Summer Pignic

Summer Pignic is the sixth holiday themed Angry Birds episode and the fourth episode in Season 2011, and as such, is available through Angry Birds Seasons. The setting is a field in the summer. The chapter was first announced on their Facebook page; and on June 20th, their Facebook profile picture announced the name. The episode was released at the beginning of the Summer Solstice on June 21st, 2011, and like Season's Greedings, each level is unlocked in an Advent-calendar fashion, and does not require the levels to be completed in order to access the others. This is the only episode to have space-themed levels, although there are only 2 (including one as a Golden Egg).

Storyline
The following is from The World of Angry Birds Official Guide, as told by the Mighty Eagle:

MAD HOGS GO OUT IN THE MIDDAY SUN

With the sun beating down, the birds thought they were safe on the grassy plains near the Golden Fields. Surely it was too hot for the pigs to go egg hunting? Wrong. King Pig doesn't care if his Minions sizzle in the sun. Distracted by a kite flying across the sky, Chuck took his eyes off the nest for a second and, well, you can guess what happened next.

Trivia

 * Summer Pignic is the first episode to be announced on Facebook.
 * It is also the first episode from Angry Birds Seasons to have official merchandise.
 * This episode is a play on the phrase, "summer picnic", as the pigs are having a picnic.
 * The clouds moving in the background take various shapes, for example, Red Birds and Pigs.
 * This is the first episode to be based on summer, the second being Piglantis.
 * For some reason, Level 17 on Summer Pignic is on the moon. There is a low gravity effect, and the player has 2 Black Birds and one White Bird. This would technically mean that this level is White Bird's first time in Space.
 * In Level 20, there's a Small Pig wearing a pink hair bow from Hogs and Kisses, and a Medium Pig wearing a green leprechaun hat from Go Green, Get Lucky.
 * In Level 30, King Pig wears a safari hat with a symbol of a crown, much like the Summer Pignic Short Movie.
 * Summer Pignic is the only Seasons episode to be themed on an actual season besides Piglantis, rather than holidays.
 * The Summer Pignic Surprise Video Stage and strategy are almost identical to Theme SP-30.
 * Some levels in the Summer Pignic episode change into space levels. This may be the reason why Rovio made Angry Birds Space.
 * One of the Golden Eggs is space themed too. Also, it has a "Samsung Galaxy S-II" block that is invulnerable.