Presuming you are filling your bird bath with tap water this will have all sorts of chemicals in it especially where you live - when our son was living in Cambridgeshire we had to use bottled water to drink when we visited him. The water in the pond will, at least in part, be rain water and therefore not have all the chemicals.

The tap water in Moray is very lightly treated but our two cats still prefer to drink from the pond or a muddy puddle to their water bowl any day of the week.

Also, a garden pond is a more natural environment for the birds. If you were a timid, wild creature would you prefer to drink from an open, round dish sitting on top of a pillar in the air or would you prefer something on the ground with some grass, plants and stones round it?

Moongrower ,I Always top up my bird baths with water from the water butt, so Never use tap water .I have lived in Cambridgeshire all my life , and have Never had to buy bottled water , tap water has always been ok.So cant understand why you found the water so bad when visiting your son , to have to buy it.

The water taste absolutely disgusting! It is so full of chemicals as to be unreal... The family filtered and used in tea and other hot drinks but to drink the actual water - all bottled. Perhaps it depends where you live in Cambridgeshire.

Bulba has also likely pointed you at the reason the birds prefer the pond - a much safer space for them and, unless you are emptying and cleaning the bird bath regularly it will rapidly become rather unpleasant.

Is your bird bath in an exposed area - where, for example a sparrowhawk could swoop through and catch a meal?

All that said animals and birds drink where they want to drink.

Thanks for all your comments .