Do June temperatures affect the breeding success of Dark-bellied Brent GeeseBranta b. bernicla?

Abstract

In the 1950s and early 1960s there was a clear association between low June temperature along the coast of the Taimyr Peninsula and poor breeding success by Dark-breasted Brent Geese. More recently, as mean June temperatures have both fallen and become less variable, the association has weakened. A strong association remains between June temperatures in the Taimyr and changes in population size from one winter to the next. The great increase in numbers of Dark-breasted Brent Geese over the last 30 years, and especially during the 1970s, has been the result of lower mortality rates, rather than proportionate increases in the output of young. In years when few young have been produced adult survival has been high.