Amazon parrots are gluttons. They will sit in front of their food bowl and eat until the food is done. This gluttony predisposes them to obesity, especially when they are fed a diet of fatty seeds (sunflower, safflower, hemp, etc) and nuts. This obesity affects long term health and also fertility, as an obese bird may be unable to copulate, the fat in the abdominal cavity will put pressure on the gonads, deterring their full development, or, because health is compromised, they simply do not come into breeding condition. Monitoring the quality, volume and the fat content in the food and encouraging exercise are thus important.
The propensity of Amazon parrots towards obesity varies tremendously. This depends on the sedentary nature of the species and their size. As an example, the Yellow-lored Amazon Amazona xantholora rarely becomes overweight, as it is an active member of the genus. In contrast, the Yellow-naped (Amazona auropalliata) and Yellow-headed (Amazona oratrix) types can get overweight easily, as they are less inclined to fly and much more prone to climb. This active or sedentary nature not withstanding, I believe that all Amazons should be managed as a group that has a tendency to become overweight and the appropriate measures taken.
The guidelines we follow are simple:
1)Feed a low fat diet. We keep our Amazons outdoors in south Florida, where the climate is fairly benign. As a result, they do not need a high caloric intake in winter like they would in areas where the mercury declines. Because of this, we put them on a finch seed mix from November to January or February to induce weight loss should they have become fat during summer, when rich foods are given to encourage breeding; the cut off date depends on the species, as the Yellow-napes nest very early and the Caribbean species much later in the year. In cooler climates as soon as the deep of winter is over, the fat should be reduced to encourage shedding fat layers built to thermoregulate. I always recommend not feeding seed mixes rich in sunflower, safflower and hemp or nuts for obvious reasons; the exception is when they are sprouted, when hydrolysis coverts the fat in seeds to fatty acids and also more easily digestible nutrients. Instead we feed small seeds (millets of various types, wheat, buckwheat, oats, milo, etc) as a treat but keep the pairs on a pelleted mix, which comprises about 60% of the diet; the remaining 40% is made up primarily of vegetables and sprouting seeds.
2)Monitor food intake. There is a formula that a bird should consume about 10% of their body weight in food daily, but I have never relied on this calculation. This is because climate, age, level of activity and even breeding condition can all affect metabolism and consequently whether the food is used to add to the body weight or will be expended by normal bodily activities. Instead we feed enough so that the birds consume the entire amount in 15-20 minutes, then offer vegetables and a little fruit. We monitor the weight and increase or decrease the food that they get, reducing or increasing the amount fed. Pairs rearing young obviously receive much more food, as this is then used to feed the young. We never fill the bowl and let them eat and eat until they become so rotund that they roll across the cage.
3)Avoid feeding fruits, whose sugar content encourages the storage of body fat; instead feed vegetables, especially those rich in beta-carotene. These vegetables (carrot, pumpkin and sweet potatoes) are offered steamed, which breaks the fibers to give access to the important nutrients. We also use peas, broccoli, green leafy vegetables, cooked beets, hot peppers, fresh corn (horse corn, which is less sweet that the sugar packet sweet corn widely sold in many countries) and any other vegetable available at the grocer. The fruits we feed are heirloom varieties, which are low in sugar. We avoid feeding oranges, grapes and bananas, but do feed berries (especially those that are not very ripe, when the sugar content peaks), heirloom apples and an array of tropical fruit that we grow, which we feed long before they reach their peak in ripeness.
4)House pairs or groups in long flight cages (minimum 3.6 m, 12 ft) with perches at opposite ends to stimulate flying. Solid walls along the side can induce flying. By throwing enrichment away from the flock, one often encourages the birds to fly and reach the treat.
5)Provide enrichment to encourage activity that burns calories. Fresh branches, palm fronds, palm drupes, pinecones, split green coconuts and more can used to keep the birds busy for hours. This is important to burn energy and to encourage normal foraging behaviors.
6)Allow visualization of pairs until the commencement of the breeding season, as the males will often spend time displaying. This energy spent will induce gonadal development and is preferred over time spent at the food bowl. Once breeding commences, visualization should be blocked to prevent the hyper charged male from attacking his mate in his inability to initiate a fracas with the other male.
Insuring that a pair of Amazons is in proper condition is key to success, because a bird whose weight exceeds as little as 10% above the normal will be 31% less likely to produce viable eggs in data that we are amassing on a yearly basis. This data has shown why the effort to monitoring weight in Amazons is so vital to success.
author: Tony Silva
Title photo: (c) Lubomir Tomiska