Searchline. Let us do the hunting whatever expert you need. Please call our free SearchLine today on 0161 834 0017

Journal Detail back to listing

Birds in the Legal Environment - The Expert’s Role
  • Mar 11, 2020
  • Latest Journal

Ask the average person is there any structure or order to what goes on amongst birds in the natural environment, and most will suggest it is nothing but chaos. The reality being that most people have little understanding of the important biological place these feathered creatures have in the world that we and numerous other animals and plants share.

It perhaps comes as a surprise then to discover that the UK has some of the most rigorous and all-embracing bird protection legislation in the world, most present EU legislation being based upon the UK original. Did you know, for example, that in the event of possession of any bird, egg or derivative, it is for the person involved to prove that possession is lawful (Kirkland v Robinson). That same legislation empowering the courts to impose either a fine, custodial sentence, or both and prohibit individuals from any further keeping of birds.

So then, are we protecting birds as individuals, or as a biological unit, and if the latter then how much do we already know about them. Well we know an awful lot actually, and in considerable and often intimate detail. Commencing with the various fossil periods on into more recent history, the early literature being littered with references to their activities. However, by around the mid-1700s two distinct branches of zoology were emerging, one regarding the all-important international scientific names attached to plants, birds and other animals, the other increasingly focused on fieldwork.

The still ongoing argument over species’ names and their position in the list focuses primarily upon often obscure biological relationships, being made easier and at the same time more difficult by the recent introduction of DNA sampling into the equation. However, that very much remains a ‘committee’ matter.

Not so though questions like where precisely in the world do the ten thousand or so known bird species occur, and more interestingly why? Or where, when and how do they breed, and are they always successful, or if not then why? Plus, numerous other seemingly impossible questions, like why only some species migrate and even more interestingly, how do they navigate – there and back. The bottom line being that we now either know all this, at least in broad terms, or are on the edge of discovery, literally in a world context. Certainly, within the Western Palearctic (from Britain, France and Spain east to central Russia) you probably cannot find one single bird species that has not been the subject of some level of specific study.

As just one quick example of what is going on world-wide, experienced field workers conduct monthly waterfowl counts at dedicated sites throughout the UK and Ireland. Consequently, we know that in winter 2017/18, 12.8 million ‘waterfowl’ comprised 4.9 wading birds, 3.8 million gulls, 2.1 million ducks, 1.1. million geese, 5000,000 rails, 170,000 cormorants, 70,000 swans, 60,0000 herons, 30,000 divers and 30,000 grebes. A substantial proportion of which in summer breed over vast areas elsewhere in Northern Europe and beyond, which we know from either ringing recoveries or satellite tracking data.
In the wider avian context this is supported by broader, all-species all-activities studies allowing us to unravel the life histories of birds and many other animals in intimate detail. Enabling us to know that in just my lifetime many former common UK and European bird species suffered population declines of up to 90%, and just for the record I helped thousands of other fieldworkers gather those data. Even more worryingly these declines continue, further significant levels of reduction applying to each subsequent survey period. And so too in North America, where a reported three million fewer birds exist than in 1970, including a 53% decline in grassland birds. All of this raising some seriously important questions about our own part in both the cause and of course its ultimate effect upon all of us.

The important point being that internationally we now use pretty much all our wild bird populations as biological sampling tools; as with the canaries once used down coal mines – when they drop off their perch then it’s time for us to start worrying.

UK legislation seeks to address these now very concerning bird reductions from two directions; firstly, by protecting birds as individuals, including their nests, eggs and young and in addition such things as international movements, and secondly by protecting their habitats.  The first of these largely via criminal statutes, unlike habitats, which involve generally far more complex issue, particularly in the agricultural community, which in turn are tied to human population growth.

As a former sixteen-year RSPB prosecutor and investigator and a subsequent courtroom expert, my professional experience involves both of these two legislative options. My specialty lying in examining any alleged unlawful or damaging human activities and comparing them against an absolute wealth of biological and behavioral information. Importantly, though, in the neutral and unbiased manner now demanded of all courtroom experts, being required to critically examine the evidence offered up by both sides, regardless of who employs me.

I can perhaps best demonstrate how this works by quoting just two or three such cases.
Captive Bred Goshawks. One form of legislative abuse involves the theft of eggs from nests of wild birds in order to hatch them and falsely claim the resultant young were lawfully ‘captive bred’. A situation frequently involving specially protected biologically valuable birds of prey e.g. Peregrine Falcon, or Northern Goshawk, and made more worrying by much evidence of eggs being unlawfully moved between countries on a world scale. The above-mentioned Kirkland enquiry commenced with four Goshawk eggs in an incubator; eggs that clearly were from a Goshawk, but not supported by the ‘breeders’ otherwise detailed written records. It was a protracted and complex investigation spread over eighteen months, involving the eggs hatching and the subsequent young going to Kirkland and being falsely registered with the then DoE as captive bred, before selling them to other bird keepers.


Northern Goshawk is specially protected in the UK by its inclusion in Schedule 1 to the Wildlife and Countryside Act 1981. It is a forest predator occurring throughout the northern hemisphere, from Britain east through Russia to Japan and across Canada, south as far as Corsica, Sardinia and Mexico, involving ten or so biologically recognizable sub-species. Within the Western Palearctic Goshawks tend to be shorter winged and darker-plumaged travelling from north-west to south-east, wing length having much to do with the fact that northern populations are necessarily migratory (the northern forests freeze in winter). In addition, DNA and other studies show we might reasonably expect the progeny of any one pair of birds to demonstrate the same biometric and plumage features as their parents. The two alleged parent Goshawks in our investigation showed all the features of northern Scandinavian Goshawks; very pale-grey plumage, with extremely long (top-of-the-range) primaries (the longest wing feathers). But not so the four incubated alleged young, which unlike their alleged parents clearly demonstrated dark, mid- to southern-European plumage, plus shorter wing lengths falling within that same geographical range.


The ‘breeder’ plus his wife were convicted of the possession of wild birds, contrary to Section 1 of the Act; which had recently very much changed the ground rules by making any possession an absolute offence. Both appealed their convictions, only the wife’s being quashed; the implications of that being that the breeder could no longer keep birds, but his wife could. Kirkland was charged with both possessing and selling the four young Goshawks, offering little evidence in the lower court and appealing his case directly to the High Court in a challenge to the reverse burden of proof. The appeal was finally heard in December 1986, two and half years after we first found the four Goshawk eggs. What the Kirkland case did of course was finally prove that Section 1 of the 1981 Act means exactly what it says, the wording of the High Court’s judgement leaving no doubt what Parliament and the Courts think of the need to protect our wildlife.

To a considerable extent the outcome of the Kirkland investigation revolved around an ability to (i) correctly identify both the two birds (including their racial features) and the eggs involved, (ii) understand and correctly interpret the defendant’s notes and dates on breeding behavior, (iii) understand crucial species’ geographic size and plumage differences, and (iv) be able to both catch up and handle two aggressive and valuable large birds without damage to either the birds or ourselves and reliably obtain the necessary measurements. Obviously, evidence like that could be used to either prove or disprove such an allegation.

Cruelty to Captive Birds. I was the recent defense expert in a cruelty accusation relating to two Harris’s Hawks (Buzzard-sized hawks from Central and South America) kept tethered indoors The suggestion being, (i) that the birds had no permanent access to drinking water, (ii) two ferrets in a nearby cage suffered mentally from being able to see the predatory birds, and (iii) the two birds suffered a health risk owing to accumulations of their own feaces. I pointed out that although both I and those in court might not tolerate the fecal accumulations and that I accepted there might be a human health risk, there was nothing in the photographs outside my normal experience as far as the way the two birds were being kept. And that in any event unlike birds in general, most birds-of-prey normally drink very rarely, perhaps due to the level of moisture present in their wholly flesh diet.

However, it was the allegation that ferrets might suffer mental cruelty from the mere visual presence of live birds of prey that interested me most. There is a long-standing UK prohibition on the use of live birds and other animals as bait when catching other birds. Presumably to prevent harm to those same captive birds or other animals, unlike in South Africa where such use is lawful. I recently spent time in that country helping catch various eagles and other large predatory bird species to both take valuable data and attach metal leg rings for future identification. We accomplished that via a portable, small-mesh wire-covered cage containing two live mice or gerbils, the trap being covered outside with nylon nooses that catch the eagle by the feet; note though that the eagle cannot get at the animals inside. I was particularly struck by the behavior of these small animals inside the trap, who routinely ran towards large predatory birds like African Hawk Eagle (birds we ourselves handled with great caution) as they landed next to the trap. It was perfectly obvious that the mice or gerbils had absolutely no idea of the danger these eagles presented, regardless that this was perhaps the second or third time the same two animals had been in the trap when eagles were caught. For certain there was no suggestion animals in the trap suffered any visually obvious form of mental stress. But if you were a mouse born in captivity from generations of mice from a similar background, then why would you?

When Was the Bird Hatched? In a similar vein, I was recently asked by the defense to comment on the evidence in a case where a bird of prey keeper was found to have an obviously less then twelve month old Peregrine Falcon, but nevertheless wearing a closed metal ring issued in a previous year. A ring showing no visual evidence of having been fitted illegally, the only obvious possibility being that it had been fitted to the bird that year whilst it was still at the ‘nestling’ stage. It could also be shown that the ring in question had previously been registered with the now DEFRA as having been fitted to a bird in the defendant’s possession in a previous year, but that was now dead; a bird that would by now very obviously have been in full adult plumage.

Much of the discussion revolved around who might have fitted that ring to the bird. All I was able to say in evidence was that if the facts as I understood them were correct, then the ring had to have been fitted within a period of mid-June to mid-July, regardless of where the bird originated from or who fitted it.

Possession of Small ‘Passerine’ Birds. Most small finches and songbirds belong to what we call the passerines or perching group of birds. Large numbers of people keep either various canary types, e.g. borders or lizards, or the smaller and commoner British and European finches, e.g. Goldfinch, Greenfinch. A big part of that interest has to do with the skill and care involved in getting the birds to breed in captivity, or an even greater skill in obtaining hybrid young from mixed-species pairs.

One enforcement problem comes from the fact that it is possible to catch these British birds from the wild and illegally sell or exchange them as genuinely captive-bred individuals. And it does happen. Given the change in the offence of possession brought about by the 1981 Act, you might think that from an investigator’s viewpoint the situation is greatly improved, but what if the bird is claimed as a ‘foreign’ species. Or worse still, really is a hybrid between two different species, given the minimal chance of such a bird occurring in the wild.

Another concern here is the statutory requirement that bird species of the kind we are discussing cannot be sold alive unless they were both lawfully bred in captivity and have on one leg an official close-fitting metal ring of the correct size and type. Meaning that in cases of sale or intended sale we need to address at least four issues for each and every bird involved; (i) is it a wild bird within the meaning of the Act, (ii) is it a species that can be sold, (iii) are there any indications that it was not bred in captivity, and (iv) does it have on a close-ring and if so, are there any suggestions it may have been fitted unlawfully?

I already mentioned one possible pitfall in identifying captive birds, but what about physical features? Or ring condition? In an ideal world everyone keeps their captive birds in top physical condition, with no feather out of place. So, in that same ideal world it should be possible to readily identify birds with broken feathers or soiled plumage as perhaps taken from the wild. However, we need to be extremely careful in trying to broaden any ‘poor bird-keeping situations’ into those indicative of birds having recently come from the wild. Plus, we perhaps need to take into account the fact that we have probably just spent thirty minutes, as a stranger to the birds, chasing them around a wire-netted aviary in order to catch them for examination, and be extremely cautious about where to attribute any feather damage or physical injuries.

Close-rings and their condition are a subject on their own. The small metal close-rings fitted to the kinds of birds we are discussing here come with carefully manufactured internal diameters and need fitting to one leg of nestling birds whilst they are still around half grown (around day seven of an average fourteen-day fledging period). Beyond that time the ring cannot be fitted without likely visible damage to the bird’s leg, and neither can it be removed without showing similar evidence. Unlawful methods of getting around that problem include either fitting an incorrect ring of a greater diameter or using a suitable lubricant to force the ring onto the leg, both of which should be detectable via expert examination.
Frequently, though, rings are forced on to trapped wild adult birds with little regard for any damage to the bird, often accompanied by obvious attempts to increase the internal ring diameter. Resulting in another example of where an understanding of aging according to plumage phases might assist the evidence - as with a bird very obviously hatched last year or before, but wearing a ring issued during only the current year.

Possession of Birds’ Eggs. Another legal minefield demanding a particular type of expert. Take for example a collection of eggs found during a police raid, say for drugs. On the face of it there is already an offence of possession, but only if the eggs involved are from bird species occurring naturally in Britain or Europe. So then, what might our man say in response to the obvious questions? Well he might suggest they are not the eggs of British or European birds, and to be fair there are numerous ‘look-alike’ species out there; Stone Curlew is specially protected and breeds scarcely in both Eastern England and throughout southern Europe and beyond. However, its eggs closely resemble those of Senegal Thick-knee and several related African and Australian species. A problem that also occurs commonly amongst ducks, geese, herons, birds-of-prey and the numerous parrot species, again worldwide and to name just a few.

In this type of case the investigator is not so much interested in the eggs as in any notebooks, paperwork, maps and diaries, plus whatever we might find on the computer. But I suggest there are two things above all else to look at in this situation, starting with the bookshelf. I have heard it suggested that the contents of a person’s book collection present a shortcut into their mind; as with numerous books on nests and eggs where the owner claims no interest in birds.

What we really need to unearth and examine, though, are either data cards or some other recording method detailing when and where these eggs were collected, and hopefully by whom? Most illegal collectors maintain such records, so find these and further discussion may be unnecessary, though the absence of such records does not necessarily work to the suspects advantage, nor does it prove they are non-existent. However, in the absence of any other evidence, just charging the man with possession of eggs may be inviting him to come up with a range of answers it takes an expert to respond to. And even if it does seem that any eggs involved are from those non-European species, we should not dismiss the possibility of the defendant being guilty of import offences.

Profile: After leaving school Peter Robinson worked for a time with a company importing live wild birds from just about all corners of the Earth; before we all realized the extent of the damage we were doing to the planet. He then spent eleven years in the London Fire Brigade, rising to the rank of Station Officer and becoming a Graduate Member of the Institute of Fire Engineers. However, his continuing background interest in birds resulted in him making the change to Head of Investigations with the Royal Society for the Protection of Birds. A position he held for sixteen years, also acting as the Society’s prosecutor and successfully taking several cases to the High Court on appeal, including the Kirkland case already referred to. Early retirement over fire service pension issues saw him switch to Courtroom Expert Witness, having now given evidence in all four UK countries, plus High Courts in both England and Northern Ireland. Peter is a Fellow, Honorary Life Member and former Principal of the Institute of Professional Investigators and a former member of the World Working Group on Birds of Prey. He is author of the books Bird Detective and The Birds of the Isles of Scilly, plus the recent fictional (related to bird smuggling) The Consequences of Finding Daniel Morgan. Peter has ‘bird-watched’ in some forty countries on six continents and has personally seen around one quarter of the World’s bird species in the wild. On behalf of the British Trust for Ornithology he has captured and ringed some 50,000 live birds and submitted records for 30,000 nests of over one hundred UK species. His personal fears include snakes and ‘big cats’.

Peter Robinson