Chough report: January 2020

New year, new decade, what will 2020 have in store for the choughs? Photo by Liz Corry.

By Liz Corry

New year, new start, new friends, with just a few old problems needing innovative solutions. January has been very busy behind the scenes. Flavio and volunteer Jane have done a great job making sure things run as smoothly as possible. Luckily the choughs have also been co-operating keeping themselves alive and well! 

Charity plea for wetsuits for choughs

Don’t think this needs any further explanation.

Jersey choughs made a public plea for wetsuits. Image by Liz Corry.

…apparently the boss is saying it does.

Last month we discovered rips in the aviary netting where the material has been rubbing on the new central scaffold pole. The pole was put in last March along with brand new netting so you can imagine our dismay on discovering the problem.

Holes have been appearing in the netting where it rubs against the metal frame. Photo by Liz Corry.

The metal pole has to stay because it stabilises the tunnel framework. We can sew up the holes. How do we stop the wear and tear?

With wetsuits! I came up with the idea whilst trying to think of suitable padding material to reduce friction. Traditional yellow foam used on scaffold structures is not suitable; birds will peck at it and ingest foam. Neoprene is more robust and should be able to cope with whatever weather Jersey throws at it. 

Cue second light bulb moment. I contacted Durrell’s Charity Shop to see if they had any wetsuits in stock. Angie and her staff were very helpful. By sheer luck, five were donated after I put in the request. Flavio set to work cutting them into strips.

Dismembered bodies…of wetsuits being used to repair the aviary. Photo by Liz Corry.

The States Rangers kindly volunteered to transport our Henchman ladders up to Sorel (they promised to bring them back too!). Flavio and I could then set to work securing the neoprene to the scaffold.

Henchman ladders for safely working at height. Photo by Liz Corry.

Old neoprene wetsuits cut up and fitted to scaffold to reduce friction with the netting. Photo by Liz Corry.

Whilst on the ladders, we noticed another problem with the netting. This time where it joins the timber frame and hoop on the end. More neoprene was added, gaps closed off, frayed ends trimmed and battened down.

Tension in the netting caused some sections to pull away from the timber joins. Photo by Liz Corry.

Netting had frayed and tension, increased by the wind factor, was resulting in gaps along the joins. Photo by Liz Corry.

Gaps in the netting were closed off with cable ties then neoprene fitted over the top to prevent further fraying. Photo by Liz Corry.

They say things happen in threes…we also found new rodent holes in the netting on the last day of fitting the neoprene. Something digging inside the aviary looks to have exited via the netting. 

Rodents at it at again chewing through the netting. Photo by Liz Corry.

Only time will tell if the neoprene works. I will be keeping an eye out for mildew. Hopefully the wind and/or sun exposure will mean it dries out pretty quickly after any rains. We also need to see if the birds are happy perching on neoprene. Thirty of them lined up along a dry stone wall on the afternoon we finished the work (zoom in on the camera phone photo below). Coincidence or the answer to our question? Let’s go with the former for now.

An unusual sight of thirty choughs lined up along a dry stone wall apologies for poor quality phone photo). Photo by Liz Corry.

Gearing up for the breeding season

Tensions are building between the choughs, as pair bonds are reinforced and new ones forged. If you spend some time at Sorel you might witness a few squabbles. They can look pretty intense, but generally over quite quickly with nothing hurt other than pride.

National Trust fields at Sorel shared by choughs and sheep. Photo by Liz Corry.

Several still visit Les Landes and other areas on the north coast. Trying to identify leg rings, and, therefore, which birds, is still problematic. More so when dealing with Jersey cows. Their friendly curiosity is appealing. Their stubbornness when trying to get them to move out of your line of sight not so appealing.

Jersey cows at Les Landes racecourse blocking my view of six choughs feeding 100 metres away. Photo by Liz Corry.

The choughs main focus will soon switch from food to nesting. Preparations are under way in the quarry to carry out maintenance on the nest-boxes used last year. Once again Ronez are being very helpful. Even roping in family members!

Toby’s father Alain Cabaret has a joinery business (A J Cabaret) and very kindly created a prototype nest-box at no cost to the project. The design is based on Oliver Nares’ successful barn nest-box used in Ireland with wild choughs. Oliver provided schematics which Alain then modified for use in a quarry building with guidance from Toby. There is a lid allowing access for ringing chicks with potential to fit a nest camera if a power supply is available.

Entrance of the new nest box is designed to deter other species from using it. Photo by Liz Corry.

Alain used Tricoya extreme which is supposed to be more robust than marine grade ply. Tricoya is more expensive; roughly £100 from one nest box, even after a generous discount from Normans building supplies. However it should last twice as along. Once we find funding we can set to work building another two; one to improve Green and Black’s success rate and one to replace Percy and Icho’s broken home.

Side profile of the new nest-box for the quarry building. Photo by Liz Corry.

New roost site on the north coast

A new roost site has been located at Crabbé thanks to an opportune sighting by the Jersey bird ringers early one morning. Whilst out ringing by the conservation crop fields, they spotted three choughs leaving a farm building heading east towards Sorel.

Flavio and I then staked out the area during roosting time for the next few days. There is a pair roosting at this site. They tend to fly in from the direction of Sorel and go straight to roost either as soon as the sun sets or a few minutes after. No dilly-dallying about in the grazed fields (horses, sheep, and pigs!) or on the roof tops.

We have been treated to some pretty spectacular sunsets. None of which have helped identify leg rings since blue become black, red might be orange, but if you wait a few more seconds that too might look black! 

Sunset at Crabbé. Photo by Liz Corry.

We think we know which pair and they stand a good chance of having their first nesting attempt in the same area. There is a slight catch. Planning permission has been granted at this site. Good news is that the owner is supportive of the choughs and has mitigation plans in place for other species. The development will remain agricultural rather than housing etc., but construction may disturb any nesting attempts. 

A pair of choughs have been roosting at Crabbé for the past few months. Photo by Liz Corry.

We need to develop a working relationship with the landowner and hopefully provide the chough pair with the support they need to raise the first Crabbé chough chicks! I suspect this situation will be repeated as the birds start forming more and more territories away from Sorel. 

Transferable skills

Another species spreading around the island, and not in a good way, is the Asian hornet. I recently spent some time helping Jersey’s Asian hornet team develop radio-tracking skills as a tool to find nests. Locate the nest, destroy the nest, control population growth. 

Dr Peter Kennedy, University of Exeter, is a hornet tracking ‘guru’. He developed the method and came to Jersey last year to demonstrate tag attachment and tracking to Alastair Christie, Asian Hornet Co-ordinator.

The team now have radio tags they can deploy in the field so I was asked to share my knowledge and experience with radio-tracking in Jersey.

If you think you spotted a hornet or indeed a nest please refer to the Government advisory website for identification tips and relevant contact details.

Some of the Hornet Team getting to grips with radio-tracking. Photo by David Ferguson.

Presenting at BIAZA’s Conservation and Native Species Conference

For the past few years I have attended BIAZA’s Native Species Conference listening to talks from a wide range of conservation projects associated with zoos. This year I braved the podium and gave a presentation about the chough project and lessons we can share with others.

BIAZA combined it with their Field Conservation conference for 2020 under the theme ‘Rewilding’. This meant subject matter ranged from pine martens in the Forest of Dean to penguins in South Africa. 

Just a few of the talks at the BIAZA conference held at Chester Zoo. Photos by Liz Corry.

The three day event was held at Chester Zoo. Delegates took part in workshops and had a guided tour of the zoo’s new nature reserve. We even got to muck-in helping repair fencing.

Sarah Bird, Chester Zoo, giving a guided tour of their nature reserve backing onto the Shropshire Union Canal. Photo by Liz Corry.

Growing up in the northwest it was nice to hear about the amazing work on the Manchester Mosses project. Peatland restoration work involving Chester zoo, local Wildlife Trusts, and several other partners has seen the return of plants and invertebrates decimated by peat extraction, property development, and industry.

The rare large heath caterpillar raised at Chester Zoo for release back into Greater Manchester, Merseyside, and Lancashire. Photo by Chester Zoo.

I’m pleased to say the chough presentation was well received. Hopefully I did my bit to raise the profile of the species, our work, and of course Jersey!

Croeso i Gymru

Always one to maximise my time on the mainland, I headed over to Anglesey, Wales, prior to the BIAZA conference and met with RSPB staff working with choughs.

The sight of choughs flying around South Stack lighthouse is common – just not on this day. Photo by Liz Corry.

Having studied in Wales, it wasn’t the language I found baffling, but the names of the choughs! Until they explained it to me. ‘Mousetrap’, a breeding female in the area, is named after the rock climber’s route known as Mousetrap Zawn. 

The rugged coastline of Anglesey provides perfect nesting for choughs. Photo by Liz Corry.

South Stack offers perfect habitat for choughs; grassland, dramatic cliff tops, wind swept. Explains why their clutch sizes are so large with hatching success to match.

On clear days you can see Snowdonia from the RSPB office at South Stack. Photo by Liz Corry.

The team’s success was acknowledged last year with the coveted ‘Golden Spade Award’ for “producing lots of chough chicks”. 

Joking aside there is a lot we can learn from them in terms of habitat management in Jersey and population dynamics. In turn, we hope to reciprocate sharing the knowledge we have gained.

We discussed two potential collaborative research areas; GPS use for monitoring home range, habitat use and energy expenditure, and isotope analysis of wild diets. Exciting times ahead for 2020!