17
Amenities Informational kiosks Marina Boat ramps Picnic areas Modern restrooms Showers RV hook-ups Designated tent camping Hiking trails Fishing (open water and ice) Hunting Wildlife viewing Regulations Min. size for walleye and saugeye is 15” (only 1 can exceed 21”). Min. size for wiper is 15(only 1 can exceed 25”). Min. size for largemouth bass is 15”. Min. size for smallmouth bass is 12”. Statewide bag and possession limits also apply. Entry requires a Colorado State Parks Pass, which is available on site. General Information: North Sterling Reservoir is a 2,880 acre water (at full capacity). The reservoir pro- vides excellent fishing for wiper, walleye, saugeye, and crappie, and quality fishing for channel catfish. Please visit the state park website at: http://cpw.state.co.us/placestogo/Parks/northsterling for updated water and fishing conditions. Location: Logan County. From I-76 take Exit 125 and head 12 miles north on CR 39 to CR 46. Take CR 46 2 miles west to the reservoir. Recreational Management: Colorado Parks and Wildlife Fishery Management: Warmwater angling Purchase a Fishing License: http://cpw.state.co.us/buyapply/Pages/Fishing.aspx Previous Stocking 2015 Walleye and Saugeye Wiper Largemouth bass Channel catfish Black crappie Bluegill Cuttbow 2014 Walleye and Saugeye Wiper Largemouth bass Channel catfish Black crappie Bluegill Rainbow trout 2013 Walleye and Saugeye Wiper Largemouth bass Channel and Blue catfish Black crappie Bluegill Rainbow trout and Cuttbow Sportfishing Notes Walleye and Saugeye Fish the dam during early spring when the water temperature is 40-50°F. Boat anglers do well jig- ging, trolling or casting shad raps, and trolling wally divers during late spring and early summer. Fish rocky areas, drop-offs, and flats in each arm of the reservoir at other times. Wiper Fish the inlet when the reservoir is filling and fish open water at other times. Fish are often found chasing shad, so use shad imitations and follow the seagulls. Green mussels as bait work well. Channel catfish Fish coves and reservoir arms, especially during August and September. Cut shad, cut carp, and shrimp as bait work well. North Sterling Reservoir LAST UPDATED: JANUARY 2016 FISH SURVEY AND MANAGEMENT DATA Mandi Brandt - Aquatic Biologist (Brush) [email protected]

North Sterling Reservoir Fish Survey and Management Data Survey Summaries... · Due to water breeching the inlet canal in several places, the reservoir was not filled until 1912

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Amenities Informational kiosks

Marina

Boat ramps

Picnic areas

Modern restrooms

Showers

RV hook-ups

Designated tent camping

Hiking trails

Fishing (open water and ice)

Hunting

Wildlife viewing

Regulations

Min. size for walleye and

saugeye is 15” (only 1 can

exceed 21”).

Min. size for wiper is

15” (only 1 can exceed 25”).

Min. size for largemouth

bass is 15”.

Min. size for smallmouth

bass is 12”.

Statewide bag and

possession limits also apply.

Entry requires a Colorado

State Parks Pass, which is

available on site.

General Information: North Sterling Reservoir is a 2,880 acre water (at full capacity). The reservoir pro-

vides excellent fishing for wiper, walleye, saugeye, and crappie, and quality fishing for channel catfish.

Please visit the state park website at: http://cpw.state.co.us/placestogo/Parks/northsterling for updated water

and fishing conditions.

Location: Logan County. From I-76 take Exit 125 and head 12 miles north on CR 39 to CR 46. Take CR 46

2 miles west to the reservoir.

Recreational Management: Colorado Parks and Wildlife

Fishery Management: Warmwater angling

Purchase a Fishing License: http://cpw.state.co.us/buyapply/Pages/Fishing.aspx

Previous Stocking

2015

Walleye and Saugeye

Wiper

Largemouth bass

Channel catfish

Black crappie

Bluegill

Cuttbow

2014

Walleye and Saugeye

Wiper

Largemouth bass

Channel catfish

Black crappie

Bluegill

Rainbow trout

2013

Walleye and Saugeye

Wiper

Largemouth bass

Channel and Blue catfish

Black crappie

Bluegill

Rainbow trout and Cuttbow

Sportfishing Notes Walleye and Saugeye

Fish the dam during early

spring when the water

temperature is 40-50°F.

Boat anglers do well jig-

ging, trolling or casting

shad raps, and trolling wally

divers during late spring

and early summer.

Fish rocky areas, drop-offs,

and flats in each arm of the

reservoir at other times.

Wiper

Fish the inlet when the

reservoir is filling and fish

open water at other times.

Fish are often found chasing

shad, so use shad imitations

and follow the seagulls.

Green mussels as bait work

well.

Channel catfish

Fish coves and reservoir

arms, especially during

August and September.

Cut shad, cut carp, and

shrimp as bait work well.

North Sterling Reservoir LAST UPDATED: JANUARY 2016

FISH SURVEY AND MANAGEMENT DATA Mandi Brandt - Aquatic Biologist (Brush)

[email protected]

North Sterling Reservoir LAST UPDATED: JANUARY 2016

FISH SURVEY AND MANAGEMENT DATA Mandi Brandt - Aquatic Biologist (Brush)

[email protected]

North Sterling Reservoir, once known as Point of Rocks Reservoir, was built by the Empire Construction

Company between 1909 and 1911, making the reservoir approximately 105 years old. Water used to fill

North Sterling Reservoir is taken from the South Platte River near the town of Snyder, and flows down a

62-mile long earthen canal before reaching the reservoir. Due to water breeching the inlet canal in several

places, the reservoir was not filled until 1912. The reservoir was stocked with black bass and yellow perch

before it officially opened in 1913. In 1915, black crappie were also stocked.

Since the primary function of North Sterling Reservoir is to store irrigation water, water levels routinely

drop during the irrigation season. During a typical year, water levels can fluctuate by approximately 40 ft,

reducing the reservoir’s volume to about one-seventh of its capacity (Figure 1). Unfortunately, the reservoir

is drawn down while panfish are spawning, limiting

recruitment of critical prey species such as bluegill and

gizzard shad. These young fish seek refuge in

littoral habitat, but this habitat is lost as the water

level begins to drop, increasing their vulnerability

to predation. The risk of being consumed is heightened

as the water level continues to drop and fish are concentrated into a successively smaller

pool. Young fish of other species such as walleye, saugeye, wiper, and crappie are also

negatively impacted by reservoir draw down.

About the Reservoir...

0

10,000

20,000

30,000

40,000

50,000

60,000

70,000

80,000

Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb

Vo

lum

e (a

cre-f

eet)

Month

Figure 1. Water level fluctuation

at North Reservoir during a

typical year. Prior to the

irrigation season, which

usually starts in May, the

reservoir is usually at

full capacity (red

dotted line). During

the irrigation season

(May-October) the

reservoir is routinely

drawn down, often to

approximately one-seventh

of its capacity. Refilling usually

begins near the end of October and

continues through the winter months

(December-February) when possible. The

reservoir is then topped off in the spring

(March-April).

North Sterling Reservoir LAST UPDATED: JANUARY 2016

FISH SURVEY AND MANAGEMENT DATA Mandi Brandt - Aquatic Biologist (Brush)

[email protected]

In 2012, the reservoir’s water level was drastically reduced

due to severe drought conditions. The low water level, in

combination with decaying organic matter from an earlier

blue-green algae bloom, created a perfect storm that re-

sulted in a mid-September fish kill. High winds turned the

reservoir over, forcing decaying organic matter from the

bottom of the lake up to the top of the water column, deple-

About the Fish Kill...

ting oxygen that the fish

were depending on to sur-

vive. Colorado Parks and

Wildlife crews found at

least one fish of every spe-

cies that inhabits the reser-

voir dead along the shore-

line. Though the reservoir

did not suffer a complete

fish kill, catch-per-unit-

effort decreased by 80%

from the 2011 to 2012 an-

nual survey (Table 1).

While some primary

predators such as walleye

were not drastically effect-

ed by the partial summerkill,

other primary predators

such as wiper were (Table 1).

While it was terrible to lose

so many predatory sportfish,

the loss allowed panfish spe-

cies to flourish (Table 1),

which has helped create ex-

cellent black crappie, white

crappie, yellow perch and

bluegill fisheries.

* 80% decrease in the catch-per-unit-effort after the 2012 partial summerkill.

** Bluegill, white crappie, largemouth bass, channel catfish, northern pike, and freshwater drum were not caught dur-

ing the 2012 annual survey. Though some of these species (e.g., northern pike and largemouth bass) are usually caught

in low numbers, other species (e.g., bluegill and channel catfish) are routinely caught during annual surveys, indicating

the 2012 fish kill negatively affected these species among others.

***Prey and panfish species such as gizzard shad, black crappie, white crappie, and bluegill rebounded and prospered

following the 2012 partial summerkill, which killed a large portion of the wiper (primary predator) population.

****Increase in catch-per-unit-effort after the prey and panfish species such as gizzard shad, black crappie, white

crappie, and bluegill rebounded and prospered following the 2012 partial summerkill, which killed a large portion of

the wiper (primary predator) population.

North Sterling Reservoir LAST UPDATED: JANUARY 2016

FISH SURVEY AND MANAGEMENT DATA Mandi Brandt - Aquatic Biologist (Brush)

[email protected]

About the Fish Kill... Table 1. North Sterling Reservoir 2011-2014 annual survey summaries. Fish were caught using four gillnets

and three trap nets in all surveys. In 2011, 2012, 2013, and 2014 gillnets and trap nets were fished for a total

of 64 and 54 hours, 65 and 52 hours, 87 and 78 hours, and 107 and 74 hours, respectively.

2011 2012 2013 2014 2011 2012 2013 2014 2011 2012 2013 2014

Gizzard shad 280 32 395 91 4.4 0.5 5.2*** 0.5*** 56.34 27.59 31.70 20.92

Black crappie 16 23 127 31 0.3 0.3 1.6*** 0.2*** 3.22 19.83 10.19 7.13

White crappie 28 0 224 40 0.5 ** 2.9*** 0.2*** 5.63 17.98 9.20

Yellow perch 4 1 5 3 0.0 0.0 0.1 0.0 0.80 0.86 0.40 0.69

Walleye 33 22 33 54 0.5 0.3 0.5 0.3 6.64 18.97 2.65 12.41

Saugeye 0 2 19 21 0.0 0.4 0.1 1.72 1.52 4.83

Wiper 23 1 14 0 0.4 0.0 0.2 4.63 0.86 1.12

Bluegill 7 0 153 8 0.1 ** 2.0*** 0.1*** 1.41 12.28 1.84

Orangespotted sunfish 0 0 7 0 0.1 0.56

Green sunfish 0 0 18 0 0.2 1.44

Channel catfish 13 0 5 10 0.2 ** 0.1 0.1 2.62 0.40 2.30

Largemouth bass 4 0 4 3 0.1 ** 0.0 0.0 0.80 0.32 0.69

Northern pike 1 0 0 0 0.0 ** 0.20

Freshwater drum 4 0 5 16 0.1 ** 0.1 0.1 0.80 0.40 3.68

Quillback 0 0 91 0 1.1 7.30

River carpsucker 68 30 21 53 1.1 0.5 0.3 0.3 13.68 25.86 1.69 12.18

Common carp 16 5 125 104 0.2 0.0 1.8 0.6 3.22 4.31 10.03 23.91

TOTAL: 497 116 1246 434 7.9 1.6* 16.6**** 2.5**** 100 100 100 100

Species

Number Caught Catch Per Unit Effort Relative Abundance

(number of fish) (number per hour) (percent)

North Sterling Reservoir LAST UPDATED: JANUARY 2016

FISH SURVEY AND MANAGEMENT DATA Mandi Brandt - Aquatic Biologist (Brush)

[email protected]

As in many of Colorado’s reser-

voirs, gizzard shad are relied upon

as the primary prey species for

sportfish in North Sterling Reser-

voir because the species is a broad-

cast spawner and is highly prolific

(250,000 eggs per female). Unfortu-

nately, there was extremely poor

gizzard shad recruitment in the

reservoir in 2006, 2007, and 2008

(Figure 2), leaving sportfish in

poor condition.

Reservoir draw down, winterkill,

and nutrient inadequacies are re-

sponsible for the lack of recruit-

ment. Large drawn downs oc-

curred in 2005 and 2006. In 2006,

the reservoir was substantially drawn down during the irrigation season due to severe drought, resulting in

a very low pool level during the winter. Gizzard shad could not withstand the poor water quality in the pool

and succumbed to winterkill, leaving extremely low numbers of adults in 2007 and 2008 to produce young

fish. Even if young gizzard shad were produced, the zooplankton prey base would not have been large

enough at the time to support the gizzard shad. Relatively small numbers of zooplankton were available to

eat, likely due to low levels of

nutrients that would normally

support phytoplankton, which

would in turn support zoo-

plankton.

In an effort to re-establish the

reservoir’s gizzard shad popu-

lation, crews from the former

Division of Wildlife initiated a

shoreline grass seeding project

and an adult gizzard shad

stocking program. In 2009 and

2010 crews seeded shorelines

with Japanese millet and annual

rye to return nutrients that

were locked up in the reser-

voir’s soil to the water column.

About the Grass Seeding Project...

North Sterling Reservoir LAST UPDATED: JANUARY 2016

FISH SURVEY AND MANAGEMENT DATA Mandi Brandt - Aquatic Biologist (Brush)

[email protected]

About the Fish... The idea behind shoreline seeding is that as the grass grows, it

takes up nutrients from the soil. Then, when the grass is inun-

dated by water it is killed and these nutrients are released into the

water column where they are available to phytoplankton. This

creates a positive bottom-up effect in the food-web in which more

nutrients are available to support more phytoplankton, which in

turn can support more zooplankton, which in turn can support

more gizzard shad, which in turn can support more sportfish.

In addition to seeding shorelines, crews began an adult gizzard shad stocking program. Approximately 700

adult gizzard shad have been stocked into the reservoir since the spring of 2009. As hoped, the gizzard shad

spawned and substantial recruitment returned in 2009 through 2011, supplying sportfish with a much

needed prey base (Figure 2). Unfortunately, the gizzard shad population took a severe hit during the 2012

fish kill (Table 1; Figure 2). While the fish kill initially resulted in the loss of gizzard shad, the gizzard shad

population expanded due to less predatory pressure from species such as wiper (Table 1; Figure 2). In 2014

and 2015 the walleye and saugeye populations flourished on the robust gizzard shad prey base, which has

caused the pendulum to swing yet again, resulting in a low catch of gizzard shad during the 2015 annual

survey (Table 2; Figures 2-3).

Gizzard shad

Figure 2. Gizzard shad catch-per-unit-

effort (CPUE) during the 2005 to 2015 an-

nual surveys at North Sterling Reservoir.

For comparative purposes, the number of

fish collected was standardized per gillnet.

Severe draw downs in 2005 and 2006, fol-

lowed by a gizzard shad winterkill in the

winter of 2006, led to poor recruitment in

2007 and 2008. Recruitment rebounded in

2009 through 2011 as a result of shoreline

grass seeding and adult gizzard shad

stocking. Gizzard shad CPUE was drasti-

cally reduced again in 2012 since a large

portion of the population died during the

fish kill. The loss of predatory fish during

the fish kill allowed the gizzard shad

population to rebound in 2013 and 2014,

increasing CPUE. However, the gizzard

shad population supported enough preda-

tors in 2014 and 2015 to consume most of

the gizzard shad by the 2015 annual sur-

vey.

North Sterling Reservoir LAST UPDATED: JANUARY 2016

FISH SURVEY AND MANAGEMENT DATA Mandi Brandt - Aquatic Biologist (Brush)

[email protected]

About the Fish... Table 2. Summary data for fish caught during the 2015 annual survey at North Sterling Reservoir.

Data are based on 78 hours of gillnetting and 99 hours of trap netting.

Walleye 187 17.35 14.85 7.83 - 27.32 1.42 0.18 - 8.87

Saugeye 24 2.23 9.82 8.70 - 10.71 0.33 0.21 - 0.46

Northern pike 1 0.09 39.69 39.69 - 39.69 17.56 17.56 - 17.56

Largemouth bass 10 0.93 9.92 5.71 - 13.94 0.72 0.10 - 1.66

Channel catfish 11 1.02 17.93 10.87 - 24.33 2.37 0.41 - 5.63

Black crappie 36 3.34 8.31 3.07 - 12.64 0.47 0.01 - 1.53

White crappie 152 14.10 7.48 2.13 - 12.80 0.41 0.01 - 1.23

Bluegill 291 26.99 3.91 1.34 - 7.48 0.05 0.01 - 0.34

Green sunfish 3 0.28 4.33 3.74 - 5.08 0.05 0.03 - 0.08

Hybrid sunfish 1 0.09 6.89 6.89 - 6.89 0.27 0.27 - 0.27

Orange-spotted sunfish 87 8.07 2.95 2.36 - 3.90 0.01 0.01 - 0.04

Freshwater drum 7 0.65 14.06 12.17 - 16.73 1.44 0.76 - 2.53

Black bullhead 1 0.09 7.28 7.28 - 7.28 0.21 0.21 - 0.21

Quillback 1 0.09 18.03 18.03 - 18.03 2.92 2.92 - 2.92

River carpsucker 73 6.77 16.81 11.06 - 23.82 2.56 0.73 - 7.52

Common carp 30 2.78 19.79 16.61 - 26.30 3.39 1.56 - 7.83

Gizzard shad 53 4.92 11.72 2.60 - 14.84 0.73 0.01 - 1.33

Species

Number

caught

Relative

abundance

(%)

Average

length

(in)

Length

range

(in)

Average

weight

(lbs)

Weight

range

(lbs)

39.7 in; 17.6 lb

North Sterling Reservoir LAST UPDATED: JANUARY 2016

FISH SURVEY AND MANAGEMENT DATA Mandi Brandt - Aquatic Biologist (Brush)

[email protected]

Walleye and saugeye Walleye were first stocked in 1949, and were one of the species that made North Sterling Reservoir one of

Colorado’s premier warmwater fisheries during the 1970s. During the early 1980s rough fish (common

carp and river carpsucker) all but overtook the reservoir. To improve the fishery, the reservoir was chemi-

cally reclaimed by the former Colorado Division of Wildlife in 1985. Many efforts were made during the

late 1980s and 1990s to rebuild the walleye fishery; however, it never bounced back to its former self,

partly due to the introduction of wiper. In 2004, crews tried once again to build a premier walleye and

saugeye fishery by drastically increasing fry and fingerling stocking rates. Since that time, nearly 46.6 mil-

lion walleye and saugeye have been stocked into North Sterling Reservoir. Though annual surveys from

2005 to 2009 yielded extremely low numbers of walleye and saugeye, the 2010 and 2011 surveys indicated

walleye and saugeye were on their way to making a comeback before the 2012 fish kill (Figure 3). Fortu-

nately, the fish kill had a relatively small impact on these two species, as opposed to wiper (Figures 3 and

5). By 2013, the size of the walleye population surpassed the populations of the 1970s that made North Ster-

ling a premier warmwater reservoir (Figure 3). The average number (52) of walleye and saugeye caught

per gillnet in 2015 is the highest recorded catch in history for North Sterling Reservoir (Table 2; Figure 3).

This catch is currently the third largest in the state, following 123 and 89 per net at Jumbo Reservoir and

Jackson Reservoir, respectively. Walleye and saugeye caught during the 2015 annual survey were in excel-

lent condition (Figure 4). Walleye were 14.85” and 1.42lbs on average, with the largest (walleye) measuring

27.32” and weighing 8.87 lbs (Table 2; Figures 3-4). Walleye and saugeye fishing was excellent during 2015,

and based on the number

and sizes of walleye and

saugeye caught during

the 2015 annual sample,

should be even better

during the 2016 fishing

season.

About the Fish...

Figure 3. Walleye and

saugeye catch-per-unit-

effort (CPUE) during

the 2005 to 2006 and

2008 to 2015 annual sur-

veys at North Sterling

Reservoir. For com-

parative purposes, the

number of fish collected

was standardized per

gillnet.

0

10

20

30

40

50

60

Wa

lley

e/S

au

gey

e C

PU

E

(#/n

et)

Year

≥ 25.0"

20.0 - 24.9"

15.0 - 19.9"

10.1 - 14.9"

≤ 10.0"

North Sterling Reservoir LAST UPDATED: JANUARY 2016

FISH SURVEY AND MANAGEMENT DATA Mandi Brandt - Aquatic Biologist (Brush)

[email protected]

About the Fish...

Figure 4. Length-weight regression for walleye and saugeye caught during the 2014 and 2015 annual sur-

veys at North Sterling Reservoir. Stock (S), quality (Q), preferred (P), and memorable (M) size categories

are indicated in green. Colorado’s Master Angler Award length for walleye and saugeye is indicated in red.

Data are based on 107 and 78 hours of gillnetting in 2014 and 2015, respectively.

y = 0.0003x3.1409

R² = 0.9633

y = 0.0002x3.2364

R² = 0.9933

0.0

1.0

2.0

3.0

4.0

5.0

6.0

7.0

8.0

9.0

10.0

6.0 8.0 10.0 12.0 14.0 16.0 18.0 20.0 22.0 24.0 26.0 28.0 30.0

Wei

gh

t (l

b)

Total Length (in)2014 2015

S

Q

P

M

Master Angler Award

Walleye and saugeye

North Sterling Reservoir LAST UPDATED: JANUARY 2016

FISH SURVEY AND MANAGEMENT DATA Mandi Brandt - Aquatic Biologist (Brush)

[email protected]

Wiper Though catch rates of wiper were generally higher

than those of walleye and saugeye during the 2005 to

2009 annual surveys, wiper abundance was relatively

low through these years (Figures 4-5). Abundance

really dropped in 2009 through 2011 because fewer

wiper were stocked to decrease predatory pressure

while efforts were made to re-establish the gizzard

shad prey base (Figure 5). Only one wiper (20.9” and

4.6 lbs) was caught during the 2012 annual survey,

indicating the wiper population took a substantial hit during the 2012 fish kill (Table 1; Figure 5). As ex-

pected, the gizzard shad population had a positive response to the loss of predators resulting from the fish

kill (Figure 2). It was felt the gizzard shad prey base could support more predatory fish; thus, substantial

numbers of wiper were stocked into the reservoir in 2013-2015. Annual surveys indicated that some of these

wiper survived in 2013, but not in 2014 or 2015 (Tables 1-2; Figure 5). The survival of this young age-class

of fish is vitally important because these fish will help form the future wiper population. Without their sur-

vival, the population, which was composed of older age-classes in recent years, would eventually disappear

(Figure 5). Though the majority of anglers target wiper at North Sterling Reservoir (Figure 9), the species

has had little success in recent years. Although efforts will be made to re-establish a wiper population, fu-

ture predatory management will primarily

focus on walleye and saugeye, which have

proved to provide an excellent fishery in

recent years.

About the Fish...

Figure 5. Wiper catch-per-unit-effort (CPUE) during the

2005 to 2006 and 2008 to 2015 annual surveys at North Ster-

ling Reservoir. For comparative purposes, the number of fish

collected was standardized per gillnet.

0

2

4

6

8

10

12

14

16

18

Wip

er C

PU

E

(#/n

et)

Year

≥ 25.0"

20.0 - 24.9"

15.0 - 19.9"

10.1 - 14.9"

≤ 10.0"

North Sterling Reservoir LAST UPDATED: JANUARY 2016

FISH SURVEY AND MANAGEMENT DATA Mandi Brandt - Aquatic Biologist (Brush)

[email protected]

Figure 6. Length-weight regression for black and white crappie caught during the 2015 annual survey at

North Sterling Reservoir. Stock (S), quality (Q), preferred (P), and memorable (M) size categories are indi-

cated in green. Colorado’s Master Angler Award length for crappie is indicated in red. Data are based on

78 of gillnetting and 99 hours of trap netting, respectively.

Crappie (black and white) Though it was terrible to lose so many preda-

tory sportfish during the 2012 fish kill, the loss allowed

panfish species such black crappie and white crappie

to flourish (Tables 1-2). In fact, crappie catch-per-unit-

effort was 15 times higher in the 2013 annual survey

than it was in the 2012 annual survey (Table 1). Based

on the crappie caught during the 2015 annual survey,

anglers can expect excellent fishing during the 2016

season (Table 2; Figure 6). In addition to good num-

bers of quality-sized (8-10”) crappie, anglers will have

the opportunity to catch several preferred- (10-12”)

and memorable-sized (12-15”) fish (Figure 6). Trophy-

sized (>15”) crappie are undoubtedly lurking in the

reservoir. Catch rates for stock-sized (5-8”) crappie

should also be high (Figure 6).

About the Fish...

y = 0.0003x3.4237

R² = 0.9954

y = 0.0002x3.4651

R² = 0.9947

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 11.0 12.0 13.0 14.0 15.0

Wei

gh

t (

lb)

Total Length (in)

Black

crappie

White

crappie

M P

Q S

Master Angler Award

North Sterling Reservoir LAST UPDATED: JANUARY 2016

FISH SURVEY AND MANAGEMENT DATA Mandi Brandt - Aquatic Biologist (Brush)

[email protected]

About the Fish... Channel catfish Approximately 428,000 channel catfish

have been stocked since 2004. Regard-

less of stocking rates, low numbers of

channel catfish are sampled in nets dur-

ing annual surveys. The 11 channel cat-

fish sampled during the 2015 annual

survey were 17.93” long and weighed

2.37 lbs on average, with the largest fish

measuring 24.33” and weighing 5.63 lbs

(Table 2). Though few channel catfish

are typically caught in nets, the lower

numbers of fish caught in 2012 and 2013

compared to 2011 indicate the 2012 fish

kill negatively impacted the channel

catfish population (Table 1). Despite

this negative impact, fishing for channel

catfish was good during 2015. In an ef-

fort to gain a better understanding of the channel catfish population, a catfish project was performed in

2015. Results from this project indicated that the channel catfish population is composed of several size

classes, and that there is a large number of fish 17-23” long (Figures 7-8). The largest fish caught during the

project measured 36.26” and weighed 24.10lbs. Channel catfish fishing should be great during the 2016

fishing season.

0

2

4

6

8

10

12

14

6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38

Nu

mb

er C

au

gh

t

Total Length (in)

Figure 7. Length-frequencies of channel catfish caught during the

2015 channel catfish project at North Sterling Reservoir.

36.3 in; 24.10 lb

North Sterling Reservoir LAST UPDATED: JANUARY 2016

FISH SURVEY AND MANAGEMENT DATA Mandi Brandt - Aquatic Biologist (Brush)

[email protected]

About the Fish... Channel catfish

y = 5E-05x3.6351

R² = 0.9856

0

5

10

15

20

25

30

0 5 10 15 20 25 30 35 40 45

Wei

gh

t (

lb)

Total Length (in)

Figure 8. Length-weight regres-

sion for channel catfish caught

during the 2015 channel catfish

project at North Sterling Reser-

voir.

North Sterling Reservoir LAST UPDATED: JANUARY 2016

FISH SURVEY AND MANAGEMENT DATA Mandi Brandt - Aquatic Biologist (Brush)

[email protected]

About the Anglers...

2011 North Sterling Reservoir creel survey According to the 2011 creel survey, almost

6,200 anglers fished North Sterling Reservoir

for nearly 21,000 hours between May and

September of 2011 (Table 2). Ninety-eight

percent of anglers were Colorado residents,

of which 42% were from nearby towns in the

six surrounding counties (Logan, Sedgwick,

Phillips, Yuma, Washington, and Morgan).

Non-resident anglers were from Nebraska,

Wyoming, Utah, California, Minnesota,

and Michigan. The majority of anglers

fished with bait (75%), followed by

lures (14%), or a combination of

the two (10%). The remainder of

anglers fished with flies. Over one-

half of anglers targeted wiper

(Figure 11). Walleye and saugeye

were also highly sought after (Figure

11). Nearly 17,500 fish (all species

included) were caught, of which

approximately 43% were kept

and 57% were released. In

general, most anglers

enjoyed their fishing

trips at North

Sterling

Reservoir,

ranking their trip

quality as either

excellent (11%), good

(40%), or average (31%).

Likewise, most anglers approved of the fish they caught,

ranking fish quality as either excellent (22%), good

(56%), or average ( 21%).

Figure 9. Fish species targeted by anglers during

the 2011 North Sterling Reservoir creel survey.

Wiper

Walleye/Saugeye

Channel catfish

Trout

Black crappie

Other

54% 20%

North Sterling Reservoir LAST UPDATED: JANUARY 2016

FISH SURVEY AND MANAGEMENT DATA Mandi Brandt - Aquatic Biologist (Brush)

[email protected]

About the Anglers...

Shore anglers Boat anglers Total (all anglers)

9124 11687 20808

2356 3831 6187

8801 8648 17449

4741 2738 7479

4060 5911 9970

0.96 0.74 0.84

0.52 0.23 0.36

0.45 0.51 0.48

3.87 3.05 3.36

RETURNED CATCH (# OF FISH)

TOTAL CATCH/HR (# FISH/HR)

KEPT CATCH/HR (# FISH/HR)

RETURN CATCH/HR (# FISH/HR)

AVERAGE COMPLETED TRIP LENGTH (HRS)

Statistic

Estimates

FISHERMAN-HOURS (# of HRS FISHED)

FISHERMAN (# OF ANGLERS)

TOTAL CATCH (# OF FISH)

KEPT CATCH (# OF FISH)

Table 3. North Sterling Reservoir creel survey summary (May through September of 2011).

2011 North Sterling Reservoir creel survey continued...

North Sterling Reservoir LAST UPDATED: JANUARY 2016

FISH SURVEY AND MANAGEMENT DATA Mandi Brandt - Aquatic Biologist (Brush)

[email protected]

About the Anglers...

1)

2)

37%

38%

20%

3%2%

A B C D E

40%

43%

6%3% 8%

A B C D E

80%

9%

5% 2% 4%

A B C D E3)

Thank you to all of the anglers who were willing to participate in the creel survey!

2011 North Sterling Reservoir creel survey continued... Anglers were asked the following three questions and had

the following responses:

1) Using the following scale, please rank your support (or

not) for the future stocking of white bass in North Sterling

Reservoir?

A) Strongly support stocking

B) Support stocking

C) It does not matter one way or the other

D) Do not support stocking

E) Strongly against stocking

2) Of the following warmwater fish species, which would you

most like to catch at North Sterling Reservoir?

A) Walleye/Saugeye

B) Wiper

C) White bass

D) Yellow perch

E) Crappie (black and/or white)

3) What percentage of your angling time today did you

spend actively targetting trout?

A) 0%

B) 1-32%

C) 33-65%

D) 66-99%

E) 100%

North Sterling Reservoir LAST UPDATED: JANUARY 2016

FISH SURVEY AND MANAGEMENT DATA Mandi Brandt - Aquatic Biologist (Brush)

[email protected]

Master Angler Awards Year Species Length Angler name

2013 Common carp 31" Hunter Jones

2011 Channel catfish 31" Sarah Vogel

2011 Channel catfish 30" Charlie Vogel

2011 Blue catfish 30 1/2" Charlie Vogel

2010 Channel catfish 33" Tim Ludgate

2010 Channel catfish 30 1/2" Hunter Ludgate

2009 Largemouth bass 20" Brian McLain

2008 Channel catfish 32" Drake Ludgate

2008 Channel catfish 30 3/4" Will Wilcox