Increase in rusty birds

"Like a living thermometer, a small owl in Europe is turning a deep shade of red as climate change pushes temperatures ever higher," reports Michael Reilly of Discovery News. This owl, the Scops Owl, appears in two colors: gray and rusty red.

A group of researchers led by Paolo Galeotti of the University of Pavia in Italy have been observing changes in this owl's coloration from 1870 through 2007. According to this study, it appears that gray birds survive better in years when the climate is cool and rusty or red birds thrive better in warmer, wetter conditions. Since temperatures in Italy have been climbing an average of 1.1 degree Centigrade every 100 years, rusty owls have become more predominant and gray birds more rare.

Galeotti explained to Discovery News that red birds blend better in dense forests. He noted that the steady recovery of European forests may be the reason why more rusty birds are seen and less gray birds.

In the United States, another researcher, Frederick Gehlback of Baylor University noticed the same color tendencies in Eastern Screech Owls. These owls seem to stay in the rufus or red stage longer; the feathers of the rufus stage are more porous, dissipating body heat, while gray feathers are more "stout" and provide better protection against colder temperatures.

Both scientists were cautious, however, advising that it's still too soon to know whether climate is the only reason for this noticeable color change. There are many other factors in the owls' habitats that must be taken into consideration.

Source: "Owls getting redder as climate warms."