Blue Whales 101 | Nat Geo Wild

Summary

Blue whales, the largest animals ever known, grow to massive sizes due to the buoyancy of the ocean, which counteracts the limitations of gravity on land. Their calls, reaching up to 188 decibels, can be heard from over 500 miles away, aiding in long-distance communication. Blue whales can live up to 90 years, with the oldest recorded being 110. Despite their size, their diet mainly consists of tiny krill. They use their baleen to filter out these crustaceans. Once heavily hunted for their valuable body parts, blue whale populations have been recovering thanks to global whaling bans.

Takeaways

• 😀 Blue whales are the largest animals to have ever existed, growing as long as three school buses and weighing as much as 15 blue whales.
• 🌊 The ocean’s buoyancy allows marine mammals like blue whales to grow larger than land animals by overcoming gravity's limitations.
• 🎶 Blue whales have one of the loudest calls in the animal kingdom, reaching up to 188 decibels, louder than jackhammers and jet engines.
• 🔊 Blue whale vocalizations, deep moans and rhythmic low-frequency pulses, can be heard from over 500 miles away.
• 🐋 A blue whale's age can be determined by its earwax, which forms a new layer about every six months, similar to counting tree rings.
• 🎂 The average lifespan of a blue whale is 80 to 90 years, with the oldest known whale living up to 110 years.
• 🍽️ Blue whales consume up to 4 tons of food per day, primarily feeding on krill, despite their massive size.
• 🦐 Krill, tiny crustaceans, are scooped up by the whale's lower jaw, and water is expelled through baleen bristles, which catch the krill.
• 🦷 Baleen, made of keratin (the same material as fingernails), was used in 19th-century fashion items like corsets and collars.
• ❌ Due to high commercial demand, blue whales were nearly driven to extinction, but global bans on whaling have helped the species rebound.

Q & A

What is the size of blue whales compared to other animals?

Blue whales are the largest animals to ever exist, measuring up to the length of about three school buses and weighing as much as 15 blue whales combined. They even outsized dinosaurs.

Why are blue whales able to grow so large compared to land animals?

The ocean provides more room for blue whales to grow and eliminates the limiting factor of gravity. Unlike land animals, the ocean's buoyancy supports their enormous size, which is why marine mammals can grow larger than terrestrial animals.

How does gravity affect the size of land animals?

Gravity limits the size of land animals because their skeletons must support their own weight. This restriction is alleviated for marine animals like blue whales by the buoyancy of water.

How loud are blue whale calls?

Blue whales have one of the loudest calls in the animal kingdom, reaching up to 188 decibels, which is loud enough to overpower the sounds of jackhammers and jet engines.

What purpose do the blue whale's vocalizations serve?

Blue whales use their powerful vocalizations, which include deep moans and rhythmic low-frequency pulses, to communicate with each other over long distances, sometimes up to 500 miles away.

How can a blue whale's age be determined?

A blue whale's age can be estimated by examining the layers of earwax, known as ear plugs, that build up every six months in its ear canal. These layers are similar to counting the rings of a tree trunk.

What is the average lifespan of a blue whale?

The average lifespan of a blue whale is about 80 to 90 years, though the oldest one recorded was about 110 years old.

How much food does a blue whale eat each day?

Blue whales consume up to four tons of food a day, primarily consisting of tiny crustaceans called krill, which is more than the weight of an African elephant.

What is the primary diet of blue whales?

The primary diet of blue whales consists of krill, which are small crustaceans. They use their lower jaws to scoop up large swarms of krill, then filter them through baleen bristles in their mouths.

What is whale baleen made of, and what was it used for historically?

Whale baleen is made of keratin, the same material found in human fingernails. In the 19th century, it was used in fashion for items like corsets, collars, hat brims, and the hoops in skirts.

What caused the near extinction of blue whales, and how is the species recovering?

Blue whales were nearly exterminated due to the high commercial value of their body parts, especially baleen. However, global bans on whaling have been implemented, allowing the species to slowly recover.