Of course it's OK.
But don't be suprised if you end up with an empty bird feeder.
There could be one of a number of reasons why your neighbour's feeding station is busier than yours and poaching her birds is probably not the solution for you.
A better solution might be for you to run a small study of what's different between your garden and your neighbours:
Do you - for example - both have ponds? Fresh water = life. This could be why your neighbour's bird feeder is alive with birds. When, how often and at what time of the day do you put food out for the birds? Once in a blue moon, or, every day? Does any of that really matter? Well...
More recently, we understand that birds are searching for food first thing in the morning; therefore, if you're filling your bird feeder in the afternoon and it's empty from, say, 7am until 2pm you're missing the main foraging activity. I feel that birds' activities are cyclical and repetitive i.e. if they find food at number Thirty three, it's a fair assessment to believe that birds believe that there's a good chance they'll find food there the next day and, when the do, and this happens enough times, the daily visit to number Thirty three becomes a habit. One that you won't break by moving your feeder closer.
What you can do, however, is to learn from what your neighbour's doing. Think about the three tenets many successful garden birders address - reliable supply of food, shelter and fresh water - and you'll be attracting your own garden guests in no time at all.
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