Mallard early nesting explained
Greg Allan, of Pleasant Point, asked:
On opening day of the duck season in South Canterbury, I was surprised that one mallard had eggs inside her. In 40 years of duckshooting this is the first time for this. Is this unusual for this time of year?
Jennifer Sheppard, an ecologist and research scientist at the University of Auckland, responded:
In 201415, I collaborated with Fish and Game to study mallard productivity in the Waikato and Southland regions. As part of this project, we radiomarked and tracked prebreeding mallards to determine when nesting would begin. We monitored 241 females, and the earliest nests we found were initiated on July 15 (date when the first egg was laid), although we did find a nest of an unmarked female that was initiated on July 5 in Southland. However, most birds initiated their first nests at the end of August.
You may recall that we had drought or droughtlike conditions in 2014 and 2015, so environmental conditions during our study were not ideal. We have seen a lot of rain these past couple of years, and birds appear to be in very good condition at the moment, which is most likely a result of abundant food sources associated with the excess rainfall we have seen. Captive and nonmigratory mallards are capable of nesting yearround, if they are kept in good condition. In New Zealand, many farmers have reported seeing mallards nest as early as March, and ducklings have been reported in April.
In answer to your question, finding eggs in female mallards during the May hunting season is not common, but it is certainly not unheard of. I believe it is indicative of very abundant food sources, which result in ideal breeding conditions. If we continue to get high rainfall events during summer and early autumn, it’s possible that shooting nesting hens during the hunting season will become more commonplace. Because of this, and the fact that female survival is important to population growth, we advocate that hunters ‘‘go for green’’ and try to let the hens pass.
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