Although they are common birds, they are very shy and very unobtrusive. They are mostly quiet but in their comfort zone they can get very musical and can launch into an eloquent song. I`ve just been reading about how its mostly the females that do the singing, for it is they who dictate the dynamics of the Dunnock’s weird sex life – for the Dunnocks are mostly polygamous.
Dunnocks, as a rule rather than an exception almost always have a (love) triangle going on, and mostly, it is one female pairing with two or sometimes even three males with proper commitment involved! and, its not on the sly, all of the participants are fully aware. Well, if that was weird, it gets even more so, because the males which are paired to a female are still free to pair up with other females, which in-turn are paired with another set of males and so on! It makes it sound like one big orgy, but there is a organised structure and logic to it.
As in the case of social mammals, there is constant fighting between the males resulting in a dominant alpha male whose position is always up for grabs from the other males. The reason why such relationships exist is thought to be because the female finds it easier to sign up a number of males to build her nest and in feeding her babies. It has also been found that the size of a females territory is directly proportional to the availability of food, the lesser the food the bigger her territory and as a result, more her number of males!
Finally, with so many males around, you`d think any one of them would pounce on a mating opportunity. However, during the courting display, the male will peck at the female’s cloaca until the female expels a drop of sperm from her previous mating. Only then will the new male mate with her!
As if the Dunnock`s sex life was not interesting enough, the Cuckoo adds an even more interesting twist in the tale: the Dunnock is one of the Cuckoo`s favourite victims. It will often remove one of the Dunnock’s eggs and lay one of its own there (see image here). When the young Cuckoo hatches, it will then proceed to remove other Dunnock eggs or even fledglings by pushing them out, (see image here)thereby gaining all the food and attention of its unknowing foster parents!
When they are not breeding, the Dunnocks are usually solitary but may for feeding groups when food is freely available. Up until recently, they were not known to feed from feeders and were thought to be more insectivorous. However, it is thought that Dunnock is facing severe pressures such as starvation, unfavourable weather, and predation (not to mention the cuckoos!) recently, causing them to adapt to more plentiful supply of food from feeders. When I first setup my feeder, I dint have any birds coming to it for almost a month. Then one fine day, I noticed my first bird guest– a Dunnock. It must have been desperate for food that winter. The Dunnock does lead an interesting life indeed and along with the fact that it was the first bird at my feeder , it will have a special place on my bird list.