Birdemic/WMG

Birdemic and The Happening occur in the same universe.
On the east coast of the United States (and in France), pollution causes the plants to mutate to release a deadly neurotoxin that causes people to kill themselves. But on the west coast of the States, the same pollution mutates the birds so that they become Made of Explodium and gain acid spit. Both events happen at around the same time, which is why we don't hear of one in the other - both sets of protagonists are on the run for the most part, and the news stations are too busy reporting about their own areas to worry about what's happening in the rest of the world.

Alternatively, Birdemic occurs in the same universe as The Room.
Five years after Johnny's suicide, Denny's made a pretty good living for himself - he changed his name to Rod to get a fresh start, and he got a stable job as a software salesman. But as soon as he sees Nathalie in the diner, he's instantly reminded of Lisa, his first crush - so he runs after her, makes up a lie about them going to school together, and basically acts like a huge creeper. Nathalie originally goes on a date with him out of pity, but they find themselves genuinely attracted to one another, and it's The Power of Love that allows them to get through the Birdemic. The rest of the cast of The Room dies in the Birdemic, except for Mark, who moved away to get away from Lisa - he later became a playwright, and wrote and starred in a production of Johnny's life, called "The Room".

Rod is a Terminator that was sent to prevent the Birdemic.
He came from the future with the secrets of cheap and effective solar power as part of the plan to stem the exploding bird apocalypse, but his difficulties in properly emulating human behavior cost him valuable time.