What is the Bird Jam?

Basically a jam dedicated to works featuring birds hosted during November [+/- a few hours to start at 1st of November UTC+14 and end at 31st UTC-12]. Either a lot of them or just some that are of great importance to the story. They could be even side characters or just mentioned somewhere as long as they're significant, somewhat.

Rules

1. The work must be a game and feature birds in some way, be it text, art, some extras and so on.
2. Your game should be free at least for a few weeks after the jam ends so everyone who took part can play it. You're free to make it paid later on, though.
3. You can start working before the jam starts or finish older projects, the goal is to have something playable by the time the jam ends.
4. Demos are fine, narrative based games are encouraged.
5. You're free to make the game 18+ for whatever reason but always add appropriate warnings.
6. There are no prizes. Everyone who finished their project is a winner.
7. Have fun :D

How much birb is enough birb?

Depends on your project? It's important for birds to have some role in the story, even if they're not main characters nor look like birds. And so almost anything goes. Government drones? Sure. Alien killer birds in human meatsuits trying to overtake the planet? Why not. Gijinkas or slightly anthro birds that look mostly like humans? By all means. Normal, realistic birds doing realistic bird stuff? Of course.  Killer geese? Always. Furry but for birds? Yeah. Some humans that study birds, bird gods, legends or whatever else? No problem.  Bird monsters, protobirds or pterosaurs? Not sure why you would do that but sounds good.

It's all very broad so you're basically limited only by your imagination.

What engines to use?

Whichever you want, honestly. Though considering most of the submissions would have some kind of story to tell, here are some recommendations:

Ren'Py - Basically the go to program for English language visual novel creators. Moderately simple and very easy to learn if you want a basic game. Just a bit complicated if you want something good looking or fancy and if you know what you're doing, you could honestly even make an RPG there since it's based on python; point&click games are easier, though. 
Unity - very versatile, has a big community and if you're stuck, looking for help shouldn't be hard. Can be used for both visual novels, text adventures [there are also way simpler and lighter programs for that, though] and something complicated.
Twine - want to write some interactive fiction instead? Twine is a very intuitive option that also allows its users to insert pictures or music to their stories [that requires easy to find plugins]. No GUI to customise needed, just write your story.
Quest - prefer text adventures? Look no more. Another very simple program, also offers to make your game online and post it on the site. You can also try Squiffy from the same creators [interactive fiction only].
Ink - another simple way to create interactive fiction. The end result is very light-weight since if you want, you honestly can pack the whole story into a single html file.
LÖVE - a bit more complicated  since it requires some programming knowledge. Uses Lua and is a framework for 2D games. Quick to learn. The only downside is that you have no basic art assets and need to prepare everything yourself.

Additional info

DevTalk - while not directly related to the creation nor hosting of this jam, it's a helpful community [on Discord] for visual novel creators that also makes finding group members for future jams easier.