The internet has no shortage of videos of wildlife interfering with drone missions. More often than not, these videos result from the pilot doing something they shouldn't, but not always. I want to call attention to birds as they can be a real consideration for commercial drone pilots. Hawks, eagles and other birds of prey may see the drone as prey and strike from above at high speed. Conversely, other birds like crows, jays, and terns may see the drone as a predator and dive bomb it in an attempt to chase it away. Another danger is from a group of birds on the ground suddenly startled and colliding with the aircraft in a panic. This can also happen if you're flying under a bridge or awning where the birds (or bats) are nesting.
The key is to be vigilant and have a plan. Look for birds of prey riding the thermal updrafts. They often do this when they are hunting. Also, look for large nests, which could indicate birds of prey are in the area. Avoid the area if you can, but if you see one about to strike, "pulling up" may be your best strategy. The bird may not expect that as it is likely not what its prey would do. If your mission is in a nesting area, one or more birds may see your drone as a threat. They will likely fly close to the drone to investigate first and then start harassing it. A "curious bird" should be considered a significant risk. Best to land or move to a new location. There are always challenges when flying close to the ground. If you suspect birds are present, go slow at first and give the birds a chance to fly away. Be especially careful near water as that's a common place for flocks of birds to congregate. Again, the key to be aware of your surroundings, identify potential risks, and plan what to do.