Owls Follow Up

This is where the Inter-Web thing is so amazing, following my posting on the owls I have a real expert responding. Thanks Romillyh.

The behaviour that I witnessed is unusual, not least because Tawny Owls do have a strong pair bond and the normally mate for life and more importantly hunt together as a pair. While out watching Badgers I have seen this in action where if one bird fails to make contact with the hunted prey, the second bird has made the kill. The first time I saw this I thought it was competition for prey, so it shows how careful an observer has to be basing interpretation upon one or a few observations.

This is why I recounted my observations as well as adding my speculations. As the new juvenile is not banded or marked, I can not know for sure that the “new” female is not one of the offspring of the established pair. However, as normally the parent birds do drive off all their brood, it is a reasonable assumption to make.

That said I also voiced some of my speculations as to what is happening. Is the new bird an insurance for a hard winter? The honest answer is I do not know, yet when I was much younger and talking to senior birders in the past this was an observed occurrence. It appeared to decrease as winters in Britain became less severe. Therefore while it may not have been recorded scientifically, older amateur observers recounted this happening. While this may be behaviour that was lost in the populations in the South East of England, it could be that in areas like the North East where winters are harder, this aspect of behaviour is retained. I fully realise that at the moment I am speculating. However based upon anecdotes and others observations and some educated guess work, it could be that I have seen something rare and seen only in populations where conditions create this behaviour.

Also while I have not heard reports of a male mating with more than one female in Tawny Owls, I have heard of Barn Owls. Also there are many species of birds that do this. It would only be likely if there is sufficient resources to keep two families. Again I am speculating and trying to ask questions that could explain the behaviour, but it could be that local conditions have ensured plentiful prey. This in turn may make it possible for the male to support two females.

It is one of the delights of observing wildlife that there is always something new to learn. In time further observations may help answer some of the questions I have. Other peoples observations also help in gaining a clear picture too. It may be that time will show that my speculations are incorrect, but at the very least the observations have sparked my curiosity and I may be able to answer some or all of my questions in time. Equally I may never get to know or understand what was happening. Either way these Owls provided a wonderful night of wildlife watching.