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 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.

 

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.

The Rifleman (Acanthisitta chloris)

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The Rifleman or Titipounamu is one small bird, thought to be New Zealand’s smallest in fact, measuring between 6-7g and only 7-9cm long.  It is endemic to New Zealand and is one of only 2 surviving members (originally 6) of the New Zealand Wren family (Acanthisittidae) along with the Rock/South Island Wren.  Like a lot of the smaller species, this proved a tricky one on  #BeakoftheWeek.

The Rifleman sounds like it belongs on the front line, which is unsurprising given that its name apparently stemmed from a resemblance to a regiment in the New Zealand armed forces.  Although it looks like a member of the true wren family (Troglodytidae) or a fairy-wren (Maluridae) it is not related to either.  You can have a look where it sits in the avian phylogeny on OneZoom.

Male Rifleman in a flap

Male Rifleman in a flap

This species is sexually dimorphic and you can see in these pictures the clear differences between the males and females.  They are monogamous with long-term pair bonds and are cooperative breeders, with helpers, usually offspring from previous breeding seasons, aiding them with feeding chicks and other duties.

Breeding occurs between August and February. Enclosed spherical nests are built in existing cavities, with the lion’s share carried out by the male.  2-5 eggs are laid that take ~20 days to hatch and a further 24 days for the chicks to fledge.  Incubation and nestling and fledgling feeding duties are shared between the breeding pair with some help from helpers with feeding.

Rifleman are insectivorous and partial to tasty treats such as spiders, moths and butterflies, flies and wingless crickets.  They forage in pairs or small groups, rarely alone.  They rarely forage on the floor and take most of their prey from trunks, branches and twigs. As poor fliers they mostly just make short flights between the canopy.

If you are on a trip to New Zealand to seek one of these chaps out then you should head to some mature forests, and listen out for some of these songs on Xeno Canto.  They are of ‘Least Concern’ on the IUCN redlist, although their population is said to be in decline due to habitat destruction and introduced pests such as stoats.

The final piece of the puzzle if of course seeing them in action if you are not lucky enough to be on an adventure to New Zealand.  Below is a nice video showing some great close-ups of a male at a nest box:

 

References

BirdLife International 2012. Acanthisitta chloris. The IUCN Red List of Threatened Species. Version 2015.2. <www.iucnredlist.org>. Downloaded on 01 September 2015.

BirdLife International (2015) Species factsheet: Acanthisitta chloris. Downloaded from http://www.birdlife.org on 01/09/2015.

Gill, B. (2004). Rifleman (Acanthisitta chloris). 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/57585 on 1 September 2015).

Withers, S. 2013. Rifleman. In Miskelly, C.M. (ed.) New Zealand Birds Onlinewww.nzbirdsonline.org.nz

Images and Videos

“Acanthisitta chloris chloris” by Jon Sullivan is licensed under CC BY-NC 3.0.

EYESEALAND Visual Media. 2010. Rifleman on Tiritiri Matangi Island. Online. 01/09/2015. Available from: https://www.youtube.com/watch?v=-dcGm5S-gyA.

“Suffolk Stoats” from wikimedia commons is licensed under CC BY-SA 3.0.

The Lammergeier (Gpyaetus barbatus)

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Lammergeier 1

Lammergeier in flight

A recent #BeakoftheWeek favourite and a creature of many names, the Lammergeier, Bearded Vulture or Ossifrage (“bone breaker”) is an intriguing bird in many ways.  Not only does it have a rather extravagant method of preparing its food, it is also a bit of a fan of bronzing up to improve its image. If that is not enough to pique your interest then it is surrounded by myth and legend, something we at team Macrobird are rather fond of.

In Iranian mythology the Lammergeier is a symbol of luck and happiness, and if its shadow falls upon someone it is believed that they will rise to sovereignty. In Southern Europe they sometimes feed on tortoises and there have been tales of unfortunate balding men being confused with rocks and coming a cropper to these reptilian projectiles dropped from above. Aeschylus, a Greek playwright, is believed to have been killed by one of these cheeky chaps dropping a tortoise on his head in around 455BC, a rather dramatic way to go even for one so fond of theatrics.

Where does the Lammergeier get all its names from? Well I think the bearded vulture is fairly self explanatory with “facial hair” that gives you a good insight into how carefully this species takes care of its appearance. Its fondness for lambs explains why it is call the Lammergeier as it means ‘lamb vulture’ in German.

As mentioned earlier this species has a rather special way of preparing its food, to break it down to a manageable size, leading to it being known as the Ossifrage/bone breaker.  Bones make up up to 90% of their diet which is supplemented by carcasses of small and medium sized animals such as rodents, small carnivores and reptiles.  They eat both the bones and bone marrow and in order to get the pieces small enough to ingest they have to get creative.  I thought you’d enjoy the dulcet tones of Sir David explaining the process of their bone dropping antics rather than reading about it, so have a watch of the video below to learn more.

If you have watched the video you might be wondering how they manage to digest these bones in order to obtain nutrients.  Fortunately for us some lovely scientists have figured out that it is due to the high acidity (~1 on pH scale) of their stomachs which allows them to break down bones over a period of 24 hours.  Here is the paper if you fancy some further reading.

This species is rather fond of keeping up appearances and they maintain their orange appearance by rubbing minerals (iron oxide particles) into their feathers through sand bathing or wall-rubbing.  This paper discusses this in more detail.  Further to their fanciful looks is their facial feathers which are rather unique as most other vulture species have featherless heads, something that is discussed in the King Vulture blog article.  If you need some grooming tips, here is a nice video of one having a preen.

Feeding time

Feeding time

Amazingly its impressiveness does not stop there.  It is one of the largest vultures with a wingspan of up to almost 3 metres, stands around 4 feet tall and weighs up to 7kg.  It goes on… Adults have home ranges that can be thousands of km2 and can fly at heights of 8,000m up above the Himalayas.  I think I have finally run out of ‘impressive Lammergeier facts and feats’.

They are monogamous and make their nests on cliffs lined with wool and other material such as animal hair and skin.  Up to 2 eggs are laid which hatch after about 54 days after which one chick will be killed by the aggressive older sibling.  The chick will fledge after 103-133 days and will usually first breed at around 10 years of age.  Individuals have been known to live over 40 years in captivity.

This species is listed as ‘Near Threatened’ on the IUCN redlist due to rapid population decline over the past 3 generations (thought to be 25-29%), although populations in Northern Spain having been rising since 1986.  The biggest threat to this species are habitat destruction and poisoning, both accidental and targeted, and collisions with power lines and wind turbines.  There are thought to be 1,300-6,700 mature individuals in the wild.

The closest living relative of the Lammergeier is the Egyptian Vulture which split away from it over 20 million years ago.  You can explore this species and other closely related ones by checking out this OneZoom link.  Shoot over to Xeno Canto, the avian version of spotify, to have a listen to this species and click here to see where you can spot them potentially tossing bones and tortoises about on a sunny afternoon (range map).

References

BirdLife International 2014. Gypaetus barbatus. The IUCN Red List of Threatened Species. Version 2015.2. <www.iucnredlist.org>. Downloaded on 10 August 2015.

BirdLife International (2015) Species factsheet: Gypaetus barbatus. Downloaded from http://www.birdlife.org on 11/08/2015

Orta, J., de Juana, E., Marks, J.S., Sharpe, C.J. & Garcia, E.F.J. (2015). Bearded Vulture (Gypaetus barbatus). 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/52992 on 10 August 2015

Images & Videos

Feeding time” by Francesco Veronesi is licensed under CC BY-NC-SA 2.0.

Lammergeier in flight” by Noel Reynolds is licensed under CC BY 2.0.

funvidpg. 2015. BBC Life Lammergeier. Online. 12/08/2015. Available from: https://vimeo.com/121888799.

The Tooth-Billed Pigeon (Didunculus strigirostris)

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Tooth-billed pigeon mount

Tooth-billed pigeon mount

This is the first critically endangered species to be included on the #BeakoftheWeek blog.  The tooth-billed pigeon is endemic to the Samoan islands of Upolu and Savai’i (where is it known as Manumea) and is one of the closest relatives to the legendary extinct dodo.  This fascinating pigeon is nicknamed the ‘little dodo’ and unfortunately relatively little is known about it.

The tooth-billed pigeon is an EDGE (Evolutionarily Distinct & Globally Endangered) species and it is believed that there is only between 50-249 mature individuals left in the wild.  Drivers of declines in numbers are habitat destruction (logging and cattle ranches), hunting, invasive species and damage by cyclones during the 1990s.

It is the national bird of Samoa and is legally protected from hunting although this is not enforced. Conservation efforts are targeted at bringing this species back from the brink of extinction, such as habitat restoration and extending hunting bans to including all native pigeons to prevent accidental killing. Establishment of captive populations and translocation to rat-free islands are also being considered as possible steps.

The Dodo, unfortunately extinct but manages to be one of the most well known birds ever to have existed.

The Dodo, unfortunately extinct but manages to be one of the most well known birds ever to have existed.

Little is known about breeding in this species except that they are thought to nest in thick foliage about 5-12m from the ground and lay 2 eggs per clutch.

I can offer you up some good news today! Back in 2013 a juvenile tooth-billed pigeon was photographed on Savai’i which means that they are still breeding even though they are not being spotted very often.  Hopefully conservation efforts will lead to an increase in this species’ numbers in the near future so that we don’t lose them forever.

No Xeno Canto links calls are available for this species unfortunately, so you will have to sit back and enjoy this cool OneZoom animation and explore their nearest relatives.  Definitely recommend taking a peak at the Nicobar pigeon, I do love that pigeon.

References

Baptista, L.F., Trail, P.W., Horblit, H.M., Kirwan, G.M. & Sharpe, C.J. (2014). Tooth-billed Pigeon (Didunculus strigirostris). 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/54282 on 20 July 2015).

BirdLife International (2015) Species factsheet: Didunculus strigirostris. Downloaded from http://www.birdlife.org on 20/07/2015.

Images

“Tooth-billed pigeon mount” by Gunnar Creutz is licensed under CC BY-SA 4.0.

“The dodo” by Biodiversity Heritage Library is licensed under CC BY-NC-SA 2.0.

The Prong-Billed Barbet (Semnornis frantzii)

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Time for another #BeakoftheWeek species profile! We’re hitting up the Semnornithidae family today with the prong-billed barbet.

Prong-billed barbet

Prong-billed barbet (Semnornis frantzii)

The prong-billed barbet is confined to a small range between the Caribbean slope of Costa Rica and western Panama.  You will usually encounter them foraging in the forest canopy in pairs or in groups of 12+ birds.

Although not the biggest of birds at 18cm and around 60g, or the most flamboyantly coloured, they do have a fancy beak, which you might expect given their name.  There beak is a little unusual given that there are two little prongs on the lower mandible and a hook on the upper mandible that fits between them. I am yet to find out why this is, but when I do I will be sure to let you know.  I do know that they are mainly frugivorous with the odd insect thrown in for good measure.

The pair excavate dead trees or branches between 3 and 18m high to make their nests over 8 days in which 4-5 eggs will be laid.  Both adults incubate that eggs over 14-15 days and then take care of feeding and brooding duties between them after their altricial chicks hatch.  The pair actively defends their territory during the breeding season (March to June).

This species is of ‘Least Concern’ on the IUCN redlist as it is common within its range.  Check out this link to a website I am sure you all know by now for some prong-billed calls.  Also a new feature for the blogs is this onezoom link which I will let you explore for yourselves.

References

BirdLife International 2012. Semnornis frantzii. The IUCN Red List of Threatened Species. Version 2015.2. <www.iucnredlist.org>. Downloaded on 10 July 2015.

Buckio, Brandon. 2011. Prong-billed Barbet (Semnornis frantzii), 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=298456.

Short, L.L., Horne, J.F.M. & Kirwan, G.M. (2013). Prong-billed Barbet (Semnornis frantzii). 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 fromhttp://www.hbw.com/node/56068 on 10 July 2015).

Images

Prong-billed barbet” by Flickr-user Clickor is licensed under CC BY 2.0.

The Marabou Stork (Leptoptilos crumenifer)

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Marabou stork

Marabou stork

The Marabou stork is the bird of choice today, a member of the Ciconiidae family.

An absolute beast of a bird, this former #BeakoftheWeek candidate can grow as tall as Kylie Minogue (range 115-152cm) and has one of the biggest wingspans of all birds (2.25-2.87cm). It is not just its appearance that makes it an intimidating creature as its feeding strategies have led to it being christened as the “Undertaker Bird”. It feeds on carrion and can been seen mixing amongst vultures at large predator carcasses.  One interesting technique that they employ to catch their prey, which could definitely be classed as rather cruel, is to wait near grass fires and grab animals as they emerge. A case of out of the fire and straight to the undertaker.

This species has a wide range across central and southern Africa inhabiting grassland, open dry savannah, river banks, near fishing villages and also around rubbish dumps and slaughterhouses.  They are opportunistic feeders, and the unsuitability of their beaks to dismembering carcasses leads to them taking scraps from vultures and other predators or eatting things that are dropped.  Their diet is varied with them feeding on birds, invertebrates, rats and lizards.  They are also adept fishermen, fishing by sight and by submerging their partially open beak and snatching them up.

Marabou scavanging

Marabou scavenging

The number of birds in a colony can be in the thousands, but usually 20-60 pairs, with breeding season varying between the tropics and equatorial zones. In the tropics it begins in the dry season and ends in the rainy season, whereas it is more variable around the equator.  They usually make their nests in trees 10-30m off the ground out of twigs and green leaves.  Typically they lay 2-3 eggs that take ~30 days to hatch and then a further 95-115 days to fledge.

Global population was estimated at between 200,000-500,000 in 2006 and it is thought that these numbers are increasing as it utilises its ability to exploit rubbish dumped by humans. This species is of least concern on the IUCN redlist.  It is thought that its perceivably unattractive appearance could be making it less appealing to hunters and knowledge that they play an important role in clearing up rubbish and carcasses, helping to prevent disease, may stop people from targeting them.

Xeno canto once again has a few calls for you to listen to and OneZoom is a fantastic little site that lets you explore where this species sits in the tree of life.

 

References

BirdLife International (2015) Species factsheet: Leptoptilos crumenifer. Downloaded from http://www.birdlife.org on 10/07/2015.

Elliott, A., Garcia, E.F.J. & Boesman, P. (2014). Marabou (Leptoptilos crumenifer). 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 fromhttp://www.hbw.com/node/52751 on 10 July 2015).

Images and videos

Marabou stork” by Dr. Lloyd Glenn Ingles is licensed under CC BY-NC-SA 3.0.

Marabou scavenging” by  Brocken Inaglor is licensed under CC BY-SA 3.0.

5cense. 2007. Marabou Storks Eating, Grooming, Mating & Generaly Brooding. [Online]. [10/07/2015]. Available from: https://www.youtube.com/watch?v=wuwbPyTtG1k.

 

3D scanningbeak of the week,beakoftheweekbird morphologybirdscool,Double-toothed kite,factsHarpagus bidentatus,macroevolution

The Large Ground Finch (Geospiza magnirostris)

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Large ground finch pair

Large ground finch pair

Today we’re talking about a challenging past #BeakoftheWeek nominee, the large ground finch. As the name suggests this species has a rather large bill relative to its body size and is often as deep as it is long.  You can see why it has been charmingly nicknamed ‘Megamouth’.

Amongst the most famous groups of birds in the world, this species has the honour of being one of Darwin’s finches. Here is a nice brief recap on Darwin’s finches, and a great little graphic showing their different bill shapes and diet.  This clip talks about them further whilst showing some of the different species.

Endemic to the Galapagos Islands off of the West coast of Ecuador, they are found in arid scrub and lowland areas on many of the islands. .

These birds use their big beaks to feed on caterpillars, fruits and large seeds.  Males are almost entirely black with slightly browner wings and tail, and females are dark brown with sandy-buff fringing. They are about 15cm long and weigh around 35g.

Large ground finch male

Large ground finch male

This species is usually monogamous and tend to mate after the first rains of the season. Nest building is carried out by the male who constructs a sphere made from dry grass and other vegetation with a lateral entrance near the top.  The pair can lay up to 4 clutches in one season, which usually consists of 4 eggs that take about 12 days to hatch.  The nestlings leave the nest after around 14 days.

This species is of least concern on the IUCN redlist, and population numbers are said to be stable.

Xeno Canto has a solitary song for them, and you can reacquaint yourself with exactly where the Galapagos Islands are by following the link.

References

BirdLife International 2012. Geospiza magnirostris. The IUCN Red List of Threatened Species. Version 2015.2. <www.iucnredlist.org>. Downloaded on 06 July 2015.

BirdLife International (2015) Species factsheet: Geospiza magnirostris. Downloaded from http://www.birdlife.org on 07/07/2015

Jaramillo, A. & Christie, D.A. (2013). Large Ground-finch (Geospiza magnirostris). 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/62175 on 6 July 2015).

. 2010. Large Ground-Finch (Geospiza magnirostris), 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=632076

Images

Large ground finch male” by Gerald and Buff Corsi is licensed under CC BY-NC-SA 3.0.

Large ground finch pair” by John Gould is licensed under Public Domain Mark 1.0.

The Double-Toothed Kite (Harpagus bidentatus)

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Time for some more information on a past #BeakoftheWeek star, the double-toothed kite.

Now everyone loves a kite, both the kind you run around with on a sunny day and the ones you see soaring overhead in places like Hertfordshire.  We often see red kites hovering around the museum in Tring during our breaks.  The double-toothed kite is something special however…

They are named for after the presence of two tomial “teeth” on the edge of their upper mandible.  Their wingspan reaches around 65cm and they are 29-35cm tall. Females are slightly bigger than males at 190-229g (males 161-198g).

Double-toothed kite. You can just about make out the teeth in this photo.

Double-toothed kite. You can just about make out the teeth in this photo.

When hunting this species uses a clever trick of following monkeys through the canopy waiting for them to disturb insects and lizards, which they will then catch and eat.  A nice way of getting someone else to work for your dinner.  It is seemingly a parasitic relationship as there is no apparent benefit to the monkeys, although the presence of this kite may help protect them against larger birds of prey.  They have a preference for monkeys that tend to move extensively whilst foraging instead of sitting idly for long period, which makes sense if they are hoping they will flush out tasty treats.  They are also known to eat snakes, birds and rodents amongst others.  Unfortunately I cannot find a video of this interesting behaviour.

Here is a nice, if old, paper on the association between this species and white-faced capuchin monkeys.

This species has a large range, stretching from southern Mexico through much of northern south America. Its breeding season varies across the range but tends to be between April and July. The female is thought to incubate and brood the chicks alone although the male provides much of the food during incubation and early nestling period.  The female carries out the lions share of nest construction, building a nest out of twigs in the fork of a tree between 7 and 33m from the ground. Females typically lay 2 eggs which take 42-45 days to hatch and then the chicks usually leave the nest after 27-31 days.  Within two months the young are independent of their parents.

You can once again head straight over to Xeno Canto to complete your experience with some bird of prey calls.

References

BirdLife International (2015) Species factsheet: Harpagus bidentatus. Downloaded from http://www.birdlife.org on 09/07/2015.

Bierregaard, R.O., Jr, Marks, J.S. & Kirwan, G.M. (2015). Double-toothed Kite (Harpagus bidentatus). 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 fromhttp://www.hbw.com/node/52973 on 9 July 2015).

. 2010. Double-toothed Kite (Harpagus bidentatus), 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=120636

Images and videos

Double toothed kite” by joule_e is licensed under CC BY-NC-SA 2.0.

Victor castro. 2012. Double-toothed Kite (Harpagus bidentatus) . [Online]. [09/07/2015]. Available from: https://www.youtube.com/watch?v=RMWPaZ8kSE4