In May this year, Jersey’s States Assembly declared a Climate Emergency (see subsequent report here). As you know, trees and hedgerows play a vital role in capturing and storing atmospheric carbon dioxide as well as providing an important habitat for our local biodiversity.
October has seen a distinct dip in temperatures and a rise in the amount of rainfall and blustery weather. The number of choughs at the supplemental feed has been just as varied. Often the two are linked. Birds prepare for bad weather by filling up on calories. As the days get colder the choughs spend more time around the supplemental feed site. Some that have been independent all summer, like Xaviour, are now returning because wild supplies are running low out west.
On days when its constantly tipping down you might not find any choughs around the aviary – they are sheltering somewhere like the quarry or cliff crevices. Or, you arrive to find a dozen very angry choughs flying out of their aviary shelter cursing your presence, waiting to return the second you leave.
On drier, calmer days, the birds are out making the most of the sunshine. We had six records sent in by the public this month. Two reports from Alison Hales, Director of Paradise Park, whilst over here on holiday. One tourist who should definitely know what a chough looks like!
Chough flying over Sorel. Photo by Shaun Gillard.
Two choughs were spotted foraging on grassland at St Ouen’s Pond and Kempt Tower. There have only been a few sightings in this latter area since the first release in 2013. Enough to suggest this small patch of land in the bay is alluring to choughs but quite how important it is we don’t know.
Spotting one or two choughs can be tricky. A dozen on the other hand… A resident near Les Ormes reported twelve noisy choughs flying overhead in a southerly direction. This is the first record for 2019 of choughs in St Brelade’s parish.
We will be adding a link on the website to the list of choughs out and about in Jersey. This is in response to a suggestion made by a local resident. If you manage to see the leg rings (quite a challenge) you will be able to identify the bird and discover a bit of. Hopefully leading to more detailed records
A chough at Grosnez reported and photographed by local resident Chris Eve.
Catching up with the choughs
One of this years juveniles, PP044, was caught up and treated for a suspected Syngamus infection this month. This naturally occurring nematode tends to cause problems every now and again even though it is probably present all year round.
Our ability to treat affected individuals has contributed to the success of the reintroduction. I am pleased to say that PP044 responded well to her worming injection and continues to fly free around Jersey.
As a side note we also caught up Black, one of the original females, when we trapped PP044. Black needed a replacement plastic leg ring. Once this was fitted she was released and flew off to rejoin her partner.
Numbers down again
Ronez staff found a dead chough in the production area of the lower quarry on 26th October. Leg rings allowed for instant identification of Lotte, a wild-hatched female just under eighteen months of age. She had not shown any signs of ill health and was seen the day before at Sorel.
A bit of a mystery for the vet carrying out the post-mortem examination. We are waiting on lab results before determining cause of death.
Seasonal roost checks
Evening view from Sorel cliff path with Sark on the horizon. Photo by Liz Corry.
Several roost checks were carried out at the end of October to determine which birds, if any, roost at the aviary. It is helpful to gauge how dependent the choughs are on this structure especially since the population has grown.
We also want to see if there is any significant change to numbers once the clocks fall back an hour. Historically we have seen a rise in the numbers of birds using the aviary in winter. This may be linked to certain quarry roosts being disturbed by artificial lighting and work there continuing when the sun sets before 5pm.
Getting answers has not been easy. Camera traps inside the aviary have had limited results. We only have two to start with and one mysteriously stopped working. To cover every potential location, Flavio has been re-positioning the camera each night and checking through the footage the following day.
Combining this evidence with observational data we have managed to gain… very little knowledge. There is definitely one chough roosting by herself in a box. The jury is still out as to whether the external roost boxes are being used and if we have a few more choughs at the aviary. It does appear, however, that fewer choughs are using the aviary as a roost site than in previous years. A step in the right direction.
The chough pairs have been at it again. With more plot twists than a daytime soap opera, we now appear to have three new pairings. Two of which are to the detriment of others.
Toby, a young male from the quarry, has been seen preening Aude a three-year old female. Hopefully this pair will make it through the winter and have their first go at breeding next year.
Rather annoyingly (from our viewpoint), Pyrrho has been seen with Betty. At first it just seemed coincidental that they were at the same feed stations. Progressing to suspicious and ending with definitely a pair when she was seen preening Betty all afternoon.
Two things to note are (1) Betty is a male and (2) Pyrrho fledged two chicks this year with Skywalker. So where the heck is Skywalker? He hasn’t been seen at the feed for over a month. Likewise Betty’s other half has not been seen in a while. They were not a breeding pair so a little more acceptable that they have parted.
Not content with one drama, we started noticing Xaviour at the feeds and in a fairly regular fashion. She is one half of the Plémont pair. The male is unaccounted for. We have noticed Xaviour feeding from the same food bowl as Beaker a young male. Coincidence or a completely calculated move?
It might seem a little early, but we have started planning for the 2020 breeding season. Working alongside Ronez’s Toby Cabaret we have identified three nest sites in the quarry that need a little TLC in order to ensure their continued success.
One nest-box is looking a little worse for wear. Not surprising given that it’s exposed position means it takes a battering from the winds and rain. It is now a health and safety risk to workers below and Toby’s team will replace the box with a more secure, longer lasting box.
A little lopsided, this nest-box is now a safety risk after taking another battering from the storms. Photo under license by Liz Corry.
As part of this ‘renovation’ work we are trialling a different design of nest-box. One that was brought to our attention a few years ago by a family in Ireland.
Incorporated into their barn conversion was a novel nest-box design to accommodate a resident pair of chough. The pair successfully raised young the following season. Clearly a winning design and one that will hopefully work in the quarry.
Bespoke chough nest-box incorporated into a barn conversion in West Cork, Ireland. Photo by Oliver Nares.
We have to mention the Go Wild Gorillas who departed the Island trail in a blaze of glory. The million dollar statues* were on display at Jersey Zoo for one last time before the auction. Without discrediting all the amazing artists, our favourites had to be Dia de la Exctincion andI-Spy for featuring a red-billed chough in their design!
*actually the auction raised more like 1.5 million given the exchange rate!
Tim Sutcliffe’s Dia de la Exctinction gorilla design (top left) included a chough as did I-Spy designed by Jersey artist Gabriella Street. Photos by Liz Corry.
The 5th International Chough Conference was held in Segovia, Spain from the 3rd to 5th October. Held at the Palacio Episcopal building adjoined to Casa de Espiritualidad San Frutos. A very religious affair! And very inclusive events with delegates from Spain, Portugal, Italy, Germany, Switzerland, France and all around the UK. And Jersey!
There were two days of talks focused on red-billed choughs and yellow-billed (Alpine) choughs and a field trip to Hoces del Duratón Natural Park on the final day. Being the chough geeks that we are, the evenings were spent staking out chough roosts in ‘downtown’ Segovia. More on that later.
Question time after each set of talks.
Segovia is a 25 minute train journey north of Madrid and famous for it’s gothic cathedral, roman aqueduct, and Disney-esque Alcázar Palace. It also happens to be home to a large population of red-billed choughs.
A census carried out this year by José González del Barrio and his team recorded 123 choughs roosting in the city. They seem to have a penchant for architectural masterpieces; its not hard to see why. The cathedral is home to half the population with the alcazar and churches accommodating another 30%.
Segovia Cathedral is home to half of the city’s red-billed choughs. Photo by Liz Corry.
It stands to reason that they also have a considerable number of nest sites in Segovia. José’s team recorded 94 nests this year ranging from natural caves to guttering in the cathedral. Bell towers seem to be a particular favourite.
It is not unusual for Spanish choughs to nest in man-made structures, but researchers have noticed an increase in numbers of birds switching from natural mountain caves or crevices to these urban sites.
Just outside of the city (1-3km) there are cereal crops, fallow fields, and grazing cattle and sheep on land they refer to as ‘wasteland’ i.e. can’t grow commercial crops. These provide foraging sites for the choughs (and jackdaws). This is probably why the urban areas are more appealing to raise young rather than up in the mountains where temperatures fall below zero.
However, there is a rather unappealing element to urban living. I’m not referring to the flea-riddled stray cats that prowl the cathedral like a gang of hooded youth. Although cats and rats do predate the birds and eggs.
Cathedral cats prowl the chough territories but don’t be fooled, its hiding a flick knife somewhere. Photo by Liz Corry
The problem is Segovia’s human inhabitants and their dislike of pigeons. Pigeons roost and nest in the same places as choughs. So when someone puts up a deterrent to stop pigeons pooping on an historic monument, it also stops the choughs. Nine nests failed this year due to human disturbance. The worse cases seeing chicks and/or adults blocked in and starving to death.
Blocking off building access to combat pigeon problems can be fatal to choughs.
This behaviour is largely due to a lack of awareness over choughs in general. One reason why organisers selected Segovia to host the conference. Our presence in the city (especially on the roost visits) gives the choughs some ‘air time’. We also had local government officials sit in on the talks. Hopefully public attitudes will change towards choughs. The real challenge will be how to pigeon-proof a structure whilst still giving access to a similar sized species.
City life or country living?
Despite the perils of city living, the choughs have been switching their country cliff-side dwellings for urban development over the last 10-15 year in central Spain. Guillermo Blanco presented data that showed the number of cliff nesting pairs had dropped by 180 pairs over a twenty-eight year period. Switching limestone or clay cliffs for farm buildings and human dwellings.
Jesús Zúñiga had a similar tale to tell in the Sierra Nevada National Park of southern Spain. The chough population has declined by 60% compared to data collected in 1980-1984. This also coincides with an increased use of buildings for roost and nesting.
Choughs in central Spain are switching from cliffs for buildings when it comes to nesting and roosting.
Some choice of nest sites may look familiar to Birds On The Edge readers. Others are a little more suited to the pages of Homes & Gardens magazine.
Many of the buildings the birds are choosing to nest in are abandoned and nowhere near as intricate as the cathedral and churches of Segovia. Ledges and boxes have been erected by conservationists to support nest construction. They are seeing some amazing results.
As eluded to earlier, predators are more of a problem in these areas. Cats, rats, pine marten and genets. A team from Sociedad de Ciencias Aranzadi have come up with a genius idea – “ugly nests” (patent pending). They have used reclaimed materials such as water containers (too slippery for the mammals to grip) and installed them so they are out of reach from predatory paws.
Installation of artificial nests built with recycled materials.
Wild chough chicks reared in reclaimed artificial nests.
The team were so proud of their ugly nests that we were treated to a demonstration of how easy it is to make one (we had the priest on standby if it all went wrong). We even had an auction with the winning bidder becoming the proud owner of a bespoke ugly nest!
Practical demonstration of how to make a chough nest-box from a water container.
Food availability for choughs
The main reason for the ‘cultural shift’ in Spanish choughs has been the change in agriculture surrounding the limestone cliffs and gorges. Irrigation of the land for maize and fruit growing instead of traditional dry cultivation means a reduction in suitable foraging habitat for the birds.
Places like Segovia on the other hand have livestock grazing within a kilometre of the city walls. This is perfect foraging habitat for choughs (and several hundred jackdaw).
Cattle grazing outside Segovia’s train station provides perfect foraging habitat for choughs and jackdaws.
We know dung is a favourite food source for UK choughs. Gillian Gilbert (RSPB) explained how the Scottish birds particularly like to rummage through dung between July and October in search of invertebrates. In the 1980s, choughs were finding lots of beetles from the Aphodius family. Nowadays, Aphodius numbers have declined and the choughs are more reliant on species of Geotrupes beetles. So what is the problem? Well Geotrupes are soil-boring dung beetles, they drag the dung down into the ground, whereas Aphodius live in the dung. The birds have to work more to probe soil compared to dung which means Geotrupes have less nutritional value.
Eric Bignal feeding choughs in Islay as part of their conservation management.
Food availability (or lack thereof) was a common theme across all countries. In the UK, the Islay choughs began receiving supplemental food eight years ago when researchers noticed a population crash. This extra food, provided by farmers and chough-champions Eric and Sue Bignal, is crucial during the months of September and October.
In the past few years, several of the Cornish birds have been visiting garden bird feeders to score some free food. This may be more opportunistic than essential for survival, but certainly something researchers should keep an eye on in case things change.
Yellow-billed (or Alpine) choughs are known to be opportunistic feeders. Mention choughs to anyone who skis in the Alps and they will probably regale tales of over-friendly, black birds hanging around their restaurant table. Alpine choughs have a broader diet then their cousins. In winter, as temperatures drop they start to forage on juniper berries, seeds, and après-ski leftovers.
Alpine choughs foraging. Spain 2014. Photo by Glyn Young
Cristina Vallino, University of Turin, has undertaken a novel approach to observing the feeding behaviour of these birds around ski resorts. Using the free-access public webcams from ski-resorts in three different Alpine countries she has clocked up 13,704 recordings and analysed flock size, stay time, food intake, vigilance distance and flushing distance. She then combined this with genetic studies of the diet to determine variation in diet. Her concerns for the Alpine chough are the long term effects of eating leftovers. Will this ‘fast food’ be effecting their health?
Conservation of European choughs can be a little tricky compared to the UK because the birds can travel long distances. For example, in some years individuals roosting in Segovia may nest in Madrid. Subsequent juvenile dispersal from those nests plays an important role in range expansion. Not just moving within country but between countries too.
Personally speaking, the two most anticipated conference presentations focused on the first use of solar-powered GPS tags on choughs. One on an Alpine chough in Aragon, Spain, the other on red-billed chough in central Spain.
Both studies used transmitters built by a Lithuania company, Ornitrack. The tags transmit data using the 3G mobile network. So as long as you have coverage you can receive data anywhere in the world…roaming charges apply. No joke – just ask the Russians!
Solar-powered GPS tag on a red-billed chough.
The tag is solar-powered which explains the bulky size; the panel needs to be above the feathers in order to charge. The weight of the tag requires harness attachment rather than just gluing on to the body. Juan Manual Pérez-Garcia and his team fitted harnesses to six birds this summer and had some interesting results.
One bird covered a distance of 173km in two days. Another flew 85km on its first flight (in under 3 hrs) then took another 15km journey before settling down for 12 days. Sadly it was then predated by a booted eagle. They know this because an accelerometer fitted in the tag gives an activity pattern. You can detect feeding events, roosting events, and sadly the shaking around and eventual immobility from a predation event. And then the carrying off to the nest to feed the eagle chicks event!
Data from the GPS can provide information on whether the bird is in flight or at rest. Or caught by a booted eagle!
These studies are in their infancy stage. A lot of work is needed looking at the welfare implications of tag attachment. Cost is a small hurdle to overcome considering each tag is about £1,200 plus a data transfer fee. There is definite potential and something we are keen to explore in Jersey.
Future prospects for choughs
The scope of work and tireless dedication evident from everyone in the room (any associates that could not be there in person) is promising for the future of choughs. Whilst classed as least concern, due to their global range, the species appears to be in decline. By sharing data, collaborating on research, and undertaking well-planned translocations or re-introductions we will hopefully halt any further decline. In the process, as several talks showed, this can have a far wider impact for global biodiversity because species restoration works in partnership with habitat restoration.
Helmut Magdefrau put forward their proposal to re-introduce choughs to Slovenia.
There was far too much to cover in one post. I will end with a photo gallery of chough sightings in Segovia and a couple of videos. All of which may help you plan your 2020 holidays!
La Palma island wildlife recovery centre: choughs often end up at the centre after collisions with power lines or collisions with cats mouths.
A blog post about cute pigs?! Nah. I’m just throwing you off the scent. Click bait. It is the monthly chough report of course with everything that happened in September.
Scoping out the racecourse
The chough flock spent at lot of time in September foraging around Les Landes Racecourse. There appeared to be plenty of insects available in the soil. Leatherjackets (cranefly larvae) from the looks of things although viewing through a scope a some distance adds uncertainty.
We still have a fair few turn up at the supplemental feed. The noticeable difference is that they are taking less food. Instead of finding empty food dishes within an hour of food being put out we find leftover pellet. Presumably because they have eaten so well out and about in the mornings.
Our rodent-proof food stands mean we can leave the leftovers for the choughs to snack on later. Hunger should not be a problem for Jersey’s choughs this month!
Class of 2019 suffer another setback
Another dead juvenile has been found out on the north coast. The body was found by a dog walker near Devil’s Hole. The lady regularly visits Sorel and knew when we would be feeding so kindly handed over the remains. We identified the bird as PP042 who fledged this year in the quarry. Not a huge surprise as they were on the missing birds list.
The surprise was the condition of the bird…headless and, on X-ray, very broken. You can see shattered bone in the left humerus (circled red in the image below). Our vet was a bit baffled at the post-mortem. The injuries sustained are something he is more familiar with seeing from a bird that had been hit by a car. Plus we don’t know if all this happened after the bird died or before.
We do know this means there are only 11 juveniles remaining. Three of those have not been seen in a long time. If they are still unaccounted for in October we will have to assume the worse.
PP035 is one juvenile very much alive and kicking. She was caught up mid-September because one of her plastic rings was unraveling. Not an easy thing to do for a bird to do. It would have required force. The ring was replaced and this time a lot of glue was used to seal the overlapping edges. She looked in good health and was released straight away.
The flock of sheep at Sorel were moved off site this month as part of their management plan.
There was, however, one little sheep who avoided the round-up. We found her merrily grazing away at the aviary. She had pushed through the fencing and entered the hedgerow bank rather cunningly hiding in the hedgerow when the shepherd was around and reappearing at the chough feed.
With a bit a team work and a lot of patience she was eventually moved out (it gave our push-mower a bit of a break!).
After seven years of working out at Sorel it felt quite eerie to visit and have no sheep and no choughs*. You can still find the sheep in various locations around Jersey doing their bit for conservation grazing. Maybe it could become the next rewilding game #whereswoolly?
*don’t worry we haven’t removed the birds, they do that themselves by flying off during the day.
Flocking season in the Zoo
At this time of year, with breeding over, we normally move all the Zoo choughs back into one aviary. This mimics the flocking behaviour you see in choughs over winter. However, this year was a bit different.
This is the first year we have had only one breeding pair at Jersey Zoo. It is also the first year we haven’t released parent-reared chicks. So that means trying to mix a family of four with the only other chough we have – Gianna.
Normally the other choughs ignore Gianna, but with one family and an uninvited guest in their territory things are a little different. We have made three attempts to mix Gianna with the group this month. The first time we assumed tensions were high because the male in the family had only just been moved back. He had been housed separately for the past two months due to bad behaviour. We gave him some more time to settle in and calm down before the next attempt. No change. We waited again. Surely the hormones had settled? Nope.
As soon as I leave the aviary the pair fly over and shout loudly at Gianna. If I then walk away from Gianna, they dive-bomb her and it gets physical. Thankfully, Gianna is thick skinned and once I’m back inside with her she returns to preening and picking out insects.
Sadly for Gianna I can’t live in the aviary and be 24-hr bodyguard (although the rent would be free). She has been moved back to her off-show aviary and might have to stay in there over winter.
New placement student
If Gianna does have to stay off-show she will receive lots of attention because….fanfare please…we have a student placement again! After more than a year with a vacant position, Flavio has joined the project.
He is with us until March and has already got stuck in to the task at hand. As evident in the video below. Faceal sampling for health checks, camera trap reviews for roost ID, and dealing with a dead chough all in Week 1.
Flavio has previously worked on a beetle conservation project in the UK so we are hoping to put his survey skills to use in Jersey. His mode of transport is a bicycle so be sure to give him a wide berth if you are overtaking – he has an expensive scope in his bag. I wouldn’t want it damaged!
The annual Inter-Islands Environmental Meeting was held in Alderney this year hosted by the Alderney Wildlife Trust. With the theme of Wilder Islands, delegates attended a two day symposium highlighting work carried out across the Channel Islands, Isle of Man and islands of the British Overseas Territories. Birds On The Edge was represented by myself and Cristina Sellares with Glyn Young joining on the challenging third day.
The third day was a mixture of talks and working groups tackling the challenges islanders face with biodiversity and climate change. Tony Juniper gave the introductory keynote speech.
We were also treated to an evening lecture from Dr George McGavin the esteemed entomologist and patron of the Alderney Wildlife Trust.
A separate blog will be posted going into more detail. The highlights for this report include the mention we got in Jamie Marsh’s talk on the white-tailed sea eagle reintroduction in the Isle of Wight. Guess where we might be taking choughs next? And our first possible sighting of a Jersey chough visiting Sark! Suffice to say our holidays work plans for 2020 are quickly filling up.
Building on the success of the Jersey choughs, can reintroduced choughs help restore Kent’s chalk grasslands? Could we eventually join the Cornish population and Kentish population to bring back this charismatic bird to England’s entire south coast as in days gone by? Ok, that last bit is jumping the gun. Although it is early days, the KCP are certainly working hard to make sure the first aim is achievable.
You can click the link here to read about Kent Wildlife Trust’s vision for a Wilder Kent.