Beavers and their dams: what effects do they have?

Hi everyone,

Today we're talking about beavers and their effects on the surrounding ecosystems and environments. 'Beaver' referres to two species in the genus Castor. They are found in North America, Europe and Asia and are the largest rodents in those places and the second largest rodents in the world. Beavers grow up to 80 cm long with a flat, paddle-shaped tail up to 45 cm. They have a small head, large incisor teeth and fur lined lips to avoid inhaling water while cutting and transporting branches underwater. They weigh 16-30kg and are nocturnal.

Beavers live in streams, rivers, marshes, ponds and lakes where they construct dams. These have earned them the title 'ecosystem engineers' but we'll talk about that later. The dams are constructed with branches, sticks and rocks. They create a calm pool with a higher water level on one side. Beavers make their homes (lodges) in these calm pools. Beaver dams are both have both positive and negative effects on the environment.

Probably the biggest problem with beaver dams is the flooding. The water that is held back by the dam has to go somewhere and it normally floods the surrounding landscape. This is where the name 'ecosystem engineers' comes from because they change the entire landscape by redirecting/expanding the rivers and streams and therefore drastically change the flora and fauna. This can cause severe damages to surrounding ecosystems and human infrastructure.

Beaver dams also interfere with migration of fish species such as salmon, as they block the rivers that these fish are trying to travel up/down. Also, methane producing microbes thrive in the sediment that forms around beaver dams. This is a big problem in regards to climate change. The water also has a severe lack of oxygen, causing many underwater plants die.

However, beaver dams have a lot of benefits. The flooding of the surrounding area creates wetlands which promote biodiversity. The beavers thin out trees while making their dams which prevents the domination by a single plant species and reduces the risk of forest fires. Different species of plants, animals and microorganisms thrive in the pools behind the dams. These pools also store carbon as the submerged wood decomposes a lot slower due to the lack of oxygen. The carbon stays locked in the wood for a long time leading to beaver meadows to be a large carbon store. The problem is that when the beavers leave the area or get killed, the dams eventually break and the wood is exposed to oxygen.

The dams reduce erosion, which is a big problem that waterways and coasts are facing at the moment. The dams also mean that sudden flooding is reduced. When floods of water come down a river, they can cause massive destruction but the beaver dams and surrounding wetland can catch the floods and lead to just a small slower increase of water further downstream.

We hope you found this post interesting. And who knows you may have beavers in your local area! In the UK, they have been reintroduced as a very cheap form of flood protection and water management.

Your Green World Blog Team💚

Sources:

https://www.britannica.com/animal/beaver

https://www.forestwildlife.org/how-do-beaver-dams-affect-the-environment/

https://www.science.org/content/article/what-role-do-beavers-play-climate-change

https://www.stir.ac.uk/news/2018/10/beavers-impact-on-biodiversity-revealed/

https://iopscience.iop.org/article/10.1088/1755-1315/201/1/012015/pdf

Images:

1: This image, owned by Michael Levine-Clark (on flickr.com) is liscensed under CC BY-NC-ND 2.0.
2: Beaver Dam in Winter, owned by Gerry Dincher (on flickr.com), is licensed under CC BY-SA 2.0.

3: This image, owned by Fred Moore (on flickr.com) is liscensed under CC BY-NC 2.0.

Comments

The life of ... an alcon blue butterfly

Hi everyone, Today we are going to be looking into the life of an alcon blue butterfly (Phengaris alcon). After mating, the females lay their eggs on marsh gentian, a blue-coloured wildflower. The eggs can only be laid on these flowers, as this is what the newly hatched caterpillars will eat. Although in some alp regions, they can also be found on willow gentians, a close relative of the marsh gentian. Once the caterpillars have hatched from the eggs, their main predator and danger are the ants that swarm below. But high on their plant homes, the caterpillars are safe. However, this isn't where the alcon blue caterpillars are going to stay forever. Eventually, they drop down to the ground using silk strings. With no protection, they are soon dragged off by the ants. The most amazing part is, the alcon blue caterpillars give off the same scent and chemicals as the ant larvae. So the ants take the caterpillars back to their brood chamber, wher...

August 2021 Factfile - some news, animals and a plant

Welcome to our August factfile, News Bad news :( Fires in and around Athens Athens has been under siege this month, but not by any army. The forests all around the capital and in other parts of Greece and Turkey have gone up in flames. Houses have been destroyed and thousands have been evacuated. The reason is, of course, climate change . “It’s been crazy over here. Between the extreme heat and the wildfires, it feels apocalyptic,” Eleni Myrivili wrote in an email on Thursday as the army was deployed to assist firefighters. “Ash is raining down on us here in Athens.” England's lake district in peril Lake District, a popular holiday resort in the north of England, is now eroding faster as a result of climate change and an increased amount of walkers due to the pandemic. Paths that were once two meters wide are now at least 12 meters wide on some walks. Also visitors tend to walk off the path, endangering local wildlife. With...

January Top Tips // 5 ways you can individually tackle climate change

Hi Everyone! This is the first of our new monthly posts for 2022! We will be sharing top tips every month, near the beginning, for things you can do during that month for the better. It's almost like a whole year of new year's resolutions (though let's hope they are achieved)! In these posts, we aren't just going to talk about climate change , of course, there will also be posts about animals , plants, habitats, plastic pollution and so much more! They will not be huge tips though, they won't demand too much of you (usually!). We need rebellions and people in the public eye spreading the word of course but we also need people like you, who can just do their bit. So, welcome to our top tips posts! We all know that we need to come together to fight the climate crisis, but we don't seem to be doing that right now. So here are our top tips for ways you can individually tackle climate change, even if this means simply spreading ...

Animals 31-35 in our '50 incredible animals' series

Hi Everyone! Welcome back to our blog, today we are sharing another 5 incredible animals. This is part of a series to celebrate our 50th blog post, all about unusual animals! Enjoy! 31. Pangolins These creatures are often mistaken for reptiles but they are in fact mammals. They are covered in scales and use them to defend themselves because similar to a hedgehog, they curl up into a ball. They eat ants, termites and larvae. They eat using their tongue, which is very long- sometimes even longer than their body! Sadly, Pangolins are in high demand as their meat is considered a delicacy their scales are used in traditional folk remedies, which means that there is an illegal trade. Luckily, there have been many initiatives put in place to help these animals by WWF and similar organisations. 32. Macropinna Microstoma This is a species of fish that live at about 600m below sea level. They hang nearly motionless in the water and have a very unusual...

Palm Oil

Hi everyone, Today we would like to share with you some information about palm oil. With all the focus on climate change and plastic pollution, not many people are acting against the use of palm oil. Workers First of all, the managers promise that the workers will have good money, but when they arrive, their passports are taken from them, therefore, meaning they are trapped. Soon they find out that they aren't paid as well as promised. They have to work long hours with no breaks, maternity leave or sick days. Some people have to spray pesticides with leaking cans and no safety gear, meaning they become ill but are still forced to work. Deforestation Many animals are losing their home because the trees are chopped down to make room for the palm trees. they are now facing extinction. Also, trees helped to slow down climate change, but without them, climate change speeds up. So this is a big problem. Help your planet! Image:...

Discussion || Should Everyone Switch To Electric Cars?

Hi Everyone! Thank you so much for joining me today, as I hop on the blog to discuss whether everyone switching to electric cars would really help the environment. In other words, should everyone switch to electric cars? This is the first part of a two-part series, discussing electric cars, so stay tuned for part two!! I would like to start this post by stating that I am by no means an expert. This is knowledge I have from my own experience, and from research I have done. If anything is incorrect please take it as it is and accept that this is a discussion and I am taking on board all opinions from reliable sources on this complex topic. Electric cars are a huge topic when it comes to sustainability and "saving our planet". There is no debating the fact that electric cars are better for the environment than diesel or petrol once they are on the road. But the production of them is often very polluting, with one study show...

Energy comparison: wind turbines

Hello, Finally, we are back with another energy comparison. Today we're looking at wind turbines. Wind power is a fast-growing renewable energy source. In the US, the wind power industry currently employs 120 000 people across all 50 states. It could grow to employ hundreds of thousands of people by 2050. 9% of the electricity in the US in 2021 came from wind turbines, that’s 136 000 megawatts. The wind power industry saves 329 million metric tons of carbon dioxide every year. General knowledge and categorisation We should probably start off by clarifying how wind turbines actually work and what types there are. I’m not going to give an in-depth description of how wind turbines work because I don’t want this post to turn into a physics lesson. To put it very simply, the wind turns the blades, which turns the rotor. The rotor then turns the generator, which converts the kinetic energy (movement) into electricity. There are obviously a lot more...

19.07.2020: Animal of the week: Honey Bees

Hi everyone, This week's animal is the honey bee. Enjoy! General Information An average honeybee hive is made up of one queen, hundreds of male drones and thousands of female workers. If the queen bee dies then a new queen is created. The workers select a young larva and feed it with a special food called ‘royal jelly’. The ‘royal jelly’ makes the larva grow into a fertile queen. Queens live for several years but the workers only live for five or six weeks. An average worker will make a twelfth of a tee spoon of honey during her entire life. Drones are turned out of the hive and left to die in Autumn. In the summer months, the queen bee is very busy, she can lay up to 2500 eggs in a single day. How they affect the world around them Honey bees are very important for flowers, fruit and vegetables. This comes from the fact that they are pollinators. They help the plants by transferring pollen between male and female parts, meaning the plants can g...

The life of ... a cicada

Hi everyone, We're back to talk about another animal. Cicadas ( Cicadoidea ) are invertebrates and are 1.9cm to 5.7cm in size. There are 3 000 species that can be divided into annual cicadas and periodical cicadas. Annual cicadas can be seen annually and are found worldwide whereas periodical cicadas only leave the ground every decade or two and are only found in North America with hotspots in the eastern and central areas of the United States. Most annual cicadas have a lifespan of about two to five years and periodical cicadas can live up to the age of 17. Female cicadas lay around 400 eggs split up over several places. They normally lay their eggs on twigs, branches or other vegetation. The eggs hatch after about six to ten weeks, now known as nymphs, and dig their way into the soil. The nymphs feed on the liquids found in plant roots. They fully develop underground, before molting their shells and coming to the surface, now fully deve...

Turning waste into valuables

Hi, So this post was requested on Twitter after our September Top Tips about recycling . Today we will be talking about how to turn complete waste into something reasonably valuable. This is basically a form of upcycling but to a more extreme level. 1. Ecobricks So, almost a year ago we did a post about ecobricks , but they are such a good example of turning waste into valuables that we decided to put it here anyway. Ecobricks are a building material made from plastic. The waste plastic is washed and then compacted into a clean plastic bottle (also waste). The bottle becomes very hard and durable. Multiple bottles can then be used as bricks and cemented together. The 'bricks' are strong and do not decompose. For more info, read our post where we go into more detail. 2. Metals Although this may seem like something not worth the time. When you separate the metals in waste (for example an old car), you can get usable metal out ...

Green World

Search This Blog