Causes and symptoms. Fatigue may be the result of one or more environmental causes such as inadequate rest, improper diet, work and home stressors, or poor physical conditioning, or one symptom of a chronic medical condition or disease process in the body.
1 A hummingbird will use its tongue to lap up nectar from flowers and feeders. 2  A hummingbird's tongue is grooved like the shape of a W. 3  Hummingbirds have tiny hairs on the tip of the tongue to help lap up nectar.
Wasps, hornets, and yellow jackets are more likely to be attracted to a hummingbird feeder with old nectar in it. Another option is to get a hummingbird feeder with bee guards built in. The hummingbird can reach through to drink nectar, but the bees cannot.