American macaw genus Anodorhynchus. Description The largest parrot by length in the world, the hyacinth macaw is long from the tip of its tail to the top of its head and weighs . Each wing is long. The tail is long and pointed. Its feathers are entirely blue, lighter above. However, the neck feathers can sometimes be slightly grey. The ring around the parrots eyes and area just underneath the beak are a strong, vibrant yellow. Ecology A main predator is the toco toucan, which consumes a large percentage of the eggs. Eggs are also regularly preyed on by corvids such as jays and crows, opossums, skunks and coatis. The young are parasitized by larvae of flies of the genus Philornis. Behaviour Food and feeding The majority of the hyacinth macaw diet is composed of the nuts from specific palm species, such as acuri and bocaiuva palms. They have very strong beaks for eating the kernels of hard nuts and seeds. Their strong beaks are even able to crack coconuts, the large brazil nut pods, and macadamia nuts. The birds also boast dry, smooth tongues with a bone inside them that makes them an effective tool for tapping into fruits. The acuri nut is so hard, the parrots cannot feed on it until it has passed through the digestive system of cattle. In addition, they eat fruits and other vegetable matter. The hyacinth macaw generally eats fruits, nuts, nectar, and various kinds of seeds. Also, they travel for the ripest of foods over a vast area. In the Pantanal, hyacinth macaws feed almost exclusively on the nuts of Acrocomia aculeata and Attalea phalerata palm trees. This behaviour was recorded by the English naturalist Henry Walter Bates in his 1863 book The Naturalist on the River Amazons, where he wrote that Charles Darwin remarked on Bates's account of the species, calling it a "splendid bird" with its "enormous beak" able to feed on these palm nuts. In captivity, the palm nuts native to the hyacinth macaw's natural habitat are often not readily available. In these circumstances the macadamia nut (which is native to Australia) is a suitable, nutritious and readily-accepted alternative. Coincidentally, the hyacinth macaw is one of the only birds with the necessary jaw strength to open the nut, which requires 300psi of pressure to crack the shell. Tool use Limited tool use has been observed in both wild and