Five new species of bat for Guernsey

First year of a four-year survey discovers five new species of bat for the Bailiwick of Guernsey

From Phil Atkinson and BTO

The most extensive bat survey carried out by citizen scientists in the Bailiwick of Guernsey using remote automated recorders has found several new species of bat and a new species of bush-cricket for the islands of Guernsey, Alderney, Herm and Sark, as well as collecting almost three-quarters of a million sound recordings of bats, small terrestrial mammals, bush-crickets and audible moth species.

Bats are a poorly understood component of the Bailiwick of Guernsey’s fauna, despite making up more than half of the terrestrial mammal species. Guernsey’s Strategy for Nature provides a clear direction to establish baselines for key biodiversity groups to provide government, other policy makers and practitioners the information required for good decision making. Learning more about the numbers and species of bats locally contributes to this, as they are key species for indicating the condition of the islands’ environment.

This research is being carried out through the Bailiwick Bat Survey: a four-year partnership project between the British Trust for Ornithology (BTO) and the States of Guernsey’s Agriculture, Countryside and Land Management Services (ACLMS) with coordination by La Société for the 2021 survey. Over 200 volunteers signed up to survey one or more of the 360 500 x 500m survey squares and borrow a detector for 4-6 nights from one of our Bat Centres. Working with this network, static acoustic bat detectors were deployed during 2021 over a long survey season (April to October). A total of 2,221 complete nights of recording effort was achieved across 611 different locations, providing the first extensive baseline data for bats for the islands. The Alderney Wildlife Trust and La Société Serquaise organised the surveys in Alderney and Sark, and the Guernsey Biological Records Centre hosted the website and will be the repository of the data.

Over 1.5 million sound recording files were collected by volunteers. These were initially fed into the BTO’s Acoustic Pipeline, where they were automatically identified to species using machine learning. Following an additional process of manual verification, these were found to include 710,260 bat recordings, and 8,211 small terrestrial mammal recordings. In addition, several species of bush-crickets and audible moth species were recorded, revealing the presence of 11 bat, five small mammal, six bush-cricket and two audible moth species.

Five of the 11 species of bat had not been recorded previously in Guernsey, and included serotine, whiskered or Brandt’s bat, Leisler’s bat, common noctule and lesser horseshoe bat. Serotine was also new for Alderney and Sark. A new species of bush-cricket, large conehead, was also found on Guernsey, Alderney and Lihou, which is the first record of this species in the Channel Islands.

Sarah Allez, the Bailiwick Bat Survey Coordinator at La Société said, “Undertaking such a large survey of the islands was only possible because of the large numbers of volunteers who put out detectors for us. The enthusiasm shown by volunteers has been amazing and the survey has really highlighted how some species rely on buildings for safe roosting areas and natural habitats for feeding.”

Julia Henney, Biodiversity Officer at ACLMS said, “Such a widescale survey has given us an insight into how this often overlooked group of nocturnal mammals uses Guernsey’s built and natural environment. With three more years to go we will have a comprehensive understanding of the habitats that are important for all the bat species that occur in the islands.”

Dr Phil Atkinson, lead scientist on the project, said, “The current dataset of 710,260 bat recordings has been very valuable in adding to our understanding of patterns of occurrence and activity of bats across the Bailiwick of Guernsey, but it also adds to our understanding of some other species groups that were recorded as ‘by-catch’ during bat surveys, and shows the power of citizen science. My thanks go to the 200+ volunteers who dedicatedly deployed the detectors, without which this project would be extremely difficult to carry out. I look forward to seeing what we might discover next year.”

Download the report Bailiwick Bat Survey: 2021 season report here 

Sheep on Les Blanches Banques

Plans to return sheep to the sand dunes of Les Blanches Banques and grazing to revitalise the grasslands

By Tim Liddiard

Les Blanches Banques

The sand dunes of Les Blanches Banques, set in and around St Ouen’s Bay in St Brelade and at the heart of the Jersey National Park is recognised biologically as being one the richest sites of its kind in the Island and has been described as ‘undoubtedly one of the premier dune systems in Europe for its scientific interest’. As the most extensive area of sandy soils in Jersey, the dunes support good populations of many animals and plants on the Island that are not found elsewhere.

During the Medieval period, the dune grasslands were used for sheep grazing and stacking sea weed to dry, the latter was used as fertiliser, or was burnt on the dunes to produce potash.

In the absence of a grazing regime on the sand dunes in recent years, due to the processes of seral succession it is evident that the important grasslands habitats are being subsumed by the spread of mixed scrub.

Currently an amount of grazing is being provided by rabbits but not at a level sufficient to halt or reverse the loss of the important dune grasslands, a key habitat in the Biodiversity Strategy for Jersey 2000 and home to a number of notable plants and a host of other wildlife.

A total of over 400 plant species have been recorded on Les Blanches Banques, many being unique or special to our shores.

Some of the plants found on the sand dunes which are recognised as being of scientific interest include the lizard orchid, with its flower resembling its reptile namesake; the dwarf pansy, in Great Britain only found on the Isles of Scilly and the Channel Islands, the heath dog violet which is Near Threatened in the UK and the sand crocus with its diminutive mauve flower.

Amphibians and reptiles enjoy life on the sand dunes, which harbours five of Jersey’s seven species. Palmate newt and slow worm are present but a visitor from mainland Britain will perhaps be more excited by the exotic looking green lizard with its emerald and aquamarine colouring. Also the western toad is found here rather than the common toad of Britain and northern Europe. The grass snake can be seen here on occasion, they are one of Jersey’s rarest animals and the sand dunes remains one of their few strongholds.

The blue winged grasshopper, the firebug, the Queen of Spain fritillary butterfly, the lesser bloody-nosed beetle, exuding a minute drop of blood when alarmed and the sand bear wolf spider which ambushes its prey from the entrance of its burrow are all invertebrates of particular interest to Jersey and our sand dunes.

 

The skylark, a ground nesting bird with an enchanting song is in decline across Europe and is a local Action Plan species, as is the stonechat, a bird whose call resembles the sound of two pebbles being knocked together. The chough, one of the great successes of the Birds On The Edge partnership is known to forage on the sand dunes and the conservation of the grasslands along with the addition of dung and its associated invertebrates will help provide these wonderful birds with an ongoing food source.

Grazing Plans

It is accepted best conservation practice to graze stabilised dune systems with livestock and the purpose of this project is to trial the grazing of Manx loaghtan sheep in scrub habitats and adjacent grasslands. These habitats have an abundance of burnet rose and other plant species which are becoming dominant over the more desirable dune vegetation which includes orchids, dwarf pansies, sand crocus and much more.

The area selected for initial grazing trials is on the escarpment north of La Moye Golf Club in an area known as Le Carriere. A combination of winter and summer grazing is the ideal, providing the chance to control holm oaks and other evergreens during the winter months and stripping foliage from other target plants (including privet, blackthorn and burnet rose) during the summer. Throughout the project the sheep’s food preferences will be constantly monitored with the hope that they will target the more undesirable plant species.

The sheep are planned to be on site from late February until May 2022.

Importantly, this area currently attracts a low level of public access and will not have a large impact on where people are able to walk.

Our thanks are extended to La Moye Golf Club for allowing the fenceline to tie into their existing fence which allows for a larger area to be grazed.

Benefits to habitats

• To prevent and reverse grassland succession towards mixed scrub within areas being grazed
• To maintain and increase plant species diversity within these areas and encourage some bare ground
• To introduce and maintain age mosaics throughout gorse and scrub dominated communities
• To encourage the reinstatement of species rich grassland especially in grassland ‘islands’ which are contained within the scrub area which are being lost to scrub
• To trial which plant species the Manx loaghtans forage on the most, thereby identifying their effectiveness in the control of scrub intrusion onto dune grassland habitats.

Benefits to species

• To provide bare ground for seed germination of dune grassland associated herbs and grasses
• To provide bare ground for associated invertebrate species
• To identify the effects of Manx loaghtan foraging behaviour on particular plant species , notably burnet rose, bracken, privet and blackthorn
• This area is recognised as being important for grass snakes and the creation of grass glades amongst the scrub will provide welcome basking areas for them
• There is a strong association and reliance between foraging choughs and short grassland, especially when grazing livestock and their dunging encourage the presence of dung beetles.

Chough report: January 2022

Winter sun at Sorel. Photo by Liz Corry.

By Liz Corry

New year new start. At least for Vicq our breeding female who was ditched by her partner for the ‘other woman’. We have seen Vicq allopreening Pinel a wild-hatched male from 2020. This could mean a new pairing for the 2022 breeding season. She has lost the nest site in the quarry, and we are not clear on where she roosts. In 2019, her first nest attempt was out on the cliffs at Sorel. She might try again if she can hold on to Pinel.

Another new pairing is emerging between two wild-hatched birds Danny and Jaune. The female will be coming into breeding age and looking for a suitable site to lay. We will be eagerly following the progress of this pair.

We have only received a few public sightings this month, all from known foraging sites. Maybe the flock are thinking it’s time to knuckle down and work on getting through winter. There is not much point in them investigating new sites at the moment considering how waterlogged it has been. 

Several fields in Grouville become flooded at this time of year. Photo by Liz Corry.

Aviary maintenance

With the assistance of Neil, Government Countryside Ranger, we transported the Henchmen ladder to Sorel to repair the netting. The work took a couple of days to due to a lot of faffing around adjusting all four legs each time the ladder was repositioned. The joys of working at height on uneven surfaces. We also had to deal with the interchangeable weather. From sun, to fog, to rain, and back to sun. 

A feeding stand temporarily turned into a Henchmen workstation. Photo by Liz Corry.

The fog actually increased the visibility of the rips in the netting. Photo by Liz Corry.

We started replacing the rotten steps to reach the hatches. Next month’s job looks set to be replacing the hatches themselves as the wood is giving way. One has already had a quick patch-up job as we have been trying to shut in a couple of birds to replace leg rings.

The first attempt failed when the hatch broke and scared off the flock. The second attempt the following week failed because we had lost their trust…and it started raining.

Nest monitoring

We still need to replace a couple of nest boxes in the quarry. Ronez have been experiencing technical difficulties and staff levels impacted by contact tracing. It has somewhat worked in our favour, as two data loggers arrived in the post this month for monitoring temperature and humidity levels in nest boxes.

Blue Maestro Tempo disc records temperature and humidity. Photo by Liz Corry.

The Blue Maestro Tempo disc stores data and sends it via Bluetooth to a smartphone app. Battery life should last the duration of the nesting season. We can fit them in the boxes now before installing the boxes. There are no glowing lights to distract the birds so hopefully they will not interfere. 

‘Extra-curricular’ activity

I decided January wasn’t challenging enough so ramped things up by attending a Data Analysis with R course and threw in a BIAZA-IUCN workshop on native species conservation to the same week.

I’d like to take this opportunity to apologise to anyone who tried to have a conversation or ask me a question that week. Head to any R forum chat site to appreciate why I had the appearance of a recently lobotomized patient each time I emerged from the office.

That being said, I highly recommend the online course run by Eco-Explore.co.uk for anyone who needs to use R. They make it less painful than it sounds.

Excerpt from Thomas, R., et al. (2017) Data Analysis with R Statistical Software.

The overall aim of the BIAZA-IUCN workshop overall aim was to help inform a new framework for a more collaborative and holistic approach to UK native species conservation, linking stakeholders and identifying priority gaps.

There is already a lot of work going by zoos and aquaria in the UK to support native species. Just take a look at the incredible pine hoverfly breeding and restoration work by the RZSS. And of course, our very own chough and agile frog work featured in the Top 10 BIAZA list.

We could achieve a lot more, with greater success, if we work together as institutions and more closely with stakeholders.

A way of assisting this is to document what you have done, both the successes and the lessons learnt. We recently published online at PANORAMA, a partnership initiative to document and promote examples of inspiring, replicable solutions across a range of conservation and sustainable development topics, enabling cross-sectoral learning and inspiration (I copied that bit). It is led by IUCN and a German organisation called GIZ. Other partners include Rare, UN Environment Programme (UNEP) and the World Bank.

Click here to read the case study for Jersey’s choughs.

 

February volunteer activity

Sunday 13th February 2022 – Mourier Valley, St John 10.00 – 12.30

From Jersey Conservation Volunteers

Task Join the National Trust for Jersey’s Lands team on Sunday 13th February to help maintain some of the many trees planted over the last two years, with the opportunity to plant some more. The activity involves tree planting and maintenance at Mourier Valley. This scenic area overlooks the valley with views of the northern coastline. https://jerseytreesforlife.org/

If you have any questions, or if you wish to be added to the Wild About Jersey email list, please contact either Julia Clively (tel: 441600; j.clively@gov.je) or Jon Parkes (tel: 483193; jon.parkes@nationaltrust.je).

COVID 19 You will need to book a place to join this task Jersey Conservation Volunteers Event Tickets, Sun 13 Feb 2022 at 10:00 | Eventbrite

Please follow the latest guidance on www.gov.je and to help keep us all safe we ask that you perform a Lateral Flow Test before joining the task.

The site Meet in the car park on La Rue de Sorel. Jersey Phone Directory Map 3 R2 Google maps here 

Time 10:00. It will be a short walk to the planting site. We will finish work at approximately 12:30 to give us the chance for a cuppa.

Parking There is parking close at Sorel Point.

Tools needed We will provide some tools and gloves but if you have any of your own then feel free to bring them along.

Clothing needed Please dress for the weather and wear sturdy footwear. We can supply a pair of gardening gloves if you don’t have them.

Children All are welcome, although we do ask that volunteers under 16 years of age are accompanied by an adult. Due to the uneven ground, a reasonable level of fitness is required.

Refreshments (Please make sure you bring your own mug or reusable cup) A welcoming mug of tea and cake will be available to all who join us for the morning, which are kindly provided by Kim.

See you there!