Pines are coniferous (cone-bearing), needle-leaved trees, belonging to the Pinaceae family, and closely related to firs, cedars, spruces and other conifers. Pine trees grow primarily among their close relatives, in coniferous forests, especially those within the North Temperate Zone. There are over 100 species of pine, naturally occurring throughout parts of North America, Europe and Asia. And, with such a wide range, there are all sorts animals that inhabit pine trees.
One of the most common inhabitants, there are a multitude of different birds, including owls, hawks, eagles, thrushes, crows, jays and many other species, that nest in pine trees. Some of the more notable birds that live in pines are the bald eagle, great horned owl and American robin. Various woodpecker species actually live in hollowed out borrows, built into the trunks of pine trees, most often snags (standing dead trees).
While not near as many as birds, there are still a fair amount of mammals that live in pine trees. Squirrels are one of them most successful pine dwellers, and many species, including the tassel-eared squirrel, western grey squirrel and red squirrel (both American and Eurasian varieties), rely on the pine nut as a primary food source. Squirrels are known to nest in branches, as well as within hollows and abandoned woodpecker nests. A strictly European conifer inhabitant is the carnivorous pine marten, a relative of the weasel that often feeds on other pine-dwellers, like birds and squirrels. Other mammals that are often found living in pine trees are raccoons, opossums and porcupines. Even bobcats and lynxes will sometimes take naps or hide in pine branches.
Insects and Arachnids
Like most places on Earth, the insect population in pine trees dwarfs that of any other type of animal. Many types of spiders, bees and wasps sometimes build their respective webs, hives and nests in the branches of pines. However, most insects don't really nest in, as much as occupy, pine trees. Some types of insects that are commonly found in pine trees are mosquitos, ants, beetles, aphids, moths, dragonflies and butterflies. Arachnid inhabitants (aside form spiders) include scorpions, ticks and mites.
Amphibians and Reptiles
Since most coniferous forests contain relatively little humidity, there are not many cold-blooded animals that live in pine trees. Only a few species of tree frog, including the pine woods tree frog and grey tree frog, are known to sometimes live in pine trees, and only when located in very boggy areas. There are also a handful of arboreal lizards, mostly iguanids, which are sometimes found living in pine trees.