The Lammergeier (Gpyaetus barbatus)

facebooktwitter

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.