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

Animals 26-30 in our '50 incredible animals' series

Hello, Welcome back. We're very sorry for missing last week's animals. We've all had a busy time with school work! 26. Blue glaucus Also known as the blue dragon, the blue glaucus is a type of sea slug. They are small, rarely growing longer than 3cm long. Their favourite food is probably the most bizarre thing about them, Portuguese man o' war. Now, for those of you who don't already know, the Portuguese man o' war is one of the most dangerous jellyfish in the world! Different sites have different opinions, but almost all agree that blue glaucus do not hunt the Portuguese man o' war, instead they feed on dead ones or nibble away at living one! But that's still rather impressive. 27. Shoebill Shoebills are very patient and able to stay still for hours. That's how they hunt. When a lungfish comes up for air, they often don't notice the shoebill standing there until it's too late. Shoebill...

Maldives - the direct impacts of climate change

Welcome back, Today we’re looking at the direct impacts of the climate crisis . The main reason why people don’t believe in climate change is that they can’t see it with their own eyes. So, we’re going to have a look at the Maldives where the effects of climate change become more obvious with every passing year. Maldives The full name of the Maldives is The Republic of the Maldives. It is an independent country made up of about 1 200 islands in the North Indian Ocean. The northernmost island is situated 370 miles away from the mainland (India). The islands are actually the tips of an ancient volcanic mountain range that is now almost completely submerged. In fact, the highest point is 1.8m-2.4m above sea level with the average elevation being 1m above sea level. The islands have a large tourism industry, due to the stunning nature found on and around the islands. 500 000 - 1 500 000 tourists visit the islands each year. This is mainly 'nature to...

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 2021 Factfile - a bit of news from the past month and more!

Hi Everyone! Welcome to the first monthly fact file! We are going to share a news article from last month as well as animals and more! News You might have heard that the UK has authorised the use of a pesticide harmful to bees. It has been authorised for use on sugar beet with their excuse being to do with the virus yellows disease. But bees are in serious decline and this is not going to help. It is authorised for emergency use and only in specific conditions but, in our eyes, that doesn't make it okay. Farmers need bees to pollinate crops and now they are killing them with a horrible pesticide. What do you think? We would love your opinions below! For more information on bees in our honey bee post click here . We have also found an article about some Indonesian monkeys from the island of Bali who steal anything expensive, that tourists have because they know they will get a reward! They know which items have the most value and wi...

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...

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...

Pollination

Hello everyone, Today we're talking about pollination and its importance in the world's ecosystems. First a bit of basic plant biology. To reproduce most plants do have a differentiation into male and female, but not in the same way that we see in mammals. Both male and female reproductive organs can be found on the same plant, although not in the same place. Male gametes are produced in the stamens and are then found in pollen. On the other hand, female reproductive organs are called pistils and egg cells are found in the ovule (normally in the flower heads). Pollination describes the process of transporting the pollen to the egg cells, making it an essential part of the reproduction of plants. Nearly all seed plants worldwide require pollination to reproduce. Cone bearing trees also need pollination. Pollination is almost always assisted by other organisms such as insects, birds and mammals to transport the pollen. In some species wind ...

2023 on Green World: the stats, our reflections & more || wrap up

Hi, Welcome back to Green World! This year has been amazing for our blog, so today we wanted to share some stats, personal reflections from each of the editors and some important information for 2024! 2023 in stats 52 posts 86 463 views most viewed post: Geothermal and Hydropower Energy in Iceland || Iceland Series (part 2) best posting month: August worst posting month: January 2610% increase in views compared to last year! How was it for us? Elsie: This year has been an incredible experience for me. I'm so grateful for all of your support and have loved writing weekly posts on topics that mean so much to me. My favourite post to write was National Parks post, it made me want to travel to all those amazing places. I've also found writing the energy comparison series really interesting because they required a lot of background knowledge and research and made me think more deeply about the complex topic of electricity production. I can't wait to see what 2024 brings us. Fr...

Green World

Search This Blog