Who lives in the ocean? - Lesson Three
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La durée de la leçon est: 45 minIntroduction
Lesson 3 – Can dolphins talk?
This lesson covers:
What features do dolphins have?
What do dolphins eat?
How do dolphins talk?
Learning activities:
How echolocation works.
Writing and discussion exercises on what has been learned.
Instructions
Time: 45 minutes
Contact: education@seashepherdglobal.org
© Sea Shepherd 2022
Éléments de cette leçon
Slide 1 - Diapositive
This lesson is provided by Sea Shepherd. Sea Shepherd was founded in 1977 and is a marine conservation organisation working to protect the oceans and marine wildlife. Sea Shepherd works globally on a range of issues impacting the oceans, running numerous direct action campaigns each year. The protection of dolphins is one area Sea Shepherd is working in.
Slide 2 - Diapositive
During the lesson we will use these icons to identify the learning actions.
Slide 3 - Diapositive
There are over 30 species of dolphin, most live in the ocean but there are some that live in rivers.
There are also seven species of porpoises.
All whales and dolphins are part of the family called cetaceans.
There are two types of cetaceans:
Ø Baleen whales – these are the ones that scoop up water, including fish and krill in their mouths – filter feed.
Ø Toothed whales
Dolphins and porpoises are part of the toothed whale family.
There are also seven species of porpoises.
All whales and dolphins are part of the family called cetaceans.
There are two types of cetaceans:
Ø Baleen whales – these are the ones that scoop up water, including fish and krill in their mouths – filter feed.
Ø Toothed whales
Dolphins and porpoises are part of the toothed whale family.
Slide 4 - Diapositive
Ask students: “Do you know the difference between a dolphin and porpoise?”
Can you see any differences between the two images?
Dolphins tend to have a longer beak, bigger mouths and more curved dorsal fins.
Porpoise have smaller mouths with spade (square) shaped teeth, the dorsal fin is more triangular shaped. They also don’t communicate as much as dolphins.
Can you see any differences between the two images?
Dolphins tend to have a longer beak, bigger mouths and more curved dorsal fins.
Porpoise have smaller mouths with spade (square) shaped teeth, the dorsal fin is more triangular shaped. They also don’t communicate as much as dolphins.
Slide 5 - Diapositive
Use the image to explain the dolphin life cycle.
Dolphins are mammals, like us, so they have babies, called calves. A calf will stay with its mum for 18 months to 8 years depending on the species. Mums feed their baby until it is big enough to eat solid foods.
Dolphin calves spend most of their early months swimming next to their mum or even ride on her back, this helps it to keep up with the pod.
The bond between mum and baby is similar to ours, so the mums get really sad when they lose a baby.
Dolphins are mammals, like us, so they have babies, called calves. A calf will stay with its mum for 18 months to 8 years depending on the species. Mums feed their baby until it is big enough to eat solid foods.
Dolphin calves spend most of their early months swimming next to their mum or even ride on her back, this helps it to keep up with the pod.
The bond between mum and baby is similar to ours, so the mums get really sad when they lose a baby.
Slide 6 - Diapositive
Dolphins live in rivers and the open ocean. (Image of a river dolphin and an ocean dolphin)
Slide 7 - Diapositive
Dolphins mainly eat small fish, crustaceans and squid. Crustaceans are animals like krill, prawns, crabs and crayfish, they all have a shell.
Larger dolphins like orca’s will feed on whales, sharks, seals and other dolphins.
Dolphins are really smart and work together as a team when hunting. If they find a school of fish, they slowly circle around them, so they can herd the fish together. When hunting close to shore they use their tails to kick up dirt from the ocean floor in order to make a circle of murky water around the fish. Then as the fish try to jump out of the water over the dirty water, they catch them.
Dolphins have also been seen using tools to help them hunt like using sea sponges on their rostrum (nose) to protect it while they dig around on the seabed looking for food. This protects them from pieces of rock or broken coral. Pretty smart.
Larger dolphins like orca’s will feed on whales, sharks, seals and other dolphins.
Dolphins are really smart and work together as a team when hunting. If they find a school of fish, they slowly circle around them, so they can herd the fish together. When hunting close to shore they use their tails to kick up dirt from the ocean floor in order to make a circle of murky water around the fish. Then as the fish try to jump out of the water over the dirty water, they catch them.
Dolphins have also been seen using tools to help them hunt like using sea sponges on their rostrum (nose) to protect it while they dig around on the seabed looking for food. This protects them from pieces of rock or broken coral. Pretty smart.
Slide 8 - Vidéo
Dolphins have their own language, even within each group or pod they will have their own form of communication. Unique sounds like clicks that they use to talk to each other.
Show this video (1.16 mins), which shows a pod of pantropical spotted dolphins. Listen to their communication sounds: https://youtu.be/kLAtfDnLCUc
Show this video (1.16 mins), which shows a pod of pantropical spotted dolphins. Listen to their communication sounds: https://youtu.be/kLAtfDnLCUc
Slide 9 - Vidéo
Show this video (1.01 mins), which shows a super pod of dolphins visiting the Sea Shepherd vessel Bob Barker: https://youtu.be/Ak2p8O-szBY
Slide 10 - Diapositive
Cet élément n'a pas d'instructions
Slide 11 - Diapositive
Refer Teachers Guide for Learning Activities.
