Cette leçon contient 32 diapositives, avec quiz interactifs, diapositives de texte et 1 vidéo.
La durée de la leçon est: 45 min
Introduction
Sea turtles are under threat from a number of human interactions including pollution, coastal development, abandoned fishing gear, by-catch in commercial fishing nets and poaching.
Instructions
This lesson focuses on sea turtles and the reasons why they are endangered.
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. Sea turtles are one species Sea Shepherd is helping to protect.
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Slide 2 - Diapositive
During the lesson we will use these icons to identify the learning actions.
Illegal poaching endangering sea turtles.
Sea turtles and why they are endangered.
Slide 3 - Diapositive
This lesson focuses on one of the main reasons why sea turtles are endangered – poaching.
INTERACTIVE JOIN – ask students to go to www.LessonUp.app
Slide 4 - Vidéo
Empty ocean by 2050 Scientists estimate that by 2050 the ocean ecosystem will be on the verge of collapse, empty of fish and marine wildlife, unless urgent action is taken on the issues impacting on the oceans and marine wildlife.
Show this video (2.53min), which explains how important all species are to our planet. https://www.youtube.com/watch?v=TLcA31VRlRU
Discuss the video with the class and what it means.
Current sea turtle species appeared
over 100 million years ago.
Current sea turtle species appeared over 100 million years ago.
Slide 5 - Diapositive
Sea turtles Sea turtles as a species have existed since the time of the dinosaurs, with the current species of sea turtles starting to appear over 100 million years ago.
Seven main species of sea turtle.
Seven main species of sea turtle.
Slide 6 - Diapositive
Sea Turtle species There are 7 main sea turtle species Ask students to name the sea turtle species they know.
Hawksbill
Green
Loggerhead
Leatherack
Slide 7 - Question de remorquage
Match the images Using www.LessonUp.app ask students to match the image of the sea turtle to its name.
Sea Turtle species
SEA TURTLE SPECIES
Hawksbill Weight up to 70kg (154pounds) 90cm (3 feet). Hawks beak, which allows to get food from coral reefs. 2 claws on front flippers.
Olive Ridley 70 cm (2.5 feet) 45kg(100pounds). Olive green shell colour. Front and rear flippers have a claw.
Slide 8 - Diapositive
Hawsbill and Olive Ridley Ask students to share facts they know about these species of sea turtle:
What are the shells made of?
How long can they dive for?
How long do they live?
What do they eat?
The 7 species of sea turtles are:
Hawksbill
Weight up to 70kg (154 pounds) 90cm (3 feet).
Hawks beak, which allows them to get food from coral reefs.
2 claws on front flippers.
Olive Ridley
70 cm (2.5 feet) 45kg (100 pounds).
Olive green shell colour.
The front and rear flippers have a claw.
Sea turtle species
SEA TURTLE SPECIES
Kemp Ridley 66 cm (2feet) 50 kg (110 pounds). Dark green shell, while underside is white or yellowish.
Green Grow to 1.1m (4 feet) long and up to 190kg (420 pounds). Brown to olive shell, but have green skin.
Slide 9 - Diapositive
Kemp Ridley and Green Ask students to share facts they know about these species of sea turtle:
What are shells made of?
How long can they dive for?
How long do they live?
What do they eat?
Kemp Ridley
66 cm (2feet) 50 kg (110 pounds).
Dark green shell, while underside is white or yellowish.
Green
Grow to 1.1m (3.5 feet) long and up to 190kg (420 pounds).
Brown to olive shell, but have green skin.
SEA TURTLE SPECIES
Loggerhead 110 cm (3.5 feet) 170kg (375 pounds). Large head, reddish brown shell.
Leatherback Thin layer of tough skin over shell that gives it the appearance of leather. 183cm (6 feet) 500kg (1,100 pounds).
Flatback Shell is flat compared to other turtles. 99cm (3.25 feet) and 90kg (198 pounds).
Slide 10 - Diapositive
Loggerhead, Leatherback and Flatback sea turtles Ask students to share facts they know about these species of sea turtle:
What are the shells made of?
How long can they dive for?
How long do they live?
What do they eat?
Loggerhead
110 cm (3.5 feet) 170kg (375 pounds).
Large head, reddish brown shell.
Leatherback
Thin layer of tough skin over shell that gives it the appearance of leather.
183cm (6 feet) 500kg (1,100 pounds).
Flatback
Shell is flat compared to other sea turtles.
99cm (3.25 feet) and 90kg (198 pounds).
6 of 7 species are endangered
or critically endangered
• Hawksbill and Kemp’s Ridley - critically endangered • Green and Loggerhead - endangered • Leatherback and Olive Ridley - vulnerable • Flatback turtles are the only ones not currently listed as endangered, but it is listed as endangered in Australia.
Slide 11 - Diapositive
Facing extinction Endangered status of sea turtles. 6 of the 7 species are currently endangered or critically endangered.
Hawksbill and Kemp’s Ridley - critically endangered.
Green and Loggerhead – endangered.
Leatherback and Olive Ridley – vulnerable.
Flatback turtles are the only ones not currently listed as endangered, but are listed as endangered in Australia.
Seven main species of sea turtle.
Predators
Slide 12 - Diapositive
Predators Sea turtles have a tough start to life. Hatchlings face a lot of hazards just trying to make it to the ocean and survive their first few years.
Many hatchlings fall prey to crabs and birds as they make their way into the sea. Animals like foxes will dig up the nests and eat the eggs, as well as attack the mums when they come ashore to nest.
In the ocean hatchlings face threats from large fish and sharks whilst adult turtles will fall prey to sharks, seals and orcas.
Seven main species of sea turtle.
Only 1 out of 1,000 sea turtle hatchlings survive to adults.
Slide 13 - Diapositive
Early years
Turtles drift on ocean currents during the early years of their life before moving in closer to shore to feeding grounds. They will travel long distances to find their feeding ground or to nest on a beach.
Turtles are slow growing and take decades to reach maturity. They can live as long as humans do, and sometimes longer.
Only 1 out of 1,000 sea turtles survives to adulthood from the eggs hatched.
What do you think are the main reasons why sea turtles are endangered?
Slide 14 - Carte mentale
Ask students to answer the following question using www.LessonUp.app or discuss in the classroom.
“What do you think are the main reasons why sea turtles are endangered?”
Why do you think sea turtles are taken by poachers?
Slide 15 - Question ouverte
Sea turtle poaching Ask students to answer the following question using www.LessonUp.app or discuss in the classroom.
Why do you think sea turtles are widely taken by poachers? (What do they use them for?)
For turtle meat, eggs and
the shells to make ornaments.
For turtle meat, eggs and the shells to make ornaments.
Slide 16 - Diapositive
Poaching The main reasons for poaching are:
Turtle meat.
Eggs taken for food.
Shells – used to make ornaments and jewellery, often for tourists.
Female turtles come ashore for nesting season, where they lay their eggs on beaches.
Sea turtles are slow moving and spend a lot of time digging a nest, laying eggs, burying the eggs and then heading back to sea again. Poachers wait until the eggs are laid and then attack the female turtle.
Female turtles often nest on the same beach where they were born. Nesting season is a regular occurrence, so poachers know what time of year to monitor the beaches and watch for turtles.
Female turtle coming ashore to nest.
By-catch in commercial fishing nets.
Slide 17 - Diapositive
By-catch by commercial fishing Sea turtles often get caught in commercial fishing nets. If the sea turtle becomes trapped and can’t get to the surface to breather, the sea turtle will drown.
Hundreds of thousands of sea turtles die each year in commercial fishing nets.
Female turtles use the same beach to nest on where they were born.
International laws regulate fishing.
Entangled in abandoned, lost or discarded fishing gear.
Slide 18 - Diapositive
Entanglement in fishing gear Commercial fishing nets abandoned, lost or dumped over board from fishing vessels are also dangerous for sea turtles and other species.
They float in the ocean like death traps waiting to catch unsuspecting marine life. They are referred to as ghost nets.
For more information on this topic see the Lesson: Abandoned, Lost and Discarded fishing gear.
Female turtles use the same beach to nest on where they were born.
International laws regulate fishing.
Coastal development impacting nesting sea turtles.
Slide 19 - Diapositive
Coastal development impacting nesting sea turtles
In many nesting areas the beaches have been developed for recreation and tourism. People don’t take any notice of the sea turtles and will drive cars on beaches, crushing the eggs in their nests or letting their dogs run loose on the beaches attacking the nesting sea turtles.
Sea turtles are also losing their feeding grounds close to shore. In many areas, the sea beds are being destroyed by shipping and chemicals used in farming and industries, which are washing into the ocean.
Female turtles use the same beach to nest on where they were born.
International laws regulate fishing.
Oil spills.
Slide 20 - Diapositive
Oil spills Oil spills leave marine wildlife coated in oil and unable to breath. The dispersants used to break up oil on the surface causes the oil to drop to the ocean floor, coating it in a sludge.
This coating affects the health of the seafloor, killing sea grasses and any other life. Sea grass is part of the food chain for sea turtles.
CLIMATE CHANGE
Rising water levels and ocean temperatures impact nesting beaches. ➢ With higher tides, there is a risk of sea turtle nests being flooded with water and the eggs not surviving. ➢ The change in temperature impacts the sex of the hatchlings, the cooler temperature results in more male hatchlings, warmer temperatures more females.
Slide 21 - Diapositive
Climate change Rising water levels (and tides) and warming air and ocean temperatures are impacting sea turtle nesting beaches. There are two impacts
With higher tides, there is a risk of sea turtle nests being flooded with water and the eggs not surviving.
The change in temperature impacts the sex of the hatchlings, the cooler temperature results in more male hatchlings, warmer temperatures more females.
Scientists are finding with the warmer temperature most hatchlings are female. This creates a further issue for already endangered species.
Taking eggs takes away the
next generation of sea turtles.
Plastic pollution - over 12 million tonnes of trash enters the ocean each year.
Slide 22 - Diapositive
Plastic pollution Plastic pollution is an issue for all marine wildlife.
Each year over 12 million tonnes of trash finds its way into the ocean, adding to pollution already there.
What do you think happens if turtles find rubbish in the ocean?
Turtles can’t distinguish the difference between rubbish and food, and when they do it may be too late and they may already have swallowed it, or been entangled in it.
.
INTERNATIONAL LAW
& CITES
CITES - Convention on International Trade of Endangered Species, requires that countries who have signed up to CITES must prohibit any trade in sea turtles or anything made from them.
Individual countries may also have their own laws to protect sea turtles.
Slide 23 - Diapositive
Protecting sea turtles There are International laws in place that state it is illegal to carry sea turtle parts or products between countries, but most items are sold locally.
Endangered species, like sea turtles, are also protected under CITES (Convention on International Trade of Endangered Species).
Countries who have signed up to CITES must prohibit any trade in sea turtles or anything made from them.
Protecting sea turtles around the world.
Protecting sea turtles around the world.
Slide 24 - Diapositive
Protecting sea turtles Conservation groups like Sea Shepherd and local activists patrol beaches to protect nesting sea turtles from poachers.
In high risk areas sea turtle eggs are removed from the nest and are taken to hatcheries, where they can be kept safe until they hatch and will have a chance to make it to the ocean, as a young turtle.
How do you think you can help protect sea turtles?
Slide 25 - Carte mentale
How do you think you can help protect sea turtles Ask students to answer the following question using www.LessonUp.app or discuss in the classroom.
“How do you think you can help protect sea turtles?”
How can you help
protect sea turtles?
Help stop the use of turtle eggs and meat.
Never purchase products made from turtle shells.
Do not disturb nesting turtles, nests or hatchlings
Remove all your beach equipment when you leave.
Be sure to knock down sandcastles before you leave or new hatchlings.
Slide 26 - Diapositive
Protecting sea turtles Ways to help protect sea turtles:
Help stop the use of turtle eggs and meat by spreading awareness about how endangered the species are.
Never purchase products made from turtle shells.
Do not disturb nesting turtles, nests or hatchlings.
If visiting nesting beaches ensure you remove your beach equipment. Eg. Beach chairs, umbrellas and children’s toys, so turtles can come ashore and hatchlings find their way to the ocean.
Be sure to knock down sandcastles before you leave the beach because they become obstacles for nesting turtles or new hatchlings.
Protecting sea turtles around the world.
Reducing plastic pollution - how can you help?
Slide 27 - Diapositive
Reduce plastic pollution Help reduce plastic pollution to protect sea turtles. Participate in beach clean-ups.
Discuss ways to reduce plastic pollution.
Name five issues impacting on sea turtles?
Slide 28 - Question ouverte
Ask students to answer via www.LessonUp.app or discuss in classroom.
“Name 5 issues impacting sea turtles?”
Write down three things you have learned?
Slide 29 - Question ouverte
What did you learn? Ask students to answer the following question using www.LessonUp.app or discuss in the classroom.
“Write down three things you have learned?”
Write down one thing you didn't understand?
Slide 30 - Question ouverte
What don’t you understand? Ask students to answer the following question using www.LessonUp.app or discuss in the classroom.
“Write down one thing you didn’t understand?”
Slide 31 - Diapositive
Sea Shepherd Case Studies cover a number of Sea Shepherd campaigns and show video of some of our work to protect sea turtles. These can be used to enhance the learning experience from these lessons.