Table 4. Results of zero-inflated GLMs conducted for the abundance of bumble bees (a), syrphid flies (b), and non-syrphid flies (c).
(a) Bumble bee model
Variable Coefficient SE z value p value
Conditional model
Intercept -20.26 2.77 -7.3 <0.0001***
Day N 0.19 0.027 7.4 <0.0001***
Day N2 -4.29 ×10-4 6.3 ×10-5 -6.8 <0.0001***
Year (2018) -2.35 3.11 -0.75 0.45
Temperature 0.037 0.008 4.6 <0.0001***
Relative humidity -0.0058 0.0019 -3 0.0025 **
Day N × Year (2018) 0.043 0.030 1.5 0.15
Day N2 × Year (2018) -1.4 ×10-4 7.0 ×10-5 -1.8 0.059
Zero-inflate model
Intercept -2.56 0.29 -8.8 <0.0001***
(b) Syrphid fly model
Conditional model
Intercept 3.97 1.45 2.7 0.006 **
Day N 0.032 0.015 2.2 0.027 *
Day N2 -1.2 ×10-4 3.7 ×10-5 -3.2 0.0013 **
Year (2018) 10.38 1.74 6.0 <0.0001***
Temperature -0.057 0.0078 -7.3 <0.0001***
Relative humidity -0.036 0.0017 -21.3 <0.0001***
Day N × Year (2018) -0.12 0.018 -6.7 <0.0001***
Day N2 × Year (2018) 3.5 ×10-4 4.4 ×10-5 7.8 <0.0001***
Zero-inflate model
Intercept -3.67 0.47 -7.8 <0.0001***
(c) Non-syrphid fly model (c) Non-syrphid fly model
Conditional model
Intercept 19.3 0.91 21.1 <0.0001***
Day N -0.16 0.0094 -16.7 <0.0001***
Day N2 3.8 ×10-4 2.4 ×10-5 16.2 <0.0001***
Year (2018) 4.62 1.38 3.4 0.0008***
Temperature 0.0092 0.0056 1.6 0.10
Relative humidity -0.0092 0.0013 -7.3 <0.0001***
Day N × Year (2018) -0.068 0.014 -4.8 <0.0001***
Day N2 × Year (2018) 2.2 ×10-4 3.5 ×10-5 6.2 <0.0001***
Zero-inflate model
Intercept -5.3 1.00 -5.29 <0.0001***