| avian reproductive failure in response to an extreme climatic event. | recently, climate change research has emphasized the potential increase in the frequency and severity of climatic extremes. we compared the reproductive effort and output among four species of passerine birds in coastal southern california, usa, a semi-arid region, during a normal precipitation year (2001) and the driest year in a 150-year climate record (2002). both reproductive effort and output differed dramatically between years. mean reproductive output among the four species was 2.37 fledg ... | 2005 | 15549403 |