Recent changes in the diet and survival of Atlantic puffin chicks in the face of climate change and commercial fishing in midcoast Maine, USA

We examined the diet of Atlantic puffin ( Fratercula arctica) chicks at three midcoast Maine, USA, colonies during the years 2005–2014 and found that the puffins at each island have a distinct diet that has changed in recent years. White hake ( Urophycis tenuis) is by far the most frequently delivered prey at each island. Atlantic herring ( Clupea harengus) is the second most frequently delivered food, but has declined in recent years on two islands. In contrast, butterfish ( Poronotus triacanthus), haddock ( Melanogrammus aeglefinus), and redfish ( Sebastes spp.) have increased in the puffin diet on all islands. Chick condition declined significantly from 1993 to 2009. We demonstrate that puffin chicks with greater body weight experience a higher chance of postfledging survival as compared to chicks with lower body weight. The years 2012–2013 were a period of extreme sea surface warming, in which puffin hatching success and productivity sharply declined. This study provides new insight into changes in marine communities, examining changes in chick diet. We discuss our findings in relation to warming sea surface temperatures, recent climate-related decline in puffin productivity in the Gulf of Maine, and the impact of commercial fisheries on forage fish.