I know the frog mating calls for all species of frogs in my area and volunteer for the local DNR to survey frog populations in my county. It's a good indicator of water quality.
I took a random amphibian research class as an elective, loved it, and still do it 20+ years later.
It's the Swedish bakers dozen so you can eat 3 raw eggs + shells on the way home and still have a dozen eggs to put in the fridge. It takes three eggs to equal the calories found in a small donut which is why the bakers dozen eggs is 15 instead of 13.