Monday, 30 March 2015

Nest box camera

This is the seventh year of my nest box camera and the prospective occupants for this year have just started bringing in nest material in the last two days.

The box was bought from HandyKam in 2009 and has been occupied every year since.  It is on a north-facing wall just outside the front door.  The camera takes colour still photos and videos if there is sufficient light and infrared black and white pictures if there is not.

In 2009 two blue tits built a nest in the box but one of them was killed by a sparrowhawk before any eggs were laid.  In 2010 a pair of great tits moved in and laid two eggs.  Both hatched but one chick died within 24 hours.  The other developed normally but never fledged and died in the box.  When I retrieved it I found that it was trapped by its leg in a strand of string the parents had woven into the nest.  Very sad and frustrating as, with a roof-mounted camera, I couldn't see what the problem was.

After that things improved.  In 2011 blue tits laid 11 eggs and all hatched.  All 11 chicks fledged on 31st May.  The same success in 2012, with 11 blue tit eggs, 11 hatched, and all 11 chicks fledged on 7th June.

In 2013 there was a very cold spring.  Blue tits moved in and laid only 2 eggs but both chicks fledged successfully, although much later than average on 19th June.

Last year there were 8 blue tit eggs and again all hatched and fledged.  It is amazing to watched them develop from this

to this

to this in the space of 19 days.

I was also able to photograph the parents bringing in spiders and caterpillars

and the chicks fledging on 1st June. 

If the present birds move in and build a nest I will make another page on the blog (accessed via a tab below the header photo at the top) so I can make regular updates.  I'll put a weekly update on this page as well.  Let's hope it is another successful year.  I had half expected tree sparrows in the box this year as there are so many of them around and they seem to be laying claim to most of the nest boxes.

Saturday, 28 March 2015

Bird of the week - Willow tit

Willow tits (Poecile montanus) are difficult to distinguish from marsh tits unless you hear them call or sing.  Their population is in decline and they are red listed, yet I see them on most visits to Prestwick Carr, Big Waters or Far Pasture.

These data from the BTO confirm the population decline over the past 40 years.

Data from the Bird Atlas confirm the willow tit's restricted range.  This is the winter distribution

and this is the breeding range.

Watch the BTO video on how to tell willow tit from marsh tit here.  Read more about willow tits from the BTO here or on BTO BirdTrends here or BTO BirdFacts here.  Listen to the BBC Tweet of the Day on willow tits here.

Wednesday, 25 March 2015

Hazel catkins

The common hazel (Corylus avellana) is one of many of our native trees that are wind pollinated.  It is monoecious, meaning that each plant carries male and female flowers, both known as catkins.  It flowers very early and the catkins are out now.  The male catkins, pale primrose yellow and up to 12cm long, are also known as lambs' tails.  I read that bees can collect the pollen but only with difficulty and in small amounts - because it is carried by the wind the pollen is not sticky.

The female catkins are tiny and mostly concealed within the buds that will form the hazelnuts. Only the red styles protrude.

This shows the male and female catkins together.  The female flowers have to be fertilised by pollen from other trees. 

Monday, 23 March 2015

Ruffled feathers, and worse

I first noticed this poor bird at the end of last year and took this photo on 2nd January.  As described in a previous post, it had abnormal body and tail feathers and discoloured wing feathers.  I sent pictures to the BTO but they didn't know what was wrong with it.

In a follow up post on 4th February the feathers looked worse but the bird was still behaving normally.

The last time I saw it was on 27th February, by which time it had lost its tail feathers altogether, plus a lot of body feathers.  I presume it died or was predated.

At the same time as the last photos above I noticed a similar but less severely affected bird in the garden but I didn't manage to photograph it until 8th March.  It still has fairly normal tail, head and wing feathers but deranged body feathers and a lot of missing feathers around its neck.  Like the other one it flies and feeds normally but it spends a lot of time preening, as if the feathers are irritating.  I have had a good look around on the internet and I wonder if these two birds might have a severe feather mite infestation.

This is the same second bird now.  It doesn't look significantly worse than two weeks ago and still behaves normally.

In recent days I have also seen this blue tit in the garden.  It has lost its tail, which happens, but its body feathers are abnormally fluffed up and it doesn't fly well.  It rarely gets on the peanut feeder but behaves like a dunnock, catching what the other birds drop from the feeder.  It also has an obvious bill deformity, so it not just a missing tail or just a feather problem.

And then there is this bird with a localised and rather different feather abnormality.  I don't know if all these problems are connected, or the cause of any of them.  If you know what they are please leave a comment.