Seeing Yellow…

Here at the farm in Denmark, I managed to catch a single yellowhammer (Emberiza citrinella) close to the hedgerow last week. Again I’m attempting to apply my tactic of taking multiple photos of the bird in hand and trying to “work it out” later, with the help of the many on-line resources available (including experienced ringers) which are invaluable!

Yellowhammer, Denmark. April 2015.

Yellowhammer, Denmark. April 2015.

At first I assumed it was a female, as there was limited yellow visible on the head and the shaft of the feathers was broadly coloured black. However after reading this detailed article (Dunn & Wright, 2009), I was reluctant to decide on a gender for this bird too quickly. (You may have noticed the bird had a small wound on the side of the head above the right eye. Apart from this it appeared in good health.)

Yellowhammer, Denmark. April 2015.

According to Jenni & Winkler (1994) the postjuvenile moult involves all lesser, median and greater coverts, putting them out of the question when searching for moult limits, however it is always worth a look! The next step is to search for a moult limit among the tertials, carpal covert, alula and tail feathers which may be partially moulted in some birds during the postjuvenile moult. Adults on the other hand, undergo a complete postbreeding moult, which means it SHOULD be possible to differentiate the two age groups at the moment. A limited prebreeding moult has also been reported in some birds, but this was restricted to the head and upperparts.

Yellowhammer, Denmark. April 2015.

Having a closer look at the tertials, the innermost tertial appears to have a darker center and a more clearly defined brown edge compared to the two larger tertials where the border appears more diffuse. According to Dunn & Wright (2009) tertials with a distinct boundary (as seen in the innermost tertial) are typical of first year birds. However the DigiGuide from Ottenby, suggests that this is typical of adult tertials, causing me some confusion. So it is possible a moult limit is present in the tertials, but I’m unsure which feather belongs to which generation. Furthermore looking at the secondaries, they appear notched, or heart shaped at the top, which Dunn & Wright suggested was also typical of first year birds, with adults having a more flat or square appearance. However, I’m still not confident that I am correctly interpreting these subtle differences, if they are even present.

Yellowhammer, Denmark. April 2015.

Comparing the photos of the primary coverts, alula and carpel coverts with those in the DigiGuide from Ottenby, I didn’t get very far. To be honest I’m not exactly sure what to look for.  The primary coverts don’t appear to be loosly textured, and they are quite glossy, possibly suggesting adult like. The pale yellowish-buff edge on the middle alula appears less green-ish that that of the smallest alula and the carpel covert – but is that just my eyes? or could this be a result of wear with the difference only evident towards the tip of the feather?

Yellowhammer, Denmark. April 2015.

From my reading of the literature, the tail and both upper- and under-tail coverts seems to be a good place to look for some reliable clues to ageing and sexing. In general the tips of the tail feathers appeared rounded or with blunt edges, and not pointed or sharply angled, which suggests in this case adult type feathers (Dunne & Wright, 2009). On closer inspection, it appears to me that one tail feather appears more sharply angled at the tip (see yellow arrow). It is also possible that a first year could either accidentally or deliberately moult all tail feathers (or most of them, see David Norman’s blog), resulting in an adult like tail. Hmmm…

Yellowhammer, Denmark. April 2015.

The extent of white on the 5th and 6th tail feathers was mentioned in the literature, but I don’t think this bird fits into any of the extremes where it can be used to assist with ageing. However the shaft colour of the upper tail coverts may give us a clue to sexing. In males the shaft of the upper tail coverts is a similar colour to the feather (chestnut brown) whereas in females the shaft is darker, almost black, as seen here.

My conclusion; female yellowhammer – age- to be continued!

Resources:

Some interesting seed eaters – David Norman Blog

Jenny C. Dunn & Chris Wright (2009) Ageing and sexing the Yellowhammer Emberiza citrinella caliginosa during the non‐breeding season, Ringing & Migration, 24:4, 240-252. Link

Jenni, L. & Winkler, R. (1994): Moult and Ageing of European Passerines. Academic Press, London, UK

Greenfinches – a closer look

Last week I received new rings and dug out my ringing equipment and nets here at the farm in Denmark. The last feathers I felt in my fingers were neo-tropical birds in the lowland jungles of Peru. It was both exciting and refreshing to reacquaint myself with some locals, despite the fact that the spring weather left my fingers more than a little cold and stiff – that didn’t happen in Peru!

Male greenfinch, Denmark. April 2015.

One of the first birds I caught was a male greenfinch (Carduelis chloris). I haven’t had much experience with greenfinches, having ringed a total of 4 to date, and I didn’t realise they could present some interesting challenges, especially in spring. Adult birds undergo a complete post-breeding moult in the late summer / early autumn, while first year birds have a partial post-juvenile moult slightly later than the adults, which can be limited or quite extensive, sometimes including primaries as I found out from David Norman’s detailed blog and Stephen Menzie’s blog. However in southern greenfinch populations the post-juvenile moult can also be complete (Harris, 1992).

Male greenfinch wing, Denmark. April 2015.

I decided to review my photos to better understand how to accurately age Greenfinches in spring, for when I (hopefully) come across them again. Firstly the plumage was in superb condition with bright contrasting colours and sharp clean edges on the feathers, with little or no sign of wear. The primaries and secondaries appeared dark, with a pale yellow edge. The tertials were broad, square and grey with dark centers (adult like). I was unable to find a moult limit within the greater coverts, or any contrast in wear between the adjacent carpal covert or alula (adult like) .

Male greenfinch wing, Denmark. April 2015.

Male greenfinch tail, Denmark. April 2015

The primary coverts were round in shape and had dark centres, with a yellowish green fringe, becoming greyish towards the tip of the feather (adult like). The tail feathers were broad, rounded and also in good condition (adult like). Having a closer look at the wing I spotted a feather which was a little different to the others. The innermost secondary (identified above with red arrow) contrasted with both the tertials and other secondaries as it was more brownish in colour, showing a reasonable amount of wear.

Male greenfinch wing with retained secondary, Denmark. April 2015

Combining all the information “presented” in the feathers, along with photos and information from various sources, it appears that this bird is an adult (3rd calendar year or older, EURING 6). However it has retained one secondary from the previous years plumage. According to Jenni & Winkler (1994) arrested moult, where a bird retains unmoulted feathers can “accidentally” happen in almost all species. It is more common among birds with that have limited time to moult i.e. long distance migrants, northern populations and late breeders.

Male greenfinch, Denmark. April 2015

As mentioned previously, research has shown that in southern populations (Harris 1992 in south Portugal) first year greenfinches (among other finches) can undergo a complete post-juvenile moult, thus making it difficult to differentiate age groups from late autumn onwards. However as this greenfinch was caught in Denmark, I think there is a very small possibility that it is a juvenile with a very extensive post-juvenile moult, retaining one single secondary. Furthermore I would expect a retained juvenile feather to have far more extensive wear, as the feather quality of juvenile feathers is much poorer than that of adults.

Female greenfinch, Spain. March 2014.

Female greenfinch, Spain. March 2014.

With southern greenfinches in mind I dug out some photos I took while ringing in Aiguamolls National Park in northern Spain in the spring of 2014. It is possible that the female greenfinch below is either an adult (EURING 6) having undergone a complete post-breeding moult, with no retained feathers, or a second year (EURING 5) with a similar complete moult, with no retained juvenile feathers. I’m somewhat glad I’m on the northern edges of the breeding range!

Female greenfinch, Spain. March 2014.

Female greenfinch, Spain. March 2014.

Now all I have to do is catch a few second years to put it all into practice!

First-year Greenfinches with moulted primaries – David Norman Blog

Finchy Fun – Stephen Menzie Blog

Harris, P. (1992) Ageing finches in southern Portugal, Ringing & Migration, 13:3, 175-176

Jenni, L. & Winkler, R. (1994): Moult and Ageing of European Passerines. Academic Press, London, UK

A taste of farm life

 

After four months travelling in South America we arrived back to Denmark in the middle of March. We are slowly adapting to the fresh spring weather (with a light sprinkling of snow yesterday), unpacking, sorting, washing and getting used to our new lives in Skive, where Rasmus’ parents live. We are very thankful to have a place to stay while we sort out the next steps in our lives. I am especially thankful we are living on a small farm, about 5km from the city, surrounded by nature and a host of farmyard animals, including a sheepdog (Max), 3 cats, 2 horses, 20+ chickens, 8 sheep and, at the last count, 8 lambs!

Our daily lives have changed drastically in the last few weeks; from sun cream, battling with Spanish and sightseeing to collecting eggs, feeding animals and playing fetch with a very eager sheepdog. We have, in many ways, gone from one holiday to another. Although I grew up in Ireland surrounded by pets (dogs, goldfish and hamsters), and I was very interested in horse riding for a few years in my early teens, I have never really spent much time with “farm” animals.

I have accidentally taken over the role as “fodermaster” (head animal feeder), which surprisingly takes up more time than I expected. My day is now filled with trips to the stables (and many changes of clothes) to provide food and water for a host of hungry animals. As it’s lambing season, the ewes are kept in the stable, both to protect the newly born lambs from the cold (spring takes its time to arrive here) and the possibility of predation from foxes or a passing wolf. Wolves have recently recolonised Denmark after 200 years absence!

All the other animals, except Magnus the ram, sleep under a roof. The horses, who spend there day out in the field retreat to the shelter of the stable overnight and the hens are tucked up in the hen shed by the time it gets dark. The cats are very happy cuddling up together on the straw bales while the dog get the luxury of sleeping in the house!

In the morning one of the first tasks is to fill the empty stomachs. The bleating sheep get very excited when they receive their corn mix and silage which keeps their jaws busy chewing during the day. Among the sheep there is one lamb, which at the start, didn’t thrive and grow like the others. We made the decision about a week ago to provide it with supplementary food, which it gets via a baby’s bottle. This task I have also taken on, one which gets me out of bed eagerly every morning! Little “Tiny” is growing stronger everyday!

Before being released back into the field the horses get a cereal snack and some silage to keep them happy. Releasing the hens is a slightly more tricky affair. They haven’t exactly learned where they are “supposed” to lay their eggs, despite many encouragements with a rubber fake egg (it does exist!). Each morning a single egg must be collected from behind the hatch, otherwise upon opening the hatch, the egg will roll outside and break.

That means that each morning I must make the somewhat treacherous journey through the hen house, between the two rows of clucking hens, complete with a puffed up cockerel, to collect that single egg. There isn’t much space in there and I must admit, it scares me a tad! Once that single troublesome eggs is collected the hatch can be opened and the chickens run to freedom (all be it limited!) where they happily peck holes in the compost from the day before.

I should probably mention that the animals are here as a hobby, not a business, and I can see the benefits of this! The animals provide you with endless hours of entertainment and company (especially the very springy lambs), ample opportunities for healthy outdoor physical exercise, a reliable composting service, food and wool!

I’m really enjoying farm life and hope I can incorporate some of it into my future life, where ever the road leads.