Male songbirds such as the blue tit, Cyanistes caeruleus, adapt their parental behavior depending on individual and environmental factors. In a recent paper published in the Behavioral Ecology and Sociobiology journal, scientists discovered that blue tit fathers change their level of parental involvement depending on current conditions.
Blue tit mothers need to stay in the nest in order to incubate the eggs. The fathers normally feed the mothers twice an hour, bringing food so that she doesn’t have to leave. This partnership is necessary to successfully hatch and raise the chick embryos.
Researchers from the University of Groningen and the Behbahan Khatam Alanbia University of Technology studied 91 nests during the 2014 breeding season. They placed equipment in each nest to track temperature changes. In 63 nests, the researchers also set up infrared cameras in order to study male feeding behavior. They found that the male tits slowed down their feeding rates when environmental temperatures were high. The fathers also became more relaxed about feeding schedules when there were many fruit-bearing trees in the area. On the other hand, they were much more attentive if their partner was young and inexperienced.
The authors believe that the males slack off in warmer weather because the nest will require less incubation at higher air temperatures. This allows the mother to leave on brief trips where she’s able to feed herself. Similarly, the males don’t need to spend as much time finding food if there’s an abundance of fruit nearby. There was one case where the males increased feeding behavior. The males fed females more often if they were new mothers. This let the inexperienced mothers spend more time tending to the nest, though the authors note that the mother’s attentiveness didn’t actually affect incubation temperatures. The age of the male didn’t influence parental behavior.
Blue tit fathers switched their parenting style depending on the temperature, food availability, and the age of their partner. These findings are important for understanding incubation and parental behavior in songbirds and other animals.
Seyed Mehdi Amininasab et al. The effect of ambient temperature, habitat quality and individual age on incubation behaviour and incubation feeding in a socially monogamous songbird. Behavioral Ecology and Sociobiology (2016).