Nutrient composition of the diet of parent-raised kakapo nestlings | Notornis and Birds New Zealand

[摘要] The natural diet of the kakapo (Strigops habroptilus) is exclusively herbivorous. The bird breeds synchronously with the heavy fruiting or “masting” of certain plant species, including rimu (Dacrydium cupressinum), at intervals of 2 – 5 years, and did so in 2002 on Codfish Island (Whenua Hou) in southern New Zealand. Crop contents of kakapo chicks of 10 - 30 and 31 - 43 days of age, and samples of rimu fruit (entire fruit, red aril, green aril and seed) were collected and chemically analysed for dry matter, organic matter, crude protein, fatty acids, amino acids, fibre, simple sugars and minerals. The crop content samples contained predominantly carbohydrates (76 - 81 % by dry wt.), crude protein (7 - 13 %) and fatty acids (6 - 7 %). Entire rimu fruit contained 7.2 % crude protein, 10.9 % fatty acids, and 78 % carbohydrate predominantly of cellulose, hemicellulose and lignin. The red aril, green aril and seed nutrient composition were similar with the exception of the seed fatty acid profile. There was a large degree of similarity in the nutritional composition of the entire rimu fruit and the crop contents, supporting field observations of the time that female kakapo were feeding almost exclusively entire rimu fruit to their chicks. The nutrient profiles provide the first detailed descriptions of the diet of growing kakapo chicks which can guide the development of supplements and artificial rearing diets for this species. The diet of kakapo chicks up to 60 days of age appears to have a low concentration of essential nutrients and high indigestible matter content when compared with other species, consistent with specialised anatomical features and foraging behaviour of this parrot.

[学科分类] 动物科学

[关键词] chicks;crop content;growth rate;Kakapo;nutrient intake;rimu fruit;Strigops habroptilus