Toco toucans are recognized as the largest species in the toucan family and flaunt the biggest beak in regard to body size of all birds. This large yellow-orange colored beak with a distinct black marking at the tip of the bill is the most noticeable feature of R. toco. It accounts for one-twentieth of the total mass of the toucan, while also contributing to one-third of the bird's total length. Toco toucans weigh between 592 and 760 g, and average 61 cm in length. This species has what appears to be a blue iris, but is in fact a thin layer of skin that surrounds the eye. The blue circle is encompassed by an additional ring of orange skin that adds to the colorful physical appearance of toco toucans. Its basal metabolic rate is estimated at 8.72 cubed cm of oxygen per hour. Sexual dimorphism is present in this species of toucan. Measurements and observations reveal physical differences between males and females. Adult male toco toucans are typically larger than adult females. Juveniles are easily differentiated from the adults due to the young's duller colors and stubbier bill.
Range mass: 592 to 760 g.
Average length: 61 cm.
Average basal metabolic rate: 8.72 cm^3 oxygen/hour.
Other Physical Features: endothermic ; homoiothermic; bilateral symmetry
Sexual Dimorphism: male larger
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- Zoological Society of San Diego, 2010. "Toco Toucan" (On-line). Accessed February 12, 2010 at http://www.sandiegozoo.org/animalbytes/t-toucan.html.