The Calf of Man

The Calf of Man is a 250ha island lying only 500m to the south of the Isle of Man (read more here). It was once home to thousands of nesting Manx shearwaters, the burrowing seabirds that got their common name from these islands. However, brown rats (also known locally as ‘longtails’) landed on the island from a shipwreck in the late 1700s. The rats proceeded to wipe out the huge Manx shearwater colony, and since then only a few of these iconic birds have managed to breed on the Calf. During the autumn and winter of 2012-2013, a team from Manx National Heritage, the Manx Wildlife Trust, Manx Birdlife, the Isle of Man Department of Environment, Food and Agriculture, the Animal Health and Veterinary Laboratories Agency (AHVLA) and the Royal Society for the Protection of Birds worked to eliminate rats from the Calf of Man and make the island safer for all nesting seabirds and encourage the resurgence of the shearwater colony.

The small island is dominated by maritime heath, bracken/bluebell and grassland both semi-improved and maritime. Small patches of wet flushes, marshy grassland and rock outcrops all go to form a diverse landscape. Over 340 species of plant have been recorded. Red-billed choughs breed on the sea cliffs and Atlantic puffin once bred on the island but their decline and eventual disappearance are likely to be a result of the rats’ arrival.

The rats and the seabirds

Rats will eat the eggs and chicks of almost all nesting seabirds that they can get to and have been known to kill the adult birds too. There is evidence from all over the world that where rats are present on seabird islands, the seabirds suffer large losses from rat predation. However, not all is lost. There are increasing numbers of programmes to remove rats from seabird islands and there is dramatic evidence of their success even in local waters. Following a rat eradication programme on Lundy Island in the Bristol Channel between 2002 and 2004, monitoring of burrows in 2008 showed an estimated 1,081 pairs of Manx shearwater, an increase of 250% in numbers since 2001.

The Calf project team expects that seabird breeding productivity on the island will start to recover immediately following the eradication. An anti-coagulant bait block, a “first generation anti-coagulant” called Coumatetralyl, was used to kill the rats. This acts by blocking the synthesis of vitamin K and causing internal haemorrhage. The bait was administered in boxes or pipe tunnels to which rats could gain access. Simple blocking devices were needed to discourage entry by young rabbits and birds such as crows.

Poisoned rats typically die below ground in burrows and are unlikely to be eaten by predators such as ravens and gulls. Although secondary poisoning of non-target mammals or birds could not be ruled out, the use of Coumatetralyl was particularly appropriate for environmentally sensitive applications due to its low persistence and low toxicity to birds. A risk assessment was completed for key non-target species on the island particularly for the wood mouse which, although not recorded on the Calf for some time, may still survive. Live traps were maintained in the hope of catching mice for transferral to a safe place and return following the eradication operation. However, no wood mice were found, though the project team suspect that some have survived the rodenticide deployment. Pigmy shrews, an insectivore unlikely to be attracted to the poison bait and Loaghtan sheep were not affected by the poison through careful management of the bait. To the surprise of the team, some young rabbits seemed to be attracted to the chocolate wax blocks used as non-toxic monitoring bait after the eradication phase.

Although also an invasive mammal, rabbits are desirable on the Calf as they provide burrows which shearwaters and (hopefully) puffins can use. Together with Loaghtan sheep, they help keep the grass short which benefits other wildlife such as choughs and low-growing herbaceous plants.

How do you know if eradication has worked?

Following the main eradication phase, chocolate wax-blocks were placed around the Calf, particularly to the coastal fringes where any re-infestation might occur.  It will be necessary to monitor these points into the foreseeable future and certainly for the first two years after eradication in case there are any remaining rats not dealt with during the intensive baiting phase.

Is there a risk of re-invasion?

The project team cannot be sure that rats will not re-colonise the Calf of Man, but they can minimise the risk of a new invasion. Quarantine for all boats and ships that plan to land on the island will need to be enforced and it is hoped that all boat owners who like to frequent the Calf will co-operate fully with all requirements.

Unauthorised landings and shipwrecks will remain a threat but much less so than in the past because of more hygienic conditions on board and tighter controls on landing.

Since rats are able to swim, it is conceivable that they could reach the Calf across the Sound via Kitterland but it is anticipated that the generally strong tidal conditions may reduce this risk.  Monitoring will continue on Kitterland periodically to detect any build up of rat numbers and allow a fast response to eliminate them.

At the time of writing the project team remain cautiously optimistic, despite one suspicious incidence of rat sign which has been dealt with by means of localised intensive baiting.

Do similar situations exist in the Channel Islands?

Yes. Rats may be the main reason that puffins are so rare in Jersey and shearwaters barely survive in Sark. It is probably hundreds of years since a Jersey puffin nested down a proper earth burrow, those that have nested have done so in rock crevices and fissures that the rats can’t reach. Manx shearwaters and storm petrels were probably also widespread here once. Today the Islands’ only real hope for burrowing seabirds is Burhou. This island is rat-free but if any rats ever reached it we could lose all these
puffins. There are plenty of rats on our north coast and while it would be much harder to remove them from areas like Tête des Plémont it is not necessarily impossible. But it would take hard work and a long term commitment and, who knows, maybe Jersey’s puffins could once again be safe and shearwaters once again nest here.

Sincere thanks to Kate Hawkins, Curator: Natural History, Manx National Heritage for helping compile this report.

This month saw the further extension of our Farmland Bird Monitoring programme. Four new sites, relatively close to each other in St Martin, were brought in to the overall scheme. Birds recorded at each of the sites will be entered into the project database but will also be used for farmland management trials aimed for 2014 as part of a joint project by the Department of the Environment and Game & Wildlife Conservation Trust. These four farmland sites join two woodland sites (at Rozel Manor and Le Saie) in the trial.

The four new sites are at Ville es Nouaux/La Fosse (a single 1,037m transect), Rozel Mill (1,203m transect), Gibraltar/St Catherine’s (1,027m transect) and at La Coupe/Fliquet (1,170m transect).

The new sites bring the total number of monitored sites in this programme to 20 with two of those having two separate transects (22 transects in total). We count all the birds along 25,439 metres of transect every fortnight. That’s 15.8 miles birdwatching at least twice a month in all weathers!

During this month we have also recorded two new bird species on the transects. On 2^nd June, Harriet Clark recorded a very rare common quail on the new transect at Gibraltar/St Catherine’s. Quail are a migrant species breeding in Europe and wintering in Africa. Sadly, quail are becoming rarer through hunting and loss of suitable breeding and wintering habitat. We record single birds in most years in the Channel Islands but they are still a very good sighting. Harriet’s quail became the 159^th bird species recorded during the monitoring project.

The 159^th species was very quickly followed by the 160^th. We finally found an oystercatcher! Oystercatchers can be heard at some sites during every single visit, but, as they are typically either at the base of the cliffs or flying at sea (they are very, very noisy and their voices carry) but, as they aren’t really using the site we are monitoring, they haven’t been counted. However, on 11^th June, Tim Liddiard found an oystercatcher actually walking on the path we use as the Les Blanche Banques transect. This bird was presumably one of the pair nesting at the nearby sandpits.

From Alderney Wildlife Trust

A team from The University of Liverpool and the Alderney Wildlife Trust made the first of what will be many visits to Alderney’s seabird colonies on 20^th May. The team started the process on Burhou capturing shags, a declining seabird of which Alderney has a significant number. Once caught, each bird will be fitted with a small waterproof GPS data-logger aimed to uncover much about the birds’ lifecycle, their feeding and foraging habits and the potential impacts that marine developments, such as renewable energy installations, may have. It may also throw light onto issues such as fishing practice and marine pollution incidents within the English Channel.

After some intense sessions trying to catch and tag the somewhat elusive shags, the team will move on to tagging the much more accessible but aggressive northern gannets. This will be done with the help of the Channel Island Ringers and other organisations. By monitoring two species at once, one which tends to feed close to its nesting site (the shag) and the other which can travel well over 200km on a single foraging trip (the gannet), it is possible to get a much broader picture of how our breeding birds use Channel Island, French and UK waters to survive. Both bird species fly between roosting and feeding sites and capture their prey by diving into the water column. This means that they could encounter wind turbines while flying above the water and tidal turbines while foraging below.

Each GPS tag will stay on the birds for approximately five (shags) or 10 (gannets) days before the team returns to retrieve them. These tags will not cause the birds any discomfort and will fall off by themselves after a few weeks if not retrieved as planned. The information the tags contain can be downloaded and, it is hoped, contribute to a growing body of information which is forming the basis of a PhD being undertaken by Victoria Warwick-Evans.

A trial project undertaken in 2011 saw 23 GPS data loggers attached to northern gannets breeding on Les Étacs, Alderney. Within six days, 17 of the loggers had been retrieved, revealing the locations of 34 foraging trips. Interestingly individuals seemed to specialise their feeding in different areas with some flying to the south coast of England, some southwards to Jersey and others heading east towards Le Havre on the French coast. Amazingly on one occasion a gannet made a 340km round trip, and several made two trips to the South Coast of England within 72 hours. Preliminary analysis suggests that Alderney’s gannets make longer foraging trips than those breeding at some UK colonies but are comparable to the distances travelled by their closest neighbours breeding on Les Sept Îles, Brittany. Evidence also suggests that there is little overlap between the foraging sites of the gannets from Brittany and those from Alderney: the French gannets tend to stick to the western English Channel whereas Alderney’s appear to feed more towards the eastern end of the Channel.

Victoria from the University of Liverpool says that she is “thrilled to be part of a team studying the intricate foraging behaviours of these impressive seabirds, and excited to have the opportunity to use this data in the development of models in order to predict any effects that offshore developments may have on these seabird populations.”

Tim Morley, Ecologist from the Alderney Wildlife Trust says that “the chance to better understand the life of our seabirds during the breeding season is something that excites us at the AWT, and we are privileged to be working with the University of Liverpool team in this venture. The results will be a key focus of our future conservation efforts amidst growing concern over marine pollutants, fishing practises and the intensity of traffic through the British Channel”.

The project is being run by The University of Liverpool, funded by the Natural Environment Research Council (NERC) and the Alderney Commission for Renewable Energy (ACRE), with the support of the Alderney Wildlife Trust.

From Alderney Wildlife Trust

On Monday the Alderney Wildlife Trust recovered a dead guillemot from Braye Harbour in Alderney. This was the first bird recorded in the Channel Islands as being killed, it is believed, by Polyisobutylene (PIB). The discovery of this bird took place at almost exactly the same time as it was announced that over 1,000 seabirds had been found washed up dead on the south-west coast of England during the previous seven days, killed by PIB. Equally alarming was the news that 19 species had now been affected, with the hundreds of birds found dead and dying along the coast including large numbers of guillemots, and even puffins. Gannets, which were also found amongst the dead, may well include birds which were breeding at the only Channel Gannetries of Les Etacs and Ortac, just off Alderney’s coastline.

An earlier incident in February of this year and involving PIB killed hundreds more birds, raising the question as to what the future is for seabirds in the English Channel if these incidents continue to grow in regularity and scale.

PIB is used as an additive to oils and is currently listed under the MARPOL Convention as being legal to discharge from ships at sea, under certain conditions. Investigations into the February incident were abandoned by the Marine Coastguard Agency (MCA) as they ‘concluded that it is highly unlikely we will be able to link the pollution to any specific vessel.”

Roland Gauvain Manager of the Alderney Wildlife Trust commented:

‘We are extremely concerned that, though we haven’t seen large numbers of dead and dying wildlife on Channel Island beaches, this is probably down to blind luck and strong southerly winds. If the wind direction had swung to the north it may well have been our islands which would have experienced the horrendous site of hundreds of dead seabirds on our beaches. 

It’s even more important to recognise that we don’t know as yet how much damage has been done by these discharges! With as many as 2,000 birds having been found dead or dying in the UK in the last few months alone, we have to ask ourselves; how many of these birds would have bred in the Channel Islands? The answer is we simply don’t know and we will not be able to tell until much later in the season. Yet, with the guillemot colony of the Guernsey Humps yet to return this year, it may well already be too late for some of our Channel Islands most special wildlife..

The Alderney Wildlife Trust is calling on the Channel Island Governments to back the growing demand of key UK NGO’s, including The Wildlife Trusts Partnership, to have the International Maritime Organisation (IMO) reclassified PIB to prohibit its dumping at sea.

Joan Edwards, Head of Living Seas for The Wildlife Trusts, said:

‘Dead and dying seabirds may be the most visible victims of our mismanagement. Impacts on other parts of marine life support systems may be just as widespread, and more serious. Firm controls must be implemented to minimise future disasters such as this and which allow deliberate offenders to be held to account.’

Further the Alderney Wildlife Trust will be calling for a joint seabird monitoring strategy for the Channel Islands.  Mr Gauvain added:

‘Our marine wildlife is one of the strongest parts of the Channel Island identity.  It’s a crucial indicator of the health of our environment and vital for our tourism industry. This incident highlights the need for joint working between the islands to protect our crucial natural resources and prepare a joint response to man-made disasters such as this.

From BTO

Recent research on declines in Afro-Palaearctic migrant birds has primarily focused on conditions in these species’ wintering grounds. However, population changes could also be influenced by factors during breeding and migration, as a new study shows. Read the abstract here

The study’s authors analysed data from the BTO’s Breeding Bird Survey for 46 species of passerine and near-passerine, including residents, short-distance migrants (wintering in continental Europe) and long-distance migrants (wintering in the Arid and Humid Zones of Africa).  Overall, they found that species breeding in Scotland are generally doing better than those in England, with several species either declining in England but increasing in Scotland, or increasing in England at a slower rate than in Scotland.  These differences were especially stark in long-distance migrants, and in particular those that overwinter in the African Humid Zone, with species such as house martin and garden warbler strongly increasing in number in Scotland only.

Taken together, these results illustrate how population trends can be affected by interactions between breeding season processes, wintering conditions, and the costs of making long migratory journeys.  While many migrants may be facing increasingly tough conditions outside the UK, it is likely that these costs are being offset by better breeding conditions in Scotland than in England, which could be related to differences in land-use between the two countries (e.g. lower agricultural intensification in Scotland than in England). Further exploration of such geographical variation is essential to properly understand the demographic processes underpinning population trends of these migratory species, many of which breed in Jersey, are in marked decline and are on the Jersey bird Red List.

From American Bird Conservancy and Buglife UK

As part of a study on impacts from the world’s most widely used class of insecticides, nicotine-like chemicals called neonicotinoids, the American Bird Conservancy (ABC) has called for a ban on their use as seed treatments and for the suspension of all applications pending an independent review of the products’ effects on birds, terrestrial and aquatic invertebrates, and other wildlife.

“It is clear that these chemicals have the potential to affect entire food chains. The environmental persistence of the neonicotinoids, their propensity for runoff and for groundwater infiltration, and their cumulative and largely irreversible mode of action in invertebrates raise significant environmental concerns,” said Cynthia Palmer, co-author of the report and Pesticides Program Manager for ABC, one of the USA’s leading bird conservation organizations.

ABC commissioned the 100-page report, The Impact of the Nation’s Most Widely Used Insecticides on Birds, that reviews 200 studies on neonicotinoids including industry research obtained through the US Freedom of Information Act. The report evaluates the toxicological risk to birds and aquatic systems and includes extensive comparisons with the older pesticides that the neonicotinoids have replaced. The assessment concludes that the neonicotinoids are lethal to birds and to the aquatic systems on which they depend.

“A single corn kernel coated with a neonicotinoid can kill a songbird,” Palmer said. “Even a tiny grain of wheat treated with the oldest neonicotinoid — called imidacloprid — can fatally poison a bird. And as little as 1/10th of a neonicotinoid-coated corn seed per day during egg-laying season is all that is needed to affect reproduction.”

The new report concludes that neonicotinoid contamination levels in both surface- and ground water in the United States and around the world are already beyond the threshold found to kill many aquatic invertebrates. Data on surface water contamination from surveys to date, most notably from California and from the Canadian Prairies, indicate that concentrations of several of the neonicotinoid insecticides are high enough to be causing impacts in aquatic food chains. Data from other jurisdictions such as the Netherlands show even higher levels of contamination.

Neonicotinoids’ toxicity to bees and other insects has brought them the most attention thus far and has dominated recent concerns of regulatory institutions worldwide. The serious risk to bees should not be understated, as one-third of the US diet depends on these insect pollinators. The ABC assessment makes clear, however, that the potential environmental impacts of neonicotinoids go well beyond bees.

Buglife UK  have added that “This highlights the poisonous nature of neonicotinoid insecticides, environmental concerns go well beyond pollinators. They can persist in the soil for many years, leach into aquatic ecosystems and affect birds and mammals. One of the reasons neonicotinoids are so commonly used is because they are promoted as being non-toxic to vertebrates, but this study shows that claim to be false”.

This report has been released shortly after the European Commission failed to agree on a proposed ban on three of the most commonly used neonicotinoids– imidacloprid, thiamethoxam and clothianidin. Representatives from Member States met to discuss a significant ban after the European Food Safety Authority identified a ‘high acute’ risk to honeybees. However, with five countries abstaining from the vote, including the UK, the ban failed to go through.

Buglife said “The ban proposal will now go through the appeals process with the European Commission free to ban the insecticides unless Member States reach a compromise within two months. I am sure that the European Commission will take note of the recommendations of this significant report when making their next decision and enforce a robust ban”.

It should be noted that in Jersey itself, very few of these products have ever been used. However, their use outside of the Channel Islands will undoubtedly have a bearing on our wildlife too.

The ABC report can be downloaded free here

BIRDS ON THE EDGE has highlighted the threats to our finches and other songbirds from diseases such as the parasitic trichomonosis and avian pox being spread among the birds. The larger population consequences of these parasitic diseases, however, are rarely documented. A recent study in the journal Ibis has looked at the extent to which the trichomonosis epidemic affected the Finnish population sizes of European greenfinch, chaffinch and a control species, great tit, and the body condition of greenfinches.

The disease was first documented in Finland in 2008 and epidemics were observed mainly in south-western Finland. Greenfinches showed a significant decline of 47% in breeding numbers and 65% in wintering numbers in southern Finland during 2006 – 2010. Breeding chaffinch numbers showed a slight decline (4%) during the same study period that was significant only in central Finland. Great tit did not show a significant change in breeding numbers. During the initial disease epidemic the body condition of all demographic groups of greenfinches decreased equally, suggesting that the disease was not selective in respect of age or sex. There were no encounters of Finnish ringed greenfinches or chaffinches in the UK, which could indicate that the parasite has not necessarily been transferred directly from the UK, but perhaps by migrants from Sweden and Germany.

In conclusion, the Finnish greenfinch population has faced rapid and severe population decline due to an epidemic of finch trichomonosis, but the effect on chaffinches has been minor. The decline of greenfinches has been greater than in neighbouring Sweden and of the same order as in UK, where the epidemic was first observed. The study further emphasizes the importance of annual monitoring schemes now and especially in the future in order to detect rapid population changes in common bird species that may be caused by disease epidemics. Bird counts in Jersey have repeatedly shown a very rapid and dramatic decline in numbers of greenfinches in recent years.

From Living Islands: Live

In March 2013 one hundred and seventy-five pairs of Atlantic puffins will return to the small island of Burhou which is situated two kilometres north-west of Alderney to breed. The seabirds will live and raise their young on the rocky coastline for a few months before they return to sea with their young, in the puffin’s case their ‘puffling’ chicks.

To record this amazing passage of events the Alderney Wildlife Trust and South East Grid for Learning Associates will be using state of the art technology from ITV Channel Television and Sure to enable pupils in schools to follow the story in their classrooms and at home.

A Puffin Season on Burhou is an exciting project offering schools in the South East of England and the Channel Islands the opportunity to bring the fascinating life of the puffin live into their classrooms. Using the charismatic puffin as a focal point, this project links directly to the Keystage 1 & 2 curriculum, and is an effective way of teaching Science and Literacy skills, and promoting pupil creativity. This website will provide schools with daily 24 hour updates, live streamed video and a range of other excellent features to keeps schools and pupils informed about developments on the island of Burhou.

Teaching & Learning Resources

To support the project teachers and pupils will be able to access and download a range of excellent Teaching & Learning resources from the project website. Schools can opt to follow the 12 week project plan or select activities from the project menu. Designed for use with Key Stage 1 and 2 pupils these include:

• Science activities linked to popular topics including adaptation, life cycles, food      chains, habitats, caring for the young and conservation and protection
• Daily and weekly mathematical data providing pupils with information about puffin numbers, frequency, location, climate and daily weather reports
• Literacy activities – including opportunities to work with our project author
• Geography & History – Information about the relief, climate and history of Alderney
• Plus Art/Design and ICT activities for pupils of all ages.

Interested in taking part in this exciting science based project?

The project will commence at the start of the Term 5 and run until the end of the first week in July.

Please note, spaces for Channel Island schools are now fully booked. If you would like to be kept informed about the project please contact Living Islands: Live