The Eurasian Wryneck (Jynx torquilla)

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Eurasian_Wryneck

Another fantastic bird that has featured on #BeakOfTheWeek – the Eurasian wryneck (Jynx torquilla)! It is one of only two species in the genus Jynx, along with the red-throated wryneck (J. ruficollis), both of which belong to the woodpecker family (Picidae). Like other woodpeckers, it has the characteristic large head and long tongue, but with a few slight differences. Most woodpeckers have a powerful bill, whereas the wrynecks have a shorter, more slender bill. This is suited to their feeding behaviour as they don’t use their bills to make holes in trees, but instead find and catch insects in crevices using their sticky tongue. They have an unusual threat display in which they twist their head in a snake-like manner while hissing. Consequently they have long been associated with ancient spells and witchcraft, and are responsible for the origin of the word “jinx” (cf. Jynx). The meaning of the species name torquilla also relates to this behaviour, as it comes from the Latin verb “torqueo”, meaning “to twist”.

Despite belonging to the woodpecker family, the species can seem more characteristic of the thrush family. It prefers foraging on the ground, and can be seen sitting on branches more often than clinging to tree trunks. This is most likely because it lacks the stiff tail feathers that most woodpeckers have which help brace themselves against upright trunks. Individuals are  around 16–17 cm long and weigh 30–50 g. Their plumage pattern and colouring is reminiscent of nightjars (Caprimulgidae). Both males and females are mottled brown, buff, and grey on their upper body, and barred dark brown and buff on their underside, giving them a slight ‘dirty’ appearance. This colouring acts as very effective camouflage, making them very difficult to spot. Their song is a series of 8–15 loud “kwia” notes in quick succession, sounding quite similar to the lesser spotted woodpecker (Dendrocopos minor) but slightly more nasal in sound. Their alarm calls can either be shrill hissing, or a series of loud ‘tak’ sounds in close succession, sounding almost like clucking.

Here’s an example of their song:


 

The Eurasian wryneck is not a particularly common sight in the UK, being seen mostly on the Eastern and Southern coasts during autumn migration time, and less commonly in spring. It is estimated that around 280 birds visit the UK when migrating. However, it is a very widespread visitor to much of Europe and Asia in breeding season during the summer months, and is present in both Asia and Africa outside of the breeding period. Their preferred habitat consists of open country with orchards, woodland, fields, scrubland, and pasture. They primarily feed on ants, finding nests in holes and crevices using their slender bills and long tongues. They also feed on beetles and their larvae, aphids, flies, and spiders.

tree hole

As Eurasian wrynecks cannot excavate their own tree hole, they often use the old nest sites of other woodpeckers, sometimes even removing the nest and brood of another individual. When meeting, a mating pair will exhibit head swinging and feather ruffling, which acts as a courtship display. The species is generally monogamous, staying faithful to one mate. However, occasional polygyny occurs, meaning some males mate and raise offspring with more than one female. A clutch of 7–12 eggs is laid in May–June, and sometimes a second clutch is laid in June. Incubation of the eggs lasts around 11–12 days, and is shared between the male and the female equally, as is the feeding of the young. The nestlings fledge at 20–22 days, and become fully independent 1–2 weeks later.

The species has “Red Status” in the UK due to severe declines between 1800 and 1995 without substantial recovery. However, on the IUCN Red List of Threatened Species, it is of “Least Concern“. This means that the species isn’t globally threatened. Let’s hope it stays that way!

 

References

BirdLife International. 2015. Species factsheet: Eurasian Wryneck Jynx torquilla. Accessed 18/10/2015.

RSPB. 2015. Wryneck. Accessed 18/10/2015.

Winkler, H., Christie, D.A. & Kirwan, G.M. 2015. Eurasian Wryneck (Jynx torquilla). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.) 2015. Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. Retrieved from http://www.hbw.com/node/56121 on 21/10/2015.

BirdLife International. 2012. Jynx torquilla. The IUCN Red List of Threatened Species. Accessed 18/10/2015.

Wink, M., Becker, D., Tolkmitt, D., Knigge, V., Sauer-Gürth, H. & Staudter, H. 2011. Mating system, paternity and sex allocation in Eurasian Wrynecks (Jynx torquilla). Journal of Ornithology. 152: 983–989.

Images (from top to bottom):

Eurasian wryneck (Jynx torquilla) taken by Robert Nash is licensed under CC BY-SA 3.0.

Eurasian wryneck (Jynx torquilla) taken by Åsa Berndtsson is licensed under CC BY 2.0.

Audio

Patrik Åberg, XC26770. Licensed under CC BY-NC-SA 3.0. Accessible at www.xeno-canto.org/26770.

 

European Researcher’s Night: Science Uncovered

facebooktwitterFor the past ten years, European Researcher’s Night has opened the doors of science institutions to the public. After just over a year of data collection and approaching half of all bird species scanned, this year’s Science Uncovered event at the Natural History Museum at Tring presented a great opportunity for us to showcase our research and get the public involved.

science uncovered stand

The final preparations- bird bill bunting and all!

Our stand was located in the museum’s amazing Victorian galleries, surrounded by Walter Rothschild’s zoological collection. Alongside talks from curators and researchers, we were joined by an array of stalls exhibiting content from taxidermy demonstrations and careers in biology to the history of Australian birds told through beautiful manuscripts, artwork and specimens.

SciUn1

The variety of bill form & function.

We decided to showcase our investigation of bird bill variation and evolution through the stages of our research- from museum specimen to 3D scan and from the landmarking of these scans to analysis. It was particularly important for us to highlight the immense value of the Natural History Museum’s ornithological collections to our work. Without this incredible resource, housed at Tring, our broad-ranging survey of bird bills would not be possible. We used a selection of bird skulls from the museum’s handling collection and data-less bird skins (used for trialling our photography and scanning methods) to display a sample of bill diversity and highlight the variety of functions they serve.

We also demonstrated how we are able to generate 3D images from these specimens using our scanners, as well as letting members of the public try their hand at this essential part of our data collection process. This allowed us to discuss some of the inherent difficulties we have had to overcome in 3D scanning something as diverse as bird bills- from the sheer variety in volume and shape to the difficulties caused by feathers and bristles. It was also ideal in showing how the highly detailed images created through this process reveal so much more than traditional bill measurements.

SciUn2

Our portable scanner in action.

With our crowdsourcing site Mark My Bird launched earlier the same week, perhaps most important was the chance to discuss how the public can now participate in this research. All the scans we generate need to undergo a process called landmarking- selecting a series of key points on each 3D scan. This needs repeating multiple times across all 10,000 species of bird we are aiming to image- a fascinating but extremely time consuming task! This is where the assistance of citizen science comes in: by signing up to our site, anyone can view these amazing scans up close using our simple 3D interface and actually landmark bills. This will provide data that will directly contribute to our analysis and help us answer key questions about avian evolutionary diversity. Once our findings have been published, these scans will remain available to everyone- whether for general interest or further research- via the Natural History Museum’s DataPortal.

We had lots of interested future landmarkers sign up on the night and it was a brilliant opportunity to talk about our research. Many thanks to the Natural History Museum for letting us get involved and for everyone who came to our stand with interesting questions and such thoughtful feedback.

If you didn’t make it along to the event but would like to learn more about our project (or jump straight in and have a go at bill landmarking) you can do so on our crowdsourcing website, Mark My Bird: https://www.markmybird.org/

If you would like to learn more about European Researchers’ Night and the Natural History Museum’s involvement, check out the following link: http://www.nhm.ac.uk/visit/exhibitions/science-uncovered-2015.html

Staying on target

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Hello, Mark My Bird lovers!

Once again, you’ve blown us away with your enthusiasm. It’s been less than two weeks since we launched, and last time I looked, you guys had collectively marked over 2,500 bills. A notable mention at this point has to go to Peregrin3, who since registering two days ago, has marked around 400 beaks. Amazing!

A few of you have asked for feedback on how well you’re doing. This is important for us too, because it helps us to identify mistakes that could affect our analyses later. Reassuringly, most of you are doing just fine. There are a few common mistakes that crop up, which we’ll take a look at below. We’re working on some updates to the landmarking tool that should flash up a warning if your landmarks start to stray too far from the brief.

How does this work then?

As we’ve already hinted to some of you who follow us on Twitter, there are some quality control measures built in to the site. One of them is that everyone who registers is given the same two training birds as the first bills they landmark: the shoebill stork (Balaeniceps rex), and the brown-chested alethe (Alethe poliocephala).

This shoebill is coming to haunt your dreams and steal your soul... © Su Neko, CC-BY-2.0

This shoebill is coming to haunt your dreams and steal your soul… © Su Neko, CC-BY-2.0

We chose the shoebill because a) it’s “easy to landmark” (big, sharp lines, sensible feathers), and b) just look at it. Look at it! It’s brilliant. We chose the alethe because, in terms of beak shape, it’s incredibly average, making it typical of most of the bills a user will see on Mark My Bird. The repeated efforts to mark these birds are our dataset for this blog. We’ll focus on the shoebill first.

I’m not going to dive in to the details of how we ran this analysis today. The method is called Geometric Morphometrics, and I’ll probably write another blog for you on that at a later date. In a nutshell, we’ll be using it to see how much variation in bill shape there is between different bird species. In this case though, everyone marked the same shape (the same shoebill… bill), so the variation will be caused by different people choosing to put their landmarks in slightly different places. For those of you who are in to morphometrics, all the analysis was done in the Geomorph R package.

Science!

Here’s what all the shoebill data you guys generated looks like:

shoepc12_rings

Each dot on this graph represents a different person, 165 in total. 85% fall inside the green circle, and have put the landmarks very close to where the members of Team Macrobird did. So well done! The person who came closest to our landmarks was hughbrazier (black dots), whose landmarks are shown compared to mine (grey dots).

shoe_hb

hughbrazier’s shoebill landmarks

What about the points that aren’t in the green circle? There are two more clusters in the graph, shown by the blue circles. These represent “loops”, where the user tried to add more points along the curves in between points they’d already placed. The point resampling along the curve gets really confused, and makes a right mess of things! One cluster is loops along the left and right curves, the other cluster is loops along the midline.

This is what happens when a loop gets put along one of the edge curves. It doesn't look much like a shoebill any more.

This is what happens when a loop gets put along one of the edge curves. It doesn’t look much like a shoebill any more, tbh.

We didn’t see this coming, but with hindsight, this is kind of our own fault. We should have been more specific in the instructions that the points along the curves have to be clicked from front to back in order. We’re working on an automatic check to try and stop people from making this mistake in the future.

I won’t name and shame the worst shoebill. Not only was there looping, but as this person looped, they also managed to mix up their left and right. Whoops!

We had slightly less data for the alethe, as 33 people had had enough, and stopped marking after they’d done the shoebill. It’s pretty much the same story, although this time, JohnF was closest to our landmarks.

JohnF's brown-chested alethe landmarks

JohnF’s brown-chested alethe landmarks

You can see that there is a small difference between where JohnF decided the keratin met the feathers and where I did. These small differences are the sort of thing we’d expect to see on a typical bill on Mark My Bird, and is why every bill has to be marked by multiple people: we need to get an idea of how much “noise” there is in the data.

In conclusion

We have some work to do to the back end of Mark My Bird, but the good news here is that most people are doing a great job. You carry on being fantastic. And if you want to see your own shoebill or alethe, post to the forum or send us a tweet with your Mark My Bird username, and we’ll try to get back to you ASAP.