BRONTORNIS vs Alaskan Peninsula Grizzly.

[Deleted]

What is the largest bear a brontornis can kill?

[King Kodiak]

Apr 16, 2019 9:20:43 GMT -5 @londonbluebear said:

What is the largest bear a brontornis can kill?

Well according to wiki, this was the third heaviest bird ever, with an estimated weight between 770-880 lbs. so this was a very large predatory bird that attacked by ambush and also by chasing the prey down. According to wiki, this bird was even able to kill Astrapotherium, which weighted nearly 2200 lbs. so it sounds to me like this bird would probably be able to kill any extant bear if its by ambush. Face to face, probably a bear up to the same weight.

[OldGreenGrolar]

Good analysis. The brontornis deserves more credit than its getting. This bird being predatory would also be more inclined to fight rather than run and can use its height and feet to its advantage probably.

[King Kodiak]

This from wiki. Yes i agree, also this bird was very slow so most likely it did not use the runaway technique.

Due to its bulk, it probably had a lifestyle between an ambush predator and one that actively chased prey, pouncing on the latter from a hideout and bringing it down by sheer force of attack after a short chase. In attacking prey (but probably not necessarily in a defensive situation, as it was too slow-moving)

[brobear]

Giant flightless bird vs big male grizzly. 

[King Kodiak]

BRONTORNIS




Brontornis is an extinct genus of giant flightless terror birds that lived in Patagonia, Argentina. The only species currently accepted as valid is B. burmeisteri. It has traditionally been placed in the family Phorusrhacidae, nicknamed "terror birds" for their large size and predatory lifestyle, more specifically the subfamily Brontornithinae, which contains the extremely large and heavy-set phorusrhacids. Fossils of the terror bird have been found in the Santa Cruz and Monte León Formationsin Argentina.

t is known from bones, mainly of the legs and feet but also portions of some skulls and backbone, found in several localities of Santa Cruz Province.

B. burmeisteri was the second-tallest species of phorusrhacid, with a height of around 2.8 m (9.2 ft) and the heaviest species of phorusrhacid with an estimated weight of 350–400 kg (770–880 lb) (Alvarenga & Höfling, 2003), making it the third-heaviest bird ever according to current knowledge (after Vorombe titan and Dromornis stirtoni), and the most massive land predator of its time and place. Due to its bulk, it probably had a lifestyle between an ambush predator and one that actively chased prey, pouncing on the latter from a hideout and bringing it down by sheer force of attack after a short chase. In attacking prey (but probably not necessarily in a defensive situation, as it was too slow-moving) it most likely was the dominant carnivore of MiocenePatagonia, being able to kill even large animals such as the elephant-like Astrapotherium and in the predatory role being on par with a pack of Thylacosmilus (metatherian sabre-tooth). It coexisted with some slightly smaller and more active phorusrhacids like Phorusrhacos, but apparently became extinct before the appearance of the immense Argentavis, the largest flying bird ever.

en.m.wikipedia.org/wiki/Brontornis

[King Kodiak]

It appears Brontornis used to kill Astrapotherium, which weighted up to 2200 lbs, by ambush, so this terror bird would be able to kill the Alaska Peninsula grizzly by ambush. On a strictly face to face fight, at same weight, i believe it should be 50%. 

[brobear]

The giant bird has two weapons ( both quite deadly ): his powerful beak ( probably razor-sharp ) and the talons on his powerful legs. The grizzly's only chance is to get in and fight at close quarters where his grappling ability will pay off. This would be similar to "T-rex vs giant bear".

[King Kodiak]

Ok so out of 10 face to face fights, whats your opinion?

[brobear]

In the early years, if thrown together somehow, the big bird would be a mystery to the bear. The bird would win better than 50%. However, after some time, the grizzly would gain insight on the bird's behavior and fighting style. Then, the bear would learn and adjust his own fighting techniques to defeat the giant bird more often than not - imo.

[King Kodiak]

Terror Birds: Predators With a Kung Fu Kick?

John Pickrell
for National Geographic News
August 1, 2005

Phorusrhacids would give even Alfred Hitchcock the shivers: Also known as terror birds, some were nearly 10 feet (3 meters) tall, weighed over half a ton (500 kilograms), and could swallow a dog in a single gulp.

A new study suggests the extinct predators may have been as fleet-footed as modern cheetahs and that some species may have kicked the bones of their prey kung-fu-style to obtain marrow.

The study is one of the first to shed light on the hunting behavior of these huge, flightless predators, which dominated South America from about 65 million to 2.5 million years ago.

Dog Swallower

"Imagine an ostrich with larger, more powerful legs and neck, armed with massive claws," said Herculano Alvarenga, a terror-bird expert at the Museu de História Natural in Sao Paolo, Brazil.

"An ostrich, the largest living bird, can swallow an apple. But a phorusrhacid could swallow a medium-sized dog in one gulp," Alvarenga said.

s8int.com/phile/mega11.html

[OldGreenGrolar]

I think the brontornis possess the tools to kill an Alaskan Peninsula grizzly bear both face to face and ambush. It has a really strong beak and its feet can do great damage. The bear's best advantage will be a close quarter combat style. This is not going to be an easy win for either face to face.

[brobear]

I'm pretty sure that these big flightless predatory birds were extinct by the late Pleistocene when the black bear, followed by the grizzly, arrived into N. America. They never met. Let/s check: www.prehistoric-wildlife.com/species/b/brontornis.html 
 
Name: Brontornis (Thunder bird).
Phonetic: Bron-tor-niss.
Named By: Francisco P. Moreno & Alcides Mercerat - 1891.
Synonyms: Brontornis platyonyx, Rostrornis floweri.
Classification: Chordata, Aves, Cariamae, Phorusrhacidae, Brontornithinae.
Species: B. burmeisteri (type).
Diet: Carnivore.
Size: Up to 2.8 metres tall.
Known locations: Argentina, Santa Cruz Province.
Time period: Miocene.
Fossil representation: Several specimens, usually of the legs and feet, but some vertebrae and skull material are also known.

Brontornis was easily one of the largest of the known South American ‘terror birds’, and as a member of the Brontornithinae it is noted as being one of the most robust in build. Whereas some terror birds could use their speed to run down prey, Brontornis would have been more suited to ambush tactics against larger prey. This would mean staying amongst trees and tall vegetation to hide its profile while prey wandered close enough for a strike.
The heavy build of Brontornis would have been key to its hunting strategy, essentially relying upon brute force to bring its prey down. One reason for this is that without speed to keep pace with its prey it would need to take it down quick before the prey had time to escape. Another is that as a larger bird it would need to eat larger and more powerful prey items to have enough food to survive. This meant a focus upon prey that could have withstood weaker blows necessitating the requirement for the ability to inflict stronger impacts.
Brontornis placement within the Phorusrhacidae has been questioned on the grounds of its similarities with anseriform birds, more specifically like the large flightless birds of Australia such as Dromornis and Bullockornis. However this similarity may actually be a simple case of convergent evolution as studies of the vertebra have since suggested that Brontornis is indeed more like the other phorusrhacids. This also helps to tie in South America’s geographic isolation from the rest of the world during the Miocene.

Further reading
- Catalogue des Oiseaux Fossiles de la Republique Argentine conserves au Musee de la Plata. - Anales del Museo de la Plata 1:1-71 - F. P. Moreno & A. Mercerat - 1891.
- Systematic revision of the Phorusrhacidae (Aves: Ralliformes) - Papéis Avulsos de Zoologia 43 (4): 55–91 - H. M. F. Alvarenga & e. Höfling - 2003.
- Brontornis burmeisteri Moreno & Mercerat, un Anseriformes (Aves) gigante del Mioceno Medio de Patagonia, Argentina. - Revista del Museo Argentino de Ciencias Naturales, n.s. 9, 15-25 - F. Agnolin - 2007. 
 
                     
 
              

[King Kodiak]

I'm pretty sure that these big flightless predatory birds were extinct by the late Pleistocene when the black bear, followed by the grizzly, arrived into N. America. They never met. 

Brontornis was only found in Argentina, South America. And i believe that it was already extinct when Angustidens appeared. Brontornis lived from the early to mid Miocene, while Angustidens lived from the early Pleistocene to the early Holocene. The Spectacled bear appeared in the late Pleistocene.

[brobear]

Mar 3, 2020 22:34:37 GMT -5 King Kodiak said:

I'm pretty sure that these big flightless predatory birds were extinct by the late Pleistocene when the black bear, followed by the grizzly, arrived into N. America. They never met. 

Brontornis was only found in Argentina, South America. And i believe that it was already extinct when Angustidens appeared. Brontornis lived from the early to mid Miocene, while Angustidens lived from the early Pleistocene to the early Holocene. The Spectacled bear appeared in the late Pleistocene.

Yes, you are right. There were some similar big flightless predatory birds in N. America before the arrival of black bears and grizzlies. Don't know why the "Deleted Member" chose a bird that never lived in N. America. 

[King Kodiak]

Don't know why the "Deleted Member" chose a bird that never lived in N. America

Well he just asked hypothetically, what is the largest bear a Brontornis would be able to kill.

[brobear]

Mar 4, 2020 5:57:59 GMT -5 King Kodiak said:

Don't know why the "Deleted Member" chose a bird that never lived in N. America

Well he just asked hypothetically, what is the largest bear a Brontornis would be able to kill.

Understood. The biggest N. American flightless bird was Titanis walleri which weighed from 300 to 400 pounds. Anyways, my nickel would be on the grizzly. 

[OldGreenGrolar]

The Titanis is not as heavily built as the brontornis.

[tom]

Mar 4, 2020 5:57:59 GMT -5 King Kodiak said:

Don't know why the "Deleted Member" chose a bird that never lived in N. America

Well he just asked hypothetically, what is the largest bear a Brontornis would be able to kill.

You do know who the deleted member was don't you? 

[brobear]

Mar 4, 2020 15:23:01 GMT -5 tom said:

Mar 4, 2020 5:57:59 GMT -5 King Kodiak said:

Well he just asked hypothetically, what is the largest bear a Brontornis would be able to kill.

You do know who the deleted member was don't you? 

Please enlighten us Tom...