Among the ocean’s colossal creatures, the blue whale and the whale shark frequently capture public interest due to their immense size. A common question arises regarding which of these two ocean giants is truly the largest. This curiosity stems from their impressive dimensions and their shared characteristic of being filter feeders.
Which is Larger?
The blue whale is larger than the whale shark. It holds the title as the largest animal known to have ever existed on Earth. Blue whales can reach a confirmed length of up to 30.5 meters (100 feet) and weigh up to 199 metric tons (219 short tons). In contrast, the largest confirmed whale shark measured 18.8 meters (61.7 feet) in length and weighed around 21.5 metric tons (23.7 short tons).
The Blue Whale Explained
Blue whales are marine mammals and a type of baleen whale, characterized by filter plates in their mouths instead of teeth. These plates, called baleen, are used to strain vast quantities of krill, tiny shrimp-like crustaceans, from the water. A single blue whale can consume up to four metric tons of krill per day, which fuels its enormous size. Blue whales are found in all oceans, migrating to polar waters in summer to feed on abundant krill and moving towards the equator for breeding in winter. Their long, slender bodies are typically grayish-blue, appearing distinctly blue underwater.
The Whale Shark Explained
The whale shark, a slow-moving, filter-feeding carpet shark, is the largest known extant fish species and the most massive living non-cetacean animal. It belongs to the class Chondrichthyes, meaning it has a cartilaginous skeleton rather than bones. Whale sharks average 4 to 12 meters (13 to 39 feet) in length, with the largest confirmed individual reaching 18.8 meters (61.7 feet). Most studied specimens weigh around 15 metric tons (33,000 pounds).
Whale sharks are filter feeders, primarily consuming plankton, small crustaceans, and small fish, which they strain from the water using specialized filter pads in their broad mouths. Despite their immense size, they are considered docile and pose no threat to humans. They inhabit the open waters of all tropical and warm-temperate oceans, rarely found in waters below 21°C (70°F).
Why the Size Question Arises
The common confusion regarding which animal is larger often stems from shared characteristics and nomenclature. Both are enormous ocean dwellers and filter feeders. This feeding strategy allows both to grow to impressive dimensions. Adding to the misconception, the whale shark carries “whale” in its common name, implying a connection to the blue whale, despite being a fish and not a mammal. Both are truly immense, leading people to wonder about their comparative sizes. Despite these similarities, the blue whale’s evolutionary path as a marine mammal has enabled it to achieve unparalleled dimensions, making it the largest animal on Earth.