"Sparare sulla croce rossa... " - The Knepp Stork project

When I was a teacher of Environmental Science in an international school one of my favourite games was hearing literal translations in other languages of expressions used to explain a particular concept. For example, anyone English understands the question: "Were you born in a barn?" said to someone who leaves a door open on a cold day. In my part of Italy that phrase is "Were you born on a boat?" (not surprising in a major port) while the Chinese (and, oddly, according to my students, the people of Sarajevo) ask "Were you born with a tail?", the implication being that you can't shut the door because your tail is still outside. One Italian expression I haven't found a convincing English equivalent of is to "Sparare sulla Croce Rossa..." - literally "Shooting at the Red Cross", i.e. attacking or criticising an act or person that is - in the eyes of others - beyond reproach.

Anyone who reads this blog will probably have realised that I am something of a contrarian on many matters to do with the environment. I don't do that for the sake of being awkward but out of a sense of deep conviction and because I'm free to do so, not having an employer who might want me to toe one particular line or other. I've already written blogs or tweeted about why I am unhappy about the orthodoxy surrounding the calls for a ban on driven grouse shooting, the withdrawal of the general licences for avian generalist 'pest' species, wide-scale and ill-considered tree-planting on marginal land and the current mania  for "rewilding". When I talk to other people (for example at the Bird Fair the other day) I do encounter people who broadly agree with my position but can't speak out for fear of a charge of heresy and risks to their employment or 'marketability'. 

One of the stories that has irritated me over the last couple of years (since I first read about it, in fact) has been the (so-called) "reintroduction" of White Storks at at the Knepp Estate in West Sussex: "Last week 24 juvenile White Storks were released (there), after the initiative to restore the species to southern England took a significant forward step." "The project aims to establish at least 50 breeding pairs in southern England by 2030 through a phased release programme that will take place over the next five years."

The techniques to the species' establishment in new areas have been tried and tested in Europe over at least forty years and "new" "self-sustaining" (my italics) populations have been established in various countries in Europe including (to my knowledge) the Benelux countries (with birds nesting across international borders), France and Italy and perhaps elsewhere too.

I live in a part of the world that is only 50km west of the White Stork's natural range in Slovenia and 50km south of a White Stork "reintroduction" project so I'm well placed to follow some issues involved and the pitfalls surrounding this type of project. After he posted various announcements about the plans I tweeted to Prof. Alastair Driver, asking for detailed information surrounding the project but received no reply. I'm sure he just didn't see it.  I'm very grateful to Derek Gow for supplying that information and giving me pointers as to where I might find more details regarding the background, justification for and implementation of the project.

  

But why would anyone be irritated by such an apparently laudable project? Why would anyone fire on the Red Cross. Well ... here are a few reasons: 

• At best the species is tenuously native.
• The reasons for its extinction may have been partly natural - and perhaps partially persist.
• No permits were asked for and none were needed it would seem.
• No environmental impact assessment of the introduction was carried out.
• There may indeed be impacts upon pre-existing native wildlife.
• The birds and any "self-sustaining" population will be dependent upon hand-outs and remain thus if animal welfare issues are to be avoided. 

Lets deal with these issues one at a time: 

• At best the species is tenuously native.

To their credit the project's proponents do a good job with presenting the evidence of various toponyms, the fossil record and the bird's status since the dawn of scientific recording during the Renaissance. You can read it here.

Apart from the incontrovertible, famous  and widely-documented nesting on Edinburgh cathedral in 1416, though, there seems very little to suggest that White Storks were a regular feature of the British and Irish landscape in the last millennium and perhaps (and only perhaps) a minor element in the preceding one. The evidence for the latter is scant, with a few bones here and there in Saxon middens. The document makes much of the repeated representations of White Storks in pre-Renaissance and pre-Reformation religious art but does not seem to look at this unduly critically, presenting it as evidence to suggest (it would appear to me) that the birds were present in Britain because the monks had seen them. It seems to imagine a Britain cut off from the continent, a Britain that had taken back control of its religious iconography but throughout the Middle Ages Britain WAS connected to the continent by trade, migration and particularly by religious diplomacy. Bishops and cardinals moved around Europe, from one posting to another, together with their enormous retinues like Medieval rappers, which I suppose they were in some respects. Pope Adrian IV, for example, was born Nicholas Breakspear in Abbotts Langley in Hertfordshire. So any illustrations of storks and stork-like birds may well have been seen by the illustrators or their supervisors where they are naturally present today, in the ultra-Catholic Holy Roman Empire, or Spain or even as close by as  pre-Reformation Denmark or the Netherlands where we know they bred in large numbers.

• The reasons for its extinction may have been partly natural - and partially persist.

I have to state a personal stake in this. I once co-wrote a paper on an ecologically not dissimilar species (a non-passeriform trans-Saharan migrant), now extinct in Europe and being reintroduced in various countries, sometimes accidentally and sometimes by design: the Bald Ibis (Geronticus eremita). (For what it's worth I've been equally forthright about one of the schemes that foresees its reintroduction in Austria and re-establishing its migration between Salzburg and Tuscany in Italy). From early Renaissance scientists (Conrad Gessner (1513-1565, and Ulisse Aldrovandi 1522 - 1605) and iconography, later backed by archaeological excavations ... so basically the same tools used to justify the White Stork reintroduction... we know that the species nested in Europe as far north as Salzburg in Austria until some time around 1600. It seems to have disappeared rapidly after that date and we know that, like White Stork, the species nested in association with people (on the city walls of Salzburg, Gessner tells us as much) and was taken for food (the bones were found in the middens of Medieval Salzburg).

That said, the manner of its vanishing was very rapid. Several factors seem to have been at work including depopulation as a result of the Black Death (which would have covered much of its feeding-grounds with rank grass and scrub (a negative effect of proto-rewilding) and the fact that Europe underwent a period of poor summers and bitterly cold winters, the Little Ice Age, between about 1300 and about 1870 but peaking in intensity around the time of the Bald Ibis's disappearance from Europe.

But another element in addition to poor climate and persecution is possibly key to the disappearance of Britain's phantomatic White Stork population: sea level rise.

The evidence for White Storks in Pleistocene Britain seems incontrovertible in terms of the fossil record. A fact that seems surprising given the cold temperatures at the time but the species nests as far north as  Estonia and Russia on the southern shores of the Gulf of Finland so perhaps the climate was not an issue. What differed back then was that Britain was joined to continent by a land bridge and was thus until (perhaps) 12,000 years ago. Why is that important? Because White Storks migrate, mostly using soaring flight like raptors, and are loath to cross bodies of water. They did nest in Sweden from the 16th century through to the 1950s (so in the teeth of the Little Ice Age), one imagines crossing the Baltic at the Øresund straight, which at Helsingborg is less that 3km wide ... so essentially no barrier at all. Any migrant stork reaching (or leaving) Britain for France must confront a crossing over water at least ten times that distance. This might not have been a real hurdle for an adult White Stork and "plastic" (sorry, I use the term as shorthand) storks from feral populations in NW Europe now reach Britain regularly but does this strategy perhaps impose losses of juveniles making the journey for the first time, a sort of tax upon reproductive success? Did this "tax" gradually doom Britain's native stork population in the early historic period, and, more importantly, does this biogeographical barrier represent an unresolvable barrier to the recreation of a truly wild, migrant White Stork population in Britain? White Storks CAN and DO cross much larger water bodies (Swedish birds have shown this, as much as 200km) but information is lacking about what the associated mortality rates are like. A marked bird which crossed the Baltic to Poland on migration was captive bred in origin and may have had "Eastern route" genes. It was essentially genetically programmed to undertake a do-or-die mission.

• No permits were asked for and none were needed it would seem.

When I criticised the Knepp White Stork project, people said "I'm sure they have all the necessary permits". I asked whether this was the case but didn't get an answer. Derek Gow finally provided me with the information that: "The IUCN Guidelines for Reintroductions set out procedures to ensure that reintroductions and translocations of species for conservation purposes are carried out to high standards. The species is a regular visitor to the UK and the project fulfils all relevant criteria and Natural England and DEFRA confirmed that no licence is required under the Wildlife & Countryside Act (1981) to restore the white stork in England as a breeding species. This project concurs with Article 22 of the European Habitats Directive and Article 11.2 of the Bern Convention."

So. That's pretty clear then. Even though those "regular" visitors are mostly "plastic" storks from W. European projects and that before they began (in the 1970s) White Storks were vagrants to Britain and by no means regular visitors. All above board then. I still think it's questionable.

• No environmental impact assessment of the introduction was carried out.

It was decided not to carry one out. This surprised me and it should surprise you too. An EIA will not prevent something but it will flag up issues that require research or regular monitoring. Some of these are indicated in the main report: 

"White storks are opportunistic feeders and will readily feed on a broad range of small mammals (voles, shrews and moles) are likely to be important especially when food provisioning for nestlings (Chenchouni et al., 2015). Insects (beetles, grasshoppers, locusts and crickets), reptiles (snakes and lizards), amphibians (frogs and newts), bird’s eggs, fish (though they are not a specialist fish eater), molluscs and earthworms (which can form up to 30% of their diet) (Kosicki et al., 2006; Antczak et al., 2002; Hancock et al., 1992), along with various orthopteran (e.g. Boyan, 2013). Earthworms are likely to be a very important food source in Sussex (e.g. Alonso et al., 1991). On occasion they will take the chicks of ground nesting birds and will readily consume carrion (Hancock et al., 1992). Introduced Louisiana red swamp crayfish have become an important food source in Western Europe (Correia, 2001; Negro & Garrido-Fernandez, 2000; NABU, 2013). Storks are well-adapted to exploiting crayfish populations (Sanz-Aguilar et al., 2015)."

The Hare and the Stork - from the web.

• There may indeed be impacts upon pre-existing native wildlife.

While much is made of the Stork's love of alien crayfish, the list doesn't mention Brown Hare (Lepus europaeus) leverets and doesn't list the ground-nesting birds' chicks that White Storks find delicious, including the red-listed Skylark, Lapwing, Common Snipe and Grey Partridge - all present but endangered in Sussex. Obviously reptiles and amphibians are also eaten, in quantity when the opportunity allows. Many of those are red-listed too. The White Stork is not endangered (now) anywhere in its much expanded range. Do we really need more non-endangered things out there potentially eating red-listed species? Aren't there enough already? Another species with very similar tastes which (just about) nests in the Western Palaearctic in Iraq, the African Sacred Ibis (Threskiornis aethiopicus) is the subject of destruction orders in the European Union as it becomes established with resident feral populations now nesting in France, Italy and Spain. Its crime (apart from being non-native) is that it eats ground-nesting birds and rare amphibians. Sounds familiar? The very concentrated population of White Storks near Udine (NE Italy) are unpopular with  local hunters as they regularly predate a few of the main quarry species including Hares (leverets), Ring-necked Pheasants (chicks) and Common Quail. I don't expect sympathy for hunters' tears but very high densities of White Stork are present around the release and feeding sites, densities that are not dependent upon any natural food supply. Any leveret is just a lovely change from slightly-off sprat.

• The birds and any self-sustaining population will be dependent upon hand-outs and remain thus if animal welfare issues are to be avoided.

While the thriving Slovenian population I alluded to above is entirely migratory, vacating the breeding grounds in August and returning at the end of March, the colony at Ciconicco (yes, the toponym means "Storksville" which is why it was chosen),  near Fagagna (Udine) in north-eastern Italy, established under the supervision of my late friend (and co-author of the paper mentioned above), Fabio Perco, is a mix of migratory and resident birds. Some birds do migrate and indeed two ringed youngsters were shot on Malta a couple of years ago, an incident that led to the premature closing of the hunting season that year.

Feeding time at the zoo - White Storks at Fagagna (UD, NE Italy. - from the web.

The birds that do not migrate remain close to the colony and are fed on unsold sprats from a fish-market close to Venice. This incentivises non-migration - why fly to Africa when you might be shot? - and has created a hand-out culture amongst the storks. Stopping the feeding would rapidly deal with the issue but would create animal welfare problems (of starving storks) which makes it out of the question. When birds from Fagagna do wander off, they either return rapidly or end up in care. 

From what I can gather, the Knepp birds will be fed year-round but perhaps not at a single concentrated site. Hooded Crows and (occasionally) Black Kites are an issue at Fagagna. I wonder if similar species (Carrion Crows and Red Kites) will become more common at Knepp with possible knock-ons for other red-listed species on the estate such as Turtle Dove?  

Anyway. I've said my piece. Somebody needed to play the Devil's advocate.  None of the above should lead you to believe that I am against reintroductions per se. Most of those underway, especially those for Wildcats, Pine Martens and Beavers, are long overdue and epistemologically solid. I just didn't feel that a White Stork project was a priority, necessarily philosophically and scientifically justified and without a potential downside as it has been painted. That said, I'm sure the releases will be a runaway success and that a resident, feral and artificially-maintained White Stork population of 50 - 100 pairs will be rapidly established in the south-east of England. I'm just not convinced that it's what was needed at this moment in time. Can anyone argue with that?