Sexual Dimorphism

This pair of  White-breasted Nuthatches was captured in a mist net near  Marvelwood's bird feeder on September 20, 2010. Notice the darker head and feathers in the male in the top picture; compared with the duller head and feathers of the female below. 

This is called sexual dimorphism.

Bald Eagle Sighting - Housatonic River

Nick Beck's first bird sighting in Ornithology during lab this afternoon (9/28/10) was a Bald Eagle!