12.1. Introduction

Foraging honey bees are exposed to various environmental stressors. Their flight performance can therefore indicate noxious influences. Basic parameters for estimating stress are forager longevity and foraging success as indicated by foraging activity, time spent outside the hive and ability to return to the colony. Most of these parameters require detailed observation and bees often need to be labelled individually. These methods are time-consuming and expensive. However, a number of approaches register honey bee flight automatically or use simplified test paradigms. We here discuss how to monitor flight activity of unmarked or individually marked honey bees.