The animal on the cover of R Packages is a kaka, or nestor parrot (Nestor meridionalis), found in native forests of New Zealand. Generally heard before they are seen, kaka are very gregarious and move in large flocks.

Kaka are obligate forest birds that obtain all their food from trees. They are adept fliers, capable of weaving through trunks and branches, and can cover long distances, including over water. They consume seeds, fruit, nectar, sap, honeydew, and tree-dwelling invertebrates.

Although forest clearance has destroyed all but a fraction of the kaka’s former habitat, the biggest threat to their survival is introduced mammalian predators, particularly the stoat, but also the brush-tailed possum.

Many of the animals on O’Reilly covers are endangered; all of them are important to the world. To learn more about how you can help, go to

The cover image is from Wood’s Animate Creation. The cover fonts are URW Typewriter and Guardian Sans. The text font is Adobe Minion Pro; the heading font is Adobe Myriad Condensed; and the code font is Dalton Maag’s Ubuntu Mono.

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