Ecological Archives
E087017A1
Darren W. Johnson. 2006. Density dependence in marine fish populations revealed at small and large spatial scales. Ecology 87:319–325.
Appendix A. Summary of linear, mixedeffects regressions used to test for overall presence of temporal density dependence in mortality of juvenile rockfish. Polynomial models were included to determine whether the relationship between mortality and density was significantly curvilinear, rather than linear. Data are presented for both the blue rockfish (Sebastes mystinus) and the KGB species complex (S. atrovirens, S. carnatus, and S. chrysomelas).



Value

SE

df

t value

P value

S. mystinus 
Full model

Intercept

0.4871

0.68133

16

0.7149

0.485



Density

0.05973

0.04943

16

1.2084

0.2445



Density^{2}

0.0003

0.00071

16

0.3519

0.7295










Reduced model

Intercept

0.641

0.501

17

1.267

0.222



Density

0.043

0.012

17

3.507

0.0027









KGB 
Full model

Intercept

1.8588

0.48478

16

3.8343

0.0015



Density

0.1372

0.03805

16

3.6067

0.0024



Density^{2}

0.001

0.00041

16

2.4221

0.0277









log(KGB) 

Intercept

2.533

0.437

17

5.78

<0.0001



log(density)

0.0489

0.012

17

3.97

0.001

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