Category Plants & Animals

Why are animals in danger?

Animals in Danger 
Hundreds of years ago, thousands of birds called dodos lived on the earth. But people overhunted them for food and introduced new animal enemies to their habitats. Now there are no dodos. Today, the numbers of polar bears, rhinoceroses, tigers, and many other animals are going down. These animals are in danger. Why? 
• Their homes are being destroyed. 
• People hunt them for their fur, horns, skins, and meat. Some are hunted for sale as pets and some because people think they are pests. 
• Pollution kills them. 
• Growing numbers of people crowd out animals and use up all the land and food. 
• People introduce new animals to a habitat, upsetting the balance of nature. 
Unless people work hard to save them, many other animals will become extinct like the dodo. 

Picture Credit : Google

What do we mean by food chain?

Food Chain

A field of green grass waves in the wind. A furry rabbit hops by and nibbles the grass. As the rabbit scurries around, an owl perches overhead. The owl swoops down, grabs the rabbit, and flies away to eat it. When it has eaten its fill, the owl leaves part of the rabbit’s body in another field of grass. The rabbit’s body feeds the soil.

It may seem cruel that animals kill and eat one another. But this is just one way in which wild creatures help each other and keep nature in balance. The grass, the rabbit and the owl are part of an important system in nature called a food chain.

All food chains begin with sunlight. Sunlight provides food for plants. Plants are the primary producers in a food chain. They use sunlight, water, and air to produce food to live and grow.

Animals that eat plants are another link in the food chain. They are consumers. Animals that eat the plant-eating animals are also consumers. The rabbit and the owl are consumers.

Tiny living things called decomposers are also part of the food chain. They break down dead plants and animals into parts. These parts nourish the soil in which the plants grow.

Picture Credit : Google

What is the seasonal movement of animals?

Animals on the Move

When the cold days of winter come, many animals find it hard to find food. So they fly, march, scamper, or swim to warmer places. When spring comes, they fly, march, scamper, and swim back. This movement from place to place as the seasons change is called migration.

Barn swallows, monarch butterflies, ladybirds, caribou, whales, salmon, and lemmings are just a few of the animals that migrate.

When birds migrate, they often fly great distances. Sometimes they cross oceans and continents. In spring, they migrate back. Sometimes they return to the same nests they used the summer before.

In winter, caribou leave their summer home in northern North America and begin dangerous journey southwards in large herds. The following spring they journey northwards again.

Lemmings are small mammals that live in northern Europe. They migrate sometimes, too. When there is a lot of food, lemmings have many young. When the food runs out, they migrate. Sometimes they travel along roads and through towns looking for food.

Picture Credit : Google

What is winter sleep in animals?

Sleeping Through Winter

Every autumn, a woodchuck eats large amounts of food, curls up into a ball, and goes to sleep in its underground home. But the woodchuck’s sleep isn’t like your sleep. The woodchuck’s heart and breathing slow down and nearly stop. Its body changes. Most of the time, the woodchuck’s body is warm because it is a warm-blooded animal. But the woodchuck’s body grows cold before it goes into its long winter sleep. As it sleeps, its body lives off the energy from the extra food it ate in autumn.

The woodchuck’s sleep is called hibernation. Ground squirrels, bats, hamsters, hedgehogs, and other warm-blooded animals also hibernate.

Snakes, turtles, frogs, and toads hibernate in a different way. A snake is cold-blooded. Its body is just as warm or as cold as the air around it. So when the weather grows colder, a snake’s body grows colder. The snake tries to get warm by crawling into a hole. But as the weather becomes colder, the snake’s body becomes cold and stiff. Its heart and breathing nearly stop.

When spring comes, the woodchucks and other warm-blooded animals wake up. The snakes warm up, too, and crawl out of their holes. The world is alive again!

Picture Credit : Google

What are seagrass meadows?

We all know what a meadow is. But most of us wouldn’t know they exist on the seafloor too. Seagrass meadows are among the world’s least known ecosystems. Yet these underwater gardens are crucial to our survival – they are among the most important carbon reservoirs on the planet

Seagrass is a flowering aquatic plant closely related to the flowering plants on land. Seagrasses have long green, grass-like leaves, and are found in shallow salty and brackish waters in many parts of the world

Seagrass meadows support a wide range of marine species such as fish, turtle and dugong. They help prevent beach erosion and mitigate the impact of destructive storm surges. They absorb CO2 and exude oxygen. They also clean the ocean by soaking up polluting nutrients and improve water quality. Recently, scientists have found that certain species of seagrass also capture plastic debris.

What are Neptune balls?

Posidonia oceanica is a type of seagrass found in the Mediterranean waters. When blades of P. oceanica fall or break off their fibres can form tangled masses in the shape of a rugby ball by the swirl of ocean currents. Called Neptune balls, these balls look like brown clumps of steel wool. And researchers have found that these Neptune balls, as they fomu have a knack for trapping small fragments of plastic and then wash ashore during atoms.

By analysing loose leaves and Neptune balls on four Spanish beaches, researchers found plastic pellets, microbeads and polyester fibres from clothes entangled in half of them. Up to 613 and 1,470 items per kg were found in loose leaves and Neptune balls, respectively.

Scientists who were part of this study estimate that the seagrass balls may collect up to 867 million bits of plastic in the Mediterranean annually.

And that’s one more reason to save the seagrass ecosystem from destruction from habitat loss, pollution, coastal construction and overfishing.

 

Picture Credit : Google

How do animals help each other?

Animal Partners

Hungry crocodiles usually try to eat birds that come near them. But one kind of bird can walk among crocodiles safely. In fact, this bird can lay its eggs in crocodile nests!

A bird called the water dikkop eats insects that disturb crocodiles. The bird gets an easy meal and the crocodile becomes more comfortable. So the birds are really helping the crocodiles. Maybe that’s why the crocodiles don’t harm them.

Little fish called wrasses help many other bigger fish. Tiny worms often fasten themselves to a fish and make sores on its body. When this happens, the fish goes to a coral reef where a wrasse lives. The little wrasse hunts all over the fish’s body and eats the worms.

A European fish called a bitterling teams up with certain freshwater clams. The female bitterling lays her eggs in the clam. When the baby fish leave the shell, clam larvae are buried in their skin. After the clam larvae have grown a bit, they leave the fish and sink to the bottom of the pond or river. The clam provides a safe place for the fish to lay its eggs, and the fish helps spread baby clams along the pond bottom.

The water dikkop, the wrasse, and the bitterling all get something from the animals they help. Some get food as a reward for getting rid of annoying pests. Others help each other reproduce.