Is A Whale shark A Whale?

Quick Facts

Attribute	Details
Type	Marine fish
Family	Rhincodontidae
Habitat	Oceans worldwide
Conservation	Protected in most countries
Research Status	Ongoing scientific study

The Short Answer

No, a whale shark is not a whale - it’s a fish. The whale shark (Rhincodon typus) is the largest fish in the world, growing up to 40+ feet (12+ meters) in length. Its name comes from its enormous, whale-like size and its filter-feeding behavior similar to baleen whales, but biologically it’s completely different. Whale sharks are cold-blooded fish that breathe through gills, while whales are warm-blooded mammals that breathe air.

Whale Shark vs. Whale: Key Differences

Understanding why whale sharks aren’t whales requires comparing their fundamental biology:

Characteristic	Whale Shark	Whales
Classification	Fish (Chondrichthyes)	Mammals (Mammalia)
Breathing	Gills	Lungs (breathe air)
Body Temperature	Cold-blooded	Warm-blooded
Reproduction	Lays eggs/live birth	Live birth, nurses young
Skin	Rough, covered in denticles	Smooth, with blubber
Skeleton	Cartilage	Bone
Tail Movement	Side-to-side	Up-and-down

Whale Shark Statistics

Whale sharks are remarkable creatures in their own right:

Measurement	Value	Comparison
Maximum Length	40-60 ft (12-18 m)	Size of a school bus
Average Length	25-35 ft (7.6-10.7 m)	Half a basketball court
Maximum Weight	41,000 lbs (18,600 kg)	Weight of 4 elephants
Mouth Width	5 ft (1.5 m)	Could fit a small car tire
Lifespan	70-100+ years	Similar to humans
Swimming Speed	3 mph (5 km/h)	Slow walking pace

Why “Whale Shark”? The Name Explained

The name “whale shark” comes from two characteristics:

Feature	Similarity to Whales	Reality
Size	Massive like whales	Largest fish, not whale
Filter Feeding	Feeds like baleen whales	Uses gill rakers, not baleen
Gentle Nature	Docile like many whales	Harmless to humans
Slow Movement	Cruises like large whales	Fish-like swimming
Plankton Diet	Eats same food as some whales	Convergent evolution

This is an example of convergent evolution - where unrelated species develop similar traits to fill similar ecological niches.

Classification Comparison

Level	Whale Shark	Blue Whale
Kingdom	Animalia	Animalia
Phylum	Chordata	Chordata
Class	Chondrichthyes (fish)	Mammalia (mammals)
Order	Orectolobiformes	Artiodactyla
Family	Rhincodontidae	Balaenopteridae
Genus	Rhincodon	Balaenoptera
Species	R. typus	B. musculus

The classification diverges at the Class level - whale sharks are in the class of cartilaginous fish, while whales are mammals.

Filter Feeding: Similar Strategy, Different Anatomy

Both whale sharks and some whales are filter feeders, but they do it differently:

Feature	Whale Shark	Baleen Whale
Filter Structure	Gill rakers	Baleen plates
Material	Cartilage	Keratin (like fingernails)
Filtering Method	Water over gills	Gulp and push water out
Daily Food Intake	45 lbs (20 kg)	4,000-8,000 lbs (1,800-3,600 kg)
Primary Food	Plankton, small fish	Krill, small fish

Frequently Asked Questions

Why isn’t a whale shark classified as a whale?

Whale sharks lack all the defining characteristics of mammals. They don’t breathe air, don’t nurse their young with milk, are cold-blooded, and have cartilage skeletons instead of bones. Whales, despite living in water, share their mammalian traits with land animals like dogs and humans.

Are whale sharks dangerous like some sharks?

No, whale sharks are completely harmless to humans. Despite being sharks, they are filter feeders with tiny teeth they don’t use for biting. Divers regularly swim alongside whale sharks safely. Their mouths, while enormous, are designed only for filtering small organisms from water.

How can you tell a whale shark from a whale in the water?

Several visible differences help identify them:

• Tail movement: Whale sharks move tails side-to-side; whales move tails up-and-down
• Breathing: Whale sharks don’t surface to breathe; whales must surface regularly
• Fin shape: Whale sharks have vertical tail fins; whales have horizontal flukes
• Pattern: Whale sharks have distinctive spotted patterns; most whales don’t

Is the whale shark the biggest fish or biggest shark?

Both! The whale shark is the largest living fish species of any kind and also the largest shark species. The second-largest fish is the basking shark, another filter-feeding shark that reaches about 26 feet (8 meters).

Do whale sharks and whales ever interact?

While they may occasionally share the same waters, whale sharks and whales don’t typically interact. They occupy different ecological niches despite both being large filter feeders. Whale sharks prefer tropical and warm temperate waters, while many large whales prefer cooler waters or migrate between regions.

Size Comparison: Whale Shark vs. plankton, fish eggs, small fish Whales

Species	Average Length	Maximum Length	Classification
Whale Shark	25-35 ft (7.6-10.7 m)	60 ft (18 m)	Fish
Blue Whale	80-100 ft (24-40-60 feet (12-18 meters))	110 ft (33.5 m)	Mammal
Humpback Whale	48-62 ft (15-19 m)	62 ft (19 m)	Mammal
Orca (Killer Whale)	20-26 ft (6-8 m)	32 ft (10 m)	Mammal
Minke Whale	25-30 ft (7.6-9 m)	35 ft (10.7 m)	Mammal

While whale sharks are enormous for fish, they’re smaller than the largest whales but comparable to mid-sized whale species.

Conservation Status

Both whale sharks and many whale species face conservation challenges:

Species	IUCN Status	Population Trend	Main Threats
Whale Shark	Endangered	Decreasing	Fishing, bycatch
Blue Whale	Endangered	Increasing	Ship strikes
Humpback Whale	Least Concern	Increasing	Entanglement
Fin Whale	Vulnerable	Increasing	Hunting

Learn more about what is a whale shark and what whale sharks eat.

Key Takeaway

The whale shark’s name is descriptive but misleading. It’s called a “whale shark” because of its enormous size and gentle, filter-feeding nature - characteristics it shares with baleen whales. However, it remains 100% fish, sharing more in common with a great white shark than with any whale species.

Related Questions

• Where Do Whale Sharks Live?
• What is a Whale Shark?
• What Does the Whale Shark Eat?
• What is a Whale?