Ants keep gathering around my dog. What can I do?

It’s ant season in Southern California and I have a 17 year old dachshund and no matter where he lays, ants keep invading his space! Last night I went to sleep and made sure there wasn’t any on or around him but when I woke up in the morning there was a trail and some just scattered around the blanket. We’ve washed him, his beds and blankets but they keep coming back. He doesn’t seem to be getting bit but I can’t imagine it being comfortable if they’re crawling on him. Anything I can do to prevent this?