Mark Forbes explains how Arctic sea ducks develop herd immunity from avian cholera
Herd immunity, when a threshold proportion of a population becomes immune to a disease-causing organism, reducing or stopping further transmission, is very much in the news. Avian cholera much less so. But there is an intersection between these two subjects that appears to have played out over eight summers between 2005 and 2012 at the largest colony of Arctic-nesting sea ducks, specifically Northern common eiders, in the Canadian Arctic.