This paper documents the median spring arrival date of 101 species of Maine migratory breeding birds in 2010 compared to their normal arrival from 1994–2011. The spring of 2010 was uniformly warmer for March, April, and May (monthly departures of 2.0 to 4.0 °C above the mean value). The 101 species showed a strong response to the warm spring, with 86 species arriving earlier, only 12 arriving later, and 3 showing no difference in arrival date from the 17-year median. The strongest response was by leaf-gleaning birds; all 30 species arrived earlier in 2010.