Thank you for that information. so dogs will lay in the ground if they are too hot or if they are too cold as the earth around them keeps them warm in the cooler months as well. If he feels cool in the winter which causes him to dig I would have his thyroid checked as hypothyroidism would show him having trouble with keeping a correct body temperature and the Golden is prone to this disease.
Toys are great, but like kids, dogs get bored with them and they become old really quick. If you recycle them like we used to do for our kids then that may help. Put some away for a while, and bring them out in a week or two and put the other toys away etc. A rotation.Also pick mind stimulating toys. Toys like kongs stuffed with cream cheese or peanut butter, the treat dispensing ball only put his daily dose of kibble in there, buster cube, nylabone there are so many that are mind stimulating. Regular balls, treats, squeak toys don't do much to stimulate the mind as there is nothing for the dog to figure out. If you are suppling mind stimulating toys then just rotate and add a new one in now and then.
Although you think that the dog has plenty to do especially with another dog there, this breed yearns for human attention. they would rather be with a human doing nothing than in a yard playing with another dog all day. Short bursts yeah, they'll do that but this is a breed that was bred with a job in mind which is retrieval and when they mind is not stimulated they can find trouble. If you get a treat dispensing ball pick up all other kibble or weight will be an issue, just fill the ball with kibble and assume that the pug will snatch a few pieces as well so factor that in with the pugs meal.
So have the thyroid tested (blood test) rejuvenate the toys and if needed get on line and check out mind stimulating toys for dogs. New ones come out everyday.
Train, train, and train in obedience as much as you can during the day, even if it is only ten minutes that you can spare. Nothing works a dogs mind more than a quick training session.
Teach the dog how to use a sand box. Get a kids sandbox and fill it with similar soil as your lawn, hide some biscuits and new toys in there so he realizes that if he digs there he finds interesting things.
Putting Chicken wire just under the soil where he is digging can help as will putting landscaping rocks around. You want the bigger rocks not the pea gravel, rocks that are about an inch or two and don't get the smooth edged ones, get the ones that are a bit pointy as dogs don't usually like to walk on that.
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