearing channel, 2011-

2018. ........................................................................................................................................................... 12

Table 8. Comparison of population estimates in the Millard Creek rearing channel. ................................ 13

Photos

Photo (cover). Heidi Morfitt shows tour participants a coho salmon smolt.

Photo 1. YERII team: Isa Faria, Graham Hilliar, Heidi Morfitt, Esther Guimond, Wendy Kotilla. ................ iv

Photo 2. Conducting stream discharge and water quality measurements. ................................................. 3

Photo 3. Setting up stop nets for the marked recapture study. ................................................................... 5

Photo 4. Sampling juvenile fish populations in Millard Creek rearing channel. ......................................... 10

Photo 5. Isa Faria and Heidi Morfitt co-facilitate a public tour of the YERII study ..................................... 13

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Acknowledgements

Ministry of Children and Family Development provided funding for Wendy Kotilla and

Graham Hilliar, as well as two youth, Isa Faria and Heidi Morfitt. Millard Piercy Watershed

Stewards contributed funds for Registered Professional Biologist, Esther Guimond.

Private property access to conduct the fish habitat and channel productivity on Millard

Creek Rearing Channel was given by landowners Cheryl and James Glennie, and Dylan Hardie.

We respectfully acknowledge that we conducted this work on the unceded traditional territory of

K’omoks First Nations.

Photo 1. YERII team: Isa Faria, Graham Hilliar, Heidi Morfitt, Esther Guimond, Wendy Kotilla.

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Introduction

The purpose of the Youth and Ecological Restoration, Phase II (YERII) project in the

Millard Creek rearing channel was to:

1. Provide vulnerable youth with work experience and support while conducting

scientific research in the natural ecosystem.

2. Complete a fisheries and habitat assessment of the Millard Creek rearing channel.

This study was conducted to assess Millard Creek rearing channel fish productivity and

stream habitat. It was done in partnership with Millard Piercy Watershed Stewards (MPWS) and

Youth and Ecological Restoration (YER). The rearing channel has had three previous fish

assessment reports in 2012, 2011 and 2008, which are available at

http://youthecology.ca/ecological-reports/.

Millard Creek rearing channel was constructed about 1996 (Moul and Kotilla, 2012). In the

past, the intake valve has had issues with being filled with gravel, which has resulted in lower

stream flows to the rearing channel. In early 2018, the intake valve was again plugged with

gravel, which was emptied with some effort using a high pressure pump. Lower rearing channel

flows have resulted in some concerns about fish productivity.

For this 2018 study MPWS and YER formed the fourth partnership to involve vulnerable

youth with fisheries research in the rearing channel. This was a YER, Phase II project that

involved three adults working with two youth: Biologist, Esther Guimond; YER Coordinator,

Wendy Kotilla; YER Contractor, Graham Hilliar; and two youth, Isa Faria and Heidi Morfitt.

YER is a program that involves vulnerable youth aged twelve to eighteen with community

members to restore Comox Valley watersheds. It provides youth with work experience through

ecological restoration methods, ecotherapy practices and mentoring support. In YERI, youth

work one-on-one with the YER Coordinator and several different environmental groups. In

YERII, youth work with an environmental professional on a specific project for advanced

learning about ecology, research and communication (YER 2018).

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YERII has a five day format, consisting of three days of research and two days for

preparation and delivery of a public tour, which is co-facilitated by the two youth on the final

day. This YERII project was conducted from August 22nd to 26th, 2018.

Study Location

Millard Creek originates from springs and wetlands near Cumberland Road, and flows for

approximately 4.2 km into the east side of the K’omoks Estuary. It is a low gradient stream with

dependable year-round flow. The juvenile rearing survey was located in the upper portion of the

Millard Creek rearing channel (Figure1).

Figure 1. Location of the juvenile rearing survey and Gee trapping locations in the Millard Creek rearing channel, 22-24 August 2018.

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Methods

Water Quality

Environmental and water quality variables measured included water and air temperature,

dissolved oxygen, pH, total dissolved solids and conductivity. Water quality indicators were

measured using a HANNA Instruments HI98129 pH/EC/TDS/Temperature with Only One

Tester, and an OxyGuard Handy Beta Portable DO Meter H01B at the upstream end of the

rearing channel. Water quality was measured just upstream of the discharge sampling site, where

the intake valve discharges into the rearing channel (Figure 1).

Photo 2. Conducting stream discharge and water quality measurements.

Stream Discharge

Stream discharge is a function of water volume and velocity, and was measured using the

floating object method, as described in the Streamkeepers Handbook (Taccogna and Munro

1995). A 5 m length of channel with suitable laminar flow was marked with flagging tape. This

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was the same location used in previous surveys in the rearing channel and was located

approximately 2 m downstream of the rearing channel inlet valve and the water quality sampling

site (Figure 1). A cross sectional area was measured at both the start and finish of the 5m channel

using a measuring tape and meter stick. The cross sectional area of the stream is the product of

stream width multiplied by the average water depth, from measurements collected at 5 intervals

across the channel. Stream velocity was measured with a small piece of wood, noting the time

required to travel the 5 m channel length on 5 individual trials.

Juvenile Population Estimate

A mark-recapture survey was conducted in the Millard Creek rearing channel to determine

summer rearing usage by coho and trout and estimate their abundance. Two stop nets were used

in the upper section of the rearing channel to isolate a 250 m length of channel for the mark-

recapture survey. A total of ten Gee traps were baited with salmon roe and placed in locations

with sufficient water depth to cover the trap, and oriented to the direction of the water flow. Gee

traps consisted of ¼ inch galvanized mesh with cone shaped funnels on each end. Traps have two

parts that hinge and connect together at the center. The traps were checked the following day and

all species (salmonids and non-salmonids) were recorded. The catch from each trap was sedated

using Alka-Seltzer™ tablets in a bucket of stream water. Fork length measurements (tip of the

snout to the fork of the tail) were recorded to the nearest mm on a measuring board. Wet weight

was measured to the nearest 0.1 gram using an Ohaus electronic balance (Scout® Pro). All coho

and cutthroat trout were fin clipped (upper lobe of caudal fin squared off using clipping scissors).

After marking and sampling, fish were allowed to recover in a bucket of freshwater and the catch

was released back to the site of capture. Traps were then re-set in the same location and left to

soak for another 24 hours. On the final day of recovery, all fish caught were recorded, noting the

number of marked and unmarked coho and trout in each trap.

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Photo 3. Setting up stop nets for the marked recapture study.

Results and Discussion

Water Quality

Results from water quality sampling on the three days, as well as average measurements for

the 4 years of surveys (Moul and Kotilla 2012), are presented in Table 1. From the literature, the

preferred temperature range for juvenile rearing is 12-14 oC (Bjornn and Reiser 1991). The water

temperature measured in the rearing channel was within this range, and similar to measurements

recorded in 2008 and 2011. Similarly, dissolved oxygen averaged 98.3% saturation over the

study, which is optimal for juvenile salmonid rearing.

The pH of a water sample is a measure of its hydrogen ion concentration on a scale of 0 to

14. A pH of 7 is neutral, while values less than or greater than 7 are more acidic or basic,

respectively. The pH determines the solubility (amount that can be dissolved in the water) and

biological availability (amount that can be utilized by aquatic life) of various chemical

components such as nutrients and heavy metals (Michaud 1991). Most aquatic organisms are

sensitive to small pH changes and prefer a pH of 6.0 to 8.5. The pH in 2018 was a little higher

than this range, and higher than previous measurements in the rearing channel. This may be due

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to natural causes, from land use activities upstream (pollution), or issues with the instrument (for

example, a calibration error). Further investigation may be warranted.

Table 1. Water quality measurements in the Millard Creek rearing channel – August 22-24, 2018. Results from previous surveys for comparison (Moul and Kotilla 2012).

Date

22-Aug-18 23-Aug-18 24-Aug-18 2018

Average

Previous Surveys

2012 2011 2008

Time of day 10:20 10:00 10:30

Weather (sun, part cloud, overcast, rain)

overcast, smoke overcast Sunny

Rain in past 24 hours? none none none

Air Temperature (oC) 17 16.2 15.3 16.2 17.9 15.8 13.7

Water Temperature (oC) 13.5 13.4 12.2 13.0 15.1 13.2 12.9

Dissolved Oxygen (% Sat) 98 98 99 98.3 92 92 92

pH 8.89 8.72 8.78 8.8 7.93 7.32 n/a

Total Dissolved Solids (mg/l) 72 72 71 71.7 80 81 81

Total Dissolved Solids (TDS) is a measurement of inorganic salts, organic matter and other

dissolved materials in water, reported in mg/l. Values for fresh water naturally range from 0 to

1,000 mg/l (Cavanagh 1998). Generally, streams on the coast of B.C. have TDS concentrations

less than 75 mg/l, while interior systems have up to 750 mg/l. TDS measurements in the Millard

Creek rearing channel averaged 71.7 mg/l, and were within acceptable levels (Table 1).

Stream Discharge

The discharge in the Millard Creek rearing channel was calculated each day over the 3 day

survey. As described in the Streamkeepers Manual (Taccogna and Munro 1995), discharge is the

product of the cross-sectional area and the water velocity, multiplied by a correction factor (0.8).

The correction factor accounts for the different velocities in the water column. Water flows faster

at the surface where the object travelled and slower near the bottom of the channel. Stream

discharge ranged from 0.044 m3/s to 0.06 m3/s over the 3 days (Table 2). Discharge was also

measured on one day in the mainstem of Millard Creek, located adjacent to our sampling site in

the rearing channel, as a comparison. The 3-day average discharge in the rearing channel (0.0518

m3/s) was four times greater than the mainstem flow (0.0128 m3/s). This disproportionate flow

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may be a result of a greater amount being diverted through the intake pipe. The pipe was recently

cleaned of debris which was found to be significantly reducing flow delivery to the rearing

channel. It may also be due to a greater volume of mainstem water being diverted into the rearing

channel upstream of the valve. Average discharge in the rearing channel for the current survey,

and from the three earlier surveys in 2008, 2011 and 2012, are presented in Table 3, with 2018

having the greatest flow of all years. Unfortunately, no measurements of mainstem discharge

were conducted in the previous studies. Generally, flow diversion for side-channel development

should not exceed ~10% of the mainstem flow (M. Sheng, personal communication, November

1, 2018).

Table 2. Stream discharge calculations in the Millard Creek rearing channel, and Millard Creek mainstem, using a floating object method.

Millard Creek Rearing channel Millard Creek Mainstem

Date: 22-Aug-18 23-Aug-18 24-Aug-18 24-Aug-18

Start Finish Start Finish Start Finish Start Finish

Wetted channel width (m) 1.750 1.150 1.750 1.270 1.800 1.250 2.100 1.750

Wetted depth Measurement

location

1/6 from left bank 0.075 0.055 0.075 0.065 0.090 0.080 0.055 0.070

1/3 from left bank 0.115 0.090 0.130 0.090 0.125 0.090 0.090 0.075

centre stream 0.120 0.130 0.095 0.125 0.120 0.140 0.230 0.110

2/3 from left bank 0.100 0.130 0.100 0.135 0.110 0.130 0.120 0.075

5/6 from left bank 0.085 0.040 0.080 0.130 0.095 0.120 0.060 0.035

Average wetted depth (m) 0.099 0.089 0.096 0.109 0.108 0.112 0.111 0.073

Cross-sectional area of wetted stream (m2) 0.173 0.102 0.168 0.138 0.194 0.140 0.233 0.128

Average Cross-section area (m2) 0.138 0.153 0.167 0.180

Time in seconds (5 trials)

17.32 12.50 13.00 64.0

12.18 10.10 10.06 47.0

11.79 11.10 11.03 64.0

10.20 10.90 10.40 48.0

11.00 15.50 10.90 58.0

Average Time (sec) 12.50 12.02 11.08 56.2

Length of Glide (m) 5.0 5.0 5.0 5.0

Average Velocity (m/s) 0.400 0.416 0.451 0.089

Average Stream Discharge (m3/s) =Avg cross section area x avg velocity x 0.8 correction factor

0.0441 0.0510 0.0604 0.0128

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Table 3. Comparison of average discharge in the Millard Creek rearing channel in the 4 years of surveys. Discharge data from 2008-2012 reported in Moul and Kotilla 2012.

Survey Year Average Discharge

2008 0.0496 m3/s

2011 0.0045 m3/s

2012 0.0032 m3/s

2018 0.0518 m3/s

Juvenile Rearing

Total catches for the three day mark-recapture survey in the upper Millard Creek rearing

channel are detailed in Error! Reference source not found.. A total of 89 fish were captured on

the first day of recovery, consisting of 36 juvenile coho salmon (Oncorhynchus kisutch), 8

cutthroat trout (Oncorhynchus clarki) and 45 three-spine stickleback (Gasterosteus aculeatus).

On the final recovery day 6 marked coho and 1 marked cutthroat trout were re-captured, plus an

additional 38 unmarked coho, 4 unmarked cutthroat trout, and 37 three-spine stickleback.

However, since the stickleback (TSSB) were not marked during the first capture day, many of

those captured on the second trapping day may have been re-captures. The catches of TSSB from

both days have been summed for comparison to previous surveys in the rearing channel in Table

5. Detailed catch data is presented in Appendix 1.

Table 4. Results from Gee-trap mark-recapture survey in the Millard Creek rearing channel from 22-24 August.

August 22, 2018 - Set traps August 23, 2018 - Mark August 24, 2018 - Recapture

Trap UTM coordinates

(Zone 10) Time Total Soak Coho Cutthroat Trout Total Soak

# East North Set Coho CT TSSB Catch Time Unmk Mk Unmk Mk TSSB Catch Time

1 356601.0 5502834.0 13:05 0 1 0 1 26.0 5 0 0 1 1 7 22.5

2 356608.0 5502839.0 13:13 3 1 3 7 25.5 2 0 1 0 2 5 22.5

3 356606.5 5502851.0 13:18 7 1 1 9 25.3 0 1 1 0 2 4 22.6

4 356606.0 5502876.4 13:31 8 1 5 14 24.5 1 0 0 0 1 2 23.0

5 356612.7 5502907.3 13:38 3 3 1 7 24.0 3 0 1 0 0 4 22.5

6 356650.8 5502913.7 13:38 5 0 1 6 23.6 6 1 1 0 0 8 22.5

7 356665.3 5502919.9 13:55 7 0 15 22 22.0 6 3 0 0 14 23 23.8

8 356675.8 5502933.1 14:01 2 1 0 3 21.5 4 0 0 0 1 5 23.8

9 356687.4 5502945.9 14:12 0 0 0 0 21.0 6 0 0 0 6 12 23.8

10 356688.9 5502971.0 14:15 1 0 19 20 20.8 5 1 0 0 10 16 24.1

TOTAL 36 8 45 89 38 6 4 1 37 86

CT – cutthroat trout; TSSB – three-spine stickleback; Unmk – unmarked catch; Mk – marked or fin clipped catch.

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Concurrent to the mark-recapture study in the upper rearing channel, the MMPWS

conducted presence/absence Gee trapping in the lower section of the rearing channel to collect

information on juvenile coho salmon distribution. No effort was made to conduct mark-recapture

population estimation. Catch data for the lower trapping is detailed in Appendix 2.

Corresponding statistics for length (mm), weight (grams), and Fulton’s condition factor (K),

are summarized in Table 5 for all fish captures. Condition factor is a measure of the condition of

fish based on the relationship between weight and length, where K = (W / L3) x 100,000.

However, there are limitations in the use of this index as a measure of fish “health” therefore it is

included only to provide a general comparison to previous year’s results.

Table 5. Comparison of fish sampling statistics in the Millard Creek rearing channel, 2008-2018.

Species Biometrics 2018 2012 2011 2008

Coho Number caught (all) 74 22 46 37

Salmon Average Ln (mm) 60 66 61 70

Range Ln (mm) 43 - 96 48 - 95 49 - 75 51 - 86

Average Wt (g) 2.7 3.3 2.5 4

Range Wt (g) 0.7 - 10.1 1.1 - 9.2 1.1 - 5.6 1.6 - 7.6

Average K 1.13 1.06 1.04 1.15

Range K 0.77 - 1.66 0.92 - 1.24 0.88 - 1.63 0.82 - 1.77

Cutthroat Number caught 12 13 12 25

Trout Average Ln (mm) 105 93 104 94

Range Ln (mm) 81-134 48 – 135 51 – 158 46 – 185

Average Wt (g) 12.3 9.7 11.9 10.1

Range Wt (g) 6.4-26.2 1.0 – 23.4 1.2 – 39.2 1.0 – 31.4

Average K 1.00 0.91 0.89 1.01

Range K 0.84 - 1.2 0.56 – 1.23 0.56 – 1.02 0.28 – 1.23

Three- Number caught 82 53 1 0

spined Average Ln (mm) 60 46 65

Stickleback Range Ln (mm) 49 - 74 33 – 80

Average Wt (g) 2.6 1.2 2.8

Range Wt (g) 1.9 - 4.0 0.2 – 4.2

Average K 1.1 0.93 1.02

Range K 0.99 - 1.28 0.49 - 1.28

The total catch of coho fry was higher in 2018 than in all other previous studies, while that

of cutthroat trout was similar to 2012 and 2011. The majority of coho captured were in the 46-65

10

mm range, with an average fork length of 60 mm, the smallest on record. Length-frequency

distributions for coho and cutthroat trout are illustrated in Figure 2.

Figure 2. Length frequency histograms for coho salmon and cutthroat trout captured in the Millard Creek rearing channel, 23-24 August 2018.

Photo 4. Sampling juvenile fish populations in Millard Creek rearing channel.

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Habitat Attributes

Measurements of the physical characteristics of the reach where the Gee trapping survey

was conducted followed methods in Moul and Kotilla, 2012, and was focused mainly in pool

habitat of the ten trapping sites. The average pool depth for the 10 trap sites ranged from 0.17 m

to 0.39 m (Table 6) with an overall average pool depth for the surveyed reach of 0.26 m.

Unsurprisingly, the average pool depth over the surveyed reach in 2012 was only 0.16 m due to

the lower flows observed in that year.

In addition to the instream salmonid habitat, the riparian corridor of the Millard Creek

rearing channel was observed to provide habitat for a variety of other wildlife species, including

red-legged frogs, Pacific tree frogs, Pacific sideband snails, and many bird species.

Table 6. Summary of habitat measurements at Gee trap locations in the rearing channel, August 23, 2018.

Trap Water depth at trap location (m) Wetted Channel Bankful Pool Tail

# D1 D2 D3 D4 D5 Average

Depth (m) Width (m) Width (m) Depth (m) Crest Depth

(m)

1 0.13 0.16 0.26 0.27 0.14 0.19 3.35 4.40 0.30 0.10

2 0.25 0.29 0.30 0.32 0.09 0.25 2.05 2.40 0.30 0.14

3 0.10 0.18 0.29 0.23 0.21 0.20 1.98 2.20 0.29 0.13

4 0.17 0.20 0.28 0.27 0.26 0.24 1.97 1.60 0.44 0.09

5 0.19 0.26 0.19 0.26 0.32 0.24 3.00 3.00 0.25 0.05

6 0.22 0.25 0.20 0.12 0.07 0.17 2.32 1.90 0.23 0.07

7 0.16 0.27 0.35 0.37 0.39 0.31 2.55 2.65 0.09 0.05

8 0.15 0.34 0.49 0.40 0.22 0.32 4.50 4.50 0.22 0.06

9 0.26 0.35 0.43 0.45 0.45 0.39 2.10 2.30 0.14 0.07

10 0.10 0.50 0.43 0.32 0.14 0.30 3.50 3.20 0.56 0.15

Reach Average 0.26 2.73 2.82 0.28 0.09

The catch per unit effort (CPUE) is an indirect measure of the abundance of a target species

and expressed as the number of fish captured per hour of fishing time. CPUE for coho and

cutthroat trout is summarized in Table 6, and was slightly higher on Day 2 than Day 1 for coho.

Overall, the 2018 CPUE for coho was over double than previous years, while CPUE for cutthroat

trout was more comparable to the previous surveys.

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Table 7. Catch per unit effort (CPUE) for coho and cutthroat in the Millard Creek rearing channel, 2011-2018.

2018 2012 2011

Coho Day 1 0.152 0.068 0.067

Day 2 0.189 0.026 0.110

Cutthroat trout Day 1 0.033 0.038 0.029

Day 2 0.022 0.018 0.008

Juvenile Population Estimate

The adjusted Chapman-Petersen method described in Ricker (1975) was used to estimate the

population (N) of the channel using the formula:

N = (M+1)*(C+1) (1)

(R+1)

Where:

N is the estimate of the total population

M is the number of fish marked

C is the catch or sample taken for census (marks + unmarked)

R is the number of recaptured marks in the sample

Ricker (1975) states that the probability of a systematic statistical bias in the population

estimate can be ignored if recaptures number 3-4 or more. Therefore the “-1” variation used in

the following equation from previous studies, is not necessary.

N = (M+1)*(C+1) -1 (2)

(R+1)

Using equation (1), the population in the upper Millard Creek rearing channel was estimated

at 238 individuals for coho and 27 for cutthroat trout (Table 8). Based on the area that was

surveyed in the rearing channel (250 m long by 2.73 m wide), this estimate works out to ~0.35

coho fry/m2 and 0.04 trout/m2. Coho abundance was highest in the current year of study than all

previous surveys, while cutthroat trout was on the low end, and comparable to the 2011

estimates. Higher late-summer rearing flows and greater wetted habitat and pool depth likely

account, to some degree, for the higher densities of coho. Coho escapement data for 2017 would

be helpful in interpreting the variation in coho abundance over the 4 years of surveys. Population

estimation was not conducted on three-spine stickleback, however more TSSB were captured in

2018 (82) than previous surveys, if the catch from both days are summed. As noted above the

total catch is more likely between 45 and 82 individuals.

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Table 8. Comparison of population estimates in the Millard Creek rearing channel.

Coho Cutthroat

Number of individuals marked in first sample (M) 36 8

Total caught in second sample (C) 44 5

Total marked individuals recaptured in second sample (R) 6 1

Fish population estimate

2018 238 27

2012 59 49

2011 91 26

2008 80 65

Community outreach

The YERII Youth, Isa Faria and Heidi Morfitt, learned how to: execute the marked

recapture fish population method; identify and sample juvenile salmon and trout; assess stream

flows and habitat; and deliver a public tour. They were eager to learn and excelled in all of the

tasks presented to them. The public tour on the final day was attended by fourteen people. Isa

and Heidi demonstrated the fish sampling methods, shared the ecological values of the rearing

channel habitat and integrated their personalities into the tour content. From a YER perspective

the project was a success.

Photo 5. Isa Faria and Heidi Morfitt co-facilitate a public tour of the YERII study.

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Recommendations

A routine monitoring and maintenance schedule for the Millard Creek rearing channel

rearing channel intake should be implemented to ensure adequate rearing flows are available,

particularly during critical times of the year. Routine monitoring should also include an

assessment of diversion flows (and other inflows) relative to the Millard Creek mainstem to

ensure optimum flow rates in both channels.

Additional water quality sampling should be conducted to investigate the elevated pH

measurements that were observed in 2018.

A comparison of the coho population estimates to adult spawner counts in Millard Creek

over the years juvenile surveys were completed may provide more insight into the variation in

coho production in the rearing channel.

Summary

The 2018 fish habitat and juvenile population study in the Millard Creek rearing channel has

confirmed that the channel continues to support a healthy salmonid population, and contributes

valuable rearing habitat in the Millard Creek watershed. The 2018 summer rearing coho juvenile

population estimate was the highest recorded in the 4 years of mark-recapture studies in the

channel. Further investigation into the performance of the intake valve and flows into the rearing

channel should be conducted. In addition, the area also provides habitat for a variety of wildlife

species which were observed during the study, including red-legged frogs, Pacific tree frogs,

Pacific sideband snails, and many bird species.

This was a community partnership with Millard Piercy Watershed Stewards and Youth and

Ecological Restoration. It is the fourth YERII project conducted in collaboration with the two

groups on the Millard Creek rearing channel. The two youth advanced their ecological research

and teamwork skills. The public tour they gave on the final day was well received and improved

the knowledge of the participants.

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References

Cavanagh, N. 1998. Guidelines for interpreting water quality data. Field test Edition Version 1.0.

B.C. Environment, Water quality Branch, Resources Inventory Committee.

Bjornn, T. C., & Reiser, D. W. 1991. Habitat Requirements of Salmonids in Streams. In W.

Meehan (Ed.), Influence of Forest and Rangeland Management of Salmonid Fishes and

Their Habitats (pp. 83–138). Fisheries Society Special Publication 19.

Michaud, J.P. 1991. A citizens’ guide to understanding and monitoring lakes and streams. Puget

Sound Water Quality Authority.

Moul, I. and W. Kotilla. 2012. Millard Creek Rearing Channel Fish Habitat and Productivity

Report 2012. Prepared for Millard Piercy Watershed Stewards, Courtenay B.C.

Ricker, W.E. 1975. Computation and interpretation of biological statistics of fish populations.

Bull. Fish. Res. Board Can. 191, 382 p.

Taccogna, G. and K. Munro (eds). 1995. The Streamkeepers Handbook: a Practical Guide to

Stream and Wetland Care. Salmonid Enhancement Program, Dept. Fisheries and Oceans,

Vancouver, B.C.

Youth and Ecological Restoration Program. 2018. http://youthecology.ca/. Accessed October 22,

2018.

Personal Communication

Mel Sheng Fisheries and Oceans Canada, Habitat Restoration Biologist (retired);

email November 1, 2018.

16

Appendix 1. Fish captures in the upper Millard Creek rearing channel August 22-24, 2018.

Coho Cutthroat Trout Threespine Stickleback

Date Trap # Ln (mm) Weight K Ln (mm) Weight K Ln

(mm) Weight K

23-Aug 1 90 7.7

23-Aug 2 65 3.3 1.20 134 26.2 1.09

23-Aug 2 57 2 1.08

23-Aug 2 55 1.7 1.02

23-Aug 3 56 2.1 1.20 105 9.7 0.84

23-Aug 3 59 2.2 1.07

23-Aug 3 55 1.9 1.14

23-Aug 3 59 2.5 1.22

23-Aug 3 65 3 1.09

23-Aug 3 62 2.5 1.05

23-Aug 3 49 1.2 1.02

23-Aug 4 82 6.3 1.14 95 8.5 0.99

23-Aug 4 54 1.7 1.08

23-Aug 4 48 1.1 0.99

23-Aug 4 64 2.6 0.99

23-Aug 4 52 1.5 1.07

23-Aug 4 50 1.3 1.04

23-Aug 4 61 2.6 1.15

23-Aug 4 65 4 1.46

23-Aug 5 65 3.2 1.17 134 23.1 0.96 65 2.9 1.06

23-Aug 5 50 1.2 0.96 101 9.5 0.92

23-Aug 5 81 6.3 1.19 99 8.9 0.92

23-Aug 6 60 2.4 1.11 60 2.5 1.16

23-Aug 6 63 2.8 1.12

23-Aug 6 49 1.2 1.02

23-Aug 6 68 3.5 1.11

23-Aug 6 55 2.1 1.26

23-Aug 7 59 2.4 1.17 49

23-Aug 7 72 4.1 1.10 67

23-Aug 7 68 3.6 1.14 55

23-Aug 7 66 3 1.04 55

23-Aug 7 54 1.6 1.02 52

23-Aug 7 63 3.1 1.24

23-Aug 7 45 0.7 0.77

23-Aug 8 84 7.5 1.27 107 12 0.98

23-Aug 8 88 8.3 1.22

23-Aug 10 67 3.6 1.20 65 2.8 1.02

23-Aug 10 56 2 1.14

23-Aug 10 57 1.9 1.03

23-Aug 10 61 2.5 1.10

23-Aug 10 64 2.7 1.03

23-Aug 10 56 1.9 1.08

23-Aug 10 62 2.8 1.17

23-Aug 10 61 2.9 1.28

17

Appendix 1 cont’d

Coho Cutthroat Trout Threespine Stickleback

Date Trap # Ln (mm) Weight K Ln (mm) Weight K Ln

(mm) Weight K

23-Aug 10 74 4 0.99

24-Aug 1 60 2.5 1.16

24-Aug 1 50 1.3 1.04

24-Aug 1 54 2 1.27

24-Aug 1 49 1.2 1.02

24-Aug 1 49 1.5 1.27

24-Aug 2 49 1.2 1.02 117 16.6 1.04

24-Aug 2 51 2.2 1.66

24-Aug 3 81 6.4 1.20

24-Aug 4 60 2.4 1.11

24-Aug 5 47 1.2 1.16 88 7 1.03

24-Aug 5 50 1.2 0.96

24-Aug 5 60 2.7 1.25

24-Aug 6 53 1.7 1.14 106 11.9 1.00

24-Aug 6 51 1.5 1.13

24-Aug 6 58 2 1.03

24-Aug 6 53 1.5 1.01

24-Aug 6 56 1.8 1.02

24-Aug 6 43 1 1.26

24-Aug 7 57 1.9 1.03

24-Aug 7 55 2.1 1.26

24-Aug 7 50 1.5 1.20

24-Aug 7 62 3.2 1.34

24-Aug 7 46 1.1 1.13

24-Aug 7 55 1.7 1.02

24-Aug 8 65 3.3 1.20

24-Aug 8 65 2.8 1.02

24-Aug 8 74 5.1 1.26

24-Aug 8 62 2.7 1.13

24-Aug 9 63 2.4 0.96

24-Aug 9 96 10.1 1.14

24-Aug 9 63 2.8 1.12

24-Aug 9 66 3.5 1.22

24-Aug 9 59 2.1 1.02

24-Aug 9 87 7.6 1.15

24-Aug 10 64 2.8 1.07

24-Aug 10 67 2.8 0.93

24-Aug 10 70 4.1 1.20

24-Aug 10 60 2.7 1.25

24-Aug 10 55 1.9 1.14

18

Appendix 2. Coho salmon captures in the lower Millard Creek rearing channel August 22-23, 2018 (conducted concurrently by MPWS volunteers).

Trap # Fish # Length (mm) Weight (g) K

1 1 50 1.8 1.44

2 2 58 2.1 1.08

2 3 55 2.1 1.26

2 4 86 7.1 1.12

2 5 48 1.4 1.27

2 6 72 4.5 1.21

3 7 50 1.3 1.04

3 8 59 2.3 1.12

3 9 49 1.4 1.19

3 10 47 1.2 1.16

4 11 69 3.5 1.07

4 12 52 2 1.42

4 13 52 1.8 1.28

4 14 70 4.1 1.20

4 15 58 2.4 1.23

5 16 70 3.2 0.93

5 17 62 2.8 1.17

5 18 50 1.4 1.12

6 19 70 4.8 1.40

7 20 49 1.3 1.10

7 21 52 1.8 1.28

7 22 66 3 1.04

7 23 47 1.1 1.06

7 24 48 1.4 1.27

7 25 60 3 1.39

7 26 48 1.3 1.18

8 27 44 0.8 0.94

8 28 55 1.4 0.84

8 29 64 2.3 0.88

8 30 65 3 1.09

10 31 64 2.1 0.80

10 32 64 2.7 1.03

10 33 66 3.4 1.18

10 34 50 1.4 1.12

10 35 62 2.7 1.13

10 36 70 3.8 1.11

10 37 53 1.9 1.28

Mean 58 2.42 1.15

Max 86 7.1 1.44

Min 44 0.8 0.80

N 37