Controlling cats as bird predators

["Philip Veerman" <>]

I'm curious about this "keeping cats in at night" issue. Why at night? Is this 
for the safety of birds or maybe small native mammals or safety of cats from 
cars etc? As bird predators I would think that cats are as much or more 
dangerous to birds during the day as at night. On the basis that most birds are 
day active, so cats being mostly visual predators, are better able to hunt 
birds during the daytime than at night. I have not seen this book. I don't have 
evidence either way. Does anyone?

Philip