What might be a sign of illness in the brood within a hive?

Dead brood is a clear indicator of illness within the hive. When healthy, the brood should develop into young bees without mortality at this stage. The presence of dead brood can be a sign of several serious health issues, such as disease, parasites, or exposure to harmful chemicals. For instance, American foulbrood is a bacterial infection that can cause brood to die before it hatches, leading to noticeable dead pupae or larvae in the cells.

In contrast, a strong scent might indicate a healthy colony or suggest fermentation rather than illness, depending on the nature of the scent. The vibrancy of bees usually reflects a thriving and well-functioning hive, signaling good health rather than illness. Longer foraging times can be attributed to various environmental factors and are not a direct indicator of brood health.