Beavers reintroduced to Scotland and England: What's happening now?

The Eurasian beaver (Castor fiber) became extinct in Britain in the 16th century due to hunting for its pelt, meat and scent glands. Beavers bring numerous benefits to their local environments and so there have been talks and many debates in various places about the potential for reintroducing them. They are often referred to as ecosystem engineers. By modifying their habitats through the coppicing of trees and shrubs, the digging of canal systems and damming of water courses, beavers create and maintain diverse wetlands that bring huge benefits to other species including otters, water voles, birds, invertebrates and fish. This kind of habitat restoration can be extremely costly to achieve by artificial means.

Beaver dams also play a role in slowing water run-off during periods of flooding and can help sustain flows during periods of low water. Beaver inhabited landscapes have been linked to counteracting pollution from human activities. The open nature of beaver generated environments commonly results in a vigorous community of vascular plants. Where agricultural nitrates leak into these environments they are rapidly absorbed.  It has been estimated from studies in Bavaria that up to 28kg of soluble nitrates can be captured through the annual habitat creation activity of a single beaver.

Scotland

In 2009, wild beavers were first reintroduced into Knapdale Forest in Argyll, Scotland after being extinct in the UK for over 400 years. The trial is a partnership project between the Scottish Wildlife Trust, The Royal Zoological Society of Scotland and the Forestry Commission. It is the first official project of its kind in Britain and was followed by a five year study to explore how beavers enhance and restore natural environments. 

Breeding beavers in Scotland.
Photo: RZS Scotland.

England

A colony of wild beavers were spotted living on the River Otter, Devon, in February 2014. The origin of the population is unknown, It is presumed to be the result of an escape or unsanctioned deliberate release. There is now evidence of beaver activity on the River Otter from Honiton to Budleigh Salterton, a distance of around 12 miles. A breeding pair with young was filmed in 2014 on land south of Ottery St Mary. It is estimated that there are at least nine beavers on the river, including one confirmed breeding group. 

Beaver in the Devon trial area.
Photo: David Plummer.

In January 2015, Natural England granted Devon Wildlife Trust a licence that allowed the beavers to remain on the river, as part of a pilot experiment and five year monitoring. The River Otter Beaver Trial will work with international experts to record and evaluate the impact of the animals. At the conclusion of the project in 2020 the River Otter Beaver Trial will present Natural England with its evidence. Using this information a decision will be made on the future of the beavers on the river.

What's happening now?

Following the scientific work undertaken on the Scottish Beaver Trial, Scottish Natural Heritage have since released their report ‘Beavers in Scotland’. The report uses 20 years of work on beavers in Scotland, as well as experience from elsewhere in Europe and North America. It provides a summary of existing knowledge and offers four future beaver scenarios for Scottish Ministers to consider. The Trial is now in a holding period whilst awaiting the decision from the Scottish Government about the future for the beavers, but there is no news as of yet.

The beaver trial in England is ongoing and the surveying and monitoring is set to conclude in 2020, ready for the government to evaluate the evidence and come to a decision on the beavers remaining at the site in Devon, as well as potentially increasing trials to other locations.

It will be very interesting to see what they decide. The trials have been successful and the benefits of having beavers living naturally is proven. As well as this, the UK has obligations under the EU’s Habitats Directive to consider reintroductions of extinct native species, so reintroducing beavers to certain areas could also assist with this. 


For more information and to keep up to date with the beaver trials you can visit:
http://www.ScottishBeavers.org.uk
http://www.DevonWildlifeTrust.org/devons-wild-beavers
http://BeaversInEngland.com

The Most Trafficked Mammal in the World - Pangolins.

Pangolins are the only mammal in the world that are covered with scales. They are often referred to as scaly anteaters as they also eat ants and termites with a long sticky tongue.

They are a fascinating species and today (20th February 2016) is World Pangolin Day, which is a great opportunity to raise awareness about this unique creature and the current threats they face.

There are eight different species of pangolin which are found across Asia and Africa.

African pangolins:

• Cape or Temminck’s Ground pangolin (Smutsia temminckii) – Vulnerable

Photo by Nigel J. Dennis

• White-bellied or Tree pangolin (Phataginus tricuspis) – Vulnerable

Photo: APWG, Zoological Society of London.

• Giant Ground pangolin (Smutsia gigantea) – Vulnerable

• Black-bellied or Long-tailed pangolin  (Phataginus tetradactyla) – Vulnerable

Photo by Rod Cassidy.

Asian pangolins:

• Chinese pangolin (Manis pentadactyla) – Critically Endangered

• Sunda pangolin (Manis javanica) – Critically Endangered

• Indian pangolin (Manis crassicaudata) – Endangered

Photo by Rajesh Kumar Mohapatra.

•  Philippine pangolin (Manis culionensis) – Endangered

Photo by Roger Dolorosa.

Pangolins are under threat from the illegal trade in their scales and flesh. They are one of the most trafficked mammals in Asia but increasingly in Africa. As you can see by the above list the effect the illegal trade is having on the Asian populations is very significant, with all species listed as endangered. Although the African species are currently listed as vulnerable, the problem is spreading and increasingly impacting these species also.

The pangolin got its common name from the Malay word 'pengguling', meaning 'rolling up', in reference to their defence mechanism of rolling into a tight ball when threatened. Unfortunately, this makes it even easier for them to be captured and smuggled, as hunters can simply pick them up.

Nobody knows for sure exactly how long they live. It is presumed that pangolins have an estimated lifespan of twenty years in the wild, since the oldest recorded pangolin lived for 19 years in captivity. They are very rarely found in zoos as time spent in captivity tends to bring about stress and malnutrition, leading to early death. As such, it is unknown how long a pangolin can actually live for making this interesting creature even more mysterious.

For more information you can watch the short video below and visit:
http://pangolins.org or http://savepangolins.org.

Attracting Birds to Your Garden: Which Box is Best?

This week is National Nest Box Week. Here i've written a handy blog post on the types and variations of available nest boxes and preferences of different species you may be looking to either attract, or benefit birds you already see in your garden.

Research has found that there are over 60 UK bird species that have used or benefitted from nestboxes. The most important details are the type of box and its location.

A key point to remember that is true for all species, is that the perch is not necessary! Many nestboxes you might find in shops come with perches attached that are largely for decorative purposes but they can actually be detrimental as predators use the perches to gain access to birds inside. Birds do not need perches to get inside or out of a nest box so always remove it if possible.

Blue tits using the most common style of nest box,
and showing how there is no need for a perch.
(Photo: CJ Wildbirdfoods Ltd)

Nestboxes for Small Birds.

These sorts of birds will be fine with the common style of nestbox (see picture, right) with 4 walls with a roof and a hole for entry and exit. The average specifications which will be suitable are 22 x 20 x 16 cm.

A 25mm sized hole is best suited for blue tits, coal tits and marsh tits.

A 28mm sized hole will attract pied flycatchers, great tits and tree sparrows.

A 32mm sized hole will suit nuthatches and house sparrows.

If you want to create or buy a nestbox for starlings, then you can use the same design as above but it will need a 45mm hole, with dimensions of around 31.5 x 18.5 x 18 cm.

The nestboxes should be positioned 2 to 4 metres up a wall or tree in an area avoiding strong sunlight where possible. It is important for all nestboxes that it can be opened somehow either through a removable roof or hatch, for end of season cleaning. Used nestboxes should be removed and cleaned in the autumn once the birds have stopped using the box to clear any fleas or parasites. Use boiling water only, never insecticides or other powders/chemicals.

If you can only get a nestbox with an entrance hole larger than you would like, you can always fix a plate onto it in order to reduce the size as shown below. These will prevent larger birds from using your nestbox as well as further protect it from predators, with the steel stopping the entrance from being clawed away at or damaged to gain access.

Photo: RSPB

Open-fronted boxes.

For attracting and supporting wrens, robins, pied wagtails and spotted flycatchers you should use an open fronted box placed low down, below 2m and well hidden in vegetatation. Ideal specifications for the box would be around 28 x 23 x 17 cm.

Woodpeckers also use open fronted boxes but they should be placed 3 to 5m high preferably on a tree trunk in an open area.

Open-fronted boxes like these are ideal for attracting birds such as robins and wrens.
Photos: RSPB

Speciality

A nestbox for swifts, sold by the RSPB.

If you have swifts, swallows or house martins then you will need a different design for your nest box if it is outside.

These need to be high up, at least 5 metres out of direct sunlight. It should ideally be positioned under the eaves of your house, outhouse or other building. The location must be undisturbed by people or potential predators and have an unobstructed airspace infront of the nestbox, which will allow the birds to fly in directly.

There are terracotta nest cups you can buy for house martins and swallows that are designed to copy the natural design of the nests they build themselves. Whilst staying at Blakeney I took a picture (below) of a swallow nest that had been built outside above the window to my room. Here you can see the similarities of these boxes to the real thing. If you do decide to invest in one of these, don't be disheartened if the birds continue to create their own nests nearby, it can take a couple of years of swallows and house martins returning to the property before they will use the nest cups.

Swallows I photographed in a natural nest and the shop-bought nests you can buy.

Nestboxes for Large Birds.

You might be surprised to know that birds such as owls are frequent users of nestboxes, for example, it is estimated that up to half of the barn owl population in the UK use manmade nestboxes. So if you are lucky enough to have owls and kestrels nearby, a properly positioned nest box can definitely help these birds.

Similar to the nest cups, it can take years before these boxes will be used properly, so give it time.

The minimum height these nestboxes should be positioned is 5m, you preferably want to fit them up a tree that has is not cluttered, with clear visibility and has clear flight path to it. It should be faced away from the main wind direction. The size of the nestbox will vary depending on which species you want to encourage.

A good kestrel box should be: Width - 28.5cm, Depth - 52cm, Height - 34cm.

Tawny owls nest in smaller cavities than other owls so a thinner but higher design is ideal. Specs should be around Width - 22cm, Depth - 41.5cm, Height - 77cm for a good quality tawny owl box.

A barn owl requires a larger nest with more space below compared to a tawny owl. The minimum size should be no less than Width - 57cm, Depth 49cm, Height - 67cm.

If you live in an area with little owls, then you may want to put out a smaller box. They require a box with a corridor and dark nesting area below, so unless you are fairly DIY savvy, I would recommend buying a premade certified box from a place such as The Barn Owl Trust, but it also has a great guide on how to create your own box if you fancy giving it a go.

Various nestboxes for large birds.

For more information, nestboxes available to buy as well as guides on making them yourself, there is great advice on the RSPB website.

I'll be putting my own box out this week and will post updates on what I attract to the garden. If you are putting out a nestbox this week, i'd love to see your box and hear about what you get visiting you, so feel free to write to me or tweet me any pictures and stories.

Green Mumbles Top 10 Critically Endangered Mammals Video.

I have decided to make videos alongside this blog under a YouTube channel of the same name as another side project.

The first I have made is a top 10 list of critically endangered mammals. Every species I have included in the list I picked due to their especially low population sizes and also due to them being relatively unknown compared to the "big names", such as the Javan Rhino and Amur Leopard that always pop up in similar lists.

It includes the Vancouver Island Marmot (Marmota vancouverensis), with an estimated population size of 250 - 300,

(The Vancouver Island Marmot Recovery Foundation)

the Tamaraw (Bubalus mindorensis), with an estimated population size of less than 250,

(Photo by Daniel Heuclin)

and the tiny Pygmy Hog (Porcula salvania), that also has an estimated population of less than 250.

(Durrell Wildlife Conservation Trust)

These species are all particularly interesting and are important to conserve. For example, genetic research has shown that the Pygmy Hog is the sole species in the genus Porcula meaning that if it died out, the entire taxonomic category would go extinct with it.

The Tamaraw is endemic to the island of Mindoro in the Phillipines and is the only bovine species native to the country giving it high national significance.

The Vancouver Island Marmot is one of Canada's most endangered animals and is specifically only native to, you guessed it, Vancouver Island in British Columbia. It is one of the largest members of the squirrel family and has a very successful captive breeding programme, which is likely (and hopefully) going to create a success story for this cute Canadian critter.

The list contains other interesting species such as these, many of which you may never have heard of. I hope you enjoy my first attempt at a wildlife related video and i'll be making the next one soon, so watch this space!

The Critically Endangered Mountain Chicken.

A "Mountain Chicken".

Contrary to the name, the Mountain Chicken isn't actually a large alpine bird. It is infact, a species of frog found only in the Caribbean islands of Dominica and Montserrat. The name "Mountain Chicken" is actually only the local name that the people have given to the frog due to its very large size and the fact that it is eaten for food.

The common name for this species is the Giant Ditch Frog (Leptodactylus fallax) and it is currently highly under threat having declined by up to 90% in the last ten years and is listed as critically endangered as a result.

The real Mountain Chicken, showing just how large this species is!

The actual population figures for this species do not even reach 100. It is estimated that there are only 44 wild individuals left on the Dominica islands and 3 on Montserrat.

On Dominica, the population was once healthy and stable and the frog was a popular food source for local people, being particularly favoured for its legs which are cooked in traditional West Indian dishes. The Mountain Chicken actually used to be the country's national dish, but was replaced in 2013 after this became problematic considering it's conservation status. Prior to this, annual harvests were thought to be taking between 8,000 and 36,000 animals before the ban on hunting was introduced, but the population had already been highly damaged. The frog is particularly vulnerable as it has a small brood size, which limits its ability to recover from heavy losses. Its large size, loud calls and attraction to open spaces also made it an easy target for hunters.

 

Mountain Chicken's aren't very good at hiding or keeping out of sight.
Photo by Jenny Spencer.

This combined with habitat loss and introduced invasive predators have also had an effect on the population. But the most recent threat now comes from a familiar amphibian foe which has decimated frog populations worldwide... Chytrid Fungus.

Chytridiomycosis is the disease that occurs when an amphibian is infected with large amounts of the chytrid fungus "Bd". There are numerous varieties of chytrid fungus but the "Bd" fungus is the most problematic as evidence suggests that it is capable of infecting the majority of the world's 6000 amphibian species. The fungus causes the skin to become thicker and tougher. This is a huge issue for amphibians as rather than drinking water and gaining vital nutrients through their mouth, they absorb it all through their skin.

Global cases of Bd in 2009. (from Fisher, et al., 2009)

The fungus is highly infectious and spreads through habitats largely via water and moist or wet materials, being able to persist in the moist environments that amphibians favour for several months. The fungus was spread to Dominica and Montserrat in 2002 and quickly made its way around the islands infecting the Mountain Chicken population. 

Chytridiomycosis has quickly become the worst disease and one of the biggest threats to amphibians that the world has ever known. Steps being taken to combat it include the reduction in shipping of amphibians around the world and much stricter screening and quarantine measures. Fortunatly, scientists are on the case, and last year saw the first ever successful elimination of chytrid fungus in a wild amphibian population. This study is a significant step forward in potentially halting the damage of this disease but there is still a lot more research ongoing and lots left to do.

The paper can be found in Biology Letters here.

For more information on Mountain Chicken conservation you can visit: http://www.mountainchicken.org

https://www.zsl.org/conservation/regions/americas/mountain-chicken-frog-conservation

World Wetlands Day: All About Wetlands

Wetlands are an extremely important environmental asset, having huge biodiversity compared to other areas of the world. Throughout history they have been integral to human survival and development. They exist in every country and in every climatic zone, from the polar regions to the tropics.

Swamps: An important wetland habitat.

Wetlands are dynamic and variable. They can be freshwater, brackish or saline, seasonal or permanent, inland, coastal, natural or man-made.

Up to 42 types different of wetlands have been formally identified, some of these include:

• Lakes 
• Rivers
• Mangroves
• Swamps and marshes 
• Floodplains
• Bogs and fens
• Coral reefs

Wetlands are vulnerable to over-exploitation due to their abundance of water and natural resources such as fish. They are often targeted for drainage and conversion due to development pressures. The rate of loss and deterioration of wetlands is accelerating in all regions of the world. It is expected that the pressure on wetlands will intensify in the coming years due to increasing demand for land and water.

The Ramsar Convention was signed in 1971 and is the international treaty dedicated to the conservation and sustainable use of wetlands. It recognises the fundamental ecological functions of wetlands and their scientific, economic and recreational values.

 

 
Ecosystem Services: The Value of Wetlands to People

Wetlands are highly efficient at absorbing chemicals, filtering pollutants and sediments, breaking down suspended solids and neutralising harmful bacteria. As well as being the most biologically diverse ecosystems on Earth, they provide valuable ecosystem services to people throughout the world.

The most significant social and economic benefit that wetlands provide is flood control. Peatlands and wet grasslands can act like sponges, absorbing rainfall and controlling the flow into rivers and streams.

Coastal wetlands such as reefs, saltmarshes and mangroves act as frontline defences against natural disasters such as hurricanes and tsunamis. The roots of wetland plants bind the shoreline together, providing a strong barrier that slows down storm surges and tidal waves, thereby reducing their height and destructive power.

Wetlands are natural filtering systems, removing nutrients through effective wetland plants. They remove pollutants such as phosphorous, heavy metals and toxins which get trapped in the sediments. One of their key roles involves filtering Nitrogen in water and transforming it into harmless nitrogen gas. 

Image displaying wetland nitrogren removal.

Wetlands are often viewed as wasteland, and more than 64% of wetlands worldwide have disappeared since 1900. They are extremely important for the benefits and ecosystem services they provide. Wetlands are also valuable habitats for numerous species such as migratory birds, and are key in the conservation of these animals.

Tomorrow is World Wetlands Day, a great opportunity to share information and spread awareness about the importance of wetlands. This is especially important as few people realise just how vital they are in our every day life and how much we depend on their functions.

Wetlands International   -    RAMSAR   -   World Wetlands Day