This Week in Biodiversity News – 20th July 2022

Policy

The European Parliament has voted to ban ‘fly shooting’ fishing in a part of the Channel. This technique, also known as demersal seigning, involves towing weighted ropes along the seabed at either end of a net, which then encircles and captures entire shoals of fish. Fly shooter vessels catch up to 11 times more fish than inshore fishing vessels and have a devastating effect on the marine ecosystem, biodiversity and local fishers. This decision is seen as a victory for small-scale fishers but it will also help reduce the damage caused to the seabed and marine ecosystems in the Channel. 

A strategy designed to halt biodiversity loss across North Dublin by 2030 will not be achieved in full due to a lack of funding. Fingal County Council has completed the public consultation on its draft Biodiversity Action Plan 2022-2023, but has stated it would cost €4 million annually to implement and therefore two-thirds of the programme will not be achieved by the EU 2030 deadline. The funding gap is stated to be due to other competing priorities, such as housing, roads, sports and community facilities.  

Climate change

Experts are stating that the UK is no longer a cold country and must adapt to extreme heat to prevent thousands of deaths. A specific heat risk strategy must be drawn up by the government, as well as updating housing stock and ensuring that new builds can cool down in hot weather. Scientists are urging governments to work quickly to phase out fossil fuels and reach net zero emissions, as climate change is driving heatwaves, making them hotter, last longer and become more frequent. This comes after warnings that the UK, and countries across the world, could see heatwaves for the rest of summer.

Plastics

UK households recycle only 12% of single-use plastics, disposing of nearly 100 billion pieces of plastic packaging a year. A new survey by Greenpeace is one of the largest voluntary research projects on the scale of plastic waste and it asked households to count their plastic waste for one week in May. Almost 250,000 people from around 100,000 households took part and showed that the largest proportion of plastic waste was from food and drink packaging at 83%. The most common item was fruit and vegetable packaging. On average, each household threw away 66 pieces of plastic packaging in one week.

Pollution

The Environment Agency (EA) is calling for water company bosses to be jailed for serious pollution. Shocking levels of pollution occurred in the last year, with 62 serious incidents of pollution in 2021. The EA has stated that chief executives and board members of companies responsible for the most serious incidents should be jailed and that courts should impose much higher fines. Only three water companies received the highest rating of four stars for their pollution performance. The rating takes into account the number and severity of pollution incidents, as well as self-reporting and the use and disposal methods of sewage sludge. Two companies, Southern Water and South West Water, were given the lowest rating of one star.

Conservation

3D printed reefs are being used to restore marine biodiversity. WWF Denmark and Ørsted have been testing how structures made of 70% sand and 30% pozzolanic cement (a combination of volcanic ash and portland cement) could be used to create new habitats for fish and other wildlife in the Kattegat strait between Denmark and Sweden. Twelve of these structures have been deployed between the wind turbines at Anholt Offshore Wind Farm, and it is hoped that they will help reverse the decline of cod stock in the Kattegat. 

Bison have been released into the wild in the UK. Wild bison are ecosystem engineers and can help to restore biodiversity in woodlands through their natural behaviours, such as felling trees by rubbing against them and grazing. This is hoped to provide a nature-based solution to tackling the climate and biodiversity crisis. The releases are part of a five-year project led by Kent Wildlife Trust and the Wildwood Trust. The next steps include introducing Exmoor ponies, Iron Age pigs and Longhorn cattle. 

Contraceptives are being given to grey squirrels in an attempt to control their population and allow red squirrel populations to improve. Grey squirrels are a non-native species first introduced from North America in the 19th century. They cause significant damage to UK woodlands as they strip the bark from trees, and they tend to target younger trees that are typically between 10-50 years old, either killing them or maiming them and leaving them vulnerable to pests and diseases. Culling has not been found to be a sufficient control measure, therefore it is thought that using contraceptives, which have longer-lasting effects, may be more effective.

Young Maori divers are hunting invasive crown-of-thorns starfish to save coral reefs. The species, also known as taramea, feed on coral reefs and, when there are too many individuals, can destroy reef habitats. Korero O Te `Orau, a local environmental organisation, has been training young Maori people in scuba diving to remove taramea from the reef and bury them inland. The recent outbreak of this species around the island of Rarotonga in the Cook Islands could jeopardize the survival of the surrounding coral reef if not tackled properly. More than 3,700 taramea have been collected so far.  

Research 

Great white sharks might change their colour when hunting prey. Researchers conducted experiments off of South Africa using a specially designed colour board with white, grey and black panels. Each shark was photographed as it jumped out of the water at the panels, with the experiment being repeated throughout the day. One particular shark appeared to be both dark grey and a much lighter grey at different times. The results were verified using computer software to correct for variables such as weather, light levels and camera settings. While the research has not yet been validated and published in a scientific journal, experts are still excited about the results.

Equipment in Focus: NHBS Harp Trap

We are pleased to announce that we are now able to resume manufacturing the NHBS Harp Trap! We have had the time to be able to think about the design of the trap and tweak it to make it easier to use. At first glance, this compactly packed harp trap may look as though it would be tricky to set up, but rest assured that, with the use of two people, you’ll be able to easily assemble this trap, even in the dark. This blog provides a step-by-step guide to how to set up and disassemble the trap. If you are interested in finding out more general information about the NHBS Harp Trap, the only harp trap that is commercially produced in Europe, and its use, please check out the blog we wrote when we first launched the trap.

Please note that the NHBS Harp Trap is a made-to-order item so please contact us if you would like to purchase one and we will be happy to advise the current lead time. 

The NHBS Harp Trap: Instructions

Please follow these instructions for correct assembly and disassembly. We recommend that this is carried out by two people.

Assembly

1. Carefully remove the harp trap from its carry bag and sit it upright on the floor still wrapped up. Remove the legs and upright support poles from on top of the trap.

2. Insert the legs at either end of the frame (it is easiest to do this one end at a time). Hand tighten the top thumb screws (A). The lower thumb screws (b) are for extending the legs to make the trap higher or balanced if on uneven ground; the leg lengths can be adjusted as needed after the trap is assembled.

3. Undo the material ties at the bottom of the trap (C) to unroll the green catch bag flap so that it is laid out on the floor (D).

4. Fully open out the catch bag assembly arms to their full width (D).

5. Remove the upper carriage securing pin by loosening the upright support pole thumb screws (E). Where the upper carriage securing pins have been removed, insert upright support poles and allow them to rest on the ground. Ensure that the fixing points (thumb screws) on the upright support poles are facing each other.

6. Release the spring locking pins from both ends of the trap by pulling the leaver out and rotate it 90° to lock in open position (F).

7. Remove the thumb screw from the top of each upright support pole and slowly raise the top line carriage, keeping both ends level and watching closely to ensure that the lines do not become jammed. Once the carriage reaches the fixing point secure with upright support pole thumb screws.

8. Once you are confident that the top carriage is secure, slowly lift the upright support poles in unison again, and carefully watch the lines to ensure that none get caught. Keep raising until the lines become taut. Engage both spring locking pins in the bottom carrier (reverse of F), check the tension is even at both ends of the trap and when happy tighten the two thumb screws at the base of the upright support poles evenly at both ends to secure.

9. If required, peg out the guy ropes for extra stability.

Disassembly

1. If guy ropes have been used pull out the red pegs and store them carefully. Now wind up the guy ropes.

2. While holding on to the upright support poles (one person at each end), loosen the thumb screws at the base of the upright support poles, holding them in position and allow them to lower slightly. Disengage the spring locking pins on each end (as in F) and start to wind the lower line carrier. Keep lowering the upright support poles slowly and evenly while winding the line carrier until the upright support poles reach the floor.

Care must be taken to not allow the line to come free off the end of the line carrier as this may result in snagging of the lines and subsequent breakage – guiding the lines with your hand/arm while lowering is essential (H).

3. With the upright support poles resting on the ground, remove the top carriage securing thumb screws and allow the line carrier to lower, guiding the line with your hand/arm and winding as you go (H). Return the top line carrier thumb screws back to the storage points in the upright support poles.

4. Once the top carriage has been fully lowered, engage the spring locking pins, remove the upright support poles, and secure the top carriage back into storage position using the upper carriage securing pin and tighten the thumb screws to secure in place (reverse of E).

5. Fold the arms of the catch bag assembly inwards as far as they will go, wrap the bag around the trap and tie the bottom attached material straps to secure in place.

6. Undo the top thumb screws that are securing the legs and remove each leg. For safekeeping, ensure that the thumb screws are tightened once the legs have been removed.

7. Fully collapse each leg to its minimum length and tighten with thumb screws.

8. Place the upright support poles and legs back on top of the closed trap and secure them in place using the attached material ties at either end. Carefully place the trap and accessories bag back in the carry bag safely ready for next time.

Spares and accessories included:

4x Guy rope 5m
4x Red pegs
1x Roll of nylon string
1x Accessories bag

The NHBS Harp Trap is available on the NHBS website. The trap is available as a three-bank trap as standard, but please contact our Workshop Team to discuss your requirements if you would like a bespoke two or four-bank trap, or if you would like a trap that has the ability to be suspended from a support.

To view the full range of NHBS manufactured items, along with other ranges of survey equipment, visit www.nhbs.com. If you have any questions on the NHBS Harp Trap or would like some advice on the best survey equipment for you then please contact us via email at customer.services@nhbs.com or phone on 01803 865913.

 

A guide to conservation land management and greenhouse gas emissions

Managing habitats for the benefit of wildlife can often contradict climate priorities. In the Summer 2022 issue of Conservation Land Management (CLM), Malcolm Ausden and Rob Field describe how different habitats and their maintenance impact the climate, and highlight the management practices that provide the greatest climate benefits. Here you can read a summary of the article.

Quantifying the impacts of habitat management on the climate

The influence of different habitats and their management on the climate can be measured by estimating the net flux of the most important greenhouse gases (GHGs): carbon dioxide, methane and nitrous oxide. The contribution of the latter two is usually expressed in terms of the amount of CO2 needed to produce the same level of warming (tonnes of CO2 equivalent; t CO2e), as determined by global warming potential (GWP) of the different gases. A positive GWP indicates a positive warming effect, whereas a negative GWP shows a cooling effect. GWP values are usually expressed in comparison to the warming potential of CO2 over 100 years.

The effects of conservation land management on GHG flux

In the full CLM article, the authors describe the GHG flux of the main types of habitats in Britain, and how this is affected by conservation management. The habitats included are listed below, starting with those that produce the greatest overall warming effect on the climate, and finishing with those that have a cooling effect.

  • Intensive arable on organic soil 
  • Intensive grassland on organic soil
  • Eutrophic/mesotrophic open water
  • Lowland wet grassland on organic soil
  • Intensive arable on mineral soil (incl. emissions from farming operations)
  • Bare peat
  • Oligotrophic open water
  • Heather-dominated drained bog
  • Intensive arable on mineral soil (excl. emissions from farming operations)
  • Lowland and upland heathland
  • Unimproved low-input grassland (incl. LWG on mineral soil)
  • Near-natural bog
  • Improved grassland (excl. emissions from farming/livestock operations)
  • Near-natural fen
  • Mudflat
  • Conifer plantation on mineral soil (managed on a 55-year-rotation)
  • Saltmarsh
  • Dry broadleaved woodland (mean over first 100 years)
  • Wet woodland
  • Dry broadleaved woodland (mean over first 30 years)
Conifer plantations can have a cooling effect on the climate if grown on mineral soil and managed on a 55-year-rotation. Image by Andrew Arch via Flickr.

Intensive arable on organic soil (soils derived from peat) produces the biggest warming effect per unit area, as large quantities of CO2 are released via oxidation of dried-out peat that is repeatedly exposed during the cultivation process. The manufacture and use of nitrate fertilisers and the use of machinery also contributes to significant emissions of GHGs. At the other end of the spectrum is dry broadleaved woodland, particularly during the first 30 years after its establishment. The GHG flux of woodland fluctuates depending on its age, species composition, the density and growth rate of trees, and management. For unmanaged woodland, the net uptake of CO2 is low while trees are small, and planting of trees can even lead to a net release of CO2 as a result of soil disturbance. The rate of CO2 uptake increases during the main growth stage of the trees, slowing as they mature, although carbon does continue to accumulate in the soil.

Ways to benefit both the climate and wildlife

Conservation management can provide climate benefits either by reducing the amount of GHGs released into the atmosphere, or by actively removing them (i.e. carbon sequestration). For example, rewetting drained peatland reduces, and should eventually stop, the release of CO2 that occurs through the drying out and oxidation of peat. Although there is an initial release of methane after rewetting, accumulation of carbon in the peat will resume. The climate benefits per unit area of wet peatland are surprisingly low compared to some other types of habitat, but due to the large quantities of carbon stored within the vast expanse of peat in upland Britain, rewetting drained areas is an incredibly important measure to prevent the ongoing release of CO2, and will also provide a number of benefits for wildlife.   

On organic soils used for arable, the greatest climate benefits per unit area come by creating wet woodland, as this prevents the oxidation of the peat and allows carbon to accumulate during tree growth. There are, however, limited opportunities to create new wet woodland on ex-arable organic soils and to keep them adequately saturated. The next best option is the creation of swamp/fen, which offers far greater climate benefits than agriculturally drained peat soils, even though the habitat itself has an overall GWP100 near to zero.

Swamp/fens offer far greater climate benefits than agriculturally drained peat soils. Image by Liz West via Flickr

The authors look at multiple management approaches and describe the climate benefits of different types of habitat restoration and creation. All the methods listed below are beneficial for the climate, and are ordered here by the magnitude of their cooling effect, from the least to the greatest. 

  • Creating swamp/fen on ex-arable on mineral soil
  • Rewetting drained bog 
  • Creating lowland wet grassland on ex-arable on mineral soil
  • Creating intertidal habitat on ex-arable on mineral soil
  • Establishing broadleaved woodland on ex-arable on mineral soil
  • Creating lowland wet grassland on drained grassland on organic soil
  • Creating swamp/fen on drained grassland on organic soil
  • Creating lowland wet grassland on ex-arable on organic soil 
  • Creating swamp/fen on ex-arable on organic soil
  • Creating wet woodland on ex-arable on organic soil

A large aspect of the management of semi-natural habitats involves cutting and clearing vegetation in order to maintain a particular vegetation structure and to slow or reverse succession. But this means that the amount of carbon accumulated in the soil and vegetation is reduced. In addition, the removal of vegetation is often carried out by using domestic livestock, which release large quantities of methane, by machinery, which is often powered by fossil fuel or biofuel and releases CO2, or by burning, which also releases CO2. 

Domestic livestock release large quantities of methane. Image by USDA NRCS Montana via Flickr

But there are changes that can be made to management that can help contribute to a habitat’s cooling effect. For example, the amount of vegetation that is removed from a site can be reduced to allow more carbon to be stored in the vegetation or soil. In some instances this can mean allowing a site, such as a swamp/fen, to develop into woodland or scrub. This can contradict conservation goals where maintaining an early successional habitat is the priority, but can be an option for sites that are currently poor for wildlife. 

Another option is to change the method used to clear the vegetation. One way that this can be achieved is by swapping livestock for grazers that release less methane per quantity of vegetation removed. Ponies, for example, produce much lower levels of methane compared to cattle and sheep, although before changing the type of livestock it is important to understand that different livestock have different effects on vegetation structure and composition. In the full article, the authors explore this and other changes that site owners can make to increase the cooling effect of different habitats and their management.

It can be difficult for conservationists and land managers to know how to best manage a site in the interest of both nature conservation and the climate, and in many cases there are trade-offs between maximising the benefits for the two. But as the article demonstrates, there are restoration approaches that can be used that provide significant climate and conservation benefits, and it is helpful to consider and quantify the net flux of GHGs before implementing any changes to conservation management plans.

Other articles featured in the Summer 2022 issue include:

  • Saltmarsh restoration through flash re-creation
  • Measuring conservation success on farmland
  • Viewpoint: Dams without beavers: could beaver dam analogues yield benefits in the UK?

In this and every issue you can expect to see Briefing, keeping you up to date with the latest training courses, events and publications, and On the ground which provides helpful tips or updates on products relevant to land management. Other features that regularly appear in CLM include Viewpoint, a similar length to our main articles, but here authors can voice their own views on various conservation issues, and Review, which can include letters from readers or updates from our authors.

CLM is published four times a year in March, June, September and December, and is available by subscription only, delivered straight to your door. Subscriptions start from £22 per year. Previous back issues are also available to purchase individually (subject to availability).

If you are involved in a conservation project and think your experiences could be useful to other practitioners, we would love to hear from you. If you are interested in writing for CLM feel free to contact us – we will be happy to discuss your ideas with you.

Phenology Series: Summer

For those of us living where there are four distinct seasons, summer is the period of long, warmer days where the skies, fields, lakes and mountains are alive with the busy activities of plants and animals at the peak of their growing year. Most of the animals that have hatched or been born earlier this year will be beginning to fend for themselves, while many plant species will be coming to the end of their flowering period and preparing to produce seed in an effort to ensure their survival and proliferation.

The combination of warmer weather and longer daylight hours makes this the perfect time to get out and about and experience the beauty and complexity of the natural world.

This is the second in our seasonal phenology series where you can explore a carefully chosen collection of ID blogs, books, equipment and events, all designed to help you make the most of a summer outside. Check out our spring blog and don’t forget to look out for our autumn blog in September.

Identification guides:

 

 

 

 

 

 

 

 

What you might see:

• Hedgerows and verges are still home to lots of flowering plants, although the frothy drifts of cow parsley are now coming to an end. Honeysuckle can be seen blooming from June, providing a night-time food source for moths such as the Elephant Hawkmoth (Deilephila elpenor).

• Bee orchids (Ophrys apifera) will flower briefly in June and July on dry, chalk and limestone grasslands, while sea cliffs will be adorned with the delicate blush of sea thrift (Armeria maritima) from April to October.
• Auks, such as Razorbills (Alca torda), Guillemot (Uria aalge), Puffins (Fratercula arctica) and Fulmar (Fulmarus glacialis), come to their cliff nests in spring to lay their eggs. They can still be seen (and heard!) throughout the summer as they make frequent trips out to sea to catch food for their young. Further inland, summer visitors such as Redstart (Phoenicurus phoenicurus), Wood Warblers (Phylloscopus sibilatrix) and Pied Flycatchers (Ficedula hypoleuca) are wonderful to catch a glimpse of.

• June to August is an important time for ladybirds. During this period, mated females will lay their eggs which then hatch into larvae and form pupae through a series of four stages, or ‘instars’. Adult ladybirds emerge from the pupae in August.
• Wasps, bumblebees, honeybees and butterflies are all active in the summer and will feed as much as possible while the weather is fine. Small Tortoiseshell (Aglais urticae) and Red Admiral (Vanessa atalanta) butterflies can both be frequently seen around nettles where they like to lay their eggs.
• Frogs and toads spend their days keeping cool in damp and shady areas and are often found in overgrown areas of the garden during the summer. This year’s froglets and toadlets will remain in the water until late summer.

• The summer months are a great time to spot bats hunting for insects during the dusk and dawn hours. Female bats give birth to their young in June and within three weeks these juveniles will be learning to fly themselves. By August the youngsters will no longer need their mother’s milk and will be hunting for their own food.

Activities:

Upcoming events

Big Butterfly Count – 15th July to 7th August
British Dragonfly Week – 16th to 24th July
National Marine Week – 23rd July to 7th August
International Bat Night – 27th to 28th August

Essential equipment and books:

Field Guide to the Moths of Great Britain and Ireland

This beautifully illustrated and comprehensive field guide shows moths in their natural resting postures. It also includes paintings of different forms, underwings and other details to help with identification.

 

 

Britain’s Reptiles and Amphibians: A Guide to the Reptiles and Amphibians of Great Britain, Ireland and the Channel Islands

This detailed guide to the reptiles and amphibians of Britain, Ireland and the Channel Isles is designed to help anyone identify a lizard, snake, turtle, tortoise, terrapin, frog, toad or newt with confidence.

 

The Wild Flower Key: How to Identify Wild Flowers, Trees and Shrubs in Britain and Ireland

This essential wild flower guide is packed with identification tips and high-quality illustrations, as well as innovative features designed to assist beginners. The text aims to be as useful as possible for those working in conservation and includes a compilation of the latest research on ancient woodland indicator plants.

 

NHBS Moth Trap

A lightweight and highly portable trap, tested and approved by Butterfly Conservation. This mains-powered trap runs a single 20W blacklight bulb (included) and comes supplied with a 4.5m power lead with UK plug.

 

Kite Ursus Binoculars

These affordable binoculars have been designed for everyday use and have a robust housing, great field of view and produce a bright, colour-balanced image.

 

Magenta Bat 5 Bat Detector

A handheld super-heterodyne bat detector with an illuminated easy-to-read LCD frequency display. This fantastic entry-level detector converts ultrasonic bat calls into a sound that is audible to humans, allowing you to listen to and identify the bats flying around you.

 

 

Browse our full collection for more field guides and equipment highlights.

This Week in Biodiversity News – 6th July 2022

Climate change

The US Supreme Court has limited the Environmental Protection Agency’s (EPA) ability to curb power plant emissions, impacting America’s attempts to fight climate change. The Supreme Court ruled that the Clean Air Act does not give the EPA broad authority to regulate greenhouse gas emissions from power plants. The Biden administration plans to combat climate change by cutting the nation’s greenhouse gas emissions in half by the end of the decade and aiming for an emissions-free power sector by 2035. Now, the decision to curb power plant emissions must be taken by Congress itself, or “an agency acting pursuant to a clear delegation from that representative body.”

In other climate news, both Spain and Portugal are suffering the driest climate for at least 1,200 years, according to new research. Azores highs, high-pressure systems off the coast that blocks wet weather fronts in winter, have dramatically increased since 1980, pushing wet weather northwards. This is having severe implications for both food production and tourism. This change has been conclusively linked to increased anthropogenic emissions.

Scientists have warned Members of the European Parliament (MEPs) against watering down EU deforestation laws. Last week, a draft regulation was rewritten to define ‘forest degradation’ as the replacement of primary forests by plantations or other wooded land. As primary forests account for only 3.1m hectares of 159m hectares of overall forest, this definition would severely limit the law’s reach to only 2% of the total forest area.  A letter from more than 50 scientists has stated that any exclusion of forest degradation from the law would undermine the EU’s desire for Europe to “become the first climate-neutral continent by 2050.”

Conservation

Bird flu has been confirmed at the UK’s only breeding colony of roseate terns in Northumberland. This “new virulent” form of bird flu is having a devastating impact on a number of wild bird species, with hundreds of seabirds found dead on Coquet Island. There are now calls for the government to develop and implement a national response plan for bird flu in wild birds, including clarity for collecting dead birds and a long-term plan for future threats. This disease is affecting all four species of tern on the island, as well as eider ducks, black-headed gulls and large gulls. The island is also home to nesting puffins but, so far, no puffin deaths have been recorded.

A £4.1m scheme has been revealed to improve wildlife habitats and alleviate flooding alongside roads in Stafford. The Stafford Brooks Project will target 25 locations near local rivers and streams to address the environmental impact of roads. Space will be created for wildflowers, trees and wildlife in areas where habitats have been impacted by activities from previous road building. New wetlands and reed beds are also being designed to help filter polluted run-off from roads, which can significantly impact river health.

A 3-metre-high weir in Cumbria is being demolished as part of a national push to allow fish and invertebrates to move more freely along the UK’s rivers. The River Kent is an internationally important site of special scientific interest as its home to species such as white-clawed crayfish and freshwater pearl mussels. The removal of Bowston weir will help to renaturalise part of the River Kent by improving biodiversity, restoring migration routes and reducing flooding risks for local residents.

The greater glider is now considered endangered due to population declines caused by logging, bushfires and global heating. This cat-sized marsupial has slipped from vulnerable to endangered on the federal government of Australia’s list of threatened species. There are calls from experts and conservationists to back this move with urgent action to preserve habitats and reduce greenhouse gas emissions.

Research

Researchers are satellite-tracking whale sharks to explore the factors influencing their behaviour in the coastal waters of the Panamanian Pacific, including migratory and feeding behaviours. Rhincodon typus is vulnerable to population declines due to their slow maturation and they face a number of threats from humans, including entanglement in fishing nets and boat strikes. This study has shown that whale sharks spend more than 77% of their time in areas without any protection, indicating that conservation measures should go beyond the creation of local marine protected areas. 

A new study, part-funded by The Mammal Society, has revealed the presence of plastic consumption in small mammals. More than 261 faecal samples were analysed to assess the exposure of seven terrestrial UK mammals to plastics. Four species, the European hedgehog, wood mouse, field vole and brown rat all had plastic polymers detected within their faecal samples. This ingestion was shown to occur across species of differing dietary habits and locations, confirming that plastic consumption is a widespread issue.

New Discoveries

A new giant water lily species has just been discovered, despite being in the archives of the Royal Botanic Gardens, Kew, for 177 years. Now holding the record as the world’s largest water lily, with its leaves growing more than 3m wide, the Victoria boliviana grows in a single water basin in part of the Amazon river system in Bolivia. It was long suspected to be different from the two other known giant species, V. amazonica and V. cruziana, but it was only when Kew grew all three side-by-side under exactly the same conditions that they could clearly see V. boliviana was totally different.

Policy

Singapore strengthened a law on Monday 4th July to stamp out wildlife trafficking, with stiffer penalties for those found guilty. The changes to the Endangered Species (Import and Export) Act include tripling the maximum jail term for individuals from two to six years and increasing the maximum fine from $50,000 (~£29,550) per species to $100,000 (~£59,100) per specimen. Companies involved in the trafficking of endangered species will also face higher fines and prison sentences, according to the Senior Minister of State for National Development, Tan Kiat How.

Climate Challenges: 6. Agricultural Intensification

In the lead up to the 26th UN Climate Change Conference of the Parties (COP26) in November of last year, as well as the months that have followed, we have been writing a series of articles looking at some of the toughest global climate crisis challenges that we are currently facing. This post looks at the intensification of agricultural practices and how this can both be exacerbated by and contribute to climate change.

Farmer applying pre-emergence sprays. Chafer Machinery via Flickr
What is agricultural intensification?

Our global population is increasing year on year and is predicted to hit 10 billion by 2057. Agricultural production has to keep pace with the resource demands of this growing population. There are two main ways this can occur: an increase in the amount of land used for agricultural purposes or an increase in the yield from land already used through improvements or increased use of resources such as technology, fertilisers, labour, pesticides or scientific plant knowledge.

What are the impacts of land-use change?

Habitat destruction is considered one of the main causes of animal extinctions worldwide, and much of this destruction is due to clearing land for agriculture. Intensively managed agricultural land is far less valuable for the environment than natural habitats such as wetlands and forests. Intensively managed farmlands support less diverse and abundant species, sequester less carbon dioxide and suffer from increased water loss and soil erosion. Therefore, the increase in agricultural areas can contribute to climate change and worsen our ability to mitigate its effects.

Agricultural expansion and land clearing are pushed right up to Bwindi Impenetrable National Park boundaries in Uganda. USAID Biodiversity and Forestry via Flickr
What is the impact of increasing yields?

Intensification of agricultural management practices to increase yield includes an increase in the use of chemicals such as fertilisers, herbicides and pesticides, all of which can negatively impact wildlife, soil and nearby water quality. The artificial introduction of nutrients can be detrimental to the environment, particularly if it reaches waterways through run-off, as it can lead to algae blooms that can deplete aquatic oxygen levels.

Herbicides and pesticides have a direct impact on both target and non-target species, potentially disrupting populations and affecting whole ecosystems. Species can also be impacted through trophic poisoning, as the impacts of these chemicals can be heightened through biomagnification, where toxins build up in the food chain in greater and greater concentrations at each trophic level. This often results in the loss of top consumers which can destabilise ecosystems.

Another way to increase yield is by utilising as much of the existing agricultural land as possible. This, however, reduces the areas of non-crop species, such as trees and hedgerows. These areas represent essential diversity in plant species, helping to support a wide variety of fauna by providing food, shelter and breeding areas. Losing these areas reduces the variety and abundance of species that agricultural land can support. Additionally, crops are often grown in monocultures, a field composed of just a single crop species rather than multiple species, further reducing biodiversity. This increases the susceptibility of fields to disease and pest damage, furthering the need for additional chemical intervention.

Monoculture by Paul Barker Hemings via Flickr
Climate change and agricultural intensification

Agriculture is one of the major sources of greenhouse gases that contribute to climate change. Methane and nitrous oxide, produced from livestock and as an indirect product of fertilisers, are particularly problematic. Increasing production or land area can increase the amount of greenhouse gases released into the atmosphere while reducing the amount of carbon that the land can sequester, enhancing the impact on climate change.

Climate change affects agriculture in return. Changes in precipitation patterns impact crop yields and reduce yield reliability. Higher temperatures, particularly heat waves, can lead to high yield losses, livestock death or sickness, a reduction in workable hours, increases in water supply needs and even damage to equipment. More frequent and higher intensity extreme weather, such as storms, can also impact in a similar way. Therefore, agriculture may not be able to keep up with food demands and would need to further increase its production. This could continue to drive climate change and exacerbate the impacts on agriculture in a cycle of detrimental effects.

What are the other options?

One solution is reducing food loss (by food suppliers) and waste (by retailers, food service providers and consumers). It is thought that, globally, around one-third of all food produced for human consumption is lost or wasted every year. This amounts to about 1.3 billion tonnes of food per year. When this is buried in landfills, it is broken down by microorganisms using anaerobic digestion, producing greenhouse gases (specifically methane and carbon dioxide), which are released into the atmosphere. Some countries, however, have begun to set up food recycling centres to capture these gases to be used as a renewable source of biofuel.

Food waste recycling plant in America. James Loesch via Flickr

By reducing the amount of food wasted, there would be less need to increase agricultural intensification to keep up with the growing population. This can be achieved through several routes, including changing the strict cosmetic standards of many retailers, providing better clarity on food expiration dates and bringing consumers’ attention to how much food they waste each year. For example, through a campaign called ‘Love Food, Hate Waste’, the UK had a 21% reduction in avoidable household waste between 2007 and 2012.

Sustainable farming practices are needed to ensure that global agriculture does not continue to seriously contribute to climate change. Through research into sustainable practices and better techniques, agriculture may be better able to provide enough food for the global population without compromising our environment. By reducing livestock numbers, increasing the efficiency of fertiliser application and better management for manure, the EU reduced agricultural emissions by 24% between 1990 and 2012. Additionally, the UK government is changing how they subsidise farmers. The Sustainable Farming Incentive, piloted by Defra, will reward acts that improve environmental outcomes and reduce carbon emissions. This should hopefully help to increase the sustainability of our agriculture, reducing its impact on climate change.

Another potential solution is regenerative farming, a practice that aims to reverse the impacts of and contribution to climate change by rebuilding soil organic matter and restoring degraded soil biodiversity. This results in an increase in carbon drawdown and an improvement in the water cycle. These farming practices include low- or no-till techniques, increasing plant diversity, introducing cover crops and crop rotations and minimizing physical disturbance. It also includes growing trees and shrubs around crops, using perennial crops that do not need to be replanted annually and creating borders of pollinator habitats. It is hoped that, by restoring the health of soils, farms will be able to increase their yield without negatively impacting the environment, reducing the need for agricultural intensification.

Tilling is used to aerate the soil, prepare seedbeds, suppress weeds, level soil, incorporate fertilisers and turn over cover crops. however, tilling contributes to soil erosion, surface runoff and carbon emissions. Image by United Soybean Board via Flickr

There is a concern, however, that the reduced tilling may lead farmers to rely more heavily on herbicides to remove unwanted plants. There may also be an increased use of fertilisers, to meet the need for nitrogen to convert carbon into microbial organic matter to allow it to remain sequestered in the soil. Questions have also been raised about whether regenerative farming can sequester additional soil carbon effectively, without decreasing yield or requiring more land for farming. For example if cover crops or additional trees and shrubs are added to farmlands without decreasing yield, then carbon sequestration will increase. However, if yield decreases and habitats such as a forest have to be cleared to replace lost production, then carbon sequestration will either remain the same or decrease.

COP26

There were several pledges and agendas launched at COP26 last year, including the Glasgow Leaders’ Declaration on Forests and Land Use, which intends to halt and reverse forest loss by 2030, reducing agricultural expansion into forest areas; and the Agriculture Innovation Mission for Climate (AIM4C), which looks to fund scientific breakthroughs, public and private applied research, and the development, demonstration and deployment of tactical, actionable and innovative products services and knowledge to producers. AIM4C has been criticised, however, for being over-reliant on technological solutions rather than sustainable farming methods. Other announcements including the climate emissions pledges and the Global Methane Pledge will also impact agriculture and its contribution to climate change, as countries look to introduce new regulations and policies to reduce emissions from farms.

The Koronivia Joint Work on Agriculture (KJWA) was also discussed at COP26. Originally established at COP23 in 2017, KJWA aims to bring discussions of agriculture into the UNFCCC and address agricultural issues through the lens of climate change. This process was set to end at cop26, but due to many areas of disagreement, the roadmap of how the Koronivia process will be going forward was included in the debate at the next meeting of the UN climate process, the Bonn Climate Change Conference, in June 2022.

Summary
  • Agriculture must keep up with the resource demands of an increasing global population. This is mainly achieved through increasing agricultural land or increasing yield. Both have negative environmental impacts and can contribute to climate change.
  • Climate change can also negatively impact agriculture, through changing precipitation patterns and extreme weather causing loss of crops and damage to equipment. This, then, requires more agricultural intensification to make up for losses, further contributing to climate change.
  • Solutions include more sustainable agricultural practices and reducing food waste. This reduces the impacts of agriculture on climate change while also reducing the need for more agricultural intensification. Other practices such as regenerative farming may help to improve soil health and carbon sequestration but there are criticisms about its effectiveness.
  • Several pledges launched at COP26 will impact agriculture and its contribution to climate change, including the Glasgow Leaders’ Declaration on Forests and Land Use, the Global Methane Pledge and the Agriculture Innovation Mission for Climate.
Useful resources:

The Food and Agriculture Organization of the United Nations’ (FAO) 2013 report: food wastage footprint: impacts on natural resources, illustrating how food is wasted or lost through various stages of the supply chain, highlighting the significant environmental costs.

The 2021 policy paper for the Sustainable Farming Incentive, piloted by the Department for Environment, Food & Rural Affairs (Defra).

This 2015 article by the European Environment Agency on agriculture and climate change.

A 2019 document outlining the National Farming Union of England and Wales’ (NFU) plans for achieving net zero, outlining the current impacts of agriculture and their goals for increasing sustainability.

This 2018 report by IEA bioenergy on anaerobic digestion of food waste for a circular economy, containing food waste data, information on anaerobic digestion systems, and case studies from 11 different countries.

This 2021 article on the key outcomes from COP26 for food, forests, land use and nature by CarbonBrief.

 

Sixty Harvests Left: How to Reach a Nature-Friendly Future

Taking its title from a chilling warning made by the United Nations that the world’s soils could be gone within a lifetime, Sixty Harvests Left demonstrates why food and future harvests matter more than ever and shows us how we can restore our planet for a nature-friendly future.

 

 

Farming and Birds

Ian Newton discusses the changes that have occurred in British agriculture over the past seventy years, and the effects they have had on bird populations. He explains how different farming procedures have affected birds and other wildlife, and how an understanding of the processes involved could help in future conservation.

 

 

Soil Health and Intensification of Agroecosystems

This book examines the climate, environmental, and human effects on agroecosystems and how the existing paradigms must be revised in order to establish sustainable production.

 

 

 

Agricultural Development and Sustainable Intensification

This multidisciplinary book presents state-of-the-art reviews of current SI approaches to promote major food crops, challenges and advances made in technology, and the institutional and policy measures necessary to overcome the constraints faced by smallholder farmers.

 

 

Sustainable Intensification of Agriculture: Greening the World’s Food Economy

This book provides the first widely accessible overview of the concept of sustainable intensification as an innovative approach to agriculture and as a key element in the transition to a green economy.

 

 

Farming with the Environment: Thirty Years of Allerton Project Research

This book examines over 30 years’ worth of research from the Allerton Project, a research and demonstration farm in the UK. Designed to provide guidance, feedback and recommendations to farmers, practitioners and policymakers, the Allerton Project is an exceptionally well-documented case study of lowland agricultural land management which has the purpose of meeting multiple objectives.

Help! I Need an Ecologist: Advice for Homeowners

Most development projects will require an environmental survey. Image by John K Thorne via Flickr.
When and why you might need an ecologist

You’re likely to need to employ an ecologist if you are planning to build a house or add to or alter an existing building. An ecologist will conduct the surveys necessary to assess the possibility of the project impacting any ecosystem or habitat which is home to a protected species.

You will need a survey if the site includes or is adjacent or connected to any of the following, although your architect, planning agent or local planning authority should be able to advise you on this:

  • Woodland, hedgerows or scrub
  • Lakes, ponds, ditches or other bodies of water
  • Meadow, pasture or parkland
  • Heathland
  • Coastal habitat
  • Large rural or suburban gardens
  • Complex tree structures, caves or cave-like spaces
  • Existing derelict buildings, farm buildings or timber buildings, particularly those with access into roof spaces.

The first step in the process is usually a Preliminary Ecological Appraisal. This survey will identify evidence of any protected species or habitat suitable for supporting a protected species. If any are found then this will inform what further protected species surveys or vegetation surveys are required.

It is important to talk to an ecologist as early as possible in the planning process. Image by Rebecca Siegel via Flickr.
What is a Preliminary Ecological Appraisal?

A Preliminary Ecological Appraisal is conducted by an ecologist and usually involves both a desk-based study and a walkover/habitat survey. The desk-based study looks at local records to see if there is current evidence of protected species being present up to 2km away from your site. It will also look to see if the project has the potential to impact any nationally or internationally protected areas. The walkover survey (sometimes referred to as a Phase 1 or Extended Phase 1 survey) will assess what types of habitat are on and around the area as well as the likely presence of any species that are currently protected. It will also look at the value and significance of the habitat.

Once these are complete, the ecologist will compile a report for you that will include this information, as well as an assessment of how the project might impact the surrounding habitat/protected species and any legal issues that might be raised by the development. If no evidence of protected species is found, no further surveys will be required. However, if they find that the site of your project is home to one or more protected species, or that the habitat is likely to support them, then further species-specific surveys will be required.

The report may also make recommendations as to how the local biodiversity can be improved upon during and following the development in line with Biodiversity Net Gain guidelines. This national policy aims to improve biodiversity by creating or enhancing habitats in association with development, so that the environment is left in a better state than it was before the project began.

Further species-specific surveys may include surveying for bats using passive recorders.
What further surveys might be required?

If your Preliminary Ecological Appraisal suggests that there are protected species or their supporting habitat present on or around the development site, then more detailed protected species surveys will be required. Commonly referred to as Phase 2 surveys, these may include botanical surveys, as well as those for bats, great crested newts, hazel dormice, reptiles, water voles, badgers and breeding birds. All of these types of surveys will involve the ecologist(s) conducting at least one, but more likely a series of, site visits. There may be seasonal constraints as to when they can do this.

Once all surveys are complete, the ecologist will compile a report (usually referred to as an Ecological Impact Assessment report or EcIA) which presents their findings as well as the likely impact of the project on protected habitats and species. It will take into account your building and landscape plans including details such as proposed drainage and lighting. The report will also recommend the measures that can be taken to avoid, mitigate or compensate for the impacts, as well as how the local biodiversity could be enhanced.

For sites that might impact a European protected site, such as Special Areas of Conservation (SAC), Special Protection Areas (SPA) and Ramsar sites, an additional survey known as a Habitats Regulation Assessment might be required. This must be submitted by a competent public body (usually the local planning authority), although the work will most likely be carried out by a consultant ecologist. This will assess whether the project is likely to impact the site due to factors such as increased recreational pressure on the area, or significantly increased noise, light and water pollution.

Great crested newt surveys must be conducted during the spring. Image by Chris H via Flickr.
How to find an ecologist

There are numerous ecological consultancies located throughout the UK and Ireland, ranging from small or sole traders up to companies that employ large numbers of ecologists with multiple offices around the country. An internet search will show you if there are any based near to you, although the larger consultancies, in particular, will often undertake work over large geographical areas.

Alternatively, you may wish to search the database on the Chartered Institute of Ecology and Environmental Management (CIEEM) website. CIEEM is the professional body which represents and supports ecologists and environmental managers in the UK, Ireland and parts of Europe. Their members have proven that they are able to work to CIEEM’s professional standards and regularly undertake training to continue their professional development. Using their online members’ directory, you can search for ecologists within certain geographical areas or for specific services. Furthermore, should you have any complaints or concerns over the work conducted, CIEEM has an official complaints procedure that you can use.

When looking to appoint an ecologist, it is worthwhile getting several quotes for comparison. At this point, it is helpful to provide the ecologist with as much information as possible, such as the scope of the project (including detailed plans if these have already been drawn up), the proposed timescale you are hoping to adhere to and any advice that you have already been given (i.e. by an architect or planning agent). Providing them with a map of the area to be developed can also be extremely helpful.

Useful questions to ask at this point are:

  • What is included in the quote and, should additional surveys be required, what are these likely to cost?
  • How long is the work likely to take?
  • Would it be possible to see a draft report and what will be the timescale for this?
  • Are there likely to be other expenses that aren’t covered in the quote, such as mileage or sample analysis?
Important things to consider

• Many protected species surveys have seasonal constraints and can only be conducted at certain times of the year. Because of this, it is important to discuss your requirements with an ecologist as early as possible in the planning process so that you can plan ahead and avoid unnecessary delays.

• Don’t feel like you will be able to ‘get away with’ not conducting the required surveys. Failure to conduct or comply with the appropriate environmental surveys is punishable by law.

• Remember that survey data is not valid indefinitely. Most will be fine up to a duration of 12 months, and some even longer. But any that is more than three years old will definitely need repeating to account for any changes that may have occurred in the interim. If in doubt, it is best to discuss this with your ecologist, planning agent or local planning authority.

Summary

To summarise, when constructing a new building or adding to or modifying an existing one, an ecological survey (or surveys) is usually required to assess its impact on the surrounding habitat and any protected species that may be present. The report(s) generated by these surveys will need to be submitted to your local planning authority as part of the planning process.

To avoid delays with your project it is best to get your ecologist involved as soon as possible so that any necessary surveys can be completed on time – remember that many can only be conducted at certain times of the year.

Book Review: Abundance: Nature in Recovery by Karen Lloyd

Abundance: Nature in Recovery is a collection of essays by award-winning author, Karen Lloyd. Examining abundance and losses in the natural world, Lloyd laments the lack of sight humanity has for the holes we have created. Looking first at artists such as Mary Newcomb, Carry Akroyd, and Daniel Beltrá, the book begins with the struggles of those trying to draw attention to the damaging impacts of human encroachment on the natural world. While many are beginning to understand the harm we are causing, the momentum of our modern society hasn’t allowed us to stop. By recounting a moment when a willow warbler flies into her house, Lloyd compares the fight of individual people against the systems we operate under with the panicked movements of the bird battering against the glass. We, like the bird, have no perception of how to remove ourselves from ‘the world of window frames and glass’ that we inhabit.

Willow warbler by Ron Knight via Flickr

Abundance aims to give a voice to the species and habitats that are often disregarded in the political sphere. Travelling to places such as the Veluwe Forest in Switzerland, the Strathspey woodland in Scotland and the Hungarian Steppe, Lloyd tells the stories of people on the front line of conservation fighting to halt biodiversity loss. The volume of negative environmental news can often be overwhelming, and the author shares her own experience of this feeling in the opening essay. This book is a welcome break, reminding us that conservation success is possible and is taking place right now across Europe.   

Beaver felled tree by Corey Burger via Flickr

Through the exploration of local attitudes to conservation efforts, Lloyd touches on current themes such as rewilding and the return of wolves to the UK. Shifting baselines, where the current generation believes what they are seeing in nature around them is the norm and are unaware of the decline over previous generations, are impacting people’s perspective on the return of previously extinct species. Despite some extinctions being relatively recent, such as the beaver, the general public is unused to living with them. Therefore, they fear the impact these species may have on their daily lives. Worries of damage to livelihood and homes have been exacerbated by misconceptions and scapegoating. Lloyd recounts the concerns people have for the threatened wild salmon should beavers be allowed to remain, despite beavers being obligate herbivores, as well as the attempt to blame beavers for a flash flooding event in Alyth, Scotland. But if we are to allow the natural world to recover from the damage we have inflicted upon it, Lloyd believes that nature needs to be placed centre-stage in everything we do.

Wild salmon by Bureau of Land Management via Flickr

Abundance is an engaging and accessible book, presenting personal accounts of seeing firsthand the impacts of anthropomorphic destruction, riveting natural history stories and shocking data. From the conflict between the need for clean energy sources and the impacts of wind farms on birds to the impact of flood protection on beavers and kingfishers, Lloyd discusses our struggle to find effective solutions to tackle our biodiversity crisis. The engaging and entertaining nature of this book only increases as you read. Comparable to a travel book, each essay is a new adventure in wildlife-rich places. From eighty fragments on the pelican to tales from viewing platforms in the Lake District and the adventure of the 2020 lockdowns, the variety will hold your attention until the very end.

Abundance: Nature in Recovery
By: Karen Lloyd
Hardback | September 2021

 

 

 

 

All prices correct at the time of this article’s publication.

Conservation news highlights from British Wildlife

The conservation news feature has been a fixture of British Wildlife since it first went to print in 1989, and continues to provide a roundup of the most important stories from the world of conservation in Britain and Ireland, covering campaigns, controversies, new initiatives, publications, and policy developments, all accompanied by expert commentary and analysis. 

Here we look back at recent issues of British Wildlife and highlight some of the key stories covered in conservation news, as well as in the main articles, from the past six months. 

February 2022 issue

  • In January, the Environmental Audit Committee issued the output from an inquiry into water quality in rivers. The overarching conclusion was that the ‘chemical cocktail of sewage, slurry and plastic polluting English rivers puts public health and nature at risk’.
  • In 2018, a team from the RSPB discussed in British Wildlife how the Landscapes Review (unpublished at that time) could provide the chance to instal nature at the heart of management of protected landscapes in England. The government responded to the review and opened a consultation; in a recent article David Hampson, Policy Officer at RSPB, analyses the response and highlights opportunities for improvement.
  • On 1st January, Defra issued an updated general licence for bird control in England. This led to further confusion regarding the definition of ‘livestock’ and the timing of when gamebirds are classed as livestock or wildlife.

April 2022 issue

  • The current outbreak of Highly Pathogenic Avian Influenza (HPAI), which was first detected in captive birds in October 2022, is the largest and most severe on record and continues to impact captive birds and a number of wild bird species.  
  • There is an abundance of proposals to build new major infrastructure, housing estates, leisure and business parks on open countryside. A report published by the RSPB in February revealed that there were more than 8,000 live planning applications within 500m of an SSSI in July 2021.

May 2022 issue

  • On 13th April the government announced that the benthic habitats of Dogger Bank and three other Marine Protected Areas are to be legally protected from all forms of bottom trawling and demersal seine nets. 
  • An increasing number of raptors, including a White-tailed Eagle Haliaeetus albicilla in Dorset this spring, have been found dead in recent years, having ingested the rodenticide brodifacoum, an anticoagulant designed to kill rats. In 2020, 23 raptors were found across England, while 25 were recorded in the first half of 2021. In previous years the numbers had been in single figures.
  • The new Natural History GCSE was formally announced on 21st April, 11 years since the idea was first proposed.

June 2022 issue 

  • National Highways, together with the Wildlife Trusts, have launched a new £6 million Network for Nature programme that will create and restore habitats across England.
  • The Levelling Up and Regeneration Bill was introduced in May, and will see the replacement of the current environmental assessment process with Environmental Outcomes Reports. 
  • Somerset Wetlands, England’s second ‘super’ National Nature Reserve (NNR), was declared on 19th May, the 70th anniversary of the creation of NNRs.

British Wildlife is a subscription-only magazine published eight times per year: visit www.britishwildlife.com or email info@britishwildlife.com for more information. Individual subscriptions start from just £40 – you can subscribe online or by phone (01803 467166).

Owl Pellet Dissection

Owl pellets contain all of the indigestible parts of the prey. Image by Gail Hampshire via Flickr.
What is an owl pellet?

Owls feed on a variety of prey; most commonly small mammals but also birds, frogs and other small animals. These prey items are consumed in their entirety and, while the flesh is digested by enzymes, the owl is unable to digest the harder parts of the body, including the teeth, bones, fur or feathers. These indigestible parts are regurgitated as a pellet. Unless they are very fresh, pellets are dry, light and odourless.

In this article we will look at where to find owl pellets and how to tell which species of owl they came from. We will also provide some tips on how to dissect a pellet, how to group the bones into types, and how to identify some of the main species of small mammal that you will find in pellets in the UK.

Where to find owl pellets

Owl pellets can frequently be found wherever owls nest or roost. Good places to search are at the base of tall trees within woodland areas, or in barns or outbuildings where owls are known to roost. Please be aware that you must not disturb breeding or roosting owls in order to collect pellets. Barn Owls in particular are protected in the UK by law under the Wildlife & Countryside Act 1981 and their breeding sites must not be disturbed under any circumstances.

If you don’t have any luck finding your own pellets or don’t have access to places where you might find them, there are several places online where you can order some. Reputable sources in the UK include the Barn Owl Trust and the Suffolk Owl Sanctuary.

What species of owl is my pellet from?

There are five resident species of owl in the UK: Barn Owl, Tawny Owl, Little Owl, Short-Eared Owl and Long-Eared Owl. All of these species produce pellets that are relatively easy to tell apart, particularly if you also know the habitat where they were found. Below is a brief guide to their main characteristics.

• Barn Owl: pellets usually measure 3-7cm in length and are rounded at both ends. They are fairly dark in colour and have a smooth surface.
• Tawny Owl: pellets measure 2-5cm in length and are narrow and bumpy, often having tapered ends. Greyish in colour and sometimes furry looking.
• Little Owl: pellets are fairly small measuring only 1.5-2cm in length. Long and narrow with a soft crumbly texture.
• Short-Eared Owl: pellets are fairly large, measuring 3-6cm in length. Narrow with one rounded end and one tapered end. They are grey and smooth and very lightweight.
• Long-Eared Owl: pellets measure around 2-4cm and are narrow and bumpy. Usually grey in colour.

The most common pellets you will find in the UK are from Barn Owls.

Barn Owl pellet with mounted needle and fine pointed forceps.
How to dissect an owl pellet

There isn’t much equipment you need to dissect an owl pellet, but a few items will make the job a bit easier:

• Mounted needle: this is useful for teasing out fur from around the bones, and moving around delicate specimens. A cocktail stick or needle pushed into a cork will also do the trick.
• Forceps/tweezers: helpful for picking up bones and particularly for removing fur from inside skulls. Forceps with a fine point are best.
• Magnifying glass/hand lens: a small magnifier will allow you to get a closer look at the bones that you find. Jaw bones in particular are very useful for identifying the species and a magnifier will help you get a better look at the arrangement and structure of the teeth.
• White paper/card and glue: it can be helpful to arrange your bones by type onto a sheet of white paper which you can then write on when you have decided what they are and who they belong to. If you would like to make a permanent ID aid you can also glue them onto a piece of card and add permanent labels.

How to identify the contents of an owl pellet

The first thing you will need to do is to tease apart the pellet and separate the bones from the fur and feathers that are holding it all together. To begin with it is easiest to gently break the pellet into several smaller sections then work on each of these in turn. Use your fingers as well as the forceps to carefully tease apart each section, removing any bones and placing them to one side for identification. If your pellet is very hard and dry, try soaking it in water first to soften it.

Once you have all of the bones from your owl pellet, try to group them into types on your sheet of paper. The most common bones you will find are the following:

  • Skulls: for mammals, this consists of the top part of the skull and upper jaw, along with the lower jaw, although this is likely to become detached once you have cleaned all of the fur and other material from inside. For bird species this will include the upper and lower parts of the beak.
  • Back legs: includes the thigh bone (femur) and the lower leg bones (fibula and tibia)
  • Front legs (arms or wings): includes both upper (humerus) and lower (radius and ulna) bones
  • Hip bones
  • Shoulder blades (scapula)
  • Back bones (vertebrae)
  • Ribs

The image below illustrates typical examples of each type of bone. You can also download a useful bone identification sheet from the Suffolk Owl Sanctuary website.

 

The most useful part of the skeleton for identification is the skull and jaws or beak. Bird skulls will obviously be very distinct from those of mammals due to the presence of the beak, so these can immediately be separated out. For the remaining mammal skulls, however, we will need to take a closer look at their lower jaw bones and teeth.

In the UK the most common small mammals you will find in owl pellets are voles, mice and shrews. It is very easy to distinguish which of the lower jaws belong to shrews as they have a continuous line of teeth from the front to the back of the jaw. This is because shrews are insectivores and chew their food, much the same as we do. Voles and mice, however, both gnaw their food, and have a big gap between the long front tooth and the back teeth.

To tell the difference between voles and shrews, we need to take a closer look at their back teeth. Voles have teeth with distinctive grooves down the sides.  In those of a field vole, the grooves run all the way down the side of the tooth. There is also no obvious root. Bank voles have grooves which only run part-way down the side of the tooth and they have two obvious roots, similar to those of a human tooth. The back tooth from a mouse jaw is much smaller when compared to a vole and its structure is much more similar to that of a human tooth. It also has two roots. This sheet from the Barn Owl Trust has a great illustration of the various small mammal lower jaws with size guidelines to help with identification.

Hopefully this article has been a useful introduction to owl pellet dissection and the identification of some of the most common prey species contained within them. If you want more help with identifying all of the bones in your pellet down to species level, the guides listed below are invaluable. Once you have categorised all of the bones you can attach them to a piece of card with permanent labels or arrange them to create a complete skeleton of each species.

Finally, don’t forget to wash your hands well when you have finished your dissection. Any pellet remains can be safely composted.

Further reading

Guide to British Owls and Owl Pellets

This fold-out chart includes colour paintings of the five species of owl permanently resident in the British Isles, shown both perched and at rest. Also included are illustrations and written descriptions of the different pellets that may be found, and a systematic identification key to their contents, including complete skulls, jaws, teeth and other recognisable bones and animal parts.

 

The Analysis of Owl Pellets

This booklet will not only enable you to identify what you find in the pellets of British owls, but also shows how the data may be usefully presented and how to estimate the actual weight of food the birds have eaten.