How light affects wildlife.
Animals need darkness to stay happy!
What is the difference between these 2 pictures? (Light pollution!)
In a natural place without people, the sky is naturally lit up with stars. But when people move there, they change the night. For example in this picture. On the left is with the outdoor lights on. On the right is what the sky looks like with the outdoor lights off. Pretty amazing!
Light pollution is simply lighting that is unnecessary, inefficient, overly bright, and not shielded.
Light pollution affects our health, our view of the starry night sky, and the health of wildlife.
As a class create a list of things animals need to survive. Refer to lessons the children have already been taught about food, water, shelter and space. Many species also need darkness for purposes of reproduction, hunting, sleep and protection.
Brainstorm what animals could need darkness to survive where you live.
Animals that benefit from darkness at Great Basin National Park are bats, hundreds of songbirds, mountain lion, owls, fox, and even insects.
Explain a bit about the activity students will soon participate in.
They will be pretending to be 1 of the 3 animals on the next few slides. They will crawl, fly, run, dance etc. over to a cone set a distance from them. Under 1 cone are the things that animal needs during the night, the other 2 cones have cities under them. These cities interfere with animals, so they don’t get the food, water, shelter and/or space that they need. They will be learning about how the light pollution is specifically affecting sea turtles, birds and mountain lions.
You might want to play one of the baby sea turtle videos to better help students understand how the city lights affect them. Ask student what they already know about sea turtles.
Possible points of discussion:
-When its time for the females to lay eggs, they return to the same nesting ground where they were born.
-Their eggs look like Ping-Pong balls.
-They lay eggs at night and then 70-120 days later the eggs hatch during the cover of the night.
-Baby sea turtles have 4 hours to get from their nest to the ocean.
-They can hold their breath underwater for up to 5 hours.
-Some species can grow to weigh up to 2,000 pounds.
Introduce the scenario where light pollution might harm these sea creatures.
“You will pretend you're a baby sea turtle. You follow light, such as the moon, to make it safely to the ocean. But there is a city nearby with lots of bright lights. How do you know which way to go?”
Ask students what they know about birds.
Possible discussion topics:
-20% of bird species migrate long distances every year.
-There are 10,000 different species of bird worldwide.
-Birds eat seeds, berries, fruits, insects, dead animals, fish and plants.
-They have hollow bones to help them fly.
Introduce the bird scenario.
“You will pretend to be a kind of bird. Every year the cold of winter comes and there is much less food. You decide to migrate south with other birds. Usually you use the stars to navigate to where you are going but you are flying over a big city and can not see the stars. You get really confused. What might happen to you if you can not find your way?”
Ask your students what they know about mountain lions.
Possible discussion points:
-They are nocturnal (sleep during the day and are active at night). They need the darkness to hide as they stalk their prey.
-They are around 7-8 feet long and 2-3 feet tall.
-They mostly eat deer but sometimes eat raccoons, birds and small mammals.
-They do not roar like a lion but make calls like human screams.
-Kittens have black spots until they are about 6 months old.
“You will pretend you're a mountain lion. You’ve been sleeping all day and finally its night. You’re very hungry! After looking for an animal to eat, you spot a deer in the distance but it’s under a bright street light. What might happen as you try to attack?”
Ways animals need darkness to survive…
-Signals from stars that it’s time to migrate
-Migration routes- knowing where to fly
-Foraging or hunting- darkness creates cover for both predators and prey, many animals are nocturnal, darkness is their preferred time of activity
-Reproduction- darkness hides babies. Following the light can lead infants to survival (sea turtles)
-Safety-Most animals use darkness for safety whether they are predators or prey
There are many ways we can help our animal friends!
-Turn off your outdoor lights that don’t need to be on.
-Aim outdoor lights at the ground, don’t light up the sky!
-Teach your family and friends about the importance of darkness.
