* Limited data: We don't have complete population data for all shark species.
* Varying distribution: Some sharks might be rare in certain areas but more common in others.
* Deep-sea species: Many sharks live in the deep ocean, making them very difficult to study and estimate their population size.
However, some contenders for the title of "least common" shark include:
* Goblin shark: These bizarre-looking sharks live in deep waters and are rarely encountered.
* Megamouth shark: This massive shark is known from only a few dozen specimens, mostly captured as bycatch.
* Dwarf lanternshark: This tiny shark is also a deep-sea dweller and very little is known about its population.
It's important to remember that all sharks are facing threats from overfishing, habitat destruction, and climate change, and conservation efforts are crucial to protect these fascinating creatures.