as has been pointed out before that doesn't add much...
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Slender-billed Curlew. (1 Viewer)
- Thread starter keith
- Start date
as has been pointed out before that doesn't add much...
Hi Paul!
That hasn't always been the case, at least so says the rumour-mill...
Surely all record assessment is scientific? You are hypothesis testing - and you have some sort of evidence to judge whether or not your hypothesis is true or false...
Rarely is anything 100% proven without a specimen which you can extract the DNA...
And why wouldn't that be a useful exercise, but do all the Euro-experts not buy it?
cheers
Z
That hasn't always been the case, at least so says the rumour-mill...
Surely all record assessment is scientific? You are hypothesis testing - and you have some sort of evidence to judge whether or not your hypothesis is true or false...
Rarely is anything 100% proven without a specimen which you can extract the DNA...
I don't see the point in getting an "independant" committee to assess the record. Who would be on it? Perhaps all the well respected European birders who have already stated they don't think it was one...
And why wouldn't that be a useful exercise, but do all the Euro-experts not buy it?
cheers
Z
Agreed.
Frenchy
Well-known member
Hi Paul!
Hi Z!
I've never seen any evidence or hint that any current member of BBRC lets their personal listing prejudice come in the way of objective assessment. I would hope it would be even less likely on BOURC.
I don't have a hypothesis when assessing a record, unless of course i've already seen photos of the bird online or in the magazines. Or found it myself
Don't agree with that mate. Most species on the British list are easy to identify with 100% certainty. Its just gulls, ducks, flycatchers, waders etc etc that can carry hybrid DNA...
I don't know of any well respected European birder that says "yes, thats a slam dunk Slender-billed Curlew, no problems guv'nor". Do you? There could well be several, i've just not heard any vociferous defense of this bird from the Continent.
You may be right about it being a useful exercise to put the record to a different committee for a few reasons, but it's already going around two committees in Britain, twice! That's 20 different BBRC members and probably 20 different BOURC members (although with some overlap between the two committees). Will it really achieve anything useful to send it to another committee, above giving that third committee a poisoned chalice and many sleepless nights!?
duncan fraser
Well-known member
Committee assessments are always a scientific exercise (unless the committee is completely biased) as they are evidence-based. The committee tests a hypothesis - the identification of the bird - using observations (always a key part of science) made by the observer, and measure ( again, a key process within science) them against known criteria. If the record is accepted, the hypothesis is correct, if not accepted, the hypothesis is falsified.
Of course, science is not perfect (nothing is), and there are a host of problems within it, not least observer bias or committee bias, limited knowledge etc. - but the committee system is certainly a scientific process if done correctly
Of course, science is not perfect (nothing is), and there are a host of problems within it, not least observer bias or committee bias, limited knowledge etc. - but the committee system is certainly a scientific process if done correctly
crabplover
Well-known member
Ok, it's bad video, but at least it's available and out there.........
Where did the L-tS video go?
Andy.
Just grinding out rumours from the past! No slurs on the present bunch!
I don't have a hypothesis when assessing a record, unless of course i've already seen photos of the bird online or in the magazines. Or found it myself
I guess we agree - cf Duncan's post.
Don't agree with that mate. Most species on the British list are easy to identify with 100% certainty. Its just gulls, ducks, flycatchers, waders etc etc that can carry hybrid DNA...
Are, but there is not only the spectre of hybrids - which affect a considerable fraction of our vagrant avifauna, but also observer credibility, photographic artefacts etc which do reduce the objectivitivy of the evidence and thence your P-values... Yes its unambiguously a Catharus thrush but what about that lumberjack shirt....
Maybe not, but many have spent lots of time either looking at live or dead SBCs and thus their word may be 'worth more' than UK committee members that haven't done lots of prior work or had previous experience. Granted they might not be interested...
Z
Paul Chapman
Well-known member
I think it can be described thus:
- Some people who saw the bird think it was one based on a "positive identification".
- Some people who saw the bird think it was one based on their stance that it couldn't be a Eurasian Curlew (a "negative identification", if you will).
- Some people who saw the bird think it may have been one, but think that views were not quite conclusive or that there are a couple of inconsistencies with it being a S-b C.
- Some people who saw the bird think it definitely wasn't one, based on its appearance.
- Some people who did not see the bird think it was one.
- Some people who did not see the bird think it may have been one, but that there are a couple of inconsistencies with its appearance that mean it should be Not Proven as a first for Britain.
- Some people who did not see the bird think there are enough problems with its appearence to render the identification as S-b C completely unsafe, especially considering that it is also the last record of this species in the World. Ever!
I think its fair to say that most people now fit into points 6 & 7. I must admit, i wish i could put myself into points 1-4, but at the time i was a cash strapped student and was relying on a mate for bird news. Guess what pager company he had
Frenchy
Surely that is no change? Most people have ALWAYS fitted into points 6 & 7 but 'most people' do not have sight of all of the evidence. The only change is the proportion of those individuals that fall into points 6 & 7 who are now present on the respective committees (who may or may not have seen all of the evidence).
All the best
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DMW
Well-known member
I can’t see how the determination of a single bird’s identity by a committee can meaningfully be described as a scientific process. The term “null hypothesis” is generally used where statistical analysis can be performed on a data set, and the probability of the observed outcome being due to random chance can be calculated.
If the null hypothesis is ‘It isn’t one’, on what basis and with what degree of probability are you going to reject the null hypothesis? A head-count of opinions?
I don’t think there’s any need to dress this process-up as anything other than what it is: a group of expert birders using a mix of objective and subjective criteria to reach a reasoned conclusion. Their determination, whatever it is, will not be fact, but opinion.
If the null hypothesis is ‘It isn’t one’, on what basis and with what degree of probability are you going to reject the null hypothesis? A head-count of opinions?
I don’t think there’s any need to dress this process-up as anything other than what it is: a group of expert birders using a mix of objective and subjective criteria to reach a reasoned conclusion. Their determination, whatever it is, will not be fact, but opinion.
Gomphus
Well-known member
I wonder why this record really is so important, if indeed it is the last sighting as has been said, it would actually mean not a jot in the grander scale of things other than it marked the sad passing of a species that went extinct (if it has... My heart still hopes we are wrong) within my life time, in a part of the world that pretends to be conservation aware and should have been quicker off the mark. Or was it that SBC was just a brown spotty Curlew that didn't have a cute spoon bill like another wader we have actually, hopefully, got off our backsides fast enough to save.... but what of Nordmann's Greenshank another species seemingly quietly passing away and I haven't seen such a fuss being made about that as with Spoon billed Sandpiper....... Or am I just becoming too cynical/jaded with it all in my old age
Please please can I request this doesn't go the same way as the other thread... or should they be merged? I have nightmares everytime SBC turns up in a thead title on the first page of this forum!
Steph'
Please please can I request this doesn't go the same way as the other thread... or should they be merged? I have nightmares everytime SBC turns up in a thead title on the first page of this forum!
Steph'
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tittletattler
Well-known member
Except that the feeding action proves that the Hungarian bird is a Eurasian Curlew.
Compare to this footage of Slender-billed Curlews:
http://www.youtube.com/watch?v=tzlQIhWgb3c
Then compare to the typical feeding action of this Eurasian Curlew:
http://www.youtube.com/watch?v=5XagoXUYRNE
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tittletattler
Well-known member
Because to me at least it symbolises a hopefully bygone age of giving the nod to mates birds rather than applying equal, objective analysis to each and every record.
It should serve as a reminder to all those who allow a little bit of authority to go to their heads and how incredibly stupid and arrogant they will look as a result especially now that there is also the added threat of trial by internet.
On the plus side, committees appear to have smartened up their act considerably since.
Cheers, Andy.
ditto Andy happy new year,but we wont have one with these "Tories",and I seen the bird,looked into things,and to my best ability I would take the bird as a SBC,so let me enjoy before tories stop the lot :t:
John Cantelo
Well-known member
Very interesting video footage, Andy. Thanks for posting the details. I've no axe to grind here as I didn't see the bird and had no plans to twitch it. The second video seems to focus on two different birds one of which looks a far better candidate for SBC than the other. Regarding feeding action, doesn't this depend to some degree on environmental conditions and food supply? Whilst I'd expect a bird with a small and delicate bill like SBC to exhibit the more 'picky' action (as per the birds in the first video), I'm not sure that it is necessarily a consistent over a period of time and a range of habitats.
You say that the feeding action proves that the Hungarian bird is a Eurasian Curlew, and then follow that statement with "applying equal, objective analysis to every record". Assuming you have only watched the video of the bird in Hungary, rather than having seen the bird in the field, your two simultaneous posts seem to contradict each other.
Other than the feeding action, what do you base your assertion that the Kiskunsag bird is a Eurasian Curlew?
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Farnboro John
Well-known member
Snore.......
John
John
keith
Well-known member
Sorry Steph, but my original post was just a genuine question about what was happening, if anything, in the proceedure as I'm obviously curious.
Don Draper
Well-known member
Trust me, if you weren't involved at the time, you don't want to know...
Alternatively, there's a link to another BF thread in an earlier post in this thread where you can read all the lovely details. If you have a spare weekend.
