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[EOR]
[BOC]
There are definitely apex predators on Earth that inhabit two of these 'ecosystems', and extinct species that once did. I can't think of any that would inhabit all three, though. (edit: except the [giant petrel](https://en.wikipedia.org/wiki/Giant_petrel))

Terrestrial and aquatic:

* Most crocodiles are unchallenged in freshwater and/or coastal saltwater ecosystems, and nearby river banks and coasts. They generally feed on whatever they want, and even on land they are fast runners and strong enough to defend against pack carnivores (e.g. lions). 

* Killer whales can kill sharks, and have no predators when they remain with the rest of their pods. They also jump onto ice floes and slide along short beaches to hunt seals and walruses.

* Prehistoric Spinosaurus was a semi-aquatic apex predator but large enough to have no predators on land either.


Terrestrial and aerial:

* Large eagles are the apex predators in many ecosystems, preying on most of the land animals in these ecosystems, and being unchallenged in the air.

* Prehistoric azhdarchid pterosaurs like Quetzalcoatlus were so large that they would have had no natural predators on land or in the air, although probably would've spent most of their time on land.


Aerial and aquatic:

* The bald eagle hunts fish and has no natural predators. The similar African fish eagle does the same, but also hunts animals as tall as flamingos.

* The albatross feeds on fish and other marine life, while being one of the largest birds in the sky.
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Safe Follow the [lemmy.world rules.](https://mastodon.world/about) Only tech related content. Be [excellent to each another!](https://www.youtube.com/watch?v=rph_1DODXDU) Mod approved content bots can post up to 10 articles per day. Threads asking for personal tech support may be deleted. Politics threads may be removed. No memes allowed as posts, OK to post as comments. Only approved bots from the list below, to ask if your bot can be added please contact us. Check for duplicates before posting, duplicates may be removed