Typical adult canary should be about 4 to 8 inches in height and weigh between .4 and 1 ounce. If you’re concerned that your canary is looking a little well rounded, contact your vet and schedule a basic checkup. Your vet can help you determine if your canary is over or under the average weight. Some solutions for overweight birds is to cut back on the amount of food and treats given daily. You should be using a canary seed formula for main feed. Read the package carefully for the recommended daily serving. If your feeding this amount and your bird looks too large then cut back a little each time. If your bird looks underweight then increase a little. Give your bird a few days to actually show any weight change. Again, talk with your vet Cherry Hill, NJ for exact diet instructions and details about your bird’s weight.