Montezuma Oropendola (Psarocolius montezuma)

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This New World blackbird (Icteridae) has got to be one of my all-time favourite birds to scan. Usually a few times a week (after you have been working with museum collections for a while and every species is not as exciting as it once was) you will open a draw and marvel at nature’s achievements. From its bright yellow tail to its simply fantastic multi-tonal face and beak, this bird is stunning. The joy at this species didn’t stop there, as not only did it look good but it scanned beautifully. It was done and dusted in 5 minutes flat. As someone who spends a large portion of their time 3D scanning birds this is quite the treat.

Montezuma Oropendola in flight.

Montezuma Oropendola in flight.

You can see how beautifully the scan of the Montezuma Oropendola or Great Oropendola came out by checking out our #BeakoftheWeek tweet.

 

  • What does it look like?

    Say you are out for a stroll in Mexico and you see a beautiful avian specimen sitting in a nearby tree, how would you know if it is one of these guys? Being with a local bird guide would help, but apparently they are not always on hand. Knowing what they look like is always a good start, and by taking a scrutinising look at the picture below you’ll hopefully get your eye in for such an occasion.

    Males are slightly bigger and heavier than females (m-47.5cm,  ~500g; f-40cm, ~250g), and they do look similar so remembering this fact will be helpful in identifying the sex of what you are looking at. Starting from the bottom up, they have black legs, a yellow tail with black central feathers (retrices), dark chestnut body feathers and black head and neck feathers. Their faces have a patch of bare blue skin with a pink wattle under it and then the beak is half orange (from the tip to the centre) and half black (from the centre to where it meets the facial feathers).

    Montezuma Oropendola in all its glory.

    Montezuma Oropendola in all its glory.

    As we like to say, you cannot guarantee that you will get to see any bird species that you set out to see, so knowing what it sounds like is a huge help when IDing bird species. Below is a sample of what they sound like, and you can head over to the fantastic Xeno Canto to listen to some more of their calls (it is Definitely worth having a listen to these as they are marvellous). Xeno Canto is a great way to spend a few minutes listening to random bird species if you find yourself at a loss.

  • Where can you find this bird?

    This central american bird is found from the Atlantic slope of Eastern Mexico and South through Guatemala, Belize, Honduras, Nicaragua, Costa Rica down to Panama. The map below shows in more detail the range of this species.

    This Oropendola is found in tropical forests and in forests along the banks of rivers (riparian forests) up to 1600m.

    Montezuma Oropendola range.

    Montezuma Oropendola range.

  • What does this species eat?

    This species tends to forage in the upper canopy, rarely on the ground and it eats a wide variety of stuff. This ranges from the fruits of the gumbo-limbo and the Florida thatch palm, as well as the more familiar bananas and cacao, to nectar, insects and small invertebrates. They have also been known to eat bird species such as Lance-tailed Manakin (Chiroxiphia lanceolata) chicks.

    Breeding

    Breeding occurs at different times across the range, but primarily from February to August. Their mating system is harem polygyny, where one male lives and mates with numerous females, but females only mate with one male. They live in colonies with a varying number of nests per colony, this can range from as low as 3 nests to as high as 172 nests, with the average being around 30-60, depending on where they are found.

    There is a dominance hierarchy amongst males which influences the amount of time males spend in a colony. The more dominant male spends the most time in the colony, with lower ranking males visiting when he is absent. In DNA tests of 21 chicks, dominant or alpha males were found to sire 33% of chicks and beta-males 19% with lower-ranking and males displaying outside the colony siring the rest.

    When displaying/showing off to females, males perform what could be deemed as a bow and is definitely worth checking out.

    Females are responsible for nest building, usually 13-22m from the ground, with it taking 13-18 days to complete a nest. The nest is a “purse” 60-180cm long, that is open at the top, and formed from coarse plant fibres of eg banana/palm leaves. The female lines the nest with dry leaves, which she often cheekily steals from neighbouring nests.

    You can see what the nest colonies look like in the picture below.

    Two eggs are laid which, incubated by the female, take 17-18 days to hatch before the chicks then remain in the nest for around 35 days, being fed by the female. In Costa Rica it is reported that usually only one chick survives.

    Montezuma Oropendola nest colony.

    Montezuma Oropendola nest colony.

  • Good news on this front, with this species being listed as “Of Least Concern” on the IUCN redlist. It has range of around 450,000km2 and is seen as quite common in a lot of places across this range, which would be the reason for this lower degree of concern for this species. This is good news for colourful beak fans!

  • For further reading this week I have selected a paper that looks into the effect of sexual selection on song evolution in oropendolas and caciques.

    For further interest, and i’ve gone off-piste here, I find the thought of using DNA to encode data fascinating and thought some of you might as well. If you do, head on over the Nature News to read some more.

    Oropendola intrigued by song evolution?

    Oropendola intrigued by song evolution?

References

. 2010. Montezuma Oropendola (Psarocolius montezuma), Neotropical Birds Online (T. S. Schulenberg, Editor). Ithaca: Cornell Lab of Ornithology; retrieved from Neotropical Birds Online: http://neotropical.birds.cornell.edu/portal/species/overview?p_p_spp=680076

BirdLife International (2016) Species factsheet:Psarocolius montezuma. Downloaded from http://www.birdlife.org on 31/08/2016.

BirdLife International. 2012. Psarocolius montezuma. The IUCN Red List of Threatened Species 2012: e.T22724004A39873355. http://dx.doi.org/10.2305/IUCN.UK.2012-1.RLTS.T22724004A39873355.en. Downloaded on 26 August 2016.

Fraga, R. (2016). Montezuma Oropendola (Psarocolius montezuma). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from http://www.hbw.com/node/62242 on 26 August 2016).

Images and Videos

BirdLife International and NatureServe (2014) Bird Species Distribution Maps of the World. 2012. Psarocolius montezuma. The IUCN Red List of Threatened Species. Version 2016-1.

Montezuma Oropendola in all its glory is by Doug Janson and is licenesd under CC BY-SA 3.0.

Montezuma Oropendola in flight is by Paulo Philippidis and is licensed under CC BY 2.0.

Montezuma Oropendola nest colony is by Charlesjsharp and is licensed under CC BY-SA 3.0.

Oropendola intrigued by song evolution? is by Jerry Oldenettel and is licensed under CC BY-SA 2.0.

Audio

Peter Boesman, XC274124. Accessible at www.xeno-canto.org/274124.

 

The Sickle-billed Vanga (Falculea palliata)

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From the fantastically diverse vanga family (vangidae) the sickle-billed vanga really is sight to behold.  When a species has a bill as distinctive as this you can see why it would be quick to identify on #BeakoftheWeek, and low and behold the bird that the bill belonged to was quickly ascertained in the weekly challenge. Some of the beaks we have had the opportunity to scan at the Natural History Museum collections in Tring are a joy to work with, and this was definitely one of those.

Here is a nice video from the internet bird collection for you to watch to get a feel for what this bird looks like and how it moves.

 

  • What does it look like?

    The sickle-billed vanga is the largest in its family and it really stands out because of the strongly decurved bill that is possesses. There is no sexual dimorphism in this species, with both males and females being mostly white except for its upperparts, which are black with a blue sheen (as can be seen below). These vangas have blackish-brown irises, its legs are dark grey/pale blue and its bill is bluish grey fading to ivory at the tip.  Juveniles are similar in appearance to adults.

    sickle-billed vanga 2

    Sickle-billed vanga

    This is all very well and good if you can see the bird, but what if it is doing what birds are wont to do and hiding just out of sight? Well then we can rely on what it sounds like, if it decides to make any sound that is. Below is a recording of this species in the wild for you to memorise if you happen to be heading out to Madagascar.

  • Where can you find this bird?

    This species is endemic to Madagascar and is a year round resident along the whole of the western side of the island nation, as can be seen below. They are typically found in dry deciduous forests and Savannah.

    Sickle-billed Vanga range

    Sickle-billed Vanga range

  • Diet

    This species forages in holes and crevices of living and dead trees on the hunt for invertebrates (such as spiders, beetles and cockroaches) and small vertebrates (e.g. geckos). In the non-breeding season they form large foraging groups of between 20-30 individuals and sometimes form mixed groups with other species such as Madagascar Crested Drongos (Dicrurus forficatus).

    Sickle-billed Vanga

    Sickle-billed Vanga

    Breeding

    These vangas breed between October and January in NW Madagascar. Interestingly they are Polyandrous, where more than one male mates with one female and all the males (plus the female) then feed the young. These modern males also help with predator defence, territorial defence and sometimes incubation and brooding.

    This nest itself is built 9-16m off the ground in the fork of a tree and is formed from twigs into a cup-shape before being lined with more comfortable materials. Once it is ready a clutch of 3-4 eggs will be laid, which will then be incubated for 16-18 days. The chicks will then remain in the nest for 19-23 days before entering into the real world.

  • Good news on this front in that this species is seen as of “At Least Concern” on the IUCN Redlist for species. It is common to fairly common across it’s large range and it also found in many protected areas.

  • Sickle-billed vangas are polyandrous, as mentioned previously, which is a rare mating system thought to only occur in less than one percent of bird species. It is well documented in phalaropes, although this “strange” mating system did lead to John James Audubon mislabelling all of his males and female phalaropes in his illustrations.

    There are two types of polyandry: Sequential polyandry is where a female mates with a male, lays eggs and then leaves the male to do the rest as she goes off to find another male to mate with, and Simultaneous polyandry, where a female holds a large territory which contains numerous smaller nesting territories where males care for the eggs and young.

    For further reading this week I am providing a link that will explain polyandry in more detail and also provides links to information on different mating systems, such as polygyny and cooperative breeding. Follow this link to a Stanford University site to begin your learning journey.

References

BirdLife International (2016) Species factsheet: Falculea palliata. Downloaded from http://www.birdlife.org on 26/08/2016.

BirdLife International. 2012. Falculea palliata. The IUCN Red List of Threatened Species 2012: e.T22708041A39344831. http://dx.doi.org/10.2305/IUCN.UK.2012-1.RLTS.T22708041A39344831.en. Downloaded on 25 August 2016.

Yamagishi, S. & Nakamura, M. (2016). Sickle-billed Vanga (Falculea palliata). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from http://www.hbw.com/node/60562 on 25 August 2016).

Images and Videos

BirdLife International and NatureServe (2014) Bird Species Distribution Maps of the World. 2012. Falculea palliata. The IUCN Red List of Threatened Species. Version 2016-1

ian_hempstead, IBC1195731. Accessible at hbw.com/ibc/1195731.

Keulemans’ Sickle-billed vanga by John Gerrard Keulemans is licensed Public Domain Mark 1.0.

Sickle-billed vanga by Cédric de Foucault is licensed under CC BY-NC-SA 4.0.

Audio

Hans Matheve, XC155300. Accessible at www.xeno-canto.org/155300.

The Secretarybird (Sagittarius serpentarius)

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I say this far too frequently for it to warrant much merit but this is definitely a #favebird. Not only is it a highly skilled snake assassin but it has some rather fanciful “hair” to boot.

This one was solved pretty quickly on #BeakoftheWeek by our resident expert but it was mistaken for quite a few other accipitriformes first.

Check out the video below for a quick run through about this species before diving into a bit more detail.

  • What does it look like?

    This rather large bird is over a metre tall (125-150cm), that is almost as tall as Kylie Minogue! I would love to say I have seen one of these birds in the wild, but I Should Be So Lucky. I will have to make do with wonderful pictures like the one below for the time being.

    This species weighs between 2 and 4.5kg and has a large wingspan of up to 215cm (as wide as Shaquille O’Neal is tall- wow).  It is an unmistakable bird with it’s long pink legs, bare orange face and black crest feathers. Males are similar to females, although females are slightly less blue in appearance and juveniles have a shorter tail and crest.

    Moving swiftly away from celebrity heights…

    Secretarybird

    Secretarybird

    Xeno canto has let us down on this occasion so the best I can do is relate a description of their calls from the fantastic Handbook of the Birds of the World. Their most frequent call, which they make whilst perched/in flight is described as a high-pitched “ko-ko-ko-ko-ka”. They can also be heard making a more audible “kowaaaaa” and a “cockerel-like broken “kurrk-urr””.  I don’t know about you but I feel like I could do quite a good impression of a secretary bird now, thanks again HBW.

  • Where can you find this bird?

    Endemic to Africa the secretarybird is typically found in open grassland and savannah in the sub-Sahara and tends to nest and roost in Acacia trees. As you can see from the range map below they are found extensively across Africa.

    Secretary Bird Range

    Secretary Bird Range

  • Breeding

    This species isn’t fussy, as long as there is a good level of food availability they will nest at any time of the year. Secretarybirds hold territories of 25-45km² in which they build their nests. Nests are formed 3-7.5m from the ground (although they have been seen much higher at 36m) on top of low trees such as an Acacia. The base of the nests is formed with sticks which are then lined with grass, wool and dung. They sometimes re-use nests but more often than not a new one is built.

    One-three eggs are laid, which are then incubated by both sexes (42-46 days). The chicks remain in the nest for typically 75-90 days, and can remain dependent for 62-105 days.

    Nesting Secretarybirds

    Nesting Secretarybirds

    Diet

    You would be mistaken to think the secretarybird restricts its diet to our serpentine friends, it mostly feeds on arthropods. Particular faves are beetles and grasshoppers, but it isn’t a finicky eater. They have been known to eat a wide range of small animals, ranging from lizards and frogs to tortoises, squirrels, hedgehogs, hares and birds eggs and young.

    In order to kill its prey is usually kicks them to death with its long legs and strong toes, before swallowing smaller prey whole and tearing larger prey apart whilst holding it down.

    This species is known to hunt around grass fires, eating prey as it tries to escape/if it has been killed by the inferno. What a way to go.

    Secretary bird feeding

    Secretarybird with a tasty treat

  • Unfortunately this species is listed as “Vulnerable” on the IUCN Redlist, with some surveys estimating that total numbers are only in five figures. Rapid declines have been seen across much of its range, with no sightings occurring in Western African making it perhaps the most threatened raptor in the region.

    There are number of factors which could be causing the decline in this species, such as cultivation, urbanisation, burning of grasslands reducing prey numbers and severe drought. It is hoped that by educating locals on the threats facing this species it will help to lessen this decline.

  • I have gone for a mix of further reading today, a bit of science mixed in with a bit of art.

    Let’s start with art. The illustration below is by Louis Agassiz Fuertes (b1874, d1927), a man synonymous with ornithological art. He produced thousands of drawings and paintings in various mediums throughout his lifetime before tragically dying in a car accident.

    Fuertes made his artwork from animals in their natural setting, as well as from fresh study specimens and in order to create these masterpieces Fuertes went on many expeditions, travelling thoughout much of the Americas and Africa.

    Not many people have a species named after them. Fuertes managed that achievement twice – Fuertes’s Oriole and Fuertes’ Parrot.

    By design this further reading is intended to whet the appetite and encourage you to go off and learn more.  I recommend doing a simple search to see more of his illustrations to start with (here is his fantastic white-cheeked hornbill).  John James Audubon, whom we have spoken about previously (click link and scroll down to further reading) was perhaps the most famous ornithological artist and Frank Chapman, curator of the American Natural History Museum who collaborated with Fuertes many times, wrote a comparison of Audubon’s and Fuertes’s work and personalities that can be read here. Frank Chapman also wrote an obituary of Fuertes in Auk where you can see in what high esteem he was held and read more about his achievements.

    Fuertes secretarybird

    Fuertes’ Secretarybird

    Now for a quick bit of science! Imagine the importance of accuracy when targeting a venomous snake, the consequences of missing could be deadly. This journal article (S.Portugal et al. 2016) looks into the locomotion and mechanisms behind the secretarybird’s kick and gives you a great insight into just how powerful this bird’s kick really is.

References

BirdLife International. 2013. Sagittarius serpentarius. The IUCN Red List of Threatened Species 2013: e.T22696221A49946506. http://dx.doi.org/10.2305/IUCN.UK.2013-2.RLTS.T22696221A49946506.en. Downloaded on 23 August 2016.

Kemp, A.C., Kirwan, G.M., Christie, D.A. & Marks, J.S. (2016). Secretarybird (Sagittarius serpentarius). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.).Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved fromhttp://www.hbw.com/node/53186 on 23 August 2016).

Images and Videos

BirdLife International and NatureServe (2014) Bird Species Distribution Maps of the World. 2013. Sagittarius serpentarius. The IUCN Red List of Threatened Species. Version 2016-1.

Fuertes’ Secretarybird by Louis Agassiz Fuertes is licensed under Public Domain Mark 1.0.

Nesting Secretarybirds by Peter Dowley is licensed under CC BY 2.0.

Secretarybird by Ian White is licensed under CC BY-NC-SA 2.0.

Secretarybird with a tasty treat by Jean & Nathalie is licensed under CC BY 2.0.

Planet Doc Full Documentaries. 2015. Secretary Birds of Africa | Nature. [Online]. [23/08/2016]. Available from: https://www.youtube.com/watch?v=t1UEneEPZO8.

 

The Apostlebird (Struthidea cinerea)

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I couldn’t wait to write a blog about this species, so I have waded straight into it before the dust has even settled from another round of #BeakoftheWeek.

I had the pleasure of working at a research station (Fowlers Gap) in New South Wales a few years ago where there was a group of habituated apostlebirds, which was a fantastic experience. All you had to do was give a whistle and they would fly over and gather around you in the search of tasty treats. This allowed me to get some great photos like the one below.

Apostlebird1

Apostlebird PC Elliot Capp @ornithzoologist

This social, cooperatively breeding passerine species is an Australian mudnester (Corcoracidae) and is one of many species that had the pleasure of first being described by British Ornithologist John Gould (in 1837). Yup, that is the man who pointed out to Charles Darwin that there was something special about those birds he had brought back from the Galapagos. The 12 seminal ground finch species. This subject could cause me to massively go off on a tangent as I am sometimes wanton to do, but I will stick to the apostlebirds this time.

Apostlebirds are the only member of their genus and one of only two species in the Corcoracidae family, along with the white-winged chough (Corcorax melanorhamphos). If you head over to Onezoom you can see what other species they are closely related to.

  • Apostlebirds are around 30cm in length and largely grey in colour (hence Cinerea, which means grey in latin) except for their brown wings and long black tail which has a greeny gloss in certain light. Sexes are similar in appearance, as are juveniles except that they appear to have slightly softer feathers on the head and body.  They have a black bill and legs.

    Investigative Apostlebird

    Investigative Apostlebird

    Apostlebirds are very vocal, with harsh, gritty calls. Xeno Canto, provider of an unparalleled range of bird calls and songs has once again allowed me to share with you the distinctive sounds these birds make.

  • Where can you find this species?

    Apostlebirds are endemic to Australia, across most of inland Eastern Australia with an isolated population in the Northern Territory. They prefer open habitats, and are typically found in arid and semi-arid woodlands/shrublands.  They can become quite bold and tame around places like campsites and farms, so you might be able to get a better view of them there, if you happen to be in Australia that is…

     

    Apostlebird Range

    Apostlebird Range

  • Breeding

    As I mentioned earlier on in this article, this species breeds cooperatively. This means that the breeding effort in this species is shared amongst members of the group, helping to take some of the burden off of the breeding pair. Members of the group help by assisting with tasks like nest building, egg incubation and nest defence.  The number of helpers in a group can be as high as 17.

    It is in fact the group-living nature of these birds that gave rise to their name.  They are often seen in groups of 12, much like Jesus’s Apostles. Although this species has a whole host of other names, such as the “Cwa-bird” and the “lazy-jack”. Apostlebirds also charmingly called “grey jumpers”, a name derived from their habit of jumping from branch to branch.

    As an aside, this species forms a fission-fusion society with these “breeding units” coming together with other breeding groups in winter to former larger groups, before then breaking off again when breeding season comes around.

    You scratch my back, i'll scratch yours.

    You scratch my back, i’ll scratch yours. PC Elliot Capp @ornithzoologist

    Breeding generally occurs between August and February, with exceptions occurring at other times of the year in drier areas where breeding can commence following rain.

    The mud nest, which all group members take part in building, is typically around 7m (range = 3-12m) from the ground in the horizontal branch of a tree. Nests are commonly built in Eucalyptus , Cassuarina and Acacia trees, and are constructed using dried mud, twigs and grass.

    Typically 3-5 eggs are laid, with the breeding female undertaking most of the incubating (19-20 days), although all group members help somewhat. The whole group then takes responsibility for meeting the nutritional requirements of the nestlings (18-20 days) and subsequently the fledglings for up to 10 weeks. Offspring form a major part of breeding groups and often stay in their natal groups for many years.

    Diet

    You’ll see these birds foraging on the ground looking for seeds and insects, although they have been known to steal eggs from other species’ nests and eat small mammals. They have been seen to kill mice by thumping them into the ground before eating them, what a delightful way to go.

  • How is this species faring?

    This species is not considered to be under threat according to the IUCN redlist but is seeing population declines in some areas due to drought, fire and clearance for agriculture leading to habitat loss.

  • The Biodiversity Heritage Library

    I don’t think we have given a shout out to the Biodiversity Heritage Library as of yet, so this is as good an opportunity as any.  It is a fantastic resource that has digitised a large amount of biodiversity literature, such as the Birds of Australia.  It has been created by a consortium of natural history and botanical libraries, such as the Natural History Museum (London) and Smithsonian Libraries, with the aim of digitising biodiversity literature in their collections and making them available to all (open access).

    This project gives members of the public access to reading material that they would most likely never get the chance to see otherwise, unless they had a wealth of time on their hands and the ability to travel the world on some carefree reading adventure.

    Here is the Birds of Australia for you perusal.

References

BirdLife International. 2012. Struthidea cinerea. The IUCN Red List of Threatened Species 2012: e.T22705385A38386489. http://dx.doi.org/10.2305/IUCN.UK.2012-1.RLTS.T22705385A38386489.en. Downloaded on 29 July 2016.

Rowley, I. & Russell, E. (2016). Apostlebird (Struthidea cinerea). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from http://www.hbw.com/node/60602 on 28 July 2016).

Photos and Videos

BirdLife International and NatureServe (2014) Bird Species Distribution Maps of the World. 2012. Struthidea cinerea. The IUCN Red List of Threatened Species. Version 2016-1 – range

Investigative Apostlebird by Benjamint444 is licensed under CC BY-SA 3.0.

Audio

Marc Anderson, XC171837. Accessible at www.xeno-canto.org/171837.

The Tawny Frogmouth (Podargus strigoides)

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The Tawny Frogmouth (
Podargus strigoides), a #BeakoftheWeek contender from last year,  is a weird and wonderful member of the Podargidae family.

Adult tawny frogmouth, perching in daylight, Queensland

Adult tawny frogmouth, perching in daylight, Queensland

Alongside oilbirds, potoos and some nightjars, frogmouths are part of the wider order of birds known as Caprimulgiformes. Literally meaning ‘goat-milker’ in Latin, this peculiar name is said to have derived from folk tales regarding the feeding habits of the European nightjar, thought to surreptitiously suck the milk from goats in the depths of night!

The Tawny Frogmouth was first described in 1801 by the great English naturalist John Latham who was able to study and name many species of Australian birds from specimens finding their way into England’s growing natural history collections at the turn of the 19th century. In his first great ornithological work ‘A General Synopsis of Birds’ he actually focuses on the unusual bills of these then so-called ‘goatsuckers’ as follows: 
“The bill in this genus is very short, and hooked at the end. Gape vastly wide: on the edges of the upper mandible seven or more stiff bristles.”

Tawny Frogmouth 2

Ornithological painting from the Natural History Musuem’s collection of First Fleet artwork: “Strigoid Goatsucker”, native name “Birreagal”

One of the earliest known images of these birds is part of the collection of artworks created during the First Fleet expedition of the 1780s that saw the formation of the first European colony in Australia. Over half the natural history artworks focus on birds, with a number acting as iconotypes (where an image has survived but the specimen it was taken from (usually the earliest known to science) has not).

This fantastic painting, noted as a type and labelled around its time of creation as depicting a ‘Strigoid Goatsucker, native name Birreagal’ was re-examined in 1970 and confirmed as being detailed enough to accurately identify as Podargus strigoides.

Tawny frogmouths can be found throughout Australia and Tasmania and are known to live in most available habitats- from forests and woodland to heaths and urban areas. Known for their ‘cryptic plumage’, their colouration is variable, but usually consists of greyish upperparts, streaked with barring and vermiculation in blacks and brown with females usually having darker feathers.

Frogmouths have often been confused with owls, seemingly as a result of their nocturnal habits, brilliant camouflage and expressive faces alongside some quirks of historic synonymy. Confusingly, some of the most commonly used names for the Tawny Frogmouth are ‘Birreagal’ and ‘mopoke’, a name also shared by the boobook, a small Australasian owl. The Latin name strigoides itself reiterates this, with strix meaning owl, and oides meaning form. Many resources continue to refer to frogmouths as ‘false owls’ or simply ‘tawny frogmouth owls’ for good measure; there are however a number of key differences between these taxa.

Unlike most owls with their strong legs and curved, pointed bills for killing prey, the tawny frogmouth has an extraordinarily wide, chunky bill ideal for catching and consuming insects. So too, during daylight hours frogmouths tend to perch on branches, utilising their extraordinary camouflage to blend in with their surroundings and avoid detection. Unlike owls, they gather most of their food by ‘pouncing’ from low branches to the ground where they mainly feed on worms, slugs, snails, reptiles, frogs and small mammals.

Tawny Frogmouth family- these birds have some of the most fantastical looking chicks.

Tawny Frogmouth family, New South Wales. Frogmouths have some of the most fantastical looking chicks.

Tawny Frogmouths breed between August and December with both sexes sharing incubation duties. Their nests are fairly loosely formed structures, primarily comprised of sticks and usually creating a platform between forked tree branches to safely raise their young  (having an average clutch size of 2 to 3 eggs) from the ground. These birds have distinctive ‘soft and low’ pitched calls, most commonly sounding like sequential bursts of ‘oom-oom-oom’ sounds, and are known to loudly bill-snap when threatened:


You can find out more about which species are related to the Tawny Frogmouth at OneZoom. For now though, I’ll end this post with a passage from another historical text, The Birds of Australia of 1911, which brilliantly captures the appearance and character of these birds:

‘The Frogmouths are beautifully soft-plumaged birds, with a motley of grey, brown, black and white markings. In the coloration then they resemble the dead bark of the bough on which they sit. To render it still more difficult of detection, the bird does not sit across the bough, but along it, assuming the stiff attitude of a rugged branch broken off short. The eyes are large and adapted to the diminished light of night, the brighter light of day seemingly making them dazed and inert. In both these characters they resemble the Owls. Their disposition is however, much milder, and they can be handled by day without attempting to offer any resistance. They are invaluable insect feeders, and capture their food, Cicadas, Phasmids and Beetles, &c., on the branches of the trees. After swallowing an insect they bring their mandible together with a loud snap, as if in satisfaction over the tit-bit.’

References
Handbook of the Birds of the World Alive, Podargus strigoides: http://www.hbw.com/species/tawny-frogmouth-podargus-strigoides (accessed April 2016)

White, John, A General Synopsis of Birds: Vol 2, Part 2, London, Printed for Leigh, Sotheby, & Son (1801). Available via Biodiversity Heritage Library:  http://www.biodiversitylibrary.org/item/105238#page/7/mode/1up

The First Fleet Expedition and Collections, Natural History Museum London- Library and Archives Collections: http://www.nhm.ac.uk/nature-online/art-nature-imaging/collections/first-fleet/art-collection/index.dsml (accessed April 2016)

Australian Museum, Podargus strigoides factsheet: http://australianmuseum.net.au/tawny-frogmouth (accessed March 2016)

Lucas, Arthur Henry Shakspere & Le Souëf, W. H. Dudley, The Birds of Australia,  London, Whitcombe and Tombs Limited (1911). Available via Biodiversity Heritage Library:
http://www.biodiversitylibrary.org/item/114952#page/9/mode/1up

Images and Audio

Adult tawny frogmouth, Queensland by Tatters is licensed under CC BY 2.0

“Strigoid Goatsucker”, native name “Birreagal” from the Natural History Museum’s collection of First Fleet artworks, available online: http://www.nhm.ac.uk/nature-online/art-nature-imaging/collections/first-fleet/art-collection/nathist.dsml?sa=1&lastDisp=gall&notes=true&beginIndex=264&desc=true

Tawny Frogmouth family, New South Wales by tinykettle is licensed under CC BY-NC 3.0

Audio recording of Tawny Frogmouth (Podargus strigoides) call, XC150467, by Marc Anderson. Accessible at: http://www.xeno-canto.org/150467

 

The Grey-necked Picathartes (Picathartes oreas)

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One of our #BeakoftheWeek nominees was the delightful grey-necked picathartes.

Grey-necked Picathartes (Picathartes oreas)

Grey-necked Picathartes (Picathartes oreas)

This rather bizarre-looking passerine is known by a number of other names: the red-headed picathartes, the grey-necked rockfowl and red-headed rockfowl. It is placed in the family Picathartidae along with the white-necked picathartes (Picathartes gymnocephalus).

The grey-necked picathartes lives in the rainforests of equatorial Africa, and tends to feed on invertebrates. It also sometimes feeds on plant matter, such as fruit and flower buds and vertebrates which it plucks from the forest floor and low lying vegetation. It’s IUCN Red List status is vulnerable as despite having a large range, it’s population is thought to be fragmented and declining.

Sadly there are currently no recordings available on xeno-canto, perhaps partly owing to the mostly silent nature of the grey-necked picathartes. It has been reported to sometimes makes a quiet hissing noise that lasts for a couple of seconds. Additionally, on approaching the nest it makes a single or double ‘peep’ call and then a low, repeated ‘ga-a-a’ sound.

This bird breeds during the wet season and can nest twice annually in areas where rainfall is high at two different times of the year. Both males and females contribute to building a cup-shaped nest made from mud, roots and fibrous vegetation, that is placed on cliffs, rocks and caves.

 

References

BirdLife International. 2015.  Picathartes oreas. The IUCN Red List of Threatened Species 2015: e.T22708119A85077576. . Downloaded on 05 April 2016.

BirdLife International (2016) Species factsheet: Picathartes oreas. Downloaded from http://www.birdlife.org on 05/04/2016.

Thompson, H. (2007). Grey-necked Picathartes (Picathartes oreas). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.) (2014). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from http://www.hbw.com/node/59384 on 7 July 2015).

Images

Grey-necked Picathartes (Picathartes oreas) taken by Stijn Cooleman is licensed under CC BY-NC-SA 3.0

The King Eider (Somateria spectabilis)

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This #BeakoftheWeek challenge allowed us to take a closer look at the king of the seaducks, the King Eider.

This is definitely in my top 5 favourite ducks, not least because it looks like Picasso got creative with its face in the design stage, and it is right up there on my “to see list”.

King Eiders taking flight

King Eiders taking flight

I have gone for a different approach with this blog entry, so that you can click on what you want to read about rather than having to scroll through to find what you are looking for. Hopefully it works a bit better!

The King Eider is from the anatidae family and is one of three members of the genus Somateria, which also includes the spectacled eider and common eider. The common eider is the duck that gives us eiderdown.   When the common eider nests it sheds feathers which are then collected and used to make some extremely comfortable pillows and duvets. If you fancy splashing out, a pillow alone can set you back around $3,000. I know, a bargain. Fortunately goose down pillows are available for far more reasonable prices.

You can check out what other species are closely related to the king eider on OneZoom.

  • As you can see from the range map below they are found exclusively in the Northern-hemisphere, breeding (Brown) around the Arctic coasts of Europe, Asia and North America and moving further south in the winter (Orange).

    King Eider Range

    King Eider Range

    This is a marine species, breeding on the edge of freshwater lakes, bogs, pools and small rivers, usually near to the coast. During the rest of the year it spends its time at sea, often in deep waters away from land (which can make accurately counting it rather tricky).

  • This sexually dimorphic large duck ranges in size from 47-63cm, with males being slightly bigger than females.  Males are unmistakable and the clear differences between the sexes can be seen in the video below.

    Males have a white breast and black rear half, crown and nape are pale blue, cheeks greenish and throat white. Their bill is orangey-red with a striking yellowy orange frontal shield. Females however are mostly rufous brown with cinnamon-brown head and neck and a grey beak. Males have dull orange legs whereas the females’ are greenish grey.  One of the things I love about this species is the dorsal fin-like feathers the males have on their back.

    If you are out birding, sight is not the only weapon in your armoury. Knowing what a species sounds like can be extremely helpful when trying to identify it, especially if they are just out of sight. For this purpose I have always found Xeno Canto to be a great resource.  Below is an example of some King Eider calls, more of which can be found on Xeno Canto.

  • King Eiders are seasonally monogamous, although males can mate with more than one female. Breeding starts between June and July with nests being scrapes in the ground (typically near water) lined with feathers (I bet that is one comfy nest) and plant material. Clutches of olive/olive-buff eggs (average 4-5 eggs) are incubated by the female alone and take around 22-24 days to hatch.  Typically only one brood is laid.  Chicks are precocial and are able to leave the nest soon after hatching, feeding themselves.

    Chicks fledge and become independent around 50-60 days after hatching and sexually mature after three years. Crèches, supervised by 1+ females, are sometimes formed by broods.

    Female King Eider

    Female King Eider

  • This species feeds predominantly by diving, often in groups, typically to depths of 25m but up to 55m (that is the height of the Tower of Pisa!). It does also feed in shallow waters through sieving and probing.  Its diet consists of crustaceans, insect larvae, molluscs, echinoderms and plant material. They do however partake in some fishing and here is a lovely picture of a male munching on a herring.

    Array of seabirds including the King Eider from the Birds of North America

    Array of seabirds including the King Eider from the Birds of North America

     

  • Although the number of King Eiders is in decline, due to the vast number of individuals of the species (~850,000), it is listed as “Of Least Concern” on the IUCN Redlist.

    King Eiders are predated by a number of species both as eggs and when they are young. These include: artic foxes, parasitic jaegers, the common raven and the glaucous gull.

    Arctic Fox

    Arctic Fox

    As eggs and young, king eiders have many predators, including: the glaucous gull; common raven; parasitic jaeger and Arctic fox. Pollution and hunting are also major problems for this species, with a quick Google image search for “king eider duck” producing many proud hunters with their catch.

  • The aim with this section is to provide some interesting links for you to check out if you are interested in learning about more about this species. This can come in many forms, from scientific journal articles to popular science blog articles or even just some cool videos that we have found.

    So far I have not found a great deal of extra reading on the King Eider so I thought I would go off on a tangent here and talk about the wonders of the Birds of America (by French naturalist and painter John James Audubon). The reason I take this tangent is because of the fantastic colour plate that you can see under the “Diet” tab.  This plate is not from the Birds of America but you can’t talk about the wonders of colour plates without going back to Audubon’s seminal work.

    The Birds of America was the fruit of Audubon’s desire to paint every single bird in America. It was printed in series between 1827 and 1838 and in total 435 plates were made. The plates featured now extinct species such as the passenger pigeon and the great auk as well as beautiful depictions of American flamingos, great horned owls and many other species.

    Audubon made the drawings from birds (dead of course) held in position with threads and wires and set in backgrounds of their natural habitats.  All of the birds were drawn, or engraved to be more accurate, life-sized, with Audubon contorting larger birds so that they would fit.

    Audubon-gif-2

    Some of Audubon’s magnificent colour plates

    Audubon’s work is still a masterpiece to this day and the fact that 3 of the 10 most expensive books of all time are first editions of his work is testament to this. The most recently sold copy was bought in 2010 for more than £7million in London at Sotherby’s.

    I fully encourage you to log onto the audubon website where you can see the plates for yourself and read more about this fantastic piece of work.  There is also more information about each species in the book if you want to read up on them.

    To link it back to the original subject, the King Eider, you can follow this link to zoom in on Audubon’s take on them (no it isn’t my Ebay account).

References

BirdLife International. 2012. Somateria spectabilis. The IUCN Red List of Threatened Species 2012: e.T22680409A40146039. http://dx.doi.org/10.2305/IUCN.UK.2012-1.RLTS.T22680409A40146039.en. Downloaded on 03 February 2016.

Carboneras, C. & Kirwan, G.M. (2016). King Eider (Somateria spectabilis). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from http://www.hbw.com/node/52915 on 2 February 2016).

Suydam, R. S. 2000. King Eider (Somateria spectabilis). In The Birds of North America, No. 491 (A. Poole and F. Gill, eds.). The Birds of North America, Inc., Philadelphia, PA.

Images and Videos

Arctic Fox by A Neumann is licensed under CC BY-NC 3.0.

Audubon’s Colour Plates by Johan Audubon is licensed under Public Domain Mark 1.0.

BirdLife International and NatureServe (2014) Bird Species Distribution Maps of the World. 2012. Somateria spectabilis. The IUCN Red List of Threatened Species. Version 2015-3

Female King Eider by Ómar Runólfsson is licensed under CC BY 2.0.

King Eiders taking flight by Ron Knight is licensed under CC BY 2.0.

groenelantaarn. 2013. King Eiders. Online. 04/02/2016. Available from: https://www.youtube.com/watch?v=QK9qZHa79Do.

Seabird plate from Birds of North America is licensed under CC BY 2.0.

Audio

Andrew Spencer, XC141727. Accessible at www.xeno-canto.org/141727

The Masked Flowerpiercer (Diglossa cyanea)

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This beautiful member of the Thraupidae (tanager) family proved to be a difficult species to identify on #BeakoftheWeek.

Diglossa cyanea

Diglossa cyanea

This large flowerpiercer is easily identifiable with its striking ultramarine plumage, red eyes and black mask. It is slightly larger than a great tit at 15cm and weighs between 12 and 22.5g.  Females are similar to males but slightly duller, with juveniles duller still and greyish.

The bill of this species is long and slender with a slight upturn and a small hook at the end of its upper mandible.  This small hook is sometimes used to pierce flowers and fruits to get to their internal nutrients, which is where the name “flowerpiercer” comes from.  More often than not it feeds on fruits and berries (particularly Melastomataceae species) and some insects.

This species is highly sociable often found in monospecific groups of up to 30 individuals, as well as in mixed flocks of tanagers, other flowerpiercers, warblers and others.  They are found in cloud forests (usually above 2000m) of North Western South America from the coastal mountains of Northern Venezuella to Northern Bolivia.

This species breeds at varying times across South America, with immatures reported nearly all year round. They lay their eggs in feather-lined open cup nests made of moss, grass and feathers, usually in bushes. Unfortunately no more information is available on the breeding methods of this species. Seems to me like someone should head out on an expedition…

The songs of this species remind me of those of fairy wrens in Australia.  You can have a listen to one singing below, or you can navigate yourself to Xeno Canto for a greater range of flowerpiercer songs.

I have managed to find a few videos of the masked flowerpiercer, and I am rather fond of this one of one feeding some chicks on the internet bird collection.  In fact the IBC has got loads of fantastic videos of this species doing all sorts of things. A nice way to while away five minutes or so.  I couldn’t get those videos into my post, so here is one I found on the ever reliable youtube to whet your appetite.

Good news relating to the status of this species as it is listed as of Least Concern on the IUCN redlist due to its large range size and the belief that its population size does not approach the thresholds for vulnerable.

Last but not least you can check out what species this fellow is most related to on OneZoom by clicking this link.

References

. 2010. Masked Flowerpiercer (Diglossa cyanea), Neotropical Birds Online (T. S. Schulenberg, Editor). Ithaca: Cornell Lab of Ornithology; retrieved from Neotropical Birds Online: http://neotropical.birds.cornell.edu/portal/species/overview?p_p_spp=637356.

BirdLife International. 2012. Diglossa cyanea. The IUCN Red List of Threatened Species 2012: e.T22723715A40010593. http://dx.doi.org/10.2305/IUCN.UK.2012-1.RLTS.T22723715A40010593.en. Downloaded on 03 December 2015.

Hilty, S. (2011). Masked Flowerpiercer (Diglossa cyanea). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.) (2014). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from http://www.hbw.com/node/61776 on 3 December 2015).

Images and videos

Diglossa cyanea by Ken-ichi ueda is licensed under CC BY-NC 3.0.

Nikhil Patwardhan. 2015. Masked Flowerpiercer – Guango Lodge. Online. 03/09/2015. Available from: https://www.youtube.com/watch?v=Q-nLkj9G_-A.

Audio

Jerome Fischer, XC234634. Licensed under CC BY-NC-SA 4.0. Accessible at: http://www.xeno-canto.org/234634.

The Hamerkop (Scopus Umbretta)

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Another one of my favourite birds came up for this episode of #BeakoftheWeek.

Hamerkop flying

Hamerkop flying

As instantly recognisable as horse in a dog show, there is no mistaking the Hamerkop. With its hammer-like head (hence the name) and cocksure strut, this bird seemingly knows it is something special.

The hamerkop is endemic to sub-saharan Africa and Madagascar and is usually found around wetlands foraging in shallow waters for frogs, tadpoles and small fish.  The “peacocking” that this species exhibits is added to by the purple iridescent gloss on its back that stands out from its brown plumage.

They are not shy and many pictures and videos that I have found show it happily fishing in the company of crocodiles and chilling out on the backs of hippos.

Scopidae is a monotypic family, with the hamerkop being the only member.  Its closest relative is the intimidating Shoebill stork, of BBC Africa fame and the stuff of nightmares.  If you click this handy link to OneZoom you can peruse other close relatives of this species.

Standing are around 50cm and weighing just under half a kilo, this species is a medium sized wading bird.  It has partially webbed feet and a comb-like (pectinated) middle-toe that it uses to groom.  Here is a nice short article on pectinate toes if you wish to read more.

The Hamerkop is known to breed all year round in Eastern Africa although breeding times vary across the rest of the continent.  This species is famed for its penchant of building large elaborate nests which I will go into shortly.  They normally lay 3-6 eggs which take around 30 days to hatch and a further 44-50 days to leave the nest.

Hamerkop chilling on the back of a hippo whilst snacking on an amphibian treat.

Hamerkop chilling on the back of a hippo whilst snacking on an amphibian treat.

The internet bird collection has a charming picture of a 7 day old chick which I highly recommend taking a look at.

The monstrously large nest that this species builds can weigh between 25 and 50kg and stand up to 2 metres high and 2 metres wide.  This behemoth of a nest, made up of thousands of twigs, takes between 3 and 6 weeks to build. A serious amount of effort goes into making a nest of that size, which makes the fact that a pair can build numerous nests, some of which will never be used, even more impressive.  I think they are the avian equivalent of that friend who always has to out-do your achievements.  Although saying that you would have to try hard to get noticed if a Shoebill was your closest relative.

Hamerkops are known to be quiet when on their own, but vocal when in the company of others.  You can have a listen to some below, or you can head over to Xeno Canto for a greater variety of audible delights.

I was pleased to see that this species is of Least Concern on the IUCN redlist due to its very large range and population size.  This may be helped by the following…

As I have mentioned before, we here at team MacroBird love myths and legends, and one that has persisted about this species is that you will get struck by lightning if you steal from its nest.  This has led to it being dubbed the ‘lightning bird’ by the Kalahari bushmen.  I have even read tales of how you can get Leprosy from destroying their nests.  I think what we have learnt here is that it is best to just stay away from their nests altogether.

References

BirdLife International. 2012. Scopus umbretta. The IUCN Red List of Threatened Species 2012: e.T22697356A40280654. http://dx.doi.org/10.2305/IUCN.UK.2012-1.RLTS.T22697356A40280654.en. Downloaded on 02 December 2015.

Elliott, A., Garcia, E.F.J. & Boesman, P. (2014). Hamerkop (Scopus umbretta). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.) (2014). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from http://www.hbw.com/node/52732 on 2 October 2015).

Images and Videos

Hamerkop flying taken by Mattias Hofstede, IBC238943. Accessible at ibc.lynxeds.com/node/238943.

Hamerkop on Hippo taken by David Cantrille, IBC257371. Accessible at ibc.lynxeds.com/node/257371.

Helen Kavanagh. 2012. Group of Hammerkop birds in the maasai mara. Online. 02/12/2015. Available from: https://www.youtube.com/watch?v=vacI9VT_NbE.

Audio

Andrew Spencer, XC269286. Licensed under CC BY-NC-ND 4.0. Accessible at http://www.xeno-canto.org/269286.

The Eurasian/Winter Wren (Troglodytes troglodytes)

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Wren calling

Wren calling

For us Brits, this is THE wren, perhaps unsurprisingly as it is the only member of its family (Troglodytidae) found in the Europe (and Africa) and indeed the only one found outside of the Americas.  You’ll find them across the UK and much of the Northern hemisphere, they are usually flitting around voicing their distinctive calls and they are easily noticed on a woodland walks.  They are the most common breeding bird in the United Kingdom with an estimated 8,600,000 breeding pairs (wow!) and recently came 4th in a poll to find Britain’s national bird, losing out to the Robin – there are worse birds to lose to!  Its popularity probably goes some way to explaining how quickly someone identified it on #BeakoftheWeek.

It is on the small side measuring around 10cm long and weighing 6-12g (so about the same as a £1 coin). The sexes are similar in appearance but if you see one singing it is likely to be a male as the females are not known to sing, although recent work has shown that other female songbirds do indeed sing.  They mostly eat invertebrates such as spiders and earwigs and small vertebrates such as small fish and tadpoles.  They have also been known to eat vegetable matter such as berries.  You can most often see them foraging low on the ground in vegetation.

A common behaviour seen in many species when breeding is that the males will build numerous nests and the female will then check them all out before choosing her favourite to lay her eggs in.  The nests of this species are made from grass and fibres and are domed with side entrance holes. The female adds lining to these structures before she starts to lay. Laying begins around late march/early April and lay on average 5-8 eggs. The female incubates these alone and after 16 days some cute little chicks will emerge. On average the chicks leave the nest 17 days later and become fully independent of their parents 9-18 days later.  Both parents take responsibility with chick feeding.

This species is not sexually dimorphic although differences in colouration, size and plumage barring has led to there being over 30 different subspecies classified worldwide.  You’ll find these guys all year round in the UK and they tend to be residential, with ring recoveries showing movements of only 50km or less. Polygamy is quite frequent in western populations .

Feeding Time

Feeding Time

They have got to be one of my favourite birds to come across with their calls that are curiously loud for such a small creature, so I am pleased to say that it is of ‘Least Concern’ on the IUCN redlist.  Given how abundant this species is in the UK alone it is no shock to learn this. One more interesting fact about the wren is that its name “troglodytes” means cave dweller or hermit.  Perhaps why although it is the commonest bird in the country it most certainly isn’t the one we will see the most of.  The little skulker.

Okay a few more snippets about this great little bird. It appeared on the farthing and in European folklore it is know as the king of birds. How did it receive this esteemed title?  Well of course it was by having a battle with an Eagle to see who could fly highest and by having the cheek to sit on the back of its adversary, therefore taking it highest.  They say cheats never prosper…

You can head to OneZoom if you want to check out how related the wren is to your favourite bird species.

Here’s an example of one of their calls that can be found on Xeno Canto to get you started. For more follow the earlier link.

 

References

BirdLife International 2014. Troglodytes troglodytes. The IUCN Red List of Threatened Species. Version 2015.2. <www.iucnredlist.org>. Downloaded on 03 September 2015.

Kroodsma, D., Brewer, D., Christie, D.A. & Bonan, A. (2013). Northern Wren (Troglodytes troglodytes). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.) (2013). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from http://www.hbw.com/node/58150 on 3 September 2015).

RSPB. 2015. Wren. Online. 04/09/2015. Available from: http://www.rspb.org.uk/discoverandenjoynature/discoverandlearn/birdguide/name/w/wren/.

Images and Videos

Feeding time by Sonja Kübelbeck is licensed under CC BY-SA 3.0.

WIld Bird Video Productions. 2011. Winter Wren. Online. 03/09/2015. Available from: https://www.youtube.com/watch?v=qw-NqhxwGWQ.

Wren calling by Biopix is licensed under CC BY-NC 3.0.