An extraordinary birding experience in Olhão

There are numerous check lists and relationship guides for couples setting up home together, covering everything from household expenses to the where and why. Not that I have ever looked at them, apart from a few seconds ago for the purposes of this post! And I suspect our neighbours opposite haven’t looked at them either as not only do they not need to worry about the expenses, but it is quite evident they have come together for the purposes of procreation. Plus of course our neighbours opposite are European White Storks and Ciconia Ciconia don’t have access to the internet!

It took the female quite a while to agree to the ‘where’ they were going to live together. There’s been a male hanging around this chimney on and off for the six years we’ve been coming to Olhão but it wasn’t until last year the one became two.

Nothing happened though, and so we assumed that whilst the location of the chimney was perfect the chimney itself was less than perfect, Probably too wide for them to create a nest on.

However then in February this year, through the magic of stork engineering they had found a way to build. It was so exciting especially as initially all seemed to be going quite while well with the daily additions (mostly by the male) of twigs, sticks, grass and other items to the nest.

Then disaster struck. Strong winds in mid February resulted in the nest disappearing. Was that it we wondered? Fortunately not as within a couple of days the nest returned looking bigger than ever, and they were mating frequently. Apparently stork copulations can reach 160 in the first weeks, with a frequency up to 2 times per hour!

A week ago I spotted the female had begun to sit on the nest for extended periods of time. Had she laid the first egg? If so then we might be lucky enough to see them hatch as eggs are laid every other day and the incubation period is around 33days, which means we could still be their neighbours when hatching begins. How exciting!

Could it get any more exciting before the hatching I wondered though. To my surprise the answer is yes!

What we hadn’t realised until two days ago is that European White Storks, whilst incredibly gregarious and regularly seen by us feeding and nesting in large colonies, fiercely defend their nest territories. Apparently the size of the territory depends on the number of storks in the area; ie it might literally be the nest itself in a colony or as much as hundreds of metres for an isolated nest. The reason they need to defend is that storks will steal nesting materials from other nests and, even worse, storks without a secured nest of their own will attempt to take up home in occupied nests. It’s clearly a battle ground out there in the stork property market.

If you are worrying that it looks as thought it might violent, you’d be right to worry. I have since learnt from an excellent paper [Behaviour of the White Stork Ciconia ciconia: a review. Marcin Bocheński & Leszek Jerzak] that whilst interactions can be mostly gestures and ritual poses, they can also be violent, bloody, and deadly. Just take a look at my short video of a couple of minutes from Monday’s battle which includes both gestures (eg threat up-down display with wing pumping, nest covering with wings and forward threat display) and actual fighting between the males.

By the way were you as confused as us as to whom was who at times? Even watching the video again there are moments when I am uncertain. It was definitely our pair at the beginning, in the middle and again at the end, with the intruder I think arriving at least three times in these two minutes.

Fortunately our stork neighbours won this battle, and the whole event only lasted about half hour or so. They can last all day if an intruder is really determined. Must get incredibly exhausting as it isn’t just the physical interactions on the nest, there are all the numerous moments flying on and off the nest, and then all the affirmation clattering in between. Here are my still photographs from earlier on in the battle.

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Unfortunately I cannot confirm whether they have won this property war outright. We have observed more fly pasts by other storks this week, resulting in yet more defensive gestures and poses by our pair. I am sure the female wasn’t warned there might be regular fights when she moved in here!

There have though also been quiet periods, and both the female and male are regularly sitting on the nest. So hopefully that means there are eggs and fingers crossed there will be no more battles with intruders. However I cannot make any guarantees about the future. Incubation and the first few weeks after hatching are critical periods. And it is not just intruders the youngsters will need to worry about, there is also the risk of parental infanticide, another common behavioural trait of storks. Read the ‘Behaviour of the White Stork’ if you want to know more about that!

Whatever the future holds though, it has made a rather fascinating post today, and even if I say so myself as challenge host both of my square galleries above are excellent entries for this month’s spiky challenge! If chicks do hatch before we leave at the end of April I will share a second post on our neighbours, for now though let me finish with my lovely shot of the happy couple in their first home.

Technical info on the stork behaviour taken from: Bocheński, Marcin & Jerzak, L & Tryjanowski, Piotr & Sparks, T.H.. (2006). Behaviour of the white stork Ciconia ciconia: a review. The White Stork in Poland: Studies in Biology, Ecology and Conservation. 301-330