In the winter of 1993 - 1994, the eye disease affecting House Finches was first observed in the Washington, DC area.  The disease is caused by the pathogen Mycoplasma gallisepticum, and is commonly referred to as 'conjunctivitis'.  In this paper, Lab scientists used FeederWatch data from 1994 - 1997 to track the rapid spread of this disease through the eastern House Finch population.   They described the progress of the disease, and seasonal fluctuations in where it was found.  The epidemic first spread north, probably carried by House Finches migrating north in spring.  The disease then spread south and west, and was reported in most of the eastern range of the House Finch by March 1997.  They found that the disease was most common in the fall.  The study documented that the disease caused significant declines in House Finch populations.

This article was written by Andre Dhondt, Diane Tessaglia and Roger Slothower of the Cornell Lab of Ornithology.  It appeared in the Journal of Wildlife Disease in 1998.