ClassX Video Lessons Youtube Channel Real Science How do narwhals dive all the way to the ocean midnight zone?
Narwhals are amazing creatures known for their incredible diving abilities. These fascinating animals can dive as deep as 1,800 meters into the ocean, especially during the winter months when they hunt for food. They are able to perform between 18 to 25 dives each day!
Narwhals have some special features that help them dive so deep. First, they have thick blubber, which is a layer of fat that keeps them warm in the icy waters and provides energy. Their ribs can collapse, or bend, under the high pressure of deep water, which helps protect their bodies.
Another cool thing about narwhals is their ability to store a lot of oxygen. They can hold up to 70 liters of oxygen in their lungs, blood, and muscles. This allows them to stay underwater for a long time without needing to come up for air.
Unlike dolphins, which have fast-twitch muscles for quick bursts of speed, narwhals have muscles that are better for long-distance swimming. This means they use less oxygen and can swim for longer periods without getting tired.
Even though narwhals only have two teeth, they are skilled hunters. They eat large fish like Arctic cod and gonatus squid. Narwhals use a special technique called echolocation to find their prey in the dark waters. Echolocation is like using sound waves to “see” underwater.
Once they find their prey, narwhals use a method called suction feeding to eat. They create a vacuum in their mouth by pulling back their tongue, which sucks the fish in. This way, they can swallow their food whole without needing to chew.
Did you know that the long tusk of a narwhal is actually a tooth? It’s one of the two teeth they have, and it can grow up to 3 meters long!
Narwhals are truly remarkable animals with unique adaptations that allow them to thrive in the deep, cold waters of the Arctic. Their diving skills and hunting techniques make them one of the most interesting creatures in the ocean.
Imagine you are a narwhal diving deep into the ocean. Use a large piece of paper to draw a cross-section of the ocean, marking different depths. Label the “Midnight Zone” and other ocean layers. Then, use a small narwhal cutout to simulate dives, noting how deep you can go and what challenges you might face at each level.
Discover how blubber keeps narwhals warm. Fill two ziplock bags with vegetable shortening to simulate blubber. Place one bag inside another and seal it. Then, put your hand inside the blubber bag and dip it into ice-cold water. Notice how your hand stays warm, just like a narwhal’s body in icy waters.
Learn about oxygen storage by holding your breath and timing how long you can last. Compare this to the narwhal’s ability to hold up to 70 liters of oxygen. Discuss how their bodies are adapted to store more oxygen and what advantages this gives them in deep-sea diving.
Experience echolocation by playing a game of “Marco Polo” with a twist. One student is the “narwhal” and must find their “prey” (another student) using only sound. The “prey” makes a noise, and the “narwhal” uses the sound to locate them, simulating how narwhals find food in dark waters.
Try out suction feeding using a straw and small pieces of food like cereal or marshmallows. Place the food in a bowl of water and use the straw to create a vacuum to suck up the pieces. This demonstrates how narwhals use suction to catch their prey without chewing.
Narwhals are one of the deepest divers, swimming as far as 1,800 meters underwater to hunt for food, especially deep in the winter. They manage 18 to 25 dives per day, thanks to their thick blubber that provides insulation and energy, collapsible ribs that bend under high pressures, and an incredible ability to store 70 liters of oxygen in their lungs, blood, and muscles. Their bodies don’t have the fast-twitch skeletal muscles that give dolphins such explosive speeds; instead, they have muscles better suited for endurance swimming, requiring less oxygen. Despite the fact that narwhals only have two teeth, which are not adapted for chewing, they actually eat fairly sizable fish, including Arctic cod and gonatus squid. They find their prey using echolocation and then swallow them whole using a strategy called suction feeding. Essentially, they create a vacuum in their mouth by retracting their tongue and slurp up the fish.
Narwhals – Narwhals are medium-sized whales known for their long, spiral tusks that can grow up to 10 feet long. – Narwhals live in the cold Arctic waters and use their tusks to sense their environment.
Dive – To dive means to plunge into water or to go deep underwater. – Dolphins can dive deep into the ocean to catch fish.
Ocean – The ocean is a vast body of saltwater that covers most of the Earth’s surface. – The Pacific Ocean is the largest and deepest ocean in the world.
Blubber – Blubber is a thick layer of fat under the skin of marine animals that helps keep them warm in cold water. – Seals have a lot of blubber to help them survive in icy waters.
Oxygen – Oxygen is a gas that animals need to breathe in order to survive. – Fish get oxygen from the water through their gills.
Swimming – Swimming is the act of moving through water by using the limbs or body. – Turtles are excellent at swimming and can travel long distances in the ocean.
Echolocation – Echolocation is a method used by some animals to locate objects by emitting sounds and listening for the echoes. – Bats and dolphins use echolocation to find food and navigate their surroundings.
Prey – Prey refers to animals that are hunted and eaten by other animals. – The owl silently swooped down to catch its prey, a small mouse.
Suction – Suction is the process of drawing something in by creating a vacuum or low-pressure area. – Octopuses use suction cups on their tentacles to grab onto rocks and prey.
Adaptations – Adaptations are special features or behaviors that help an animal or plant survive in its environment. – Camels have adaptations like humps to store fat, which helps them survive in the desert.
