Talk:Steller's sea eagle
|This is the talk page for discussing improvements to the Steller's sea eagle article.
This is not a forum for general discussion of the article's subject.
|WikiProject China||(Rated C-class, Low-importance)|
In build section: Gender should probably be genus
There seems to be some other odd bits of prose in the article: Habitation level of a Steller's sea-eagle is local than it of a White-tailed Eagle of relation class. I suspect machine translation. - Smerdis of Tlön 19:48, 2 October 2006 (UTC)
It says that the Steller's Eagle is the heaviest eagle in average with 6.8 kg, but the Philipines Eagle weights in average 7kg, and the Harpy Eagle, 7.5kg. In fact one Harpy Eagle reached 12.3kg 188.8.131.52 15:36, 6 October 2007 (UTC)
That is not the average weight 6.8 kg, It's the start of the average measurements which is 6.8 kg to 9 kg that is why ON Average, The Steller's sea eagle is the heaviest eagle in the world.
DESCRIPTION:(as written in the Information) "The typical size range is 86.5-105 cm (34-41 inches) long and the wingspan is 203-241 cm (6.8-8 feet). On average, females weigh from 6.8 to 9 kg (15 to 20 lb), while males are considerably lighter with a weight range from 4.9 to 6 kg (10.8 to 13.2 lb)."
Of the three species the emphasis in weight always referring to the female eagle species because it's larger than males.
Philippine eagle averaging 5 kg to 7 kg; while Harpy eagle average weight is 4 kg to 7.5 kg and the one who reached 12.3 kg is a captive bird named "jezebel" as stated in the Harpy eagle's information. An "exceptional" individual bird which cannot represent the true weight of the specie. —Preceding unsigned comment added by 184.108.40.206 (talk) 13:11, 16 October 2007 (UTC)
Well I just got that data from wikipedia itself. After a little more resaerch I found this:
All of these sites have different average weights for the Harpy Eagle, much larger than 4 - 7 kg. By these sites, Harpy Eagle weights, in average 6.5 - 9 kg (14 to 20 lb), and one of them, specifically says that female has an average weight of 8.2 kg. That is about the same average weight you said about the Steller's Eagle.
This other site gives the Steller's Eagle 6 - 9 kg:
I havent done further research on the Phillipine Eagle, but I think it is about the same average weight.
Other sites I have researched:
Considers Steller's Eagle the third largest eagle of the world
Gives Steller's Eagle 9 kg maximum
Calls the Steller's Eagle the heaviest eagle in the world, but gives it 6.8 - 9 kg
- http:// identify.whatbird.com/obj/435/_/target.aspx
I believe this site was the source of confusion. I will just quote it:
"They are the heaviest eagle in the world, averaging about 15 lb, but they lag behind the Harpy and the Philippine Eagle in other measurements. An unverified record exists of a huge female, gorged on salmon, weighing 28 lb."
The site says the average weight of the Steller's Eagle is 15 lb, or 6.8 kg. This wouldnt make it the heaviest eagle, but, still, the site gives it this title.
220.127.116.11 01:09, 23 October 2007 (UTC)
And by the way, Steller's Eagle has a larger wingspan than the Harpy: 240 cm maximum, to 200 cm maximum 18.104.22.168 01:13, 23 October 2007 (UTC)
Source of confusion:
The site (Wikipedia) says the average weight of the Steller's sea eagle is 15-20 lb or 6.8 to 9 kg. This on average it's the heaviest eagle in the world beating the Harpy eagle which weighs 4.75 to 7.5 kg on average; while the Philippine eagle weighs 5 to 7 kg on average.
The Steller's sea eagle is a fish eagle, (the BIGGEST bird in the Genus Haliaeetus) and is one of the largest raptors overall; The Steller's is shorter in length but longer in wingspan as compared to forests eagles like the Philippine eagle and the Harpy eagle which has longer tails but shorter rounded wingspan in relation to their size, An adaptation for quick controlled flight maneuvering in dense foliage and I think the legs and talons of the Steller's eagle are also smaller which where it lag behind with the two forest eagles.
I think the source of confusion started at the "average weight of 6.8 or 15 lb" which should've been written as 6.8 - 9 kg (15-20 lb) average.
If you will get the 6.8 as the average for the Steller's eagle then the Harpy eagle will only average 4.75 kg and the Philippine eagle will weigh only 5 kg on average, because 6.8 kg is the start of the measurements; which is 6.8 - 9 kg as stated in the "description" of the Steller's sea eagle information. —Preceding unsigned comment added by 22.214.171.124 (talk) 05:53, 23 October 2007 (UTC)
The Harpy Eagle doesnt average 4.75 - 7.5 kg, but 6.5 - 9 kg, the same of the Steller's Sea Eagle. Your information is wrong. Check those sites. 126.96.36.199 15:56, 23 October 2007 (UTC)
BTW we are talking about Wikipedia's information alone, It has nothing to do with the other sites. Harpy eagle average wieght 4.75 to 7.5 kg on Wikipedia.
And please don't try to change the Harpy eagle's average weight information on Wikipedia, (6.5 - 9 kg) 6.5 is very unrealistic for a male Harpy eagles which could only possibly weight 5 kg max in the wild.
If Wikipedia is incorrect, then we must correct it. Female Harpy Eagle's weight is 6.5 - 9 kg, AND THAT WAS IN THE ARTICLE, males weight around 3.8 - 5.4 kg.
You are trying all you can to make Steller´s Eagle the largest eagle aren't you??
188.8.131.52 16:09, 24 October 2007 (UTC)
BTW you dont have authority to delete references and external links that are pertinent to the subject
184.108.40.206 16:18, 24 October 2007 (UTC)
- Please don't assert anything about other users' authority - anyone can edit the encyclopedia, and hopefully consensus will be attained by collaboration. Also I'd encourage all of you who are editing anonymously to register so that there can be more continuity to this conversation. de Bivort 19:11, 24 October 2007 (UTC)
- Well, Im the 189 and the 201. Here I am, waiting for some other action than just erasing what Ive done. Vermelhored 20:10, 24 October 2007 (UTC)
You still didn't get my point?
Nobody is asserting authority or prohibiting you from correcting informations here; This is how Wikipedia grows or expands its compilations of information. Anyone, anywhere and anytime in the world can contribute, edit the informations.
Nope, I was not trying to make Steller's sea eagle to be the largest eagle in the world, because that tittle belongs to the Philippine eagle - the largest living eagle species. I was merely explaining (the confusions of information), elaborating the facts regarding the informations WRITTEN here (Wikipedia), no more, no less.(prior to our discussion; before you edited the weight of the Harpy eagle 4.75-7.5 kg) I dont have business knowing what ever the measurements you've got in the other sites. (This will be my last post)
The Largest Eagle in the world. http://www.haribon.org.ph/?q=node/view/117 http://animaldiversity.ummz.umich.edu/site/accounts/information/Pithecophaga_jefferyi.html http://www.thebeckoning.com/explorations/world/brazil/brazil2006-day10.html —Preceding unsigned comment added by 220.127.116.11 (talk) 07:25, 25 October 2007 (UTC)
"“The term largest can have different meanings,” he said while pulling out and handling the specimens one by one like a delicate baby. “The Harpy Eagle maybe the largest in terms of bulk or weight, but the Philippine Eagle is the largest in terms of wingspan and height.” There you go—confirmation from no less than Dr. Kennedy!"
taken from your first site, haribon.org. The Harpy is the bulkiest, the Phillipine, the tallest and the Steller's, the one with the laregst wingspan. 18.104.22.168 15:58, 25 October 2007 (UTC)
To be fair you should have also quoted the conclusion and not just taking words out of contex. - Haribon.org (The largest eagle in the world)
CONCLUSION: "The Haring Ibon tops in 5 of the 7 external measurements, namely, total length, bill gape, culmen, bill height and tarsus. The Harpy tops in 1 out of 7 measurements, namely the talon. In the wing measurement or wing chord, Haring Ibon is only second but Harpy Eagle is fifth."
"Well, this is just a simple exercise to illustrate that we now have a basis for proclaiming that “Haring Ibon or the Philippine Eagle is the largest eagle in the world.”
The Harpy Eagle is the “heaviest eagle in the world,” at least one book says so (i.e. Cambridge Encyclopedia of Ornithology (1991)). But we have nothing on hand in terms of data. —Preceding unsigned comment added by Inputlogs (talk • contribs) 05:14, 1 November 2007 (UTC)
Size comparison based on data by Ferguson-Lees et al.
From Raptors of the World (Ferguson-Lees et al. 2001), something of a raptor bible:
- Steller's Sea Eagle length 85–105 cm; wingspan 195–230 cm (wing length 610–620 mm female, 570–590 mm male); weight 6.8–9.0 kg female, 4.9–6.0 kg male. BirdLife International entry
- Harpy Eagle length 89–102 cm; wingspan 176–201 cm (wing length 583–626 mm female, 543–580 mm male); weight 6.0–9.0 kg female, 4.0–4.8 kg male.
- Philippine Eagle length 90–100 cm; wingspan 184–202 cm (wing length 574–612 mm); weight 4.7–8 kg. BirdLife International entry
So, while Steller's Sea Eagle and Harpy Eagle equal in maximum weight, Steller's is heavier on average, especially if you take both sexes into account. Note that Steller's is largest also based on maximum length and wingspan, contrary to the article's incorrect statements. Another book on eagles had the Steller's Sea Eagle's maximum weight at 8.97 kg, and 9.0 kg is likely rounded from that. The Philippine Eagle is clearly smaller than the other two, although it deserves to be mentioned, as these species comprise the "big three" of eagles, with no other species exceeding 7 kg (although there is a weight of 7.5 kg for the White-tailed Eagle in older Russian literature, but most authors settle for 6.9 kg as maximum; the largest subspecies of Golden Eagle (A. c. daphanea) is another possible exception, as there is little data for it).
Note that none of these is the largest eagle based on wingspan, but are eclipsed by White-tailed Eagle (193–244 cm), Golden Eagle (180–234 cm) and Wedge-tailed Eagle (182–232 cm). One has to be extra cautious with wingspan data, as older literature is embroidered with inaccuracies: I've seen 280 cm for Steller's and 240 cm for Harpy, for example. Indeed, some books have noted that Steller's is relatively short-winged for a sea eagle. Although with its wide paddle-shaped wings it's still likely to have the largest wing area of all eagles.
The Stellar doesnt have largest wing surface area; that belongs to the phillipine eagle which can reach upto 4.3 ft in length. The second longest is the wedge tailed at 4 ft in length. Then its the steller's sea eagle, harpy eagle and the largest species of golden eagle. Heaviest eagle ever from each subspecies: Stellar's Sea Eagle - 28 lbs, Harpy - 26 lbs, Philippine - 22 lbs, Golden - 20 lbs and Wedge Tailed - 16 lbs. The Golden eagle should be considered smaller then the rest because it doesnt top in anything except for the fact that it can kill a wolf as proven in mongolia's wolf hunts. It is far smaller in all of the measurments then the other eagles. Steller Sea Eagle has a max wingspan of 250cm compared to the 200 cm for philippine and harpy eagles. The Harpy Eagle is just considered largest because of one measurement that it excels in the claw length so therefore Philippine is largest.
I think your source of information needs to be updated (James Ferguson etal, 2001)
These are the most recent data available: (2006-present)Check them out!
The Largest Eagle in the world. http://www.haribon.org.ph/?q=node/view/117 http://animaldiversity.ummz.umich.edu/site/accounts/information/Pithecophaga_jefferyi.html http://www.thebeckoning.com/explorations/world/brazil/brazil2006-day10.html http://ngm.nationalgeographic.com/2008/02/philippine-eagles/mel-white-text
The Haribon.org has a supporting data (actual data measurements of specimen)of which shows the Harpy eagle doesn't even reached 100 cm on average and it seems male Philippine eagles (some are even Immature) are even longer than the female Harpy eagles.
The Philippine eagle TOPs 5 out of 7 measurements Namely the total lenght, Tarsus, Bill height, bill culmen and bill gape.In wing cord Haribon is second to Golden eagle but the Harpy is only 5th. Harpy ragle tops one category longest hind talons. Philippine eagle has the largest wing surface area though they're not the longest wingspan since it's a forest eagle like the Harpagornis an adaptation for quick turns and maneuverability when hunting in dense forest. See those broad wings?...you don't even have to measure them; COMPARE them to the wings of Golden eagle, White tailed eagle, Steller's sea eagle, etc. http://youtube.com/watch?v=1K_G6xQGduw
The Philippine eagle like the Harpagornis is the TOP predator of the ecosystem they live in, with no competition from other large predators like big cats or bears they have the Philippine islands all to themselves and they evolved/grew BIG. Source:http://ngm.nationalgeographic.com/2008/02/philippine-eagles/mel-white-text —Preceding unsigned comment added by Informaticz (talk • contribs) 08:02, 25 February 2008 (UTC)
- I think I'll refrain to a literary source backed up by 18 years of research, rather than obscure web articles containing less text than the book's bibliography section. Admitted, National Geographic is hardly obscure, and some of the other links are pretty good too – that haribon.org even has believable hindclaw measurements (I've seen absurd 12–13 cm claims for the Harpy). However, none of them offers contrary information on weight, and weight – not bill (this probably goes to Steller's  anyway) or tarsus length – is the issue here, so let us not get sidetracked. And based on average weight the ranking is clear: 1. Steller's, 2. Harpy, 3. Philippine – the only debatable aspect is that based on maximum weight it could be called a tie between Steller's and Harpy. Also, data should be collected from live or recently dead birds, while using museum samples is discouraged. Haribon.org also fails to make comparisons with the Steller's – the true champ – and any data including a comment like "Based on a very limited available number of specimens and selected external measurements..." can hardly be taken as conclusive.
- The Philippine does indeed appear to have a larger wingspan than the Harpy, and possibly length too; but like said, that's besides the point: otherwise the Wandering Albatross or the Reeves's Pheasant would be considered larger than the Kori Bustard – and in that case neither of the two would be the largest eagle. The Philippine Eagle's claim for the largest wing area among eagles is perhaps correct. Ferguson-Lees has an illustration of flying raptors shown to scale, with following image measurements (taken by ruler): Philippine 50 mm span/12 mm width, Harpy 48/12 mm, Steller's 56/11 mm. Scaled to maximum spans, the real-life widths should roughly be: Philippine 48 cm (span 202 cm), Harpy 50 cm (201 cm), Steller's 45 cm (230 cm). Rough math would suggest (again) the Steller's as largest, but the differences are to small for making such assumptions. The same plate has the Andean Condor's dimensions at 74/15 mm, suggesting a real-life width of 63 cm with maximum span (310 cm). The Condor's maximum wing area, the largest among extant bird species, is probably about 17,000 cm² (based on comparison with measurements taken from California Condors), so the three eagles are perhaps in the region of 8,000–10,000 cm². Here's a picture of a dead Harpy Eagle giving a good idea of the size of its wings.
- I've noticed that articles, documentaries etc. of any of these three often promote their subject as the largest. Science should never resort to picking favourites.
- Thank you for the video. Certainly a magnificent creature, largest eagle or not. And such a rare bird too, making the footage all the more precious.
These are acoording to you/your research findings; "quote" ("The Philippine does indeed appear to have a larger wingspan than the Harpy, and possibly length too; The Philippine Eagle's claim for the largest wing area among eagles is perhaps correct. Ferguson-Lees has an illustration of flying raptors shown to scale, And based on average weight the ranking is clear: 1. Steller's, 2. Harpy, 3. Philippine – the only debatable aspect is that based on maximum weight it could be called a tie between Steller's and Harpy.)Actually most of the link that I've searched and foud out that there is no real agreement of which eagle is the largest in the world; These three species were considered contenders for the largest living eagle species in the world.  
by: Jonathan Wright RE:The Largest eagle in the world.'Quote'("To be honest, I'm only convinced about the first two - the harpy and Philippine eagles. The following eagles could replace any or all of the eagles in places 3-5: Kenyan eagle, martial eagle, American bald eagle, wedge-tailed eagle and verreaux's eagle. I'm sorry for the confusion, but this was a very controversial question.")unquote"
- This "controversy" isn't among well-informed people, as evidenced by the above links and quotations – not to mention the omission of Steller's Sea Eagle altogether, or the inclusion of much smaller species: the "Kenyan Eagle" (Crowned Eagle) has a weight range of 2.7–4.7 kg (about 11th largest) and wingspan of only 151–181 cm for crying out loud! If it's of any help, I can provide the ranking down to it; you know the source.
- 1. Steller's Sea Eagle 4.9–9.0 kg
- 2. Harpy Eagle 4.0–9.0 kg
- 3. Philippine Eagle 4.7–8 kg
- 4. White-tailed Eagle 3.1–6.9 kg
- 5. Golden Eagle 2.8–6.7 kg (possibly excluding max for daphanea)
- 6. Bald Eagle 2.5–6.3 kg
- 7. Verreaux's Eagle 3.0–5.8 kg
- 8. Martial Eagle 3.01–5.66 kg (6.2 kg in captivity)
- 9. Wedge-tailed Eagle 2.03–5.3 kg
- 10. Steppe Eagle 2.0–4.9 kg
- 11. Crowned Eagle 2.7–4.7 kg
- 12. Imperial Eagle 2.45–4.53 kg (inc. adalberti 2.5–3.5 kg)
- This is based on maximum weight, the order may change slightly using averages (the Imperial is included since it may affect this order). I don't have true averages for all, but you should get an approximation by calculating the geometric mean for each range.
- I accept the possibility that there is valid data outside these ranges, but so far almost all reports of greater weights I've seen come from too obscure sources to be taken seriously, and they are few. One exception is 7.5 kg for the White-tailed according to The Birds of the Western Palearctic, Volume 2 Hawks to Bustards (Cramp & Simmons 1980). I also find the range of 3.8–5.4 kg for the male Harpy perfectly acceptable compared to 4.0–4.8 kg by Ferguson-Lees et al.
 I know that in Zoology the weight is the basis or factor in considering the largest species or specimen and in many links the Steller's sea eagle is probably the clear winner; as they claimed some could even reach 28 lbs. 15-20 lb on average followed by Harpy Eagle and Philippine Eagle but in Physical dimensions the Philippine eagle is the largest among the three, Its taller coz' it has the longest tarsus or legs averaging 145-150 mm compare to Harpy's 121-125 mm, as you have said It has the largest in wing surface area, longest body measurement 95-112 cm. and according to the links that I have posted before;
It doesn't really matter of which eagle is the largest, I love birds of prey and I think they are all magnificent and unique, truly special species that evolved and adapted so well to the environment they live in; what is important is how we could save them from extinction for the next generation to also enjoy these amazing creatures.
- I'm not disputing haribon.org's results outright, but I am very cautios, as the data conflicts with previously published material (especially for the "Kenyan Eagle") and it was based on three museum specimens 45 to 52 years old. At least wingspans obtained this way tend to be erroneus, that much I know, and of the measurements at hand wing chords and lengths possibly too, though perhaps not by a significant margin. Could it really be longer than Griffon Vulture (93–110 cm)? In other words: without supporting data these results can't be treated as conclusive.
- Though I'll admit three three things right away:
- 1. Wouldn't be the first time earlier data proves out to be incorrect.
- 2. With such a rare animal on how large a sample could the earlier data have been based on?
- 3. I never meant my earlier speculation of wing areas to be taken as fact, that should have been obvious without saying.
- I don't have a favourite here either, but I do like to get my facts right. Though debating the largest eagle is something of a fool's errand, as taxonomically there's no such group of birds. And the debate was a bit odd to begin with, as weight data found for these three species throughout the web is fairly consistent, and the size ranking really isn't in question. Of course all three have an overlapping range of 4.9–8 kg, so if you were handed a random specimen of each species, any one of them could be the largest; and the size difference is likely impossible to determine in the field. And that's were statistics come along.
The CRC Handbook of Avian Body Masses (Second Edition) gives pretty much detailed datas of raptors weights (ranges, averages, both for males and females, etc...). Unfortunately a friend of mine borrowed it from me, so i cant look up for the biggest eagles, but I think its available on amazon.com, and you can search inside the book. —Preceding unsigned comment added by Nzoltan1981 (talk • contribs) 09:09, 25 March 2008 (UTC)
I never grasped that this controversy existed prior to doing some searches on the largest living eagle in the world. Here is what I have learned from my subsequent research:
- There are only three contenders for largest eagle; Stellers Sea Eagle, Harpy Eagle and Phillipine Eagle
- The reason there are only three contenders is primarily based on weight. No other eagle is close to these three in that category...as opposed to wingspan for instance where it appears the White Tailed Eagle has the greatest wingspan of any eagle including these three. However, because this bird is quite slender and does not weigh nearly what the other three do, it is seldom mentioned nor should it be.
- The three most common measures of raptor size are weight, wing span and length. Most other measures would make for good trivia but be of little value in determining the largest eagle.
- Although it seems to have gained a lot of traction, the study mentioned in this site (and others) by the Haribon association is so biased that it is practically useless. It is clearly evident, they want the Phillipine Eagle to be the biggest. They have doctored their results in two obvious ways and one more subtle way to achieve their end.
- First, (as mentioned above) they do not include the Steller's Sea Eagle in their study and instead include some much smaller eagles that should not even be in the conversation. They are helping their case immensely by eliminating a bird that would win most of their categories. For instance, three of their seven categories relate to the size of the bill. No other raptor bill matches the size (bill height, bill gape or bill culmen)of the Stellers Sea Eagle. Using their own categories, I speculate that the Stellers Sea Eagle would win 4 categories (all three relating to bill, very easily the wing cord and finally, the tarsus) tie 1 category (length) and lose one category (longest hind talon).
- Second, they handpick the categories that the Phillipine Eagle can beat the Harpy Eagle in (which is really what they are trying to get at with this study). The Harpy is the same length as the Phillipine but it weighs 13% more. It is a stockier, more muscular bird. It stands to reason that from talon to neck, all thickness measurements would be greater in the Harpy and you can readily see this in photographs. Any measurements related to talon girth, tarsus girth (seriously...take a look at the girth of the the Harpy tarsus...no other raptor is close on this one), and girth/muscularity throughout the entire torso. The Harpy would win all categories in this arena and I speculate these facts are the primary reason several sites list the Harpy as the most powerful raptor in the world. Instead, the Haribon group chose to concentrate on the Bill, where admitedly, the Harpy has an evolutionarily adapted significantly smaller bill than the other two contenders.
- Third, picking one or two long dead birds as a representative sample needs no further discussion for its lack of statistical credibility.
- Now, back to which of the three is biggest. In an attempt to bring as little bias as possible to the discussion, I will utilize what appears to be the closest thing to an ultimate authority (Raptors of the World by Ferguson-Lees and Christie) for a comparison between adult females for each eagle in the primary size categories (weight, wingspan and length). I will score a 1.0 for a win, 2.0 for second and 3.0 for third (low score wins). The weight of the three for a fully grown female is 9.0 kg (1.0 score), 9.0 kg (1.0 score) and 8.0 kg (3.0 score) for the Harpy, Stellers and Phillipine respectively. The Wingspan of the three is 74" (3.0 score), 84" (1.0 score) and 76" (2.0 score) for the three respectively. The length for the three is 38" (1.0 score), 37" (2.0 score) and 37" (2.0 score) respectively. The Stellers is the biggest eagle with a score of 4.0. The Harpy is the second biggest eagle with a score of 5.0. The Phillipine wins no categories and scores 7.0. Crude I will admit but instructive. I tried a few more intricate mathematical calculations and the overall ranking came out the same each time.
- All this being said, I really do not care which is the biggest eagle, as it appears the Haribon organization does. All three are magnificent, gorgeous raptors and I hope all three survive the ravages of the human race. In that light, all this speculation would be unnecessary if man had not killed off the Haasts Eagle 900 years ago. Were it still living, there would be no debate at all. —Preceding unsigned comment added by 22.214.171.124 (talk) 06:08, 4 July 2009 (UTC)
Hi i posted a link to a website from Klaus Nigge who made some really impressive pictures of steller's sea eagle. Why was the link deleted? i understand that the links shouldn't be used for every website containing some pictures. but these are really world class. can someone explain why the link isn't suitable for wikipedia?
Here is the External Link:
http://nigge.com/projects/stellers_sea_eagle/thumbnails.html —Preceding unsigned comment added by 126.96.36.199 (talk) 21:13, 12 October 2010 (UTC)
Weak Talons and/or feet?
I see many unsourced claims on the internet that the Steller's Sea Eagle has relatively weak feet compared to other large eagles. I am not aware of any scientific or academic support for this. Also, in the Guinness Book of Animal Facts and Feats, they claim that Steller's might be capable of the greatest carrying capacity of any bird, since they can fly with 9 kg zone seal pups. The same book also claims that the Bald Eagle (with a 6.8 kg deer fawn) and White-tailed Eagle (with a 4-year-old girl) are also capable of great feats of flying with heavy potential prey. I suspect that because fish eagles are often scavengers and not as active predators as Harpy or Golden Eagles, people are assuming they are considerably weaker. Is there any scientific proof to contradict this that any knows of?
This is just me going from my gut, but I think fish-eating raptors actually have to have STRONGER feet than their land-hunting counterparts. That's because they catch their prey in the water, ergo, they cannot eat it "on the spot", the way raptors that prey on land animals can. So fish eagles and ospreys have to be strong enough to carry large fish to a perch where they can eat them. In general people tend to underestimate fish-eating animals as being weak, but it takes a lot of strength to fly off with a fish that weighs almost as much as yourself!