From your description, I'm guessing that channel is a continuous covariate and your design matrix for psi looks like this:
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a1 a2
psi 1 channel
So, a1 is the intercept, and a2 is the effect of channel. The value of occupancy for a site will be:
psi(i) = exp(a1+a2*channel) / (1+exp(a1+a2*channel)).
A1 is the logit of occupancy when channel=0. Any sites in your data with channel=0 will have occupancy =
psi = exp(a1) / (1+exp(a1)) = 0.959. You can look at the 'real' estimates of psi for those sites to verify this.
Since A2 is positive (2.36), sites with a value of channel > 0 will have a higher occupancy estimate than sites with channel=0. Sites with channel < 0 will have a lower occupancy estimate than sites with channel=0. A plot of channel vs psi would be an line which increases as channel increases.
So, you don't interpret a1 and a2 as occupancy estimates. They are the estimated coefficients of the formula to compute occupancy at each site.