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Could a haast's eagle really kill an adult human?
Topic Started: Dec 21 2012, 10:15 AM (10,402 Views)
Mulawin
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Posted Image

A determined eagle who would attack a human can inflict fatal injuries and can kill.


Edited by Mulawin, Dec 23 2012, 03:00 PM.
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adznz11
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Black Ice
Dec 21 2012, 11:22 AM
Rashido
Dec 21 2012, 11:03 AM
Black Ice
Dec 21 2012, 10:48 AM
Yes. Wait.... The neanderthal humans or H. Sapien? Neanderthal IMHO no, too tough and strong. Regular H. Sapien yes.
There were no Neanderthals in New Zealand.... :huh:
He said human......
Actually there is strong evidence of human predatation by the Haast's eagle. The Haast's was an evolutionary pre adapted large (much larger than humans) bipedal prey predator. When the maori hunted the moa (haast's natural prey) to extinction during that proccess of a fast decline in natural prey and a sharp increase in the smaller large prey (man) it would have been biologically not only probable but necessary that the haast's would have seen man as a viable alternate prey source. They still had hungry chicks to feed. Also maori folk lore tells of a terror from the skys and there is archaeological evidence of traps made specifically for trapping large Ariel predators in this country. It was very likely that this helped speed the demise of the Haast's eagle as the fear of the eagle passed down by oral record certainly points to and more than likely the active hunting of the eagle by the maori people out of true fear. I love predators and was always jealous of other country's cool animals and thought i was born in the most boring (wildlife wise) country in the world until i discovered the haast's eagle the fact that i already loved raptors only made it better. I don't think there was anyway the haast's would have been able to stay in the same world as us considering the only way it achieved the size it had was due to the complete lack of predators in the first place + the fact it is just to dam dangerous for us to allow a huge ariel predator that could and would kill us for food. It still makes me sad though. I would give any thing to see this king of raptors fly through our native bush. It is the reason that most of our medium sized native birds are nocturnal. The ghost of the largest flying killer still lingers here and in my mind i can still imagine it when i look upon our land.
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DinosaurMichael
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If it can kill a 600 pound Moa. I don't see why it couldn't kill a Human....
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Arovinrac
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I think a harpy eagle has around 500 psi grip, so a bigger Haast eagle would have a phenomenal grip, which if positioned around a human skull would kill the human.
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theropod
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Again that psi that doesn't specify the strenght in its talons but just the strenght per area, with lots of variables. For which area? PLEASE guys, stop parrotting newspapers when you actually don know what exactly they are writing. Nobody here has the slightest clue how to interpret those annoying psi figures, because nobody has info on the exact surface area of its feet, or even for which surface it was meant to hold true. It is the absolute force that the msucles can excert that we need to know, not crappy figures with some odd relation to area.

A lion has a lower bite force in psi than a leopard (based on the square cube law at least), however in total it has a much stronger bite. Why? because it's larger!

The psi of a harpy is probably stronger than that of a haasts eagle.

for the actual question, I'm pretty sure a reasonably sized harpagornis could kill an unarmed human. Also, the scene from monsters we met showed a fleeing woman, thatś a different story from a (male) human that is willing to defend itself. But be realistic, if it could kill a moa, it could kill a human.
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Arovinrac
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Roughly how strong were a haast eagles talons?
And apparently I have misunderstood psi strength, what have I misunderstood?
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Ophiophagy
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about the same as a harpy

but they are about the size of a condor


so condor sized bird with harpy feet


small male haast was the exact same as a huge female harpy
Edited by Ophiophagy, Jan 23 2013, 04:59 AM.
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Vivec
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poison
Jan 23 2013, 04:56 AM
about the same as a harpy

but they are about the size of a condor


so condor sized bird with harpy feet


small male haast was the exact same as a huge female harpy

Posted Image

A bit larger actually.
Edited by Vivec, Jan 23 2013, 05:25 AM.
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dracosaurus
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A large eagle such as the African Crowned Eagle could rather easily kill a 25 pound monkey.

So it would have no trouble hunting humans.
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Mulawin
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08pateldan
Jan 21 2013, 11:08 AM
Roughly how strong were a haast eagles talons?
And apparently I have misunderstood psi strength, what have I misunderstood?

Its about 40% bigger and heavier than the modern largest eagles like Harpy and Philippine eagles with a bigger claws and much heavier, It would probably almost twice stronger and Haast's eagle was also a forest eagle like the Harpy, Philippine and Crowned eagles a type of eagle which are considered more powerful than soaring eagles.

Bite force and grip strength are measured in psi regardless the "specific strength per area" by closing its claws and generate a powerful grip force up to a certain level of strength that had been measured. different eagle specie have different grip strength. A fish eagle has a smaller foot span and talons as compared to forest eagles which prefers to hunt small to medium size mammals and with much stronger grip. for example a Bald eagle is much bigger in size and weight than a Crowned eagle but the crowned eagle has a much bigger foot/talon span and stronger grip, adapted to hunt much larger prey mostly on mammals than the Bald eagle which feed chiefly on fish.


Harpy eagle grips a measuring device.

Although this may not get the accurate true measurement (atleast you can have an idea).
as compared to a lifeless device, a large struggling or fighting back prey would be more fierce and a much stronger grip will be applied by the bird to subdue the prey.


Edited by Mulawin, Jul 11 2013, 11:05 AM.
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Canadianwildlife
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Thats a no brainer question. I believe a crowned eagle could kill a human, if it was by stealth. I don't think a crowned would risk it face to face though.

Now about the haasta eagle.

Haast's eagles preyed on large, flightless bird species, including the moa, which was up to fifteen times the weight of the eagle.[4] It is estimated to have attacked at speeds up to 80 km/h (50 mph),[3] often seizing its prey's pelvis with the talons of one foot and killing with a blow to the head or neck with the other.[citation needed] Its size and weight indicate a bodily striking force equivalent to a cinder block falling from the top of an eight-story building.[16] Its large beak also could be used to rip into the internal organs of its prey and death then would have been caused by blood loss.[citation needed] In the absence of other large predators or scavengers, a Haast's eagle easily could have monopolised a single large kill over a number of days.[1]

This eagle could most certainly kill a human face to face or by stealth. Female birds averaged 31 lbs in weight, with a wingspan of 8 and a half to ten feet long averaging just over 9 feet.

These birds were even said to be man killers when the maori arrived.

In New Zealand, both the fossil record and Maori legend tell us of a giant raptor known as Haast’s Eagle (Harpagomis moorei) that was once the largest predator in New Zealand. The giant Haast’s Eagle, it is believed, attacked and killed the 300-pound moa, a flightless bird reminiscent of an ostrich or emu though much larger, as one of its main food sources. Both the Haast’s eagle and the moa are now extinct. The oral legends of the Maori people, however, recall the Haast’s eagle, called pouakia or kokioi in their language, as a flying beast of fearful hunting prowess, and, if they are to be believed, the giant Haast’s eagle may have been hunting and killing human beings around the same time as Columbus was discovering America.

Slide show: Pictures of Haast's Eagle and the giant moa
Legends say that Haast’s Eagle could and did kill and eat human beings. If it fed on 300-pound moas regularly, then perhaps this legend is not so far-fetched. Most adult humans, especially those with a handy weapon, would have been able to fend off the Haast’s Eagle without too much difficulty, if they saw it coming, even though the Haast’s Eagle was much bigger than even the biggest eagle of today. The forty-pound giant Haast's Eagle swooping down silently from behind and striking at the head and neck of an unaware human, however, would have been an extremely serious, if not fatal, blow.

As Maori legends relate, it is not hard to imagine that a determined raptor as big as the Haast’s Eagle could kill a child of even medium size without too much difficulty. Paul Scofield and Ken Ashwell of the Canterbury Museum of New Zealand and the University of New South Wales, respectively, have recently completed a new study of the Haast’s Eagle in which they used CAT scans to create visual representation of the nervous systems and sensory organs of Haast’s Eagle and compared these to modern raptors in an attempt to learn more about its behavior.

Based on this new research, they concluded that the Haast’s Eagle, the legendary pouakai of the Maori, probably perched high above its hunting grounds searching for prey before swooping down upon them for a killing blow. This matches the Maori legend of the Pouakai swooping down on people and lends some scientific validity to the ancient stories.

The Haast’s Eagle became extinct about 500 years ago, yet such is the power and longevity of the oral record among the Maori people that seemingly accurate accounts about the behaviors of Haast’s Eagle have persisted through the centuries.

Imagine the power of a 40-pound raptor swooping down at speeds of up to 45 miles per hour (assuming a hunting flight speed similar to today’s eagles) and striking out at its prey with powerful, sharp claws, each of which could strike home like a three-inch-long dagger. Killing the 300-pound moa with a single strike to the head or neck, Haast’s Eagle was almost certainly capable of killing human children or even adults.

Haast’s Eagle lived and hunted in New Zealand long before humans began colonizing the island about 750 years ago. It is believed that within a relatively short span of time, human hunting and habitat encroachment, including the burning of large areas of New Zealand’s forests, killed off the Haast’s Eagle, which was by far the largest predator on the island of New Zealand while it lived. The Haast's Eagle's range was sharply reduced almost as soon as the Maori arrived and it may have encountered humans only rarely during its last century.

However, we technically have no proof that they did kill humans, but I believe that they may have. They easily have the capability to. Its common sense, and this question was kind of dumb, no offence ajentjaguar. If they can kill a giant moa weighing 300-to over 600 lbs with feathers to protect them, then they could easily kill a 200 lb or whatever adult human male. And if you ask me, I doubt he would try or have time to even fight back, considering that the eagle is swooping downwards with great force at 45-50 mph. The best thing to do, instead of just run straight like those woman did in that video, would to run sideways or zigzag, taking cover as soon as you can. It would be unwise no matter how strong you are to try and physically defend yourself from and eagle that large and powerful swooping down at 45-60 mph. Plus, if a harpy can produce a 5 inch back talon, imagine how long a haasta eagles talon could be.

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7574
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me thing wedge tail-eagle could do it even adult Red kangaroo 200 lb not save forum sky hunter
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blaze
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Responding to a year old comment.

Quote:
 
Bite force and grip strength are measured in psi regardless the "specific strength per area"


Lots of people do this, I don't know why but is incorrect, it even says so in the name of the unit, psi means pounds per square inch, is a unit of pressure not strength, the correct unit for strength in the imperial system is pounds feet (lbs-ft).

This is an example of why using a pressure unit as if it was an unit of strength is bad.

You have a needle, which has a head 1mm in diameter thus an area of 0.785mm2, if you put a weight of 1 pound on top of it, the pressure exerted at the head of the needle is 1 pound for every 0.785 square millimeters which translates to 82,144 psi
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Ornitholestes
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It could kill a human by ambush, but a healthy man would be able to defend himself.
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Canadianwildlife
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NOTORNIS
is the journal of the Ornithological Society of New Zealand (Inc.)
Editor B. D. Heather,
10 Jocelyn Crescent,
SILVERSTREAM
VOLUME 39 PART 4 DECEMBER 1992
NOTES ON THE WEIGHT, FLYING ABILITY,
HABITAT, AND PREY OF HAAST'S EAGLE
(Harpagornis moorei)
By D. H. BRATHWAITE
INTRODUCTION
Apart from the publications of Haast (1872, 1874, 1881), Owen (1879),
Hamilton (1893,1894), Shufeldt (1896); and Oliver (1930,1945,1955), most
statements on Haast's Eagle have been anecdotal or repetitions of previous
work. Early workers' conclusions, based on examination of specimens, have
often been misquoted, particularly about the length and proportions of the
wing bones, by others who have not seen material themselves. This has led
to the present popular impression that the bird was becoming flightless.
There has been little original work on the species since Oliver examined
the structure of the palate (Oliver 1945).
Most authors who have discussed the eagle have commented on its size,
possible relationships, and habitat (e.g. Duff 1949, Haast 1872, Hamilton
1893, McCulloch 1982). My own interest in the bird was aroused by
discussions at the Ornithological Society's 1975 summer school of ornithology
in Nelson. The suggestion was made that the eagle was as large as the
teratorns of the Californian (Rancho La Brea) tar pits, which were predatory
birds larger than the present-day Californian and Andean Condors (Feduccia
1980).
I set out to calculate the eagle's weight and to see whether there was anything about its proportions or structure which would have prevented its
flying. From the results, I speculated further on its habitat, flight pattern,
and probable prey.
METHODS
I assumed that the weights of birds of different body size are related to the
difference in trunk volume and calculated the body weight by proportion.
This method has been used for estimating body weights of other extinct birds 240 BRATHWAITE NOTORNIS 39
(McNeill Alexander 1983). For Haast's Eagle, I used body dimensions of a mounted skeleton (Otago Museum Cat. no. C40.8) assembled from material
collected at Castle Rocks in western Southland by Augustus Hamilton in
the 1890s (Hamilton 1893, 1894). The trunk volume of this specimen was compared with those of mounted skeletons of the Australian Wedge-tailed
Eagle (Aquila audax) (AV5209) and White-bellied Sea eagle (Haliaeetus
leucogaster) (AVS? 10 - Java) in Canterbury Museum.
I did not use limb bone lengths in weight measurement because no formulae were available when this study was done. Those now available for
the wing are highly dependent on wing proportions. Relationships based on leg bone dimensions have been derived from samples including many
higher taxa (e.g. Prange et al. 1979).
Means and ranges of weights for the two living species were available
from several literature sources. I used those in Brown & Amadon (1968)
and Brown (1976).
The dimensions used were: trunk length (TL), from the anterior of the
furcula bow to the posterior tip of the pygostyle; maximum trunk width
(MTW), measured across the thoracic ribs as mounted; and maximum trunk
depth (MTD).
Dimensions of the Otago Museum skeleton of Haast's Eagle were then
expressed as proportions of the same measurements of mounted skeletons
of the living eagles. From these proportions, the weight of the living Haast's
Eagle was calculated.
I estimated the wing span of the Otago specimen of Haast's Eagle by
first estimating the normal angular relationship between the wing bones in
a spread wing and then drawing a reconstruction of the wings and associated
flight feathers. For the feathered sections, I used standard wing lengths for
large raptors from Brown & Amadon (1968) as a guide. Although some long-
winged birds, such as albatrosses, have short flight feathers, I assumed that
the feather proportions in Haast's Eagle were similar to others in the
Accipitridae. A relatively short ulna is characteristic of broad-winged forms,
such as the large forest eagles, and not of open-country species (pers. obs.).
Tail length was then based on wing proportions, according to possible
aerodynamic requirements for bird tails. The stalling speed of a very heavy,
broad-winged bird tends to be higher than in birds with a high aspect ratio
wing; and a long, broad tail can provide compensatory lift at high angles
of attack and low air speeds (Maynard Smith 1953).
The mounted skeleton of Haast's Eagle in Otago Museum is of a small
individual, smaller than many others represented by fewer elements in various
collections and so it was assumed that it was a male. Females are generally
larger than males in hawks and eagles (Brown & Amadon 1968). A possible
wing configuration for the larger female was obtained by increasing the length
of the major wing bones to the largest known and increasing the feather
outline in linear proportion.
RESULTS
Body Weight
The measurements of the mounted skeletons of the three eagle species are
given in Table 1. The dimensions of the skeleton of Haast's Eagle as 1992 HAAST'S EAGLE 241
TABLE 1 -Trunk measurements of mounted skeletons of Haast's Eagle (Harpagornis
moore0 and two living Australian eagles. TL, trunk length (mm); MTD,
maximum trunk depth (mm); MTW, maximum trunk width (mm).
Species
Harpagornis Haliaeeiw Aquila audax
rnoorei leucogaster Dimension
TL 340 324 270
MTD 135 99 78
MTW 190 144 120
TABLE 2 -Trunk dimensions of mounted skeletons of Haast's Eagle (Harpagornis
moore0 expressed as proportions of the corresponding dimensions of
mounted skeletons of two Australian eagles, and weight of Haast's Eagle
as a proportion of body volume (product of trunk dimensions) of the other
species. Abbreviations as in Table 1.
Species
Dimension
Haliaeetus Aquila
leucomster dm
TL
MTD
MTW
Weight
TABLE 3 - Live weights (g) for Aquila audax and Haliaeetus leucogaster, from
literature sources, as acknowledged. First set for Aquila audax gives
mean, followed by range and number of individuals.
Weight (source)
-
Species Brown & Arnadon (1968) Poole (1938) --
Haliaeetus leucogaster 2475-2800
Aquila audm 3402 (2495-4536; 43) 4664
3346 (mean of 127)
proportions of the correspondmg dimensions of the two living species are
given in Table 2.
Published weights (Table 3) suggested that the Wedge-tailed Eagle
should have been heavier than the sea eagle, but those for the sea eagle were
based on a small sample and it is possible that larger individuals exist. It BRATHWAITE 1992 HAAST'S EAGLE 243
was assumed, therefore, that the sea eagle skeleton was from a very large
female and that the Wedge-tailed Eagle skeleton was from a bird of average
diminsions. Alternatively, the specimen may be misidentified, as are some others in the collections acquired by Canterbury Museum last century (R.N.
Holdaway, pers. comm.) . The Wedge-tailed Eagle was assumed to have weighed 3.346 kg (mean, n= 127, Brown & Amadon 1968). If trunk volume is proportional to live
body weight, the male,Haast's Eagle from Castle Rocks weighed about 11.5
kg in life. Using data for the White-bellied Sea Eagle, the weight of the
Haast's Eagle was 5.26 kg. In view of the doubt about the identification of
the sea eagle, the weight based on the Wedge-tailed Eagle skeleton was accepted.
The longest ulna of Haast's Eagle in Canterbury Museum (AV36405;
279 rnm) was 17% longer than that of the Otago Museum skeleton ((240.8).
Weight is proportional to the cube root of linear dimensions but the square
root of areas. As ulna length is a measure of wing area rather than of body
size, body weight should be proportional to the linear measurement cubed
divided by the measurement squared. Therefore, the female weight was calculated as male weight x 1. 17312, which gave 11.5 x 1.27 = 14.46 kg for
the female.
Wing proportions
Figure 1 shows scale outlines of the Australasian Harrier (Circus approximans),
Haast's eagle, and the Wedge-tailed and Australian Sea Eagles. Both eagles
have been suggested as near relations of Haast's Eagle (Oliver 1930, 1945,
1955, Shufeldt 1896).
The scar of the supracoracoideus muscle was large in comparison with
those for the other two eagles (Figure 2), which suggested that Haast's Eagle
had a more powerful upstroke of the wing. However, I did not have enough
FIGURE 2 - Right lateral views of sterna of: A, Har agornis moorei, lower edge of
keel reconstructed; B Aquila audax; 6 Ha,iaeefus leucogaster. Scar
of supracoracoideus muscle indicated by hatching. Scale bar 100 mm. - TABLE 4 - Weight (W, kg), wing span (span, mm), wing area (area, m2), wing
loading (L, g ~m-~), span loading (SL, g cm-'), and aspect ratios (AR,
span2/area).
- -
Species Sex W Span Area L SL AR
Aquila audax 4.5 2.25 0.573 0.785 20.0 8.84
Haliaeetus le~~cogaster 2.8 2.20 0.643 0.435 12.7 7.54
Circus approximans 0.7 1.23 0.194 0.360 5.68 7.8
Harpagomis ntoorei 3 10.35 2.14 0.821 1.261 48.4 5.58
14.46 2.43 0.959 1.502 59.5 5.66
Wing:tail lengths for large raptors
Comparison of open country and forest species
Key
550 0 Forest species
7 0 Open country species
0 Aquila gurneyi
10
200 J--- -7-- , 300 400 500, 600 700 800 900
Wing length (mm)
FIGURE 3 - Standard wing versus tail measurements for a range of large raptors
from forest and open country habitats. Data from Brown & Amadon
(1968). Where only ranges available, points plotted were largeqt from
overall, or female where differentiated, ranges. Means were used where
given. Species: 1, Spizaetus ornatus; 2, Morphnus guianensis; 3,
Stephanoaetus coronatus; 4, Pithecophaga jefferyi; 5, Aquila gurneyi;
6, Aquila audax; 7, Gypaetus barbatus; 8, Harpia harpyja; 9, Aquila
verreauxi: 10. Aeav~ius monachus: 1 1. Aauila heliaca:12. Aauila raoax: 13, Polemaetus 6iiicosus; 14, ~ahaeetus albicilla; 15, GV~S fulvu& 16,
Aquila chrysaetos; 17, Haliaeetus leucocephalus. Note posltlon of Aquila
gurneyi. 1992 HAAST'S EAGLE 245
data to show whether the scar was proportionateily larger in Haast's Eagle,
and so this is conjectural.
Wing spans, areas, and aspect ratios obtained from the illustrations in
Figure 1 are surnrnarised in Table 4. The span and aspect ratio estimated
for Haast's Eagle were lower than those for the other species, which all inhabit
open country (Brown & Arnadon 1968). Wing and tail lengths for a range
of large raptors from forest and open-country habitats are plotted in Figure 3.
DISCUSSION
The Live weights estimated here for Haast's Eagle, about 11.5 kg for a male
and over 14 kg for the female, make this eagle up to 30% heavier than the
largest living eagle, the South American Harpy (Harpia harpyja) (Brown &
Amadon 1968). Even if the method overestimated the weights by 10%, the
bird would still have been much heavier than the Harpy. This great weight was borne on wings which were proportionately shorter but broader than
open country eagles such as the Australian Wedge-tailed Eagle and the White-
bellied Sea Eagle.
Aerodynamic considerations (Maynard Smith 1953) support the idea that
broad short wings are associated with a comparatively long tail, unlike the
short tails of most open-country eagles. In turn, short, broad wings and long
tails are characteristic of forest eagles (Bmwn 1976 and Figure 3). If Haast's
Eagle had the long tail normally associated with its proportionately (not
absolutely) short wings, it probably inhabited forest.
This is supported by evidence on former vegetation patterns in New
Zealand. It is now generally accepted that New Zealand was mainly forested
before Polynesians arrived about 1000 years ago (McGlone 1988, Molloy
et al. 1963). Sites such as Pyramid Valley, where bones of Haast's Eagle have
been found, were in areas where forest was the dominant vegetation (Molloy
et al. 1963) and the eagles must have been living in forest at those sites.
The only species presently placed either in the genus Aquila or in
Haliaeetus, which normally inhabits forest, is Gurney's eagle (Apila gumy)
of New Guinea (Brown & Amadon 1968). This bird seems to have different
proportions from typical Aquila (Figure 3) and may not belong in that genus
at all (Brown & Arnadon 1968).
The very large bones of Haast's Eagle have led to the notion that the
bird flew poorly and spent much of its time on the ground (e-g. McCulloch
1982, Millener 1984). Indeed, some authors have suggested that it was becoming flightless (Duff 1949). This would be a very surprising evolutionary
path for a large eagle to take, and is not supported by the full development
of the bones of the wing and shoulder girdle. It is also probably based on a misreading of Haast's and Owen's original comments (Haast 1874, Owen
1879) on the proportionately short ulna. This has been, for example in Duff
(1949), translated into a short wing, when both the earlier authors were only
stressing the different proportions and not the absolute length of the wing.
Neither Haast nor Owen doubted that the bird could fly well (Haast 1874,
Owen 1879). While it could certainly fly, its great weight would have causqd some physical and aerodynamic problems for Haast's Eagle. Takeoff should be
the most difficult phase of flight in very large birds (Maynard Smith 1953).
Unlike the very large vultures, large eagles do, not need take-off run (A.
Kemp, in litt.) and rise from a standing start. The African Crowned Eagle
(Stephanoaetus coronatus) can take off almost vertically from the forest floor
(Brown 1982) by jumping into the air and flapping vigorously.
The legs of Haast's Eagle had very large muscles, as shown by the points
of attachment on the leg bones themselves and on the pelvis (pers. obs.).
Strong legs may have allowed the birds to spring into the air, too. If the
supracoracoideus muscle was disproportionately large in Haast's Eagle, as
the large scar on the sternum suggests, the wing upstroke would have been
powered during take-off and initial climb to 3 tree limb.
Very large birds, including forest eagles (Amadon & Brown 1968) fly
infrequently but rapidly. Forest eagles usually watch for prey from pe~ches
in tall trees, and then attack with great speed and agility. The Harpy can manoeuvre through the South American rain forests at 60-80 km h-I (Brown
1976). There are no data on the proportions of red and white muscle fibres
in the pectoral muscles of forest eagles, but it would not be surprising if
there were a high proportion of white fibres. These produce a high power
output for brief periods, in contrast to the red fibres which are used in
sustained, aerobic activity.
The size of Haast's Eagle suggests that it, too, would have flown down
from high perches to attack its prey and that it had reasonably high food
requirements. These points raise the question of its probable prey. Three
groups of large herbivores were present in the Holocene fauna, and all are reasonable candidates: the flightless geese (Cnemiornis), the gruiform adzebills
(Aptomis), and the moas (Dinornithidae and Emeidae). Prey smaller than
the Takahe (Porphyria mantelh) or Kakapo (Strigops habroptiEus) would have
been too difficult to grasp and hold with the huge talons.
Of the likely prey, the geese and moas may have been major items in
the diet. The adzebills, if rarity of remains indicates rarity in life, would
have been too uncommon to have been a staple. However, the eagle should
ha$e had little difficulty in knocking down and killing a goose or a moa,
particularly the smaller species such as Anomalopteryx didifi, Megalapteryx
didinus, and Eutyaptetyx geranoides.
Larger prey, such as Pachyomis elephantopw or the species of Dinornis,
would not have been out of the question, however, because the African
Crowned and Martial Eagles kill antelopes several times their own weight,
up to 5 times its body weight for the Crowned Eagle (Brown 1982). That
such a large and powerful predator as Haast's Eagle, equipped with enormous talons, could take birds weighing up to 200 kg is not impossible when an eagle tackling an antelope has to deal with a four-legged animal capable of
maintaining its balance and running off into dense vegetation. A goose or a moa could have been knocked off its feet by a high-speed strike from the
heavy predator, and then killed by repeated grips with the talons.

http://notornis.osnz.org.nz/system/files/Notornis_39_4_239.pdf

So in conclusion, the best estimate was that the female haasta eagle averaged 31 lbs in weight with a wingspan of 8 and a half feet to ten feet, averaging about 9 to 9 and a half feet, and with an average body length of 4 and a half feet. Exceptionally large females probably approached 40 lbs in weight.
Edited by Canadianwildlife, Jul 16 2014, 06:05 PM.
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