Table 4 (a) and (b) Simulated estimates of mean survival and realised fecundity of 1000 individuals, dependent upon population and maximum seaward migration distance (fjord zone; inner-, mid- and outer-fjord) for smolt (a) and veteran migrant (b) brown trout of Sognefjorden

(a) Salmo trutta smolts

Population

(Pop. survival rate: \(\Sigma {N}_{Surv}/N\))

Max migration extent

(Fjord zone)

N smolts (\({N}_{Start}\))

N survive

(\({N}_{Surv}\))

Max zone specific survival rate

(\({S}_{maxZ}= \frac{{N}_{Surv}}{{N}_{Start}}\))

Aurland

(0.447)

I

151

62

0.412

M

849

385

0.453

O

0

Lærdal

(0.521)

I

0

M

894

466

0.522

O

106

55

0.514

Årdal

(0.638)

I

0

M

740

471

0.637

O

260

167

0.641

Fortun

(0.754)

I

625

500

0.799

M

375

254

0.678

O

0

Mørkrid

(0.560)

I

855

516

0.603

M

145

44

0.303

O

0

(b) Veteran migrant Salmo trutta (mean values across years)

Population

(Pop. survival rate:

\(\Sigma {N}_{Surv}/N\) ± SD)

Max mig. extent

(Fjord zone)

N veteran migrants

(\({N}_{Start}\))

N survive

(\({N}_{Surv}\))

Est. fecundity ± SD

(\(\overline{{Fec }_{TL}}\))

Max zone specific survival

(\({S}_{maxZ}= \frac{{N}_{Surv}}{{N}_{Start}}\))

Realised individual fecundity

\((\overline{{Fec }_{TL}}\)* \({S}_{maxZ}\))

Realised population fecundity (%)

\((\Sigma \overline{{Fec }_{TL}}\) * \({N}_{Surv}\))

Aurland

(0.770 ± 0.001)

I

0

M

958

740

2,785 ± 18

0.772

2,151

2.1e⁶ (86.0)

O

42

30

11,298 ± 18

0.709

8,009

3.4e⁵ (14.0)

Lærdal

(0.680 ± 0.004)

I

181

100

843 ± 6

0.554

467

8.5e⁴ (4.2)

M

784

561

3,086 ± 22

0.716

2,208

1.7e⁶ (85.4)

O

35

19

11,208 ± 52

0.537

6,019

2.1e⁵ (10.4)

Årdal

(0.862 ± 0.001)

I

0

M

966

834

2,676 ± 13

0.863

2,311

2.2e⁶ (87.9)

O

34

28

11,009 ± 34

0.821

9,039

3.1e⁵ (12.1)

Fortun

(0.909 ± 0.002)

I

0

M

714

660

1,738 ± 4

0.924

1,606

1.1e⁶ (45.5)

O

286

250

5,509 ± 30

0.873

4,808

1.4e⁶ (54.5)