Supporting Information
Appendix S1.
Growth.-The von Bertalanffy growth model (von Bertalanffy 1938) was used to estimate agestandard length growth curves using the following equation:
𝐸𝑞. 1 𝐿𝑡 = 𝐿∞ ∗ 1 − 𝑒 −𝑘(𝑡−𝑡0 )
where 𝐿𝑡 is the length at age t, 𝐿∞ is the asymptotic length, also known as the mean maximum
length, 𝑘 is the growth coefficient and 𝑡0 is the age where length = 0 (Ricker 1975). For growth
in weight, slope coefficients (b) of the weight-standard length relationship were extracted using a
power function and the von Bertalanffy growth model was applied to weight. We used
population-specific relationships between length and weight and calculated the von Bertalanffy
growth function for weight according to Ricker (1975):
𝐸𝑞. 2 𝑊𝑡 = 𝑊∞ ∗ [1 − 𝑒 −𝑘(𝑡−𝑡0 ) ]𝑏
where 𝑊𝑡 is the weight at age t, 𝑊∞ is the asymptotic weight, 𝑘 is the growth coefficient and 𝑡0
is the age where weight = 0. Growth in weight was analyzed in addition to growth in length
because of the ecological importance of mass and the differences in absolute and relative growth
for length and mass as fish mature (Van Den Avyle & Hayward 1999).
References
von Bertalanffy, L.. (1938) A quantitative theory of organic growth. Human Biology, 10, 181213.
Den Avyle, M. Van & Hayward, R.S. (1999) Dynamics of Exploited Fish Populations. Inland
Fisheries and Management in North America. pp. 127-166. American Fisheries Society,
Bethesda, Maryland, USA.
Ricker, W.E. (1975) Computation and Interpretation of Biological Statistics of Fish Populations
(Bulletin). The Blackburn Press.
Tables
Table S1. Linear correlations with lake Secchi depth. Results from linear correlations (Pearson)
between 5-year summer mean secchi depth and mean values of a suite of limnological,
bathymetric and biological variables. Column headings also indicate the 95% confidence
interval and P-value (P).
Parameter
Total Nitrogen (µg L-1)
Total Phosphorus (µg L-1)
Lake Area Above 5 Meters (%)
Daphnia Average Length (mm)
Daphnia Average Dry Mass (µg)
Lake Area Above 4 Meters (%)
Mean Lake Depth (m)
Lake Area Above 3 Meters (%)
Maximum Lake Depth (m)
Zooplankton Density (# L-1)
Lake Area Above 2 Meters (%)
Principal Component 2 (Zooplankton)
Lake Area Above 1 Meter (%)
Principal Component 1 (Fish)
Flushing Rate (Times per Year)
Chlorophyll-a (mg m3)
Zooplankton Average Dry Mass (µg)
Zooplankton Average Length (mm)
Hypolimnion DO (mg L-1)
Direct Drainage Area (Ha)
Perimeter (m)
Hypolimnion Temperature (°C)
Shoreline Sinuosity Index
Lake Area (m)
Principal Component 1 (Zooplankton)
Total Nitrogen:Total Phosphorus
Littoral Habitat (%)
Principal Component 2 (Fish)
Daphnia density (# L-1)
Lower Upper
Pearson
95%
95%
Correlation
CI
CI
-0.90
-0.98
-0.59
-0.82
-0.96
-0.33
-0.74
-0.94
-0.16
0.74
0.16
0.94
0.74
0.16
0.94
-0.71
-0.93
-0.09
0.69
0.05
0.93
-0.68
-0.93
-0.04
0.68
0.03
0.93
-0.66
-0.92
0.00
-0.66
-0.92
0.01
-0.65
-0.92
0.02
-0.63
-0.91
0.06
0.61
-0.09
0.91
-0.60
-0.91
0.10
-0.53
-0.88
0.20
0.51
-0.24
0.88
0.48
-0.27
0.87
0.45
-0.31
0.86
-0.45
-0.86
0.31
0.42
-0.34
0.85
-0.41
-0.84
0.35
0.39
-0.37
0.84
0.31
-0.44
0.81
-0.31
-0.81
0.45
0.26
-0.49
0.79
-0.23
-0.78
0.51
-0.19
-0.76
0.54
0.12
-0.59
0.73
P
0.01
0.01
0.02
0.02
0.02
0.03
0.04
0.04
0.04
0.05
0.05
0.06
0.07
0.08
0.09
0.14
0.17
0.19
0.22
0.23
0.27
0.27
0.30
0.41
0.42
0.49
0.55
0.63
0.76
Table S2. ANCOVA results for various fish traits associated with body shape, fin dimensions and trophic (feeding) ecology. Log
standard length (cm) was included as a main effect and interaction term. Where interaction terms are not significant, reported results
are from an analysis of variance with population source and log standard length as main effects.
Parameter
Body Shape and Fin Variation
Canonical Axis 1: Body Shape
Relative Warp 2: Body Shape
Relative Warp 5: Body Shape
Relative Warp 10: Body Shape
Body Depth
Caudal Filament Length (cm)
Pectoral Fin Length (cm)
Pelvic Fin Length (cm)
Caudal Peduncle Width (cm)
Wet Weight (g)
Trophic Morphology
Canonical Axis 1: Head Shape
Canonical Axis 2: Head Shape
Canonical Axis 3: Head Shape
Relative Warp 2: Head Shape
Relative Warp 1: Head Shape
Relative Warp 4: Head Shape
Mouth Width (cm)
Gape (cm)
Opercle Bone Length (cm)
Eye Width (cm)
Gill Raker Number
Gill Raker Length (mm)
Gill Raker Spacing (mm)
Gill Raker Width (mm)
n
Whole Model
F(19 or 10)
P
r2
Population Source
F(9)
P
r2
F(1)
Size
P
r2
F(9)
Source*Size
P
r2
1,520
1,520
1,520
1,520
1,520
1,520
1,520
1,520
1,520
1,520
350.7
157.4
42.9
61
7,440.5
702.1
2205.8
1749.2
724.8
12482.2
< 0.001
< 0.001
< 0.001
< 0.001
< 0.001
< 0.001
< 0.001
< 0.001
< 0.001
< 0.001
0.81
0.66
0.34
0.43
0.99
0.9
0.96
0.96
0.9
0.99
404.2
170
51.9
88.9
227
67.9
91.3
76.4
7.8
118.7
< 0.001
< 0.001
< 0.001
< 0.001
< 0.001
< 0.001
< 0.001
< 0.001
< 0.001
< 0.001
0.8
0.54
0.63
0.39
0.04
0.13
0.06
0.06
0.01
0.01
11
288.4
12.6
18.8
43040.7
3426
12240
9806.5
4207.9
73144.3
0.001
< 0.001
0.004
< 0.001
< 0.001
< 0.001
< 0.001
< 0.001
< 0.001
< 0.001
< 0.01
0.1
0.02
0.01
0.94
0.75
0.9
0.89
0.86
0.97
7.9
6.5
1
5.9
10.7
9
11.3
2.6
13
17
< 0.001
< 0.001
0.425
< 0.001
< 0.001
< 0.001
< 0.001
0.005
< 0.001
< 0.001
0.02
0.02
0
0.03
< 0.01
0.02
0.01
0
0.2
< 0.01
1,520
1,520
1,520
1,520
1,520
1,520
1,435
1,519
1,520
1,520
1,435
1,435
1,435
1,435
163.8
100.2
61.7
108.8
63
34.2
1275.3
1448.8
3553.8
728.7
25.7
809.3
67
599.4
< 0.001
< 0.001
< 0.001
< 0.001
< 0.001
< 0.001
< 0.001
< 0.001
< 0.001
< 0.001
< 0.001
< 0.001
< 0.001
< 0.001
0.67
0.55
0.43
0.57
0.43
0.29
0.94
0.95
0.98
0.9
0.16
0.92
0.48
0.89
84
132.6
2.7
137.4
102.8
4.9
49.8
36.8
42.2
72.5
28.5
15.6
22.5
50.4
< 0.001
< 0.001
0.101
< 0.001
< 0.001
0.028
< 0.001
< 0.001
< 0.001
< 0.001
< 0.001
< 0.001
< 0.001
< 0.001
0.6
0.45
0
0.54
0.32
0.26
0.04
0.04
0.02
0.11
0.16
0.03
0.21
0.09
188.1
0.1
79.4
21.9
50.9
32.8
9020.9
8489.7
20716.1
4477.5
3.4
4411.7
176.4
4060.2
< 0.001
0.864
< 0.001
< 0.001
< 0.001
< 0.001
< 0.001
< 0.001
< 0.001
< 0.001
0.067
< 0.001
< 0.001
< 0.001
0.03
< 0.01
0.41
0.01
0.07
0
0.89
0.91
0.96
0.78
0
0.88
0.19
0.77
10.6
3.3
4.3
5.1
6.2
3.3
6
2.8
1.2
4.7
0.9
4.4
7.8
19.5
< 0.001
< 0.001
< 0.001
< 0.001
< 0.001
< 0.001
< 0.001
0.003
0.26
< 0.001
0.52
< 0.001
< 0.001
< 0.001
0.03
0.1
0.02
0.02
0.04
0.03
0.01
< 0.01
0
0.01
0
0.01
0.07
0.03
Table S3. Proportional representation of prey in fish diets across lakes. The number of stomachs
analyzed and the number empty are indicated for each population. Prey values are population
means for each prey item represented as a proportion of each on a wet mass basis. Values in
parentheses are standard deviations.
Cold Stream
Brewer
Maranacook
North
East
Pushaw
Umbazooksus
Hermon
Unity
Merrymeeting
Average
# Analyzed
48
50
50
55
53
51
53
47
49
52
# Empty
40
10
3
2
2
3
15
8
25
24
Amphipoda
0.13 (0.35)
0.04 (0.16)
0.14 (0.29)
0.16 (0.22)
0.16 (0.31)
0.08 (0.19)
0
0
0.21 (0.36)
0
0.09
Fish
0
0
0.02 (0.14)
0
0.04 (0.19)
0.04 (0.17)
0.02 (0.15)
0
0
0.14 (0.35)
0.03
5
Benthic
Invert.
0.78 (0.41)
0.27 (0.40)
0.65 (0.42)
0.81 (0.25)
0.72 (0.40)
0.80 (0.31)
0.64 (0.46)
0.55 (0.45)
0.76 (0.38)
0.40 (0.49)
0.64
Daphnia
0
0.02 (0.07)
0.10 (0.25)
0.02 (0.14)
0.06 (0.24)
0.07 (0.21)
0.32 (0.44)
0
0
0
0.06
Other
Zooplankton
0
0.04 (0.17)
0.08 (0.17)
0
0.01 (0.07)
0.02 (0.05)
0.02 (0.05)
0.05 (0.14)
0
0
0.02
Terrestrial
0.09 (0.26)
0.64 (0.46)
0.02 (0.11)
0.01 (0.06)
0
0
0
0.40 (0.48)
0.02 (0.12)
0.46 (0.50)
0.16
Table S4. Results from AIC (corrected) model selection of white perch δ15N by individual traits
values. Results displayed are the top models with 6 or fewer parameters which best predicted
δ15N; more parameters were included initially, but additional parameters resulted in small (<
0.01) increases in r2.
Model
#
r2
AICc
Population, Raker Length, Length, CA 1
Population, Raker Length, Raker Width, Length, CA 1
Population, Raker Length, Raker Spacing, Length, CA 1
Population, Raker Length, Pelvic Fin Length, Length, CA 1
Population, Raker Length, Raker Width, Opercle Length, Length, CA 1
Population, Raker Length, Raker Width, Eye Width, Length, CA 1
Population, Raker Length, Raker Width, Raker Spacing, Length, CA 1
Population, Raker Length, Opercle Length, CA 1
Population, Raker Length, Mouth Width, CA 1
Population, Eye Width, CA 1
Population, Length, CA 1
Population, Mouth Width, CA 1
Population, Eye Width
Population, Raker Width
Population, CA 1
Population
CA 1
Mouth Width
4
5
5
5
6
6
6
4
4
3
3
3
2
2
2
1
1
1
0.73
0.73
0.73
0.73
0.73
0.73
0.73
0.72
0.72
0.71
0.71
0.70
0.68
0.68
0.68
0.65
0.31
0.16
535.69
535.97
537.34
537.44
537.52
537.66
537.89
541.36
542.88
551.76
552.63
553.59
567.59
568.38
570.78
588.59
743.22
791.38
6
Table S5. Results from a von Bertalanffy growth model for both length and weight where 𝐿𝑡 is
the length at age t, 𝐿∞ is the asymptotic length, also known as the mean maximum length, 𝑘 is
the growth coefficient, 𝑡0 is the age when length = 0 and 𝑏 is the slope of the length-weight
relationship. Model parameters for weight (W) are also reported.
Pond
Brewer
Cold Stream
East
Hermon
Maranacook
Merrymeeting
North
Pushaw
Umbazooksus
Unity
Pooled
n
L∞
k (L)
t0 (L)
W∞
k (W)
t0 (W)
b
51
47
51
45
49
48
46
47
48
45
477
33.75
37.33
35.56
19.70
22.83
27.10
23.90
24.99
40.85
22.34
29.99
0.08
0.06
0.11
0.18
0.16
0.16
0.23
0.15
0.07
0.12
0.11
-2.46
-4.28
-1.10
-2.03
-4.57
-1.64
-0.49
-1.76
-2.70
-3.61
-2.34
305.04
463.60
637.28
224.33
198.14
545.14
304.43
223.25
503.44
182.27
572.54
0.15
0.15
0.21
0.14
0.33
0.14
0.24
0.24
0.15
0.20
0.13
-0.93
-1.23
0.61
-3.02
-1.00
-1.93
-0.26
-0.79
-1.12
-1.10
-1.08
3.11
3.23
2.73
3.08
3.05
3.08
3.06
3.11
2.80
3.03
3.03
7
Table S6. Results from multivariate correlation between a suite of white perch morphological
traits from 10 populations. Correlations were calculated based on ANCOVA-derived LS Means.
Significant univariate correlations are indicated by ** (< 0.05) and * (< 0.10). Average
correlation is indicated in the last row.
Parameter
Canonical Axis 1
Pectoral Fin Length
Pelvic Fin Length
Caudal Fin Length
Mouth Gape
Mouth Width
Opercle Length
Raker Spacing
Raker Length
δ15N
Avg. Corr.
CA 1
1
0.70**
0.73**
0.64**
0.54*
0.62*
0.82**
0.51
0.83**
0.66**
0.69
Pect.
0.70**
1
0.86**
0.48
0.38
0.66**
0.32
0.21
0.65**
0.36
0.53
Pelv.
0.73**
0.86**
1
0.35
0.19
0.72**
0.32
0.40
0.66**
0.56*
0.54
Caud.
0.64**
0.48
0.35
1
0.82**
0.43
0.36
0.57
0.22
0.48
0.49
Gape
0.54*
0.38
0.19
0.82**
1
0.14
0.45
0.52
0.38
0.35
0.42
8
Mouth
0.62*
0.66**
0.72**
0.43
0.14
1
0.38
0.06
0.32
0.36
0.44
Oper.
0.82**
0.32
0.32
0.36
0.45
0.38
1
0.29
0.77**
0.46
0.48
Raker
S
0.51
0.21
0.40
0.57*
0.52
0.06
0.29
1
0.33
0.82**
0.40
Raker
L
0.83**
0.65**
0.66**
0.22
0.38
0.32
0.77**
0.33
1
0.47
0.53
δ15N
0.81**
0.55*
0.69**
0.53
0.41
0.62*
0.66**
0.67**
0.63*
1
0.62
Figures
Figure S1. Map showing the location of 9 lentic and 1 estuarine population (Merrymeeting Bay)
of white perch in the state of Maine, USA.
9
Figure S2. Outline of white perch showing 21 homologous landmarks used for multivariate
analysis of body and head shape. Landmarks were chosen to represent the body outline,
insertion of fins, dimensions of the operculum, depth of the caudal peduncle and position of the
mouth and maxilla.
10
Figure S3. Age-standard length (cm)/wet weight (g) von Bertalanffy growth curves for 10
populations of white perch.
11