Wednesday, October 12, 2016

Looking For Linnets

Linnets require seeds throughout the year, and they frequent areas where they can find lots of such food. Typical areas for Linnets include rotational set-aside, winter stubbles, root crops and break crops. Break crops are secondary crops grown to interrupt the repeated sowing of cereals as part of crop rotation. Oil-seed rape and associated broad-leaved weeds provide ideal food for Linnet chicks in the spring with Linnets one of the few species to feed their nestlings entirely on seed. Linnets need thick hedgerows and scrub for nesting but will also use bramble areas on grassland, marginal land and waste ground. 

Where can Linnets find all of these things on modern farmland? The answer is that it is becoming increasingly difficult for Linnets to find those things in order to maintain their population. The graph shows the decline in the population of Linnets between 1996 and 2014. Combined figures from the BTO Common Bird Census and BTO Breeding Bird Survey. This is a pretty disastrous fall in numbers for yet another farmland bird. 

England - Linnets 1996-2014 - BTO

With the above in mind I met up with Andy for another ringing session at a set-aside plot at Cockerham where we hoped we might catch and ring more Linnets and so collect more data for the BTO. The morning was fine, perhaps too fine with sun on the nets but at least very little wind. 

We caught steadily but slowly with a four hour session producing 18 Linnets and 1 Reed Bunting. This increased out Linnet catch to over fifty in just two visits with no recaptures. Once again juveniles/first autumn birds dominated with just 3 adults and 15 juvenile/first years. 

 Linnets - 12th October 2016

Male Linnets are marginally bigger than females as can be seen from the figures above. The wing length of the UK race of Linnet Linaria cannabina varies between 76-85mm (Birds of The Western Palearctic) which serves as a check on our sexing technique of studying the 7-9th primary feathers to separate male and female. We are finding that anything greater than 81mm confirms a male, whereas a measurement below 80mm confirms a female. 

Linnet

Studying the tail is a very reliable way to age Linnets at the moment. The tail feathers of a juvenile/first autumn have a mostly pointed shape, particularly the outermost unmoulted ones. By October an adult Linnet has completely moulted and replaced its tail feathers whereby the resultant shape is both more rounded and less worn than those of a juvenile/first year Linnet. This holds true for many finches and other species at this time of year where adults and juveniles have differing moult sequences. This is not entirely fool proof as a bird might lose all or some of its tail feathers at any time, and ringers must be mindful of that possibility. 

Adult Linnet

Juvenile/first autumn Linnet

Today’s Reed Bunting proved to be a first autumn female. 

Reed Bunting

Our ringing was carried out to a three hour overhead procession of Pink-footed Geese leaving Pilling Marsh for their daytime feeding areas. Several thousand flew south between 0700 and 1000, with many flocks of several hundred birds among the hordes that passed over. 

Pink-footed Geese

Otherwise – a few tree Sparrows and Skylarks plus the now regular Sparrowhawk. On the way back I stopped at Pilling Marsh to see 28 Little Egret and 2 Buzzard.

Linking today to Eileen's Saturday Blog.


12 comments:

Patrycja Piotrowska said...

Interesting post! In Poland, Pink - footed Goose and Little Egret are uncommon species.
(Ciekawy post! W Polsce gęś krótkodzioba i czapla nadobna są rzadkimi gatunkami.

Linda said...

Awesome series, Phil!

David Gascoigne said...

Great job, Phil. The numbers were not as sensational as your recent experience with the Goldcrests, but I am sure you were satisfied nonetheless. We will be banding again on Saturday morning, weather permitting, and on Friday evening I am meeting with another bander who has a permit to band owls, with a view to banding Saw-whet Owls. I have no idea what kind of success we will have but I have examined the topography and wood lot characteristics and I think we have a good chance to trap this species which is migrating at this time of the year.

Margaret Adamson said...

Lovely shots of the geese in fight

Prunella Pepperpot said...

Thank you for the poem link Phil. It did make me smile.
Your posts are very educational and I now find myself and my husband looking closer at birds to try and spot a more unusual ones!! Sadly I will never get as close as you.
Have a wonderful weekend :)

Sallie (FullTime-Life) said...

Do linnets frequent backyard bird feeders? (Since they are seed eaters). Come to think of it, what is your feeling about feeders?

Stuart Price said...

Always nice to see Linnets, I recall my first ever pair sitting on a fence in the Lake District. Must be over 40 years ago..............

Lowcarb team member said...

Interesting to read although slightly worrying, and sad too, that modern farmland is affecting bird numbers, and other natural life too.

I like the photo of the geese flying high.

Have a good weekend

All the best Jan

eileeninmd said...

Wonderful birds and photos Great post and info on the Linnet, Phil. Thank you for linking up and sharing you post! Happy Saturday, have a great weekend!

TexWisGirl said...

so much detail in those 'browns'. :)

Powell River Books said...

What an amazing decline. With the weather changes lately we are seeing different birds come to our area. - Margy

Jeanne said...

Very interesting post Phil. and sad to see that big of a decline. This linnet is such a lovely bird, and one that i have not seen in Texas.

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