swinging with playful birds singing chirping dancing playing.

from a wired article, 01-08-14:
orvids, the group of birds that includes ravens, crows, jays, and magpies, have quite the reputation. Ravens can use insight to solve problems, crows make and use a variety of tools, and jays can remember the past and plan for the future.

These birds are also known to be particularly explorative and playful. They are very interested in novel objects, regularly manipulating things they find and even taking and stashing objects. . . .Animals learn about their physical environment by interacting with objects, and corvids may build up a knowledge database of their world through object exploration. This might help them discover new sources of food, evade different kinds of predators, or adapt to changing or new environments. [Ivo] Jacobs says corvids fit this picture because they are relatively large-brained, long-lived, adaptable, playful, and innovative.
They are known for their behavioral flexibility and interest in new things. Object caching may reflect an exploratory spirit. . . .

—except from article by: Jacobs, I. F., Osvath, M., Osvath, H., Mioduszewska, B., von Bayern, A. M. P., and Kacelnik, A. (2013).