Category Archives: Top News

Migratory birds under threat

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red-knot-photo-by-romano-da-costaFrom Science

A new paper in Science by Franz Bairlein highlights how habitat degradation and loss, illegal killings, and climate change threaten European migratory bird populations.

The populations of migratory bird species that breed in Europe and overwinter in sub-Saharan Africa are declining considerably faster than those of nonmigratory resident species or of migratory species that overwinter in Europe. Likely factors are habitat changes due to changes in land use, illegal killing and taking along the northern African coasts, and climate-induced changes in timing of migration and breeding. However, not only European trans-Saharan migrants are declining fast. This holds also for North American long-distance migrants wintering in Central and South America. To halt these declines, preservation of remaining habitats and restoration of habitats both at breeding and no-breeding grounds is essential, as well as stopping illegal killing and taking of birds along their migration routes.

Illegal killing and taking

Every year, between 11 million and 36 million birds are killed or taken illegally in the Mediterranean region. The areas of greatest concern are in the eastern and central Mediterranean, with more than five million birds taken in both Egypt and Italy and an estimated one million each in Cyprus and Lebanon. Common migratory species such as Eurasian chaffinch, blackcap, and song thrush are most affected, but many less common migratory species are also taken in substantial numbers, including species of global conservation concern such as red kite and Eurasian curlew. On average, the annual illegal killings and takings of threatened or near-threatened migratory bird species amount to 1-3.5% of their populations – percentages that are very likely to have considerable impacts on the fate of these species. Illegal trapping can cause a collapse in population numbers within a short period of time. For example, the yellow-breasted bunting was abundant in its Eurasian breeding range until illegal takings in China caused an 84% population decline between 1980 and 2013.

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Habitat degradation and loss

Many European migratory birds that overwinter in sub-Saharan Africa do not travel across those areas of the eastern Mediterranean most affected by illegal killings. Rather, they use a flyway across the western Mediterranean where illegal taking is much less intense. Other factors must play a role in their decline. A large number of European migratory species overwinter in the dry savannas of sub-Saharan Africa. Annual survival of many of these species correlates with rainfall in the Sahel zone. However, despite an increase in rainfall in the Sahel in recent decades, bird populations have continued to decline. Thus, factors other than rainfall must contribute to the population declines. Land-use and landcover changes are the most important. Between 1975 and 2000, agriculture increased by 57% in sub-Saharan Africa at the expense of natural vegetation, with nearly five million hectares of forest and non-forest vegetation lost per year. Most affected are the Sahel and Guinea Savanna zones where the majority of the Eurasian migratory species overwinter. An analysis of breeding-bird survey trends of 26 long-distance migratory species in the United Kingdom shows that wintering habitat is the most important determinant of population trends, with specialist species that occupy either open or woodland habitats in Africa showing declines.

Climate change 

Climate change is another major driver for biodiversity changes, including responses of bird populations. Many migratory species, including those that overwinter in sub-Saharan Africa, now arrive earlier at their spring breeding grounds. However, different organisms do not respond to climate change at the same pace, which has led to an ecological mismatch between some consumers and their prey. Dutch pied flycatchers, which overwinter in sub-Saharan Africa, do not arrive earlier at breeding grounds, but the populations of their insect food peak earlier as a result of warmer spring temperatures.

This mismatch between breeding and food availability has caused a decline of up to 90% in Dutch pied flycatcher population sizes. Climate change–induced changes in migratory bird populations are  evident in other species too, but their relative contribution to population changes in long-distance migrants wintering requires further clarification.

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A global issue

In North America, the Breeding Bird Survey shows that half of the migratory bird species are declining; declines in long-distance Neotropical migrants are more pronounced than those of birds that migrate short distances. As for the European–African migrants, climate mismatch is a factor, but the long-distance migrants are particularly sensitive to habitat changes. Similar patterns might be expected for migratory birds in East Asia, but large-scale and long-term breeding bird population surveys, population trends, and nonbreeding habitat assessments are largely missing for that region.

Outlook

Any attempt to understand and ameliorate migratory bird losses must consider threats far away from their breeding sites. These threats could include killing and taking, human disturbance at staging sites, pesticide exposure, or collisions with human obstacles such as wind turbines and traffic. The most important drivers of population declines in migratory bird species are likely to be land-use changes and connected habitat degradation and loss, but few studies have investigated the specific impacts of land-use and land-cover changes on migratory bird populations in detail. Such studies are urgently needed to disentangle the various factors acting on populations of migratory species.

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These studies must include carry-over effects, because conditions at nonbreeding grounds can affect reproductive success in the breeding season. Conversely, conditions at breeding grounds can affect nonbreeding fitness. In the red knot, climate-induced malnutrition at their Arctic breeding grounds resulted in shorter bills and reduced survival rates at their African wintering grounds. Future studies must also consider the role of stopover sites. Most long-distance migratory species rely on considerable fueling at such stopover sites before they embark on migratory flight, particularly if they need to cross oceans or deserts with no or limited feeding opportunities. The main fuel for migratory flights is fat. Consequently, migrants must accumulate enormous amounts of fat before migratory flights, some doubling their body mass within just a few weeks. To achieve that timed fueling, suitable habitats and food must be available at stopover sites. The effect of habitat loss and degradation at stopover sites on population trends in trans-Saharan migrants remains uninvestigated.

Consequently, future studies also need to clarify where species of conservation concern stop over and overwinter, and which migration routes they take. For example, British common cuckoos migrate along two routes to the same winter destination in sub-Saharan Africa. They face a much higher en route mortality when migrating along a western route than along an easterly route. Emerging technologies for tracking individual migratory birds throughout their annual cycle will reveal migratory routes and destinations in more detail than past bird marking, allowing more detailed and frequent assessment of the drivers of migratory species declines.

Existing data can, however, already be translated into immediate conservation actions to halt the decline of these migratory species. Wetlands can be protected from drainage; woody vegetation can be protected from grazing or even be replanted. Such efforts would not only support migratory birds but also the local biodiversity and livelihoods of local farmers and pastoralists. In addition, illegal taking and killing can be stopped. The required political instruments, such as the African–Eurasian Waterbird Agreement and the African–Eurasian Migratory Landbird Action Plan, are already in place. We just need to act, and we can if we wish.

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Birds On The Edge increases its presence

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birds-on-the-edge-flyer_page_1Earlier this year Birds On the Edge were invited to several very important public events in Jersey including the launch of the Jersey National Park. As a project of multiple partners it was rather unfortunate that we did not have any publicity material or displays of our own that we could use in our own right to help reach out to the very people who would most appreciate learning about the project. We sought, however, to change that and with the kind assistance of Christine Holmes and Rich Howell at Durrell have started to make our presence in Jersey better felt. We are indebted too to Romano da Costa and the BOTE team for allowing us to use these beautiful photographs.

First we produced three beautiful pop-up banners displaying the three key elements of the project: the farmland scheme, conservation grazing and the return of the chough. Each of these banners, standing at over six feet tall, will brighten up any function!

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To accompany the banners we created a full colour A5 flyer (top of page) that we can conveniently leave where people will pick them up and show them to their friends. In fact, please feel free to download one here, print as many as you like and spread the message!

Finally, and very importantly, as a thank you to our most important friends and partners – the farmers who are working hard with us to help the Island’s hard-pressed birds – we have produced a unique certificate of thanks. These beautiful documents convey our sincere appreciation to their hard work and they can be displayed on the wall as our permanent tribute for their efforts. They will also be useful during the farms’ environmental audits and on applications to funding bodies such as the Countryside Enhancement Scheme. These you can’t just download, you’ll have to join forces with us!

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Chough report: September 2016

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by Liz Corry

The six imported birds from Paradise Park, together with Durrell’s four foster chicks, begrudgingly completed their quarantine period this month. The foster chicks took an instant dislike to the latex gloves and quarantine footwear staff had to adorn which resulted in abject horror any time staff came near.

After a week of meet and greet between the half-inch mesh divide we mixed the Durrell four with the ‘newbies’. It was all very amicable and a lot of relief expressed amongst the newbies who took the opportunity to stretch their wings in the poly-tunnel. Having spent a week under cover they could also bathe in sunlight/shower in the rain/blow-dry in the crosswinds. Their frustration at being locked in the aviary was still apparent each time the free-living group returned to the aviary.

The quarantine group in the aviary paid a lot of attention to the free-living choughs. Often because they had no choice in the matter. Photo by Bea Detnon.

Weekly faecal screening showed that both groups had various levels of nematodes present in their faeces. Quarantine conditions were not going to eliminate Syngamus (gapeworm) from the group. They arrived with it and the outside group already had it prevalent in the population. However, to ensure that the group have the best chance of survival post-release we will worm the birds prior to release. In the meantime all staff could do was monitor the birds’ physical condition, try and minimise stress, and maintain hygiene standards.

A couple of this year’s wild-hatched chicks continued to have respiratory issues this month due to Syngamus. It is a lot harder now to trap the free-living group inside the aviary. The older birds (i.e. with more experience) have learnt to become more vigilant around staff if they see them near the release hatches. We did manage to lure in one of the wild chicks and treat with ivomec. He was quite thin and a lower weight than expected for a healthy bird his age. He was released straight away and has shown great improvement since. The other chick, from a different clutch, is still at large. She is sneezing and struggles with breathing if stressed. Easy to identify at the aviary at least. We will continue to monitor her and attempt to treat her when possible.

Wild chick (PP003) with parent back in July before she started showing signs of a Syngamus infection. Photo by Liz Corry.

A potential opportunity to worm the individuals with clinical signs of Syngamus arose when we caught the 2016 captive-bred chicks to attach radio-transmitters for post-release monitoring. The group we released in July were not fitted with transmitters because the manufacturers were still processing the order. This meant we now had all 10 locked inside to fit and the two parent-reared Durrell chicks to lure in from outside.

Sadly, the day the radio transmitters arrived in the post was the same day one of the parent-reared chicks went missing. Chick S  has not been seen since 18th September. He is the only chough to go missing in that time which adds to the suspicion that he has met an untimely end rather than flown away from Sorel. His disappearance is a significant loss to the group as a male and as Durrell’s first parent-reared chick.

One of Durrell’s parent-reared chicks is missing presumed dead after two months of being released into the wild. Photo by Bea Detnon.

We still had another eleven birds to catch up and attach transmitters to so work began with the inside group.

A radio-transmitter being fitted to the central tail feathers. The cardboard is used to keep the other feathers away from the glue. Photo by Liz Corry.

We teamed up with Durrell’s Vet Department to try and get as many birds as possible processed in one morning. With two people fitting the transmitters the entire group was done before lunchtime. Well we did start at 9am and had already given Chick X her gear a few days earlier.

With the bird in the hand it also gave the Vet an opportunity to check it over pre-release and for leg rings to be adjusted accordingly. The newbies had arrived with striped rings to distinguish between individuals. Some of the colours had proven difficult to read in the aviary. Once flying free it could only get worse so these were changed in-line with our ringing scheme.

Of course the one really obvious ring (green and white striped) turned out to be the only one that had broken and needed replacing. She now has the privilege of being the only Jersey chough with two red and white striped rings.

One of the Paradise Park choughs developed a swelling on one of their digits since moving into the release aviary. Photo by Liz Corry.

The Vet was happy with the condition of the birds taking into account the family of nematodes the choughs are harbouring at Sorel.

One individual presented with a swollen toe-pad evoking scary thoughts of bumblefoot.

The bird has not appeared to be in discomfort whilst being in the aviary or when we had her in the hand. We will continue to monitor this, but it terms of release she was given the all clear.

The last bird to be fitted with a transmitter was Chick T, the parent-reared Durrell chough living outside. With a bit of patience this was achieved a couple of days after the vet visit.

We had managed to trap two other birds in at the same time and had hoped to change a faded plastic ring on one of them. However, the weather was not in our favour so use of hand-nets in the wind and misty rain restricted us to our primary objective. Chick T was very compliant and was fitted with a transmitter in record time. He has now been officially named Trevor. A nod to Trevor Smith who works on Durrell’s Site Services team. He helped build the aviary and continues to help when major repair work is needed.

Chick T was the last of the 2016 captive-bred chicks to be fitted with a radio transmitter. Photo by Liz Corry.

The only concern we had with Trevor (the chough that is) was the presence of stress lines in his central tail feathers. These occur as the feather is growing at times when, for various reasons, the nutrients required for growth were not assimilated correctly. It is often associated with caged birds living in poor conditions, but can also be when healthy birds have a change in diet. For Trevor it might be related to the move from the aviary at Durrell to the aviary at Sorel where the diet is slightly different and the bird has access to a wider variety of insects.

Stress bars in the central tail feathers of a captive-bred chough. Photo by Liz Corry.

Trevor was released straight away to re-join the outside group who had been waiting around the aviary for the morning supplemental food. The free-living group have been getting on with life at Sorel relatively incident free. They appear to be finding more food in the wild, possibly related to the change in weather no longer desiccating insect larvae. There have been a few fights around the supplemental food bowls. With 25 birds and more to add soon, competition at feed times is to be expected. To address this we are looking to switch the ceramic dishes for specially designed chough troughs.

The checkout assistant may have questioned why I needed six end caps for one  length of guttering, but I left the DIY store content with my purchase and proceeded to make three new feeders. The choughs seem happy enough as now several birds can feed at the same time (or several feed whilst one walks down the middle).

Newly installed 'chough trough' at Sorel to help reduce competition. Photo by Liz Corry.

Newly installed ‘chough trough’ at Sorel to help reduce competition. Photo by Liz Corry.

The group has been observed using the area around the dirt-bike track a lot more for feeding as well as trips over to Devil’s Hole. They may well be going beyond that as we are not surveying them continuously. We had a report of a bird with an unusual call around the grounds of a house at the top of Waterwork’s Valley. The owner suspected it was a chough, but had no visual sighting. I also received a report of a single chough flying over a house at Victoria Village in the early morning.

Lee, Cauvette and Pyrrho have switched back to roosting at the aviary using the external roost boxes. Photo by Liz Corry.

Whilst each report had an element of doubt to it we can’t deny that the choughs will do things to surprise you and throw your own knowledge into doubt. Roost checks towards the end of the month revealed that three of the older birds have ditched their roost site in the quarry in favour of the external boxes at the aviary. Lee and Caûvette followed closely by Pyrrho return to the aviary at sunset.

There was a confused wild chick one evening who had become separated from the quarry group. After ‘discussions’ with the group locked inside he flew off towards the quarry calling all the way.

A wild chick separated from his roost group shortly before sunset looked for alternative accommodation at the aviary, but was turned away. Photo by Liz Corry.

The roost checks also revealed another interesting sight at Sorel….

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If you look hard enough at the photo of the three older choughs returning to the aviary (Lee, Caûvette and Pyrrho above) and, to be fair, use a certain amount of imagination, you will see a kestrel perched in the hawthorn tree. There are several kestrels around Sorel and an ongoing love/hate relationship with the choughs. The aviary provides a useful vantage point for hunting and attracts a lot of rodents (i.e. food). Of late the bond between chough and kestrel seems to have strengthened. This month they have been seen preening next to each other, sharing the same perch at the front of the aviary, and, more amusingly, flying together on the cliff face.

Lee and a few other choughs were observed hanging out with a kestrel on the cliffs flying in unison from rock to rock. Photo by Liz Corry.

We don’t know if it is the same kestrel each time, but there does appear to be one chough in particular who crops up in all the photos of these events; Lee. There is evidence of choughs associating with kestrels in other countries. Normally related to breeding territories and the benefit kestrels provide by deterring other bird of prey species which predate choughs. A lot more clinical and less anthropomorphic than our observations imply.

And finally….

The International Air show at the start of the month meant that once again the red-billed choughs ‘joined in’ with the Red Arrows display. Although this could only be appreciated from Sorel and photographic evidence is poor. A few of the planes used the north coast to turn around and re-group. Unlike last year the Red Arrows did not fly over the aviary much to the delight of the choughs locked inside. Those outside were making the most of the air currents along the cliff tops and put on an impressive display.

The Red Arrows in Jersey viewed from the release aviary at Sorel. Photo by Liz Corry.

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The Red-billed choughs flying in Jersey (Red Arrows just out of frame to the right). Photo by Liz Corry.

 

More than one in ten UK species threatened with extinction

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dartford-warblerIt’s not too late to save UK nature but we must act now – that is the conclusion from a coalition of more than 50 leading wildlife and research organisations behind the State of Nature 2016 report. Watch infographic here

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Following on from the groundbreaking State of Nature report in 2013, leading professionals from 53 wildlife organisations have pooled expertise and knowledge to present the clearest picture to date of the status of our native species across land and sea. The report reveals that over half (56%) of UK species studied have declined since 1970, while more than one in ten (1,199 species) of the nearly 8,000 species assessed in the UK are under threat of disappearing from our shores altogether.

There are many inspiring examples of conservation action that is helping to turn the tide. From pioneering science that has revealed for the first time the reasons why nature is changing in the UK, to conservation work – such as the reintroductions of the pine marten and large blue butterfly (and our very own red-billed chough) and the restoration of areas of our uplands, meadows and coastal habitats. But more is needed to put nature back where it belongs.

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lundy-cabbage-flea-beetleAs the UK Government and devolved administrations move forward in the light of the EU Referendum result, there is an opportunity to secure world leading protection for our species and restoration of our nature. Now is the time to make ambitious decisions and significant investment in nature to ensure year-on-year improvement to the health and protection of the UK’s nature and environment for future generations.

The State of Nature 2016 UK report will be launched by Sir David Attenborough and UK conservation and research organisations at the Royal Society in London this morning [Wednesday, September 14], while separate events will be held in Edinburgh, Cardiff and Belfast over the next week.

Sir David Attenborough said: “The natural world is in serious trouble and it needs our help as never before.

dormouse“The rallying call issued after the State of Nature report in 2013 has promoted exciting and innovative conservation projects. Landscapes are being restored, special places defended, struggling species being saved and brought back. But we need to build significantly on this progress if we are to provide a bright future for nature and for people.

“The future of nature is under threat and we must work together; Governments, conservationists, businesses and individuals, to help it. Millions of people in the UK care very passionately about nature and the environment and I believe that we can work together to turn around the fortunes of wildlife.”

In order to reduce the impact we are having on our wildlife, and to help struggling species, we needed to understand what’s causing these declines. Using evidence from the last 50 years, experts have identified that significant and ongoing changes in agricultural practices are having the single biggest impact on nature.

corn-buttercupThe widespread decline of nature in the UK remains a serious problem to this day. For the first time scientists have uncovered how wildlife has fared in recent years. The report reveals that since 2002 more than half (53%) of UK species studied have declined and there is little evidence to suggest that the rate of loss is slowing down.

Mark Eaton, lead author on the report, said: “Never before have we known this much about the state of UK nature and the threats it is facing. Since the 2013, the partnership and many landowners have used this knowledge to underpin some amazing scientific and conservation work. But more is needed to put nature back where it belongs – we must continue to work to help restore our land and sea for wildlife.

freshwater-pearl-mussel“There is a real opportunity for the UK Government and devolved administrations to build on these efforts and deliver the significant investment and ambitious action needed to bring nature back from the brink.

“Of course, this report wouldn’t have been possible without the army of dedicated volunteers who brave all conditions to survey the UK’s wildlife. Knowledge is the most essential tool that a conservationist can have, and without their efforts, our knowledge would be significantly poorer.”

The 2016 report includes a section on UK Crown Dependencies and highlights Birds On The Edge, Jersey Butterfly Monitoring Scheme, Les Minquiers, Guernsey’s Operation Skylark and Track a Gannet.

For a full copy of the State of Nature 2016 report and to find out how you can do your bit to save UK wildlife visit the website here 

Reports for different areas of the UK will be launched on the following days:

UK, England and Scotland reports – 14th Sept

Wales – 21st Sept

Northern Ireland – 26th Sept

All reports will sit on the Centre for Conservation pages on the RSPB website after their launch.

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The State of Nature 2016 UK partnership includes:

A Focus on Nature, A Rocha UK, Association of Local Environmental Records Centres, Amphibian & Reptile Conservation, Bat Conservation Trust, Biological Records Centre, Botanical Society of Britain & Ireland, British Bryological Society, British Dragonfly Society, British Lichen Society, British Pteridological Society, British Trust for Ornithology, Buglife, Bumblebee Conservation Trust, Butterfly Conservation, Centre for Ecology & Hydrology, Chartered Institute for Ecology and Environmental Management, Conchological Society of Great Britain and Ireland, Durrell Wildlife Conservation Trust, Earthwatch Europe, Freshwater Habitats Trusts, Friends of the Earth, Froglife, Fungus Conservation Trust, Guernsey Government, iSpotnature (The Open University), States of Jersey Department of the Environment, Mammal Society, Manx Birdlife, Marine Biological Association, Marine Conservation Society, MARINElife, Marine Ecosystem Research Programme, National Forum for Biological Recording, National Trust, National Biodiversity Network, Natural History Museum, Orca, People’s Trust for Endangered Species, Plantlife, PREDICTS, Rothamsted Research, RSPB, Sir Alister Hardy Foundation for Ocean Science, Shark Trust, Sheffield University, Vincent Wildlife Trust, Whale and Dolphin Conservation, The Wildlife Trusts, Woodland Trust, World Wildlife Fund, Wildfowl & Wetlands Trust, Zoological Society of London.

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Jersey trio make the top 10!

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by Liz Corry and Glyn Young

biaza-logoAs the State of Nature prepares to release its 2016 report that warns Britain’s wildlife is facing a “crisis” with more than 120 species at risk of extinction due to intensive farming, the British and Irish Association of Zoos and Aquariums (BIAZA) reveals the top ten native species being supported by its members. Three of those species are being supported in Jersey through the work of the Birds On The Edge team and it’s supporters.

BIAZA’s Director, Dr Kirsten Pullen, says, “Most people equate zoos and aquariums to holding and protecting animals that are exotic to the UK. Certainly, during their visits, the public expect to see a wonderful range of creatures from all around the world. What is not well-known is that not only do modern zoos do considerable amounts of conservation work globally, they also provide their skills and resources to help wildlife at home.”

Native species conservation efforts are often collaborative with BIAZA members setting up projects with other BIAZA zoos and aquariums as well as wildlife charities and NGOs. Modern zoological establishments provide husbandry expertise, support breeding programmes and help raise funds to ensure Britain’s wildlife has the best chance of survival in the face of increased pressures from climate change, agriculture and persecution.

The red-billed chough (Pyrrhocorax pyrrhocorax), number two in the top ten, is a perfect example. Today, much of Jersey’s coastal habitat, formerly an important resource for farming and grazing animals, is dominated by extensive swathes of bracken. With these changes the Island has seen the loss and decline of many birds such as the skylark, yellowhammer and stonechat.

Red-billed chough in Jersey. Photo by Liz Corry

The Birds On The Edge partnership between the Durrell Wildlife Conservation Trust, States of Jersey Department of Environment and the National Trust for Jersey has, through the active management of Jersey’s coastland, endeavoured to restore populations of birds and bring back the red-billed chough to the Island after an absence of 100 years.  Supported by Paradise Park in Cornwall, Durrell began to release captive-bred choughs in 2013. By 2015 the birds had successfully nested in the wild and bred again in 2016, so far resulting in a wild population of 30 individuals (July 2016).

Agile frog. Photo by Department of the EnvironmentAnother example, and number three on the list, is the agile frog (Rana dalmatina). Jersey is the only place in the British Isles where this frog species can be found. Its population has been declining in both range and numbers since the early 1900s and by the late 1980s there was a single fragile population in the south-west of the Island.

To prevent extinction, the Agile Frog Group, a collaboration of local environmental and conservation organisations including Durrell Wildlife Conservation Trust, launched a comprehensive Action Plan detailing threats and actions needed to save the frog. On going research since 2000, habitat restoration, and captive rearing at Durrell for release using collected spawn to tadpole and froglet stage (head-starting) have all helped to increase the species survival chances.  Today, nearly 50,000 froglets have been released since the project began in 1987.

Staff monitoring the agile frog release in Jersey. Photo by Gerardo Garcia

A few of the species on the list are absent from the Channel Islands such as the Eurasian beaver (Castor fiber) and common crane (Grus grus). In the case of the cirl bunting (Emberiza cirlus) considered locally extinct in Jersey after an eleven year absence, a few individuals returned naturally and have been nurtured and protected by the Birds On The Edge team ever since. Their numbers have grown steadily from the one pair which settled in 2011 to seventeen individuals including eight young from this year’s breeding season.

Cirl bunting at Grouville, Jersey. Photo by Mick Dryden.

 You can learn more about BIAZA’s top ten native species by going to http://www.biaza.org.uk/news-events/Biaza-news/

 

Chough release 2016

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by Liz Corry

The first release of this year’s captive bred choughs got underway on the 21st July. Six two-month old chicks from Durrell Wildlife Park were released from their aviary at Sorel to join the current flock of twenty four free-living choughs.

Adults and chicks enjoying the summer weather on the cliffs at Sorel. Photo by Liz Corry.

With more birds outside the aviary than inside, including four very loud wild chicks, the release cohort had more of a ‘hard’ release than the gradual introductions of 2014. The hatches were opened in the late afternoon much to the bemusement of the inhabitants. Once all thirty had mixed and mingled they were called down for food at the aviary, and then left to get on with it under the ever watchful supervision of the field staff.

Recently released chicks joined the free-living group for flying lessons. Photo by Liz Corry.

The release cohort is a mix of parent-reared and foster-reared birds which meant they had two different approaches to the ‘outside’ world. The parent-reared chicks had a tendency to follow the adults which meant they quickly learnt where the best foraging sites are, where to shelter from the rain, and how to react to potential threats most notably the peregrines. The foster four were not quite as willing or confident and tended to look to their foster parents for support.

A foster-reared chick doing its part for the Jersey Butterfly Monitoring Scheme. Photo by Liz Corry.

After the first evening flying at liberty around Sorel the six chicks returned to the aviary along with a few older birds and went to roost. The excitement of it all must have taken it out of them as the birds went in almost two hours before sunset and didn’t leave again until the morning.

Sunrise at Sorel: A panoramic view of the release aviary. Photo by Liz Corry.

Staff returned at sunrise to find one group of choughs breakfasting over on the other side of Mourier Valley. The begging calls of the wild chicks carried over the valley giving away their location.

The begging calls of the wild chicks carried over the valley giving away their location. Photo by Liz Corry.

Whilst another group were by the cliff path at Sorel. The foster chicks were at the aviary. On seeing their ‘parent’ (i.e. me) arrive over the brow of the hill the flew out to warmly greet and/or demand breakfast off her. This also involved landing on said parent’s head and backpack.  At first this behaviour was very concerning. Would they behave like this around other people? Are they going to be naive when faced with potential threats?

The foster reared chicks had to take things one step at a time when it came to the release. Photo by Liz Corry.

Over the next few days the chicks were put to the test by undercover bird keepers and unsuspecting public. They even had a few peregrine encounters. They passed every test and demonstrated how intelligent corvids really are. The foster four can identify their ‘parents’ from fifty metres away and will fly straight over to greet them. Or to be more exact if they think they can get an easy meal out of us. However, if we are with other people they won’t come near. As they grow in age and confidence and begin to find enough food to support themselves they should start to depend less on their foster parents.

Their young age is apparent not just by their behaviour, but by their physical appearance. The youngest chicks have a grey-yellow bill. Those a few weeks older have an orange colouration which should develop into the trademark red bill in another month.

A two-month old chough discovering the tasty morsels life in the wild has to offer. Photo by Liz Corry.

There are now thirty choughs flying free on the north coast of Jersey. It won’t be long before they start exploring and making appearances in other parts of the island.

Will the choughs decide to visit the newly restored Plemont headland this year? Photo by Liz Corry.

 

 

Chough report: July 2016

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by Liz Corry

“The Guide says there is an art to flying”, said Ford, “or rather a knack. The knack lies in learning how to throw yourself at the ground and miss”.
― Douglas Adams, Life, the Universe and Everything.

Wild and captive-bred chicks fledged and took flight this month. Photo by Liz Corry.

July was the month of learning and adventure for the captive-reared and wild-raised chough chicks at Sorel as they spread their wings and took the air for the first time. Fledging at the beginning of the month and, for the captive chicks, release into the wild before the close. And I’m happy to add that they landed on the ground safely.

Captive-reared chicks

The four foster chicks locked in the release aviary had already started stepping out of their nest-box and exploring their surroundings during feed times. In between they would hop back inside, preen and chat amongst themselves before falling asleep until the next feed. A simple life we all envy.

As they got older they spent more time exploring and by the 5th they had been given access to a section of the poly-tunnel to practise short flights and learn to fly to target areas for food. Weaning them off hand-feeding followed the same pattern as previous years although these four were less willing to find their own food than previous chicks.

Weighing the foster-reared chicks. Photo by Liz Corry.

The two parent-reared chicks at Durrell joined them on the 7th. They were caught up, given clearance by the vets, and transported to Sorel by keeper Jess Maxwell and student Bea. These chicks are two weeks older than the foster chicks and, therefore, a bit more independent by the time they arrived at the release aviary. That being said, at two months old they still have very strong associations with their parents and depend on them to bring most of their food.

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Parent-reared chicks from Durrell moved to the release aviary at the start of July. Photo by Liz Corry

Separation from their parents and the move to an unfamiliar environment  meant they were naturally stressed upon arrival. They appeared to adapt quite quickly though, finding food bowls in the aviary and some level of solace from the chough flock calling outside of the aviary.

After a day to adjust, they were mixed with the foster chicks and the group given access to the entire first half of the aviary. A week later they had the whole aviary to themselves and the free-living group were locked out. Observations before the move confirmed that no one was using the aviary as a roost site anymore so no one was being cheated out of a secure night’s sleep.

Chicks inside the aviary feed alongside those outside. Photo by Liz Corry.

Target training the captive chicks in preparation for their release was a challenge. The parent-reared chicks wanted to be with the free-living group. They could see and hear the wild chicks being fed by their parents just metres away and wanted in on the action. They also didn’t want to go down to the target areas on the floor as they had little trust in the people putting the food out. The latter was solved by setting up a target area on the shelf between the captive chicks and free-living group. This way the chicks could get to food straight away and start associating the sound of the whistle with the arrival of the adults and food.

The foster chicks on the other hand had no problem with going to the food. Just as long as the people putting out the food stayed with them. Their behaviour changed from curiosity over the ‘outsiders’ whilst in the nest-box to abhorrent fear of twenty-four noisy choughs descending en masse at feed time. Opting to hop in to a shelter-box and act all nonchalant or just go for a nap in between feeds.

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Adults arriving at the aviary in anticipation of an early feed. Photo by Liz Corry.

Trying to target train the chicks in between feeds, when the free-living group had left, was not successful either. The pressure on the parents to find food for the wild chicks meant they kept a keen eye on the aviary. Any hint that the keepers were going in or even near the aviary with insects for training and they would be over like a shot.

With time the foster chicks grew in confidence and started to eat alongside the adults and the parent-reared two settled down a bit around the keepers. Did they finally succeed in their target training? The ultimate test is always once they are outside of the aviary when they get released.

In the meantime…

Durrell’s breeding pairs return to their flock

Tristan and Iseult had a few days to adjust to the loss of their chicks followed by revelling in the peace and quiet of not having something insistently follow you around begging for food, before the other two pairs were moved back into the display aviary for the non-breeding season.

Gianna also moved back on show to join the flock, promptly ignore then, and turn her attention to her adorning fans (at least that’s how she views the public and keepers). This year she has the added enrichment of Durrell’s new keeper talks. Three times a week she has an audience to play to whilst we explain the important role the captive choughs have in the re-introduction project and Birds On The Edge.

Quarry capers

Viewing point in Ronez quarry used for observing chough nests. Photo by Liz Corry.

The wild chicks left their nests in the quarry sometime around the very end of June and first few days in July. As all choughs chicks do at that age they spent time exploring their nest sites, i.e. inside the quarry buildings, before making an appearance outside. The parents could be seen taking food back to their respective sites, but not always venturing inside. On one occasion Dingle or Red went to the staircase at the side of the building, perched at the doorway (opposite side to the nest), and started feeding something. Presumably her chick and not one of the quarrymen. We were able to record this activity because Ronez Quarry kindly gave staff access to the viewpoint. Our vantage points from Sorel or the Ronez loop road would not have had the same line of sight.

Once the chicks had ventured outside it was a bit easier to track their movements. They were the choughs that stayed on the buildings when every other chough flew away to the aviary for supplemental feeds. White and Mauve’s two chicks had a tendency to walk back into the building once their parents had left. Who can blame them with black-backed gulls nesting close by and the juvenile peregrines having introductory lessons on how to hunt in and around the quarry.

Two wild-hatched chicks making their first appearance in the quarry. Photo by Liz Corry.

Green and Black continued to return religiously to their nest site, often carrying food. The debate over whether or not they still had a chick was fuelled further when a fledgling was spotted on the roof of their building. Was this the fifth chick or was one of the other four making its way out of the quarry one building at a time?

The answer came when the chicks made their first flight out of the quarry. On the morning of the 4th four chicks were spotted at the bottom of Sorel Point with the other choughs. Lee, released last year, was observed pulling at the tail of one of the chicks. Not your typical welcome greeting. By the afternoon they had followed the flock to the aviary and were merrily feeding and begging and feeding and begging and feeding…

Dingle, a hand-reared bird, with one of his wild hatched chicks waiting for supplemental food. Photo by Liz Corry.

Mauve with one of her two wild-htached chicks at the release aviary. Photo by Liz Corry.

Anyone with experience of wild choughs will know how loud and incessant chick begging can be. And it lasts several weeks much to the dismay of the parents. Green and Black did not have a chick with them. Hopefully not having to participate in the cacophony of chick begging was some sort of consolation to them.

A wild chick being fed the supplemental diet by a parent outside the aviary. Photo by Liz Corry.

Veterinary intervention

Black was not in the best of health anyway. We had noticed for some time that she was returning from the quarry sneezing. Her symptoms started to worsen as fledging time approached. We intervened on the 6th after managing to get an individual faecal sample from her in the wild.

To catch her in order for the vet to administer drugs we tried trapping the group in the aviary at the feed. Normally this is an easy task, but the presence of the wild chicks meant that the chough families were on high alert and scarpered at the first sign of a staff member approaching the release hatches. The only two birds we could lock in before they had time to realise were Black (because she was ill) and Flieur.

This turned out to be useful as Flieur had lost her colour ring a couple of weeks prior so a replacement was fitted and she was released. Black was caught up, weighed, treated and released. Her breathing was very laboured and the worst we have seen to date. There was potentially a need to give a follow up wormer in two weeks times. Normally treated choughs stop sneezing within a day or so and don’t need the second injection. Black continued sounding rough for a week before clearing up. As always we observe daily and submit group faecal samples to the vets once a month to monitor the birds’ health.

Dusty, Egg, and Chickay

The nest site discovered in June potentially belonging to Dusty and one of his females failed to produce anything. Not too surprising as all three are quite young and it was their first attempt. Dusty and Egg continued taking food from the aviary to the quarry. Chickay remaining faithfully by their side feeding and preening Dusty when asked. As with Green and Black it would appear they were simply caching food for themselves away from the flock. Very sensible as competition grew over food bowls at the aviary in response to an increased demand for food.

Summer finally arrived…for a day

The 19th July saw temperatures in the aviary reach 34°C and the hottest July in Jersey. In fact the third hottest day since records began. Extra water trays were provided at the aviary. For the public the sight of sunbathing choughs might have appeared quite alarming since they often look like they have just been shot and fallen from the sky. They are just making sure every feather gets a piece of the UV action and any feather mites zapped out of existence.

A sun-bathing juvenile chough. Photo by Liz Corry.

Their main struggle with the weather was the fact that Sorel had not experienced much, if any, rain for a few weeks. With no shade cover or water the sun-baked ground had hardened to the point of cracks appearing. No chance of getting to any insects in the ground, assuming there were any. The sheep dung was also absent of insect larvae. Wild food resources for the choughs had become depleted and their dependency on the supplemental feeds increased. The effect it had on the flock added an extra challenge to the 2016 chick release.

The heat also appeared to have an effect on humans and their awareness of their surroundings. Scorch marks on the dry grass land at Sorel and Devil’s Hole show that people have had disposable barbecues and in one case a log fire on National Trust Land. The latter is illegal. There also seems to be an increase in the number of cigarette ends left around the site. With sun-parched grassland and heath these activities can be extremely dangerous. Exemplified by an incident at Grantez in which memorial bench was badly burnt when somebody left a used disposable BBQ under it.

Disposable barbeque damage to a memorial bench on National Trust land in July. Photo by Jon Parkes.

Preparations for release

As well as target training the captive chicks for their imminent release, staff worked on preparing the aviary. Simple tasks of oiling locks and hinges turned into DIY repairs to replace hinges and framework. A spot of up-cycling turned a pallet board and reclaimed wood from Durrell’s wood skip into steps and benches so keepers could securely reach the hatch locks. In the past we relied on conveniently placed logs and rocks. Not necessarily health and safety compliant, made worse by wear and tear over the years. The added bonus of the new additions was their unintentional enrichment benefits for the choughs.

The bracken started to fight back against the sheep this month. Photo by Liz Corry.

The biggest task was clearing the bracken from the embankment to allow the choughs to see from inside the aviary over to the grazed land. This helps with the release and provides an extra area for them to forage close to the aviary. This time of year the bracken reaches record heights in some places towering above both sheep and people. Removing the bracken by the aviary revealed a few desiccated toads and opened up areas for a slow worm and the occasional green lizard. It also meant the rats had fewer places to hide.

Bracken clearance alongside the aviary provided extra foraging ground for the choughs as well as a clear view. Photo by Liz Corry.

The aviary netting started to get to a lot of unwanted attention from rodents once the hatches were closed off to hold in the captive chicks. With no obvious way in and out to get to any spilt food left by the choughs the rodents took to chewing holes in the netting. The battle is ongoing with the rodents favourites to win.

Rodent activity in and around the aviary creating problems with the netting. Photo by Liz Corry.

Final preparations

Before take-off, the chicks need a clean bill of health. On the morning of the 19th chick V was missing from the melee that is breakfast time. A quick search of the aviary found her perched in one of the shelter boxes holding her head back and to the side. She wasn’t saying much and didn’t come for food straight away. With a bit of coaxing she came down and walked along the shelf to the food and the other chicks. She half halfheartedly begged and ate a mealworm then shuffled off into another shelter box.

Chick V was under the weather on the 19th, but perked up on hearing the threat of a vet visit. Photo by Liz Corry

Close, very close, observations of her throughout the morning showed no change and a tendency to hold her neck awkwardly. The Vet visited in the afternoon to examine her. She had perked up by that point (as animals always do when they know the Vet is on the way), yet still not 100%. With nothing obvious to diagnose a blood sample was taken and sent off to the lab. We had a two-day wait before hearing she had the all clear. By which time she was back to normal and understandably a little cautious around keepers.

Congratulations it’s a boy, and a girl, and another girl, and a boy….

The day after the vet visited we heard back for the diagnostics lab regarding the sex of the 2016 chicks. We now know that the foster four are all female and the parent-reared zoo chicks are both male.

In the wild we have a nice 50:50 split. We have a question mark over one of the samples so we cannot be 100% sure without taking another blood sample. Looking to tarsus (leg) length as an indicator it suggests the individual is female. If it turns out to be male then we have three males in total hatched in the wild this year.

Operation Chough

Paradise Park successfully raised ten chough chicks this year including two hand-reared. Once they have their sexing results they will work out which chicks can be sent over to Jersey to take part in the release. The plan is for the Durrell chicks to be released as early as possible to learn what life is like outside the aviary and acquire skills. When the Paradise Park choughs arrive we will call the Durrell chicks in to the aviary and lock the group in together whilst the UK birds fulfil their quarantine requirements.

After which point, the two groups will have socialised and formed relationships or at least connections. Once released, the Paradise Park chicks will hopefully follow the Durrell chicks and learn from them.

Paradise Park established Operation Chough in 1987. Our partnership since 2010 has now helped their objective to come to fruition. With the second release this year involving their chicks, Jersey’s free-living flock could reach a total of 36 individuals.

 

How many birds are there in the Channel Islands? – an update

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Kestrel and Elizabeth Castle. Photo by Romano da CostaHow many birds are there in the islands? That is bird species. Not individual birds as we can never really know that (well, except for the choughs). Each, since year since 2006 we have jointly published a list of the species seen on Jersey, Guernsey, Alderney, Sark and the sea area and smaller islands associated with each. The latest list, updated to the end of December 2015 is now available to download here and on our islands’ local bird sites.

Disappointingly there were no new species for the region recorded during 2015 but there were some minor changes to the individual Islands’ lists. Guernsey picked up its first glossy ibis (one at Vale Pond in October) and Alderney its first long-tailed skua (at sea in August). Alderney (on 8th November) and Jersey (on 22nd November) saw their first rose-breasted grosbeak – both records presumed to be the same bird (Guernsey had one of these North American vagrants in 1987 and Sark one in 1975).

Dartford warbler July 2006. Photo by Mick DrydenA remarkable 26 roseate terns were recorded in Jersey during the year and may possibly have bred. A tree sparrow put in a rare appearance in Guernsey – this bird has been recorded each autumn flying over Noirmont, Jersey, in recent years – and 22 bee-eaters were recorded in Jersey. Dartford warblers had mixed fortunes with two of these former breeding birds recorded in Guernsey but none were in Sark where the species had been breeding since 2002.

Other notable birds included Canada geese in Jersey and Guernsey, Guernsey’s sixth record of the rapidly increasing great egret, Alderney’s third black stork and second great bustard (like the 2014 bird the latter came from the UK reintroduction project), Little (house) swift. Photo by Mick DrydenGuernsey’s second and the islands’ third little (or house) swift, Jersey’s fourth red-footed falcon, Alderney’s third rose-coloured starling and Guernsey’s fifth black-headed bunting (all Channel Island records of this bird are from Guernsey).

And, of course, the first red-billed chough (Dusty) to hatch in the wild in Jersey for around 100 years put in an appearance in June.

Jersey’s bird total has risen to 330 and Alderney’s to 287. Guernsey’s, however, has actually dropped to 323 as they have removed three species of wildfowl from their list as their provenance is unknown (i.e. they could have hopped over someone’s fence). These three, barnacle goose, mandarin and red-crested pochard are renown escapees but two (the goose and the pochard) have been recorded reliably in Jersey. Mandarin have established, from formerly captive birds, a small but seemingly self-supporting population in Jersey as they have in the UK. Interestingly, a flock of, at least formerly, captive barnacle geese commute regularly between Guernsey and Jersey.

How will 2016 change things? One thing is certain, since the launch of the Alderney Bird Observatory, we could have a much clearer idea of bird migration through our islands.

Barnacle geese fly in. July 2016. Photo by Mick Dryden

Download the Working list of Channel Islands birds to December 2015 here 

 

Jersey cirl buntings – are they nearly back yet?

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Cirl in Grouville, Jersey. Photo by Mick Dryden 28-4-2016 (5)

The decline and subsequent disappearance of the cirl bunting in Jersey was one of the catalysts behind the formation of Birds On The Edge. With 17 singing males recorded across the Island in 1997 (by Mick Dryden and Nick Milton) the species appeared extinct locally when the ‘last’ one was seen at Beauport in 2004. Cirl buntings had undergone a longer decline in the UK but conservation efforts, led by the RSPB, were initiated in the late 1990s. Jersey watched the UK work closely, and liaised with the RSPB to see whether there were areas of the work that we could replicate over here (Note BOTE’s Cris Sellarés was part of the UK bunting team – report here).

Cirl in Grouville, Jersey. Photo by Mick Dryden 7-7-2016 (2)We discussed in Jersey the bunting’s decline with the RSPB’s Cath Jeffs, RSPB Cirl Bunting Project Manager, who visited the Island to look at the bird’s former sites and assess possible measures that could be addressed to restore the bunting to its Channel Islands’ home. In June 2011 our hopes (fanciful dreams?) of the species’ return were realised when a male cirl was found at Les Landes Racecourse (by Mick again). Later that month a pair were found in Grouville on one of the BOTE bird monitoring transects (see the BOTE report here). Breeding was confirmed in 2012 when Mick found a chick with the adult pair.

We held a meeting to discuss how best to manage the habitat of the one bunting pair in October 2012 (report here) and were grateful to the Société Jersiaise Ornithology Section, National Trust for Jersey, Durrell, Grouville Tenants, Royal Jersey Golf Club in Grouville, Department of the Environment and Cath Jeffs for their support. Areas discussed included sensitive management of the existing breeding habitat of the cirl buntings and the monitoring and supplementary feeding of the birds.

Cirl in Grouville, Jersey. Photo by Mick Dryden 28-4-2016 (4)

Food has been provided for the buntings, notably by the fantastic Richard Perchard, without whose tireless effort our story might have been different, to ensure that any food-finding problems the buntings might encounter in the remaining Jersey habitat throughout the year were cancelled out. The bunting’s story was updated in 2013 and 2014 and, despite setbacks (see report of a fire here) they appeared settled.

This year, 2016, was chosen for a British Isles-wide survey (well, Devon, Cornwall and Jersey in the most part) to see just how the cirl bunting population was doing with all the effort being put in. And so, we waited to discover what Jersey’s population had done in 2016. Mick Dryden once again led surveys of the site in south-east Jersey and with a team of volunteers counted each and every bird in April, at the start of the breeding season, and again in July.

So, how are we (well, the buntings) doing? Mick reported that there were six birds in April, at four territories – this meant that potentially there were also unseen (nesting?) birds. And, in July, after they’ve had a chance to breed? Mick and the team reported 17 birds including eight young from three pairs!

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Puffin and shearwater numbers surge on Lundy after rat eradication

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Atlantic puffin (3). Photo by Mick DrydenFrom Rare Bird Alert

More than 300 individual puffins have been counted on Lundy Island this year, compared to just five birds ten years ago, thanks to a seabird recovery project.

Rats, which feast on the eggs and chicks of burrow-nesting birds such as puffin, were eradicated from the island between 2002 and 2004 as part of the Lundy Seabird Recovery Project, with the island being formally declared rat-free in 2006. See the BOTE report on the project in the Isles of Scilly and Lundy here

Other seabirds have also thrived, including Manx shearwater, with the most recent figures recording some 3,400 breeding pairs, from a low of only 300 pairs when the recovery project was planned and conducted.

Helen Booker, RSPB senior conservation officer, said:  “We expected Manx shearwater would benefit from rat eradication, and we have certainly seen that, but we were much less optimistic about puffin. Ten years ago its population had reached such a low level we worried whether it would survive, to see that puffin is now doing so well really is exciting.”

Becky Macdonald, the Landmark Trust’s warden on Lundy, said:  “The increase in Lundy’s seabird colonies, particularly the enigmatic puffin and elegant Manx shearwater, illustrates the importance of seabird recovery projects and the need to protect our seabird populations from controllable threats, such as predation by non-native mammals.”

Atlantic puffin (2). Photo by Mick DrydenThe Lundy Seabird Recovery Project was mainly intended to boost the population of Manx shearwater, which were a higher conservation priority at the beginning of the century. But the puffin’s problems have multiplied since: the bird is struggling in northern Scotland, Orkney, Shetland, the Faroe Islands, Norway and Iceland, following a crash in the number of sandeels, the puffin’s preferred diet, probably triggered by warming sea temperatures.

There has been no breeding at all in some of the northern colonies in ten years. Whereas birds in places such as Lundy, but also in South Wales, Ireland, and elsewhere around the Irish Sea, have been able to exploit alternative food sources, such as pilchards and anchovies, numbers of which appear to be increasing in the southern parts of the puffin’s breeding range.

Dr Euan Dunn, RSPB seabird specialist, said: “puffins are facing serious threats, so it’s really important to have healthy colonies in places like Lundy in order for the bird to retain a resilient population, especially to combat the effects of climate change.

“In numerical terms, Lundy’s population is still modest but in terms of establishing a UK-wide halo of viable puffin breeding stations I attach real significance to this recovery.”

Manx shearwater. Photo by Mick Dryden (2)The Lundy Seabird Recovery Project was a partnership between the RSPB, the Landmark Trust, Natural England, and the National Trust.

John Holmes, Natural England’s area manager, said:  “This is fantastic news and a remarkable result over a relatively short time. It just shows what a concerted effort by a committed group of partners can achieve.”

Rob Joules, the National Trust’s general manager for Lundy, said:  “It’s great to reach the ten-year milestone of Lundy being rat-free and to see its wildlife thriving in direct response. This was an incredibly important and worthwhile project to be involved with and it’s great to know the lessons learned are being implemented on other offshore islands around the UK.”

Storm-petrel, which nests in small burrows or crevices among rocks, and whose breeding sites are also often plagued by rat predation, was recorded breeding on the island for the first time in 2014. Because the bird nests in inaccessible places precise figures are difficult to obtain, but up to 100 are now thought to be present.

Atlantic puffin. Photo by Mick Dryden