Tuesday, 22 March 2016

Belgian Blackcap is still here.

The Belgian ringed Blackcap was still in the garden today but is starting to look very fat so could be about to depart. It is also singing more frequently and louder so is clearly getting into breeding condition too. Research has shown that Blackcaps that winter in the UK gain an advantage over those that winter in the Mediterranean and Africa by having a shorter return journey to the breeding grounds in central Europe. They also return a little earlier and are able to claim the best territories as a result and this in turn allows pairs to lay larger clutches and rear more young. Further reading on some of this research can be found here.

Judging by its appearance it has, or very nearly has, put on enough fat to make a non-stop flight back to its breeding grounds. This could be a journey of up to 1000km or 1200km and take around 24 hours.
It looks rather plump from this angle too.
Another garden regular is a rather scruffy looking Robin. It has numerous displaced feathers and has been like this for several weeks, if not longer. Initially I thought its appearance was due to fights with other Robins but it has had this scruffy appearance for far too long for that to be the case. It wouldn't have left displaced feathers after a fight and would have preened them back into place if it could. It has presumably sustained some damage to its skin that causes some of the feathers to grow out of the usual alignment. Perhaps it has been injured in a fight in the past or has had a close encounter with a predator, whatever the cause it can't preen the affected feathers back into place.

Scruffy Robin.
When I reviewed this photo on the back of the camera I zoomed in on the ring and could see it started with the letter V. This mean't it was a fairly old bird so I took enough photos to get the full ring number. The full number turned out to be V070535 and it was ringed in the garden on 16/02/2011 so would have hatched in 2010 or before. This makes it around 6 years old and possibly older so is quite a good age for a Robin. Looking at the current BTO Online ringing Report the oldest Robin recorded from UK ringing stands at 8 years, 4 months and 30 days.

It looks just as rough from the front.
Whatever the cause of its appearance it is a survivor and quite old for a Robin.
There are still at least a dozen Siskins visiting the feeders and chomping their way through large quantities of sunflower hearts. There may even be as many as 20 or 30 that visit the garden over the course of a day as the proportion of males and females and ringed and unringed birds changes throughout the day.

They remove the skin of the sunflower heart before breaking it into smaller pieces and eating it. If they drop the seed or any part of it during this process they simply take another if they are at a suspended feeder. If they are feeding on a bird table, like this bird, there is a chance they will finish off a seed they have dropped but they often just start again with a fresh seed.

I still haven't seen any summer visitors yet but with migration starting to pick up on the south coast I shouldn't have much longer to wait.

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