1, thrush is the arch bridge mouth.
2. Artificial sand sticks are too profitable. If it is found that the income of the sand stick is too large, replace it with a stick without sand in time, or treat the sand stick, rinse the original sand stick with water, dry it and coat it with candle wax, or take it out and polish it with a millstone.
3, as long as it does not affect the bird's intake and does not pick and dig feed indiscriminately, it is more beneficial to fighting birds.