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South West Peregrine

Cornwall & Devon Peregrine Falcon Study Group since 2007

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A Cornish buzzard study

In early August this year I finished five months of fieldwork studying the breeding biology of the common buzzard. Over this period I located the nests of 36 buzzard pairs and followed their fortunes through the breeding season until they either failed or fledged. ‘South West Peregrine’ have kindly asked me to write a little about this monitoring project and the aims of the research.

Two Young Buzzards
Two young buzzard chicks with the remains of a squirrel in the nest

To start, a little about me. I have been interested in buzzards since first being introduced to the world of raptor research by BTO ringing trainer David Anderson during my MSc. One of the things that attracted me to studying this species was that, considering that they are one of the most abundant large predators in the UK, these birds have been little studied. Buzzards are also an excellent model species to investigate wider questions concerning predators and prey selection. In 2013 I was given the opportunity to come down to the Cornwall campus of the University of Exeter to study for a PhD with the supervisory team of Professors Robbie McDonald, Stuart Bearhop and Steve Redpath.

George Swan
Myself at one of the nests following ringing. You quickly get used to heights when working on buzzards, this nest was 50ft high and the tree was swaying horribly.

One of the areas that we are interested in is how buzzards, with such a broad dietary range, decide what to hunt given that each prey species will require different searching, hunting and handling strategies. Ultimately it would be great to try and answer the question: do individual buzzards display preferences for certain types of prey? These are known as foraging or dietary specialisations. There has been anecdotal evidence of this from elsewhere (see this BTO blog from earlier in the year). The observation of individual foraging specialisations would create further questions, for example: what are the costs and benefits of specialising against staying a generalist? The question of whether buzzards specialise on certain prey is also pertinent to the on-going debate surrounding buzzard predation on released gamebirds. Impartial evidence as to whether these specialisations exist and how they develop may help inform this debate.

Three chicks and Rabbit

A chick with it’s back to food is a rare sight on any buzzard nest, to have three chicks ignoring food is quite remarkable. This pair of adults achieved it by bringing in lots and lots of rabbits. Here, the female is standing on a pile of three young rabbits all brought in over the last few hours.

In order to look at dietary specialisations in a predator you need to understand two things: (1) what they could eat (prey availability) and (2), what they are or have been eating (diet). Although there are various methods to estimate the abundance of prey species, observing the diet of known individuals can be very difficult. The great thing about buzzards is that during the breeding season they bring prey back to the nest whole. This allowed us to explore the diet of different pairs through both the prey remains found on the nests and through recording the adults returning with prey using surveillance equipment.

OLYMPUS DIGITAL CAMERA

One of the nest cameras in action

While collecting this information, the welfare of the birds was paramount. To ensure there was no danger of chick explosions (when the chicks fly from the nest early due to disturbance) we gave ourselves a conservative ringing window of 8 days when the chicks were between 18-25 days old. To further minimise harm we also avoided any work in wet or cold weather conditions. This meant that all the sunny days through June and July I was racing round as many nests as possible ringing the chicks and setting up cameras. Now that it’s over, I can look back on the 2015 field season with rose-tinted glasses but at the time it was hard work!

Snake eggs3

 Watching buzzard nests over hundreds and hundreds of hours of video you get to see some pretty interesting things. Here the female had bought a large grass snake back and proceeded to feed the chick the 10+ eggs she pulled out of it!

The following month was spent lugging huge batteries around the Cornish countryside to keep the cameras running. One of the nice things about our cameras (Supplied by Mike from HandyKam.com) was that the recording box was at the bottom of the tree. This reduced time spent near the nest during the weekly battery changes. The cameras recorded footage every time a chick or parent moved on the nest. Within a month I had over 200,000 videos, consisting of over 4000 buzzard hunting hours and over 1500 prey item deliveries. I don’t want to give too much away here as I’m just starting to analyse the dataset but I’ve included some nice snippets from the footage above. If you’d like to see some more nest camera highlights you can find them by searching #buzzarddiet on twitter. I’ll keep SWP posted with further results as and when we publish them.

In the mean time, we colour-ringed over 40 chicks with an orange ring with a 2-digit code on their right leg, if anyone spots one of these birds please get in touch g_swan@exeter.ac.uk

George Swan

Three birds

Both Adults on the nest present a chick with a mole.

“If you’re interested in this study, here’s a link to George’s 2011 MSc Thesis on buzzard breeding ecology in Scotland. “

Thesis

Rory Carr – Bird of Prey Collection

From an early age Rory Carr 27, has been fascinated by wildlife, particularly birds and insects. It is perhaps unsurprising then that the natural world has become a major influence and source of inspiration for this up-and-coming artist. He is currently putting together a British Birds of Prey Collection.

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Rory works primarily in watercolour, but prepares his work by first drawing the subject using pencil. Once painted, he adds extra definition and emphasises areas of texture using ink which serves to strengthen the composition. This multi-disciplinary approach, combining drawing skills with wash techniques, Rory has developed while working towards his A-level in Fine Art at Kelly College.

During his school years he studied the famous wartime artist John Piper and Robin Armstrong, a local well-established wildlife artist who also works mainly in watercolour. As well as working towards a career as an artist, Rory is strongly motivated by wildlife conservation efforts and has trained as an ecologist, having graduated from the University of Reading with a Master’s degree in Species Identification and Survey Skills. Rory hopes that his work will help to reconnect people with nature by encouraging an awareness and respect for the countryside and its wildlife.

For more details on his work, prints and commisions, you can contact Rory by visiting his Facebook page Rory Carr – South West Artist

Birders Against Wildlife Crime

This months guest article comes from Charlie Moores. Charlie is a founding member of a new organisation named Birders Against Wildlife Crime(BAWC). In his piece, he explains the reasons why he and like minded friends felt the need to create the group.

The answer to why ‘Birders Against Wildlife Crime’ and other good questions. Just last month thirteen birds of prey were found dead in a two square mile area of the Scottish Highlands. They’d been poisoned. The majority were Red Kites, presumably part of a re-introduction scheme championed by the Scottish government and bitterly opposed by some agricultural and shooting interests. Amongst birders the reaction to their discovery ranged from outrage and a determination to catch the criminal(s) involved to a weary cynicism that no-one would be caught, ranks would be closed, and nothing would change.

There have, is the perception, been too many incidents like these and too few prosecutions. One poisoning incident is of course one too many, but despite what many birders might think our birds are well-protected. On paper anyway. In fact most of our wildlife is protected by hundreds of laws that have been hard fought for and which cover everything from poaching freshwater mussels to knocking down House Martin nests over a homeowner’s front door.Having so many laws brings its own problems though. Very few of us know or understand them. They are complex, there are numerous exceptions, and they’re not the same in different parts of the UK. Few birders (few people anywhere) wouldn’t recognise that using poisons to kill protected birds is a crime, but not all laws that impact wildlife are so clear-cut. Is it legal to use a dog to hunt rabbits, for instance? How would you recognise when a cage trap is being used illegally? How about taking a photograph of a roosting bat – is that legal or illegal?

Most of us don’t want to just see wildlife, we want to stop other people breaking the laws that protect wildlife as well. Compared with the poisoning of a Red Kite, for example, a council worker cutting back a hedge in the nesting season might seem almost unimportant, but more birds must be lost to casual nest destruction every year than are lost to poisoning. If we understood the laws relating to nests and eggs would we not be in a better position to change Not only are many of us unsure about the law, we’re also not sure what to do if we witness a crime or find a crime scene. If we had found one of those poisoned Red Kites what should we have done? What information should we record? As importantly, who should we tell: the police, the RSPB, a local wildlife trust maybe? All of them perhaps.There will be readers of this article who’ll be saying to themselves, sure, but that information is available on numerous websites. That’s true. So why did we think we needed to set up Birders Against Wildlife Crime (BAWC) anyway? Because while the information is available, it’s often very hard to find. Most organisations that cover wildlife crime are concerned with numerous other issues too. The specific fact we want may not be buried, but it’s rarely standing in the open either! As proof of that the birders who set up BAWC have well over a hundred years of birding experience between them, but – like most birders we know – couldn’t have answered every question in the last few paragraphs either.

So what we’re doing (‘doing’, note, not ‘done’ – this is an ongoing project) is to put all the information we need, written in plain English, in one place. We want to help make tackling wildlife crime as natural as picking up a pair of binoculars, so everything we’re doing is guided by one prevailing thought: we’re birders, we’ll be using the website, how would we want the information laid out so that we can get our questions answered quickly and easily?
On top of that we want BAWC to be an effective campaigning group. We don’t have members, we’re totally independent, and we’re not bound by charters. We’re free to ask the questions that some other organisations can’t. Why do birders feel that no-one will be held to account when Red Kites are poisoned? Why is that many birders feel that even if they do report wildlife crime nothing will be done? And if someone is caught, why are punishments often so insignificant?

There are a lot of questions to ask. And we’re not saying we have all the answers. Between us we do though. The expertise and knowledge held by groups like the South West Peregrine Group is invaluable. We understand that no-one has the right to simply turn up and ask for that knowledge, so we’re working hard to build relationships, to work alongside other organisations. We know it’ll take time, but we can help and promote each other. We can all benefit from that. Much more importantly though, our wildlife will benefit. If every time birders went into the field – wherever they were – they were looking out for wildlife crime and feeding information to the right people imagine what we could achieve. We will never be able to stop wildlife crime (we’re dreamers at BAWC but we’re not deluded), but if criminals knew that birders were on the look out for them, knew what to do if they saw a crime, and had the information at their fingertips to get that crime reported to the right people every time…

We may not be able to stop every crime from taking place, but we can help tip the balance back in favour of our wildlife. We can make it so that criminals are looking over their shoulders all of the time, that wildlife crime becomes a higher priority than it is now, and that when a criminal is caught it matters to them. Why did we set up BAWC? The simple truth is that we’re birders and we’re sick of crimes against our wildlife. We think we can make a difference. And we are determined that we will.

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