Quantity of apex predators and the question of the size of the southern ocean

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Killer whales are apex predators, as no animal preys on them.
Worldwide population estimates are uncertain, but recent consensus suggests a minimum of 50,000. Local estimates include roughly 25,000 in the Antarctic, 8,500 in the tropical Pacific, 2,250–2,700 off the cooler northeast Pacific and 500–1,500 off Norway. Japan's Fisheries Agency estimated 2,321 killer whales were in the seas around Japan.
Half of  the largest apex predator of Global Ocean live in the Southern ocean which is 16 times smaller than Global ocean.
How can this be possible?

Maybe area is not the only factor in population density.

Maybe area is not the only factor in population density.

Not the only one, but very important. In addition, it should be borne in mind that the killer whales are spread almost all over the planet, from the Arctic Ocean to the Mediterranean Sea.
In addition, killer whales share the territory in Antarctica with another apex predator - sea leopard, according to one of estimates, their population reaches 440,000.
No other ocean has such a density of higher predators. And each such predator needs a certain area for hunting (by the way, we can roughly estimate it).

 Quantify "very important" with something other than "I think this is the way it should be."

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Stash

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How can this be possible?
Quite simply, fewer of the ultimate apex predator: Man.

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Space Cowgirl

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What does this have to do with the FE?
I'm sorry. Am I to understand that when you have a boner you like to imagine punching the shit out of Tom Bishop? That's disgusting.

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JackBlack

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Not the only one, but very important. In addition, it should be borne in mind that the killer whales are spread almost all over the planet, from the Arctic Ocean to the Mediterranean Sea.
In addition, killer whales share the territory in Antarctica with another apex predator - sea leopard, according to one of estimates, their population reaches 440,000.
No other ocean has such a density of higher predators. And each such predator needs a certain area for hunting (by the way, we can roughly estimate it).
Firstly, the density of the other predators isn't what is important. It is how much food they take from the food chain.
You are also ignoring another predator, humans, which take loads of fish out of the ocean.
Humans eat roughly 20 kg of fish per person per year. That amounts to roughly 140 000 000 000 kg.

This significantly reduces the amount of food available for the orcas.
However, humans typically don't eat penguins, and don't go fishing too far south.
This makes Antarctica a good place for the orcas.

Yes, there are also sea leopards, and other species of seals which compete for the penguins, while themselves being eaten by the orcas.
Seals are not apex predators, it is the prey of orcas.


What does this have to do with the FE?
I was assuming it was an attempt to claim the southern ocean must be much larger than the globe Earth claims.

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What does this have to do with the FE?
Your guess is as good as mine.

Quantify "very important" with something other than "I think this is the way it should be."

Such a big predator (actually biggest in Global ocean) need a big territory for hunting per each animal.


Firstly, the density of the other predators isn't what is important. It is how much food they take from the food chain.
You are also ignoring another predator, humans, which take loads of fish out of the ocean.
Humans eat roughly 20 kg of fish per person per year. That amounts to roughly 140 000 000 000 kg.

This significantly reduces the amount of food available for the orcas.
However, humans typically don't eat penguins, and don't go fishing too far south.
This makes Antarctica a good place for the orcas.

Industrial fishing is conducted in the same way in the Southern Ocean.

Yes, there are also sea leopards, and other species of seals which compete for the penguins, while themselves being eaten by the orcas.
Seals are not apex predators, it is the prey of orcas.

Orcas don't eat sea leopards.

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JackBlack

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Industrial fishing is conducted in the same way in the Southern Ocean.
Not to the same extent.
It is heavily regulated to avoid any damage to the Antarctic ecosystem.

And again, it isn't getting the penguins and seals that are eaten by the orcas.

Orcas don't eat sea leopards.
Yes they do. They will even knock them off ice to get to them.
https://web.archive.org/web/20110531161550/http://www.grupofalco.com.ar/pedefes/Visser%20et%20al%202008.%20Antarctic%20killer%20whales%20on%20ice%20-%20Marine%20Mammals%20Science.pdf

So do you have an argument and/or a point to make?

Killer whales are apex predators, as no animal preys on them.
Worldwide population estimates are uncertain, but recent consensus suggests a minimum of 50,000. Local estimates include roughly 25,000 in the Antarctic, 8,500 in the tropical Pacific, 2,250–2,700 off the cooler northeast Pacific and 500–1,500 off Norway. Japan's Fisheries Agency estimated 2,321 killer whales were in the seas around Japan.
Half of  the largest apex predator of Global Ocean live in the Southern ocean which is 16 times smaller than Global ocean.
How can this be possible?
I think you may be confusing us with marine biologists.
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I think you may be confusing us with marine biologists.
Such a big predator - orca (actually biggest predator in Global ocean) need a big territory for hunting per each animal. So the actual size of the Southern ocean is much bigger, than in the spherical model of the earth.

Not to the same extent.
It is heavily regulated to avoid any damage to the Antarctic ecosystem.
And again, it isn't getting the penguins and seals that are eaten by the orcas.

There are crabeater seals, by some estimates about  75 million (they eat fish), there are penguins ("the total number of breeding pairs of penguins in the Antarctic region is estimated to be about 20 million") they eat fish too, and so on.

Yes they do. They will even knock them off ice to get to them.
https://web.archive.org/web/20110531161550/http://www.grupofalco.com.ar/pedefes/Visser%20et%20al%202008.%20Antarctic%20killer%20whales%20on%20ice%20-%20Marine%20Mammals%20Science.pdf

I think this is not the main prey. For example, lions sometimes eat hyenas, but this is not their main prey.

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JackBlack

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Such a big predator - orca (actually biggest predator in Global ocean) need a big territory for hunting per each animal. So the actual size of the Southern ocean is much bigger, than in the spherical model of the earth.
Yes, they need a large territory for each animal, but there is still a lot of space in the Southern ocean. It fits fine on the globe.
The current population estimates would be based upon the known area and estimated density.

If you want this to be taken as a rational argument you will need more than "they need more space".
Perhaps start with an estimate of just how much space you think each one needs, with a justification of why, and then compare that to the size of the southern ocean.

There are crabeater seals, by some estimates about  75 million (they eat fish), there are penguins ("the total number of breeding pairs of penguins in the Antarctic region is estimated to be about 20 million") they eat fish too, and so on.
Yes, so lots of food for them there.

I think this is not the main prey. For example, lions sometimes eat hyenas, but this is not their main prey.
Sure it might not be the main prey, but they still hunt and eat them.


Perhaps start with an estimate of just how much space you think each one needs, with a justification of why, and then compare that to the size of the southern ocean.

It's a big work for the team of scientists.

Yes, so lots of food for them there.
"When the minke whales arrive in larger numbers, and the type-C killer whales, too, we can expect the penguins to have more difficulty finding food. These whales go after the same food as the penguins, and take much more of it in one gulp!"

And there are orcas that eat fish.


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JackBlack

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It's a big work for the team of scientists.
So what you are saying is that you have no idea and thus no basis for your claim that the southern ocean must be larger?

And there are orcas that eat fish.
I know. That doesn't mean that they will only eat fish.
Fish are typically the easier prey as they are already in water and can't retreat to land.
And that doesn't mean there isn't enough for them to eat.