Which Eagle is the biggest? (Questions my grandkids ask me)
Which is the biggest Eagle in South Africa?
(Questions my grandchildren asked me.)
Children are always asking interesting questions and the boys always want to know what is bigger? Seeing birds there are obviously differences in size and in teaching bird identification the first question to ask is, "how big is it?"
Well known birds in an area provide guidelines as to the size of a bird needing identification. Is it the same size as a sparrow, dove, guinea-fowl or crane? This helps us on the first step in identifying a new bird. Now we can move on to the kind of beak the bird has. That will give us a clue as to what it eats. Obviously a seed-eater will have a different beak to a meat eater and a sunbird will have a long pointed beak to search in flowers for pollen. The kingfisher family have long beaks for catching fish although it is interesting to note that not all kingfishers actually catch fish, as the beautiful Oyster-catcher also do not really eat all that many oysters as their name would imply.
When it comes to the size of similar birds like the Eagles it can in fact be difficult to determine which is biggest.There is some debate on the issue and I guess it all depends on how you measure them. Sometimes a simple question is not so simple to answer! There are three contenders for the larges Eagle in Southern Africa: (1) In the Black Corner is the Verreauxs’ Eagle also known as the Black Eagle because of its color. (2) In the White Corner is the Martial Eagle. (3) Finally in the Black and White corner is the Crowned Eagle. Some birding guide books claim that one is the largest and others differ.
There are three vital measurements: wingspan, height and weight. The tallest are the Verreaux’s Eagle (80-90cm.) and Crowned (80-96 cm). The heaviest are the Martial Eagle (2.4-5.2 kg.) and the Verreaux’s (3-5.6 kg.). The largest wingspan belongs to the Martial Eagle (212 cm.) and the Crowned(200 cm.) Just to make the debate more interesting one Field Guide claims that the Crowned Eagle is the “most powerful”, but I am not certain how they measured that.
You will have to decide for yourself who you would vote for in this competition! In my opinion it may be a draw on points, but all three are beautiful and magnificent.
In their beautifully illustrated and expertly written book on Southern African Birds of Prey, Peter and Beverly Pickford and Warwick Tarboton give the position of largest African Eagle to the Martial Eagle and who am I to disagree with such experts. At the same time they claim that the Crowned Eagle is considered to be the most powerful of the Eagles.. It has been recorded to have taken a Bushbuck of an estimated 30kg as prey.
Just to make things more interesting none of the field guides agree absolutely on these measurements. As someone asked, how do you measure eagles anyway?
(References: Sasol, Birds of prey of Africa and its Islands by Alan and Meg Kemp; The Bird Guide of Southern Africa by U. Oberprieler and B. Cillie; Complete Photographic Field Guide BIRDS of Southern Africa I. Sinclair and P. Ryan; Roberts’ Birds of Southern Africa, G.L.Maclean)
It is also interesting to compare the beautiful Bald Eagle from the USA at a height of 86 cm and a wingspan of 2 m. and the Golden Eagle 89cm and wingspan of 2.1m. (Field Guide to Birds of North America, E.S. Brinkley) Another interesting fact is that the female is always larger than the male.
