Sorry if this isn’t appropriate but I thought some might find it interesting -
We have a Haikubox in our yard and it seems to do a very good job of identifying birds, though it does not know we have a bluejay who is very good at imitating hawk vocalizations. 
2 Likes
I read something similar in IEEE: Birding At Night With a Plastic Dish and a Cheap Microphone - IEEE Spectrum
Really interesting. It’s not doable with Pickup because the hardware is designed for sensing sound levels, not frequencies, but it does set my mind thinking about other environmental activity that could be captured in small fluctuations in a sensor, perhaps in the flicker of a light sensor or vibration of the accelerometer. Generally, though, the environmental data we’re collecting requires sensors that don’t react quickly.