Dolphins (Junior)

DOLPHINS
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Slide 1: Tekstslide
Social StudiesHistory+3Age 51st,2nd Grade

In deze les zitten 31 slides, met interactieve quizzen, tekstslides en 2 videos.

time-iconLesduur is: 45 min

Introductie

This lesson discusses dolphin species, why they are important and the threats they are currently facing. This lesson will take 45 minutes to complete.

Instructies

This lesson is about dolphin species, some of the issues harming dolphins and what everyone can do to help keep them safe.

Time: 45 minutes

Contact: education@seashepherdglobal.org
© Sea Shepherd 2021

Onderdelen in deze les

DOLPHINS

Slide 1 - Tekstslide

This lesson is provided by Sea Shepherd.  Sea Shepherd is a marine conservation organisation with a mission to protect the ocean and marine wildlife.  Sea Shepherd works globally on a range of issues impacting the ocean, running numerous direct action campaigns each year.  Dolphins are one species that Sea Shepherd is fighting to protect.
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Watch  the video

Slide 2 - Tekstslide

During the lesson we will use these icons to identify the learning actions.
Introduction to IUU fishing and the impact of overfishing.
Protecting dolphins.

Slide 3 - Tekstslide

This lesson is about dolphin species, some of the issues harming dolphins and what everyone can do to help keep them safe.

INTERACTIVE JOIN – ask students to go to www.LessonUp.app

Illegal Fishing
Illegal fishing means that the fishermen enter the territorial waters of a country or regulated marine zone without permission or without a license for the fish they intend to catch.

They are stealing from these waters.
Over 30 species of dolphin.

Most are ocean living, five live in rivers.

Seven species of porpoises.

Slide 4 - Tekstslide

Dolphins
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.

Illegal Fishing
Illegal fishing means that the fishermen enter the territorial waters of a country or regulated marine zone without permission or without a license for the fish they intend to catch.

They are stealing from these waters.
CETACEAN FAMILY

Whales and dolphins are part of the cetacean family.

Two groups:
➢    Baleen whale
➢    Toothed whales - includes dolphins and porpoises.


Slide 5 - Tekstslide

Whales and dolphins
All whales and dolphins are part of the family called cetaceans.

Two types of cetacheans:
  • Baleen whales – these are the ones that scoop up water, including fish and krill in their mouths – filter feed.
  • Toothed whales

Dolphins and porpoises are part of the toothed whale family.

Over 100 million tons of fish caught each year.
Dolphin or porpoise?

Slide 6 - Tekstslide

Dolphin or porpoise?
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-shaped teeth, the dorsal fin is more triangular shaped.  They also don’t communicate as much as dolphins.

Illegal Fishing
Illegal fishing means that the fishermen enter the territorial waters of a country or regulated marine zone without permission or without a license for the fish they intend to catch.

They are stealing from these waters.
PORPOISE

Seven porpoise species

Vaquita is the smallest and critically endangered.

Slide 7 - Tekstslide

Vaquita porpoise
The Vaquita is the smallest porpoise at 1.5m (5 feet) and weights about 54kg (119lbs).  With less than twenty left the Vaquita is critically endangered, which means they might be extinct in the near future (disappear from the ocean forever).

They are only found in one place in the world, in the Gulf of California off Mexico, also known as the Sea of Cortez.

Over 100 million tons of fish caught each year.
Orca

Slide 8 - Tekstslide

Orca are the largest of the dolphin family.

Their original name was actually Whale Killer as they are one of the few species on this planet that will hunt and eat whales, some much bigger than themselves.  They are very intelligent animals, that work as a team to hunt for food.

Orca’s live in family pods and can live for over 100 years.


Over 100 million tons of fish caught each year.
Bottlenose dolphins

Slide 9 - Tekstslide

Bottlenose dolphins are the most common and well-known dolphins.   They grow up to 4m (13 feet) and weight about 590kg (1,300lbs).  They can live up to 40-60 years.
Over 100 million tons of fish caught each year.
Hectors dolphins

Slide 10 - Tekstslide

Hector’s dolphins
Hector’s dolphins are the rarest species of dolphin, which means they are at serious risk of disappearing from the ocean. They are only found in New Zealand waters.  They have unique colouring and the dorsal fin on their back is rounded.  

Maui dolphins are part of the hector’s dolphin family and there are less than 100 of them left.

Illegal Fishing
Illegal fishing means that the fishermen enter the territorial waters of a country or regulated marine zone without permission or without a license for the fish they intend to catch.

They are stealing from these waters.
DOLPHIN CALF

Stay with mum for 18 months to 8 years, depending on species.

Close bond between mum and calf.

Slide 11 - Tekstslide

Dolphin calf
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.  Mum feeds baby until it is big enough to eat solid foods.

Dolphin calves spend most of their early months swimming next to 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.

Over 100 million tons of fish caught each year.
Dolphins are intelligent beings.

Slide 12 - Tekstslide

Intelligent species
Dolphins are really intelligent. They have a brain larger than humans.

They show signs that they experience similar feelings like we do – pain, love and sadness when they lose a family member.


Over 100 million tons of fish caught each year.
What do dolphins eat?

Slide 13 - Tekstslide

What do dolphins eat?
Dolphins mainly eat small fish, crustaceans and squid. Crustacean are animals like krill, prawns, crabs and crayfish, they all have a shell.

Larger species 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, to 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 14 - Video

Dolphin language
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

Over 100 million tons of fish caught each year.
Echolocation

Slide 15 - Tekstslide

Echolocation
Whales and dolphins use echolocation to find their way and hunt for fish.

Echolocation means they send out a sound and listen for the echoes that come back. These echoes tell them what objects or animals are in the area.

See the Lesson Activity Sheet – Echolocation Activity.

Over 100 million tons of fish caught each year.
Role in the ocean ecosystem.

Slide 16 - Tekstslide

Important to the ocean
Dolphins, like whales and sharks play a very important part in the ocean and help to keep the ecosystem in balance. Dolphins help control populations of fish and squid, keeping the numbers under control, which balances the impact of each species in the ecosystem.

Ecosystem means a biological community of interacting organisms and their physical environment.
Which is a community of living beings that work together with their environment. Like a reef, with corals, fish and sharks,

Over 100 million tons of fish caught each year.
Predators.

Slide 17 - Tekstslide

Predator
There is one natural predator of dolphins, which is the shark. But sharks have to be careful as dolphins can put up a fight.  If a shark tries to attack a dolphin it can find its self being charged at by a group of dolphins defending their pod. The shark might end up losing the fight.

Over 100 million tons of fish caught each year.
By-catch in commercial fishing nets.  Each year 300,000 dolphins and whales die in fishing nets.

Slide 18 - Tekstslide

By-catch
Dolphins get caught in the nets of large fishing vessels. The nets are so big they can trap whole dolphin pods.  Often the dolphins don’t get released in time and die.

To help protect dolphins we have to make sure the fishing vessels do the right thing and watch out for dolphin pods when they are putting out their nets, and that dolphins caught in the nets should be released quickly.

Ask students why they think dolphins get caught in nets?
  • The dolphins and the fishing vessels both want to catch the same fish.

Over 100 million tons of fish caught each year.
Entangled in abandoned, lost or discarded fishing gear. Ghostnet - can you see the net?

Slide 19 - Tekstslide

Entanglement
Each year a lot of fishing gear is lost or left behind in the ocean by fishing vessels. These nets float in the ocean catching marine wildlife and can entangle dolphins.  

Imagine dolphins swimming and all of a sudden they get caught in fishing nets and lines. They have to float there or swim along all entangled until someone helps them. Unfortunately, not all of them find help in time.

Ask students how we can help stop the dolphins becoming entangled?
  • By helping to clean up fishing gear from the ocean.
  • Making the fishing vessels clean up their own fishing gear properly.

Teacher’s note: Each year 640,000 tonnes of fishing gear is lost, abandoned or discarded at sea by the commercial fishing industry.

Over 100 million tons of fish caught each year.
Plastic pollution.

Slide 20 - Tekstslide

A sea of plastic
Every day all over the world rubbish is finding its way into the ocean. It is estimated that this rubbish amounts to more than one garbage truck dumping trash in the ocean every 40 seconds – imagine all that rubbish floating in the ocean.

All kinds of trash are left behind at beaches or in waterways to be washed out to sea, dumped at sea from boats or lost s from container ships in storms.

Teacher’s note: Over 12 million tonnes of trash is finding its way into the ocean each year.  This amount is growing each year.  

Over 100 million tons of fish caught each year.
Why is trash a problem?

Slide 21 - Tekstslide

Why is trash in the ocean a problem?
Ask students why they think this is an issue for dolphins?

They can’t always distinguish the difference between rubbish and food and when they do they might already have swallowed it, or caught up and entangled in it, unable to free themselves.


Illegal Fishing
Illegal fishing means that the fishermen enter the territorial waters of a country or regulated marine zone without permission or without a license for the fish they intend to catch.

They are stealing from these waters.
HOW CAN WE STOP TRASH

?

Slide 22 - Tekstslide

Stopping the trash
Ask students  “What do you think we can do to stop this trash ending up in the ocean?”

Teacher’s note:
You can discuss things like:
    Reducing single use plastics.
    Using reusable products.
    How to properly dispose of rubbish.
    Recycling plastics.
    Doing clean ups. 
Over 100 million tons of fish caught each year.
Dolphin captivity.

Slide 23 - Tekstslide

Dolphin captivity
There are people who hunt dolphins for captivity.  Captivity means dolphins are taken from the ocean and put in pools at marine parks. The dolphins are trained to entertain people and do tricks.

Who doesn’t love watching dolphins swim and jump around in the water, but captivity is no fun for dolphins, neither bottlenose dolphins nor orcas.

Ask the children why they think being in captivity might not be fun for dolphins?

These are some of the problems with captivity that could be discussed:

  •     Dolphins are fed dead fish rather than fresh – not as healthy as in the wild, where they would naturally hunt together for live fish.
  •     Taken from their family groups – how would you feel being separated from your family & friends?
  •     Put into tanks with foreign animals that may not communicate the same as them – Think how scary it would be being stuck in a foreign country not speaking the language.
  •     Size of the tanks – instead of open ocean they spend the rest of their lives in a tiny pool or pen where they can only swim in circles.
  •     No stimulation – no fish to catch, no ocean currents, or waves, and sounds used for echolocation bouncing off the concrete walls all the time.
  •     They are kept hungry and forced to learn tricks for food just to entertain us.


Over 100 million tons of fish caught each year.
Where should dolphins be?

Slide 24 - Tekstslide

Where do dolphins belong?
In the bath tub with the rubber ducky?
In the pond with frogs and lilies?
In the pool with you and me?
Or swimming in the deep blue sea?

The bath tub is too small!
The pond is too swallow!
The pool is to short.
So dolphins must belong swimming free in the sea.

What do you like most about dolphins?

Slide 25 - Open vraag

What do you like most about dolphins?
Ask students to answer the following question using www.LessonUp.app or write on paper:
 
 “What do you like most about dolphins?”


Write down one issue that we talked about
that is harming dolphins?

Slide 26 - Open vraag

What is harming dolphins?
Ask students to answer the following question using www.LessonUp.app or write on paper:

 “Write down one issue that we talked about that is harming dolphins?”


Write down one thing that you can do to
help protect dolphins?

Slide 27 - Open vraag

How can we help dolphins?
Ask students to answer the following question using www.LessonUp.app or write on paper:
 
 “Write down one thing that you can do to help protect dolphins?”



Write down one new thing you have learned today?

Slide 28 - Open vraag

What did you learn?
Ask students to answer the following question using www.LessonUp.app or discuss in the classroom:  

“Write down one new thing you have learned today?”



Write down one thing you didn't understand?

Slide 29 - Open vraag

What don’t you understand?
Ask students to answer the following question using www.LessonUp.app or write on paper:  

“Write down one thing you didn’t understand?”


Slide 30 - Video

Sea Shepherd Lesson Activity Sheets provide additional lesson activities or discussion topics to expand the learning experience.

Optional fun video
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

www.seashepherdglobal.org

Slide 31 - Tekstslide

Deze slide heeft geen instructies