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Archives for March 2017

New ‘Tree Charter’ to protect people’s rights to the benefits of trees and woods

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More than 70 organisations with a combined membership of 20 million people launch 10 principles to bring trees and woods to the centre of UK society

Monday 27th March saw the launch of 10 guiding principles for the future of trees, woods and people, drawn from more than 50,000 stories submitted by members of the public. The principles reveal the role of trees in our lives, and are agreed by a coalition of more than 70 cross-sector UK organisations. These organisations are now united in calling for people across the UK to stand up for trees by signing the Tree Charter and helping to shape history.

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The principles will form the bedrock of the new ‘Charter for Trees, Woods and People’ to be launched in November 2017, which aims to secure a brighter future for the nation’s woods and trees, and to protect the rights of all people in the UK to access the many benefits they offer.

The creation of the Tree Charter is supported by a raft of famous names including:  Clive Anderson, Benjamin Zephaniah, John Humphrys, Chris Packham, Kevin McCloud, Gemma Cairney and Carenza Lewis, who have all helped to create animations to support the project principles.

At a time when England may have tipped into deforestation, with more trees being cut down than planted for the first time in 40 years, it is essential we act now as a nation to protect the future of trees and woods for people for generations to come.

From community woods across the UK, street trees in our cities, timber in our houses, to many ancient trees and woods with historical and cultural connections such as the Tolpuddle Martyrs tree2 – which saw the birth of trade unions – or Sherwood Forest linked to much folklore and history, trees and woods play an important part in our lives3, but more woods are under threat than ever before4.

Beccy Speight , Woodland Trust CEO said: “Today, our nation’s woods and trees are facing unprecedented pressures from development, pests and diseases and climate change. They risk being neglected, undervalued and forgotten.  Now is the time to create a new Tree Charter, which recognises the importance of trees in our society, celebrates their enormous contribution to our lives, and acts now so that future generations can benefit from them too.

“Our collective ambition is for a Tree Charter that puts trees back at the heart of our lives, communities and decision making – where they belong. The Tree Charter will provide guidance and inspiration to allow us all to appreciate, preserve and celebrate our trees and woods for what they do for us in so many different ways.”

Whereas the historic charter was signed by the King to grant rights to his subjects, the new Tree Charter will draw its strength from people power, with signatures from hundreds of thousands of people from across the UK.

Principle Theme                                               Principle Aim

  1. Nature Thriving habitats for diverse species
  2. Planting Planting for the future                                                                  
  3. Arts & Heritage Celebrating the cultural impacts of trees
  4. Utility & Livelihoods A thriving forestry sector that delivers for the UK
  5. Protection Better protection for important trees and woods
  6. Planning Enhancing new developments with trees
  7. Health & Wellbeing Understanding and using the natural health benefits of trees
  8. People & Access to trees Access to trees for everyone
  9. Coping with Threats Addressing threats  to woods and trees through good management
  10. Environment Strengthening landscapes with woods and trees

The Tree Charter Principles articulate the relationship between people and trees in the UK in the 21st Century. The final Charter will provide guidance and inspiration for policy, practice, innovation and enjoyment, redefining the everyday benefits that we all gain from woods and trees in our lives, for everyone, from Government to businesses, communities and individuals.

People can find out more and sign the new Charter at: treecharter.uk/sign

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Croaking Science: Courtship & Reproductive Behaviour in Newts and Salamanders

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Courtship and reproductive behaviour in newts and salamanders

Courtship behaviour in newts and salamanders is very different to that of frogs and toads (anurans). In anurans, fertilisation is external so the male expels his sperm whilst the female lays her eggs. However, in newts and salamanders, fertilisation is internal. The male deposits a sperm package, the spermatophore, and the female uptakes this into her reproductive tract to fertilize her eggs. Male newts and salamanders have evolved a range of complex behaviours to encourage the female to uptake the spermatophore. This may involve contact between the male and female, but in aquatic newts of the family Salamandridae, there is no contact and the male encourages the female through complex courtship displays.

male showing belly Matt Wilson spring11
Great Crested Newt ©Matt Wilson

Newts in the genera Triturus (e.g. great crested newt) and Lissotriton (e.g. smooth newt), have similar courtship displays. During an initial orientation phase, the male will move in front of a female and attempt to gain her attention. The female may show no interest and swim away. If successful, the male moves into a static display which involves intense tail fanning and wafting pheromones towards the female. Once the female is fully engaged the male will start to retreat backwards facing the female, still tail fanning. He will then turn around, creeping away from the female with his tail quivering and her following. The male will pause, deposit his spermatophore onto the substrate, walk one body length forward and stop, turning 90 degrees. This allows the female to move so that her cloaca is directly over the spermatophore. She now uptakes the spermatophore for successful fertilisation. Unfortunately, spermatophore uptake by the female will not always be successful so the male has to perform the courtship display from the beginning.

Although males will develop secondary sexual characters during the spring (e.g. tail crest, webbing on the feet), the courtship display takes place in underwater in darkness, so visual cues are likely to be irrelevant. Recent research has shown that the courtship pheromones produced by the male are crucial in ensuring mating success. When a male employs tail fanning, he sends sex-specific pheromones towards the female and these directly impact her responses. In the laboratory, female palmate newts (Lissotriton helveticus) exhibit all the sexual responses up until spermatophore uptake, when in the presence of male pheromones, but no male present. This demonstrates the importance of pheromone production and effective transfer to the female during mating. Previous research has demonstrated that male newts which perform their displays more energetically, have higher mating success. In addition, in male smooth newts (L. vulgaris), males with higher body mass and crest height achieve higher mating success, possibly due to enhanced pheromone production and more effective transfer to the female. This research demonstrates the importance of effective transfer of pheromones by the male towards the female for reproduction.

Smooth newt ©Mike Toms

Male pheromones may have additional effects on females. In the aquatic Spanish ribbed newt (Pleurodeles waltlm), which has both contact and non-contact displays, the male has special glands in the cloaca. When these are released they induce the female’s cloaca to expand and uptake the spermatophore. It has previously been thought that the female doesn’t have a choice over whether she receives the spermatophore from a particular male, once he has clasped her and released his pheromones. However, recent research has demonstrated that females of this species may exhibit thanatosis (feigning death) during courtship prior to the crucial moment of pheromone production by the male. This avoids spermatophore uptake by the female and therefore may provide an escape strategy by a female, should she not want to be persuaded by the male to mate. Thanatosis has previously only been known as an escape strategy by amphibians and has not been observed in a sexual context.

Male newts and salamanders exhibit a range of complex sexual displays. Although many of the behaviours exhibited are widely understood, there are still areas where we have less understanding, such as the effects of pheromones, importance of secondary sexual characters and female choice in mate selection.

 

References

Halliday, T. R. (1974) Sexual behaviour of the smooth newt, Triturus vulgaris (Urodela, Salamandridae). Journal of Herpetology, 8 (4): 277-292.

Green, A. J. (1991) Large male crests – an honest indicator of condition, are preferred by smooth newts, Triturus vulgaris (Salamandridae) at the spermatophore transfer stage. Animal Behaviour, 41 (2): 367-369.

Janssenswillen, S. & Bossuyt, F. (2016) Male courtship pheromones induce cloacal gaping in female newts (Salamandridae). Plos One: DOI:10.1371/journal.pone.0144985.

Teyssedre, C. & Halliday, T. (1986) Cumulative effects of male’s displays in the sexual behaviour of the smooth newt, Triturus vulgaris vulgaris (Urodela, Salamandridae). Ethology, 71: 89-102.

Treer, D., Bocxlaer, I.V., Matthijs, S., Four, D. D., Janssenswillen, S., Willaert, B. & Bossuyt, F. (2013) Love is blind: indiscriminate female mating responses to male courtship pheromones in newts (Salamandridae). Plos One, 8 (2): e56538.

Are amphibian road tunnels putting protected species at risk from pollution?

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Researchers from Froglife and the University of Hull are investigating how endangered and protected amphibians use man-made tunnels to cross roads and also, if such tunnels suffer from chemical pollution from the road traffic above them. A new study, published today in the Water and Environment journal indicates that such road tunnels, while extensively used by amphibians, including the protected great crested newt (Triturus cristatus), can indeed accumulate multiple potentially harmful substances including metals, salt and petroleum hydrocarbons. This is the first published research linking road pollution to amphibian tunnels for the great crested newt.

GCN in amphibian tunnel

Amphibians need water to breed and in a heavily urbanised country such as the UK, the long distances they have to cross between their terrestrial grounds and breeding ponds are often crossed by roads. Roads are not just deadly obstacle courses for amphibians, killing millions each year but also have more insidious effects such as creating barriers for movement, effectively preventing animals from breeding and isolating them in smaller and smaller fragments of habitats. This means that in many parts of the world, amphibian populations have become increasingly fragmented, rare and isolated. Installing amphibian tunnels under roads can be a really positive and important step in order to reduce mortality and encourage connectivity. However, roads are known to be important sources of chemical pollution and amphibians are more susceptible than most animals due to their permeable skin which means dangerous substances can enter the body through direct contact.

Amphibian road tunnel. S. Petrovan

The team of scientists investigated a site with four amphibian tunnels and collected numerous soil and water samples over multiple seasons and compared them to a nearby reference site, away from roads. To their surprise, the amphibian tunnels showed substantial pollution, ranging from high concentrations of metals such as copper and zinc and extreme pH values, much higher than those found in natural habitats. While the presence of chemical pollutants was not unexpected the high levels found came as a shock, especially as the road was very recently built and was less than 3 years old. Metals can accumulate on road surfaces due to car braking and other wear and tear on vehicles, while the high pH may be related to leaching from materials used in road and tunnel construction. Equally, salt concentrations were strongly seasonal, meaning winter applications of road grit were likely responsible. However, other pollutants were more difficult to pinpoint to the source, especially the hydrocarbons. Their impact on amphibians and other species is largely unknown currently, but several pollutants were at concentrations that suggested they could be harmful for the aquatic environment.

Dr Will Mayes from the University of Hull and who led the study said: “This is an interesting initial finding to demonstrate that there is a potential pathway which means amphibians could be exposed to road pollutants in tunnels.  Understanding the risks associated with these pollutants can hopefully inform management guidance to minimise any potentially negative side-effects of amphibian tunnels, which play a key role in mitigating against the impacts of urban developments on amphibian communities.”

Dr Silviu Petrovan, a trustee from wildlife charity Froglife and who participated in the study said: “This is the first study that shows that small amphibian tunnels can accumulate potentially significant pollutants from the road surface. We currently do not know how these interact with amphibians and other species that use the same areas, such as voles, reptiles, hedgehogs and even otters. We need a better understanding of the spread of such road pollutants but also, there are simple measures that can be put in place in amphibian tunnels, especially washing them with a high-pressure water hose at the end of winter, in late February. This is carried out regularly in countries on the continent such as Germany, principally to remove leaf litter that could block amphibian movement but also to remove salt. It is extremely cheap and simple to do.”

 

Citation:

White K, Mayes W, Petrovan S (2017) Identifying pathways of exposure to highway pollutants in great crested newt (Triturus cristatus) road mitigation tunnels. Water and Environment Journal DOI:10.1111/wej.12244

Work Experience Blog

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I am so thankful for getting the opportunity to go to Froglife for work experience. Being at Froglife for two weeks taught me several different skills used in jobs. It helped me improve my concentration, time management as well as communication with others.  I was taught how different jobs work from office jobs to conservation work.

My Name is Saffron and this is what my two weeks of working at Froglife looked like:

Monday 6th March 2017: Monday was the first day I was working at Froglife. I was slightly nervous but then I felt more at ease when I was introduced to everyone that was there and was explained what exactly their jobs consisted of.

Tuesday 7th March 2017: Tuesday involved doing office jobs for a number of employees at Froglife.  I sorted out folders, transferred slides onto a computer, made website updates and some other jobs. 

Wednesday 8th March 2017: I was involved with the Green Pathway project. We went to a Reserve that was about an hour drive away where we met a group of children who were excited to see what was in store. First we played a ball game that boosted team work that helped for the next challenge. The next challenge was to create a picture using only thing that they found in the area around them. Everyone was really eager to climb the hills and walk around the area.  It was a brilliant day out for everyone involved.

Thursday 9th March 2017: This was the first day that I went to Hampton Nature reserve. Once everyone arrived at the meeting point, we headed towards the pond which was being re dug to form a new pond. There was lots of hard work to try and move hibernating newts and other animals so they were not hurt. There were several great crested newts and lizards.  We studied the way they looked and what area the animal was in.

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Friday 10th March 2017: An employee of Froglife took me round different places such as allotments to see what exactly Froglife do other than look after large Nature reserves. One place I was taken to was Boardwalks where I was shown around the most of the Nature Reserve. The person who took me around explained how they resolve the issue of dogs stirring up ponds also how they are dealing with the aftermath of Storm Doris.

Monday 13th March 2017: I spent the day at the office continuing jobs that I did not complete. Some jobs that I did throughout the day was sorting out folders, transferring slides onto a computer and sorting out Toad Patrollers ID.

Tuesday 14th March 2017: Again the day was all office based. There was many jobs that needed doing for different people. Some were difficult some were easy but they all were necessary.

Wednesday 15th March 2017: I was involved with Green Pathway project. We went to Summer Leys.  A bit of a path was closed due to Sand Matins nesting, disappointingly we didn’t see any. With the young people we visited many different bird hides to study the birds in and out of the water also butterflies.  On one of the islands there was a group a sheep used for grazing. As we went around the reserve we were taught about different animals we saw as well as plants and trees. 

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Thursday 16th March 2017: This was the last day that I went to Hampton Nature Reserve. There were more volunteers this week and we went to the other half of the Nature Reserve. Tree branches that were blown down were removed from their spot and moved to the area we were at.  A fire was started and tree branches were chopped and moved into the fire to burn. The fire was a perfect chance to cook some potatoes and marshmallows to eat. The fire blazed hnrthroughout the day and more tree branches were needed. That day built up my confidence because before work experience I would never have done it willingly in fear of failure or being burnt.

Friday 17th March 2017: Today was my final day of working at Froglife. I spent the morning typing up this blog.

I am sad it is over but Grateful for what everyone at Froglife has done for me. I would like to thank everyone at Froglife for everything they have done for me as I have had so many new experiences and learnt new skills. It was one of the best experiences of my life so far.

How did the newt cross the road?

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Researchers from Froglife, The University of Hull and The Open University are discovering how endangered amphibians use man-made tunnels to cross roads. Their work, published in the open access journal PeerJ is the first published research on the effectiveness of these tunnels for our most spectacular amphibian, the protected great crested newt.

Hampton southern GCN tunnel

Amphibians can roam around on land but need to return to water to breed. And, for such small animals, they have remarkable homing instincts, many travelling long distances to the ponds of their birth. They can also travel long distances between ponds in order to find mates, thereby adding fresh blood into new populations. But developments like new roads and houses can get in the way of these migrations. One of the ways that developers try and reduce the impact on amphibians is by building tunnels under roads for them to migrate through. And while this sounds like a great idea, and has been shown to work for some bigger animals, we know very little about whether tunnels really work for amphibians and almost nothing specifically about newts. In Britain, we have a significant proportion of Europe’s great crested newts but they are threatened because habitat loss reduces and fragments their populations. They are also vulnerable to being killed on roads by vehicles and pollutants like road salt.

The team of scientists set out to find out how effective road tunnels are. Using 5 years of monitoring data from a major road mitigation scheme, they provided the first hard evidence that newts use tunnels to move between feeding and breeding sites. This means that road tunnels may help connect populations of newts and other small species across fragmented landscapes, by allowing animals to move between ponds and maintain genetic exchange. Small, isolated populations are otherwise very prone to extinction. But it wasn’t all good news. Writing in the journal PeerJ, they showed that females made much more use of tunnels than males, potentially risking imbalances in the sexes over the long term. And, rather than tunnels connecting newts to ponds as they migrate to breed in spring, most of the action happened in autumn, meaning that tunnels might help newts find their way to their feeding and hibernating sites better than to their breeding ponds. Tunnels are usually accompanied by fences which stop newts wandering onto the road and direct them towards the tunnels. But most of the newts that contact the fences don’t reach tunnel entrances, and of those that do, few attempt to cross. The researchers suggest that maximising the number of tunnels, putting ponds close to tunnel entrances, and on both sides of roads might help resolve these problems.

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Dr Silviu Petrovan, a trustee from Froglife, who led the work said: “This is the first study that has shown that even very long road tunnels, from a newt’s perspective, were used by newts and as such they can be a very important solution for mitigating fragmentation of populations. This is very positive as there is no published data on tunnel use despite the fact that many developments in the UK and elsewhere have employed tunnels as a mitigation measure.”

Cátia Matos, a PhD researcher from The University of Hull who carried out the study, said: “An important finding from our work was that tunnel crossing rates varied substantially between years. Populations are usually monitored for five years after a development has finished, but it is likely that this is not enough time to assess whether mitigation measures have been effective.”

Dr Phil Wheeler from the Open University said: “Even though our work has shown that newts use tunnels, we need much longer monitoring data and from many more sites before we can be confident that tunnels stop fragmented populations dying out. It is essential to know that the resources being committed to wildlife mitigation are being spent in a way which best benefits the target species. Our work is starting to show that, but there is much more to learn.”

 

Citation:

Matos C, Petrovan S, Ward AI, Wheeler P. (2017) Facilitating permeability of landscapes impacted by roads for protected amphibians: patterns of movement for the great crested newt. PeerJ 5:e2922 https://doi.org/10.7717/peerj.2922