A biologist sets up cameras to record all the animals that come to a watering hole over a 30 day period. This is an example of what kind of statistical study? Experiment Observational Study Survey

This is an example of observational study, because the biologist is not interfering or interacting with the subjects of study but just watching and registering data (recording with cameras).

The biologist is not conducting an experiment because (he is not setting up special conditions to register different responses to drive conclusions), and the biologist is not making any survey (questionnaires for example).

Answer: observational study