Rolf Nussbaumer / RF- American Robin (Turdus migratorius) male preening. Rocky Mountain National Park, Colorado, USA. June. (This image may be licensed either as rights managed or royalty free.)

Rolf Nussbaumer / RF- American robin (Turdus migratorius) female feeding in Black hawthorn (Crataegus douglasii). Grand Teton National Park, Wyoming, USA. (This image may be licensed either as rights managed or royalty...