Bird weight loss or a lack of appetite should always be taken seriously. Since birds are generally small animals, any significant weight loss can mean a very serious health risk. Bird weight loss can be a key food-related signs that your bird is sick. If your bird begins eating less, either not finishing the food given to her or leaving more food than usual on the floor, contact your vet. It is very helpful, especially with a new bird, to keep a written record of how much and how often your bird eats, noting things like the amount of food given and amount left uneaten. You may not always notice a drop in appetite right away, but keeping a written food log like this can help identify potential problems sooner. Likewise, it is very helpful to weigh your bird regularly and keep a written record of his weight. Bird weight loss may not be always be readily apparent, since the weight loss can sometimes be disguised by ruffled feathers, another sign your bird is sick. A written log can prove extremely useful in identifying potential problems. Weigh your bird using a scale specifically designed for this purpose, if possible. If you cannot locate a bird scale, any small scale that measures in grams will usually suffice. It is important to weigh your bird in grams, since even portions of an ounce are too large a measure for many small birds. Weigh your bird at the same time each day, at least 3 times a week, and be sure to write down his weight. Just like humans, bird weights will vary each day by a small amount, usually not more than 1% to 1.5%. Whenever you notice bird weight loss, review the log to determine if there is a downward pattern of loss. A small loss one day, followed by a similar gain at the next weighing would not be a cause for concern. If your bird shows weight loss two weigh-ins in a row, begin weighing him on a daily basis. Bird weight loss that continues for three or more days, and any bird weight loss of more than 2% in a single weighing should be reported to your vet right away. Bird weight loss that is not attributable to normal daily fluctuations of around 1% should always be taken seriously. Even losing a few grams of weight can amount to a significant percent of a bird’s overall body weight. Bird weight loss of as much as 5% of a bird’s weight can be life-threatening. Weighing your bird regularly and keeping a daily log can help you quickly identify bird weight loss.