Roger Hebb wrote:
i think Alex lees if you study Blacktoft sands records when Andrew greave was there their is reports of Goshawks in mainly march and october which suggests they entrered lincs!!!i have these reports.
Alex there is nothing more i want than you to see a gosey in lincs,to overcome your predilictions of fiqure and facts which at the end of the day prove nothing,as the black kite records clearly show in the last few years you and gpc were wrong on the status of black kites as you both are on goshawks.
Roger Hebb.
Hi Roger!
Good to have you in the fold. I think we ought to stick to
Accipiter rather than involve
Milvus in this, but, while we're here....
I don't seem to remember being wrong about the status of BK, apologies for my
'predilictions of fiqure and facts' over heresay and speculation. Graham did score a little own goal over the Barton bird but this only served to show how hard BKs can be to identify. Moreover this bird's diagnostic primary damage facilitated its tracking all across eastern England, and dispelled thoughts of multiple birds residing in North Norfolk - if it wasn't for this then the totals would have been wrongly inflated. Cast your mind back to this graph on the status of BKs
http://www.lincsbirds.co.uk/album/displ ... ?pos=-5450 this is irrefutable evidence, I'd suggest you reconsider your apparently immutable postion on this one and steer clear of logical fallacies.
Anyway back to Goshawks.
I've asked two questions. It still strikes me as odd that no-one has managed to take a picture of a Goshawk in the county - is there any other species (apart from some pelagic stuff) of an even vaguely comparable status that has not been photographed in this time-scale? Goshawks should occur in Lincs - as has been pointed out they breed as close as the Dukeries and in Yorks (status occluded by misidentification in both areas though). One would expect records on the coast to fall in March-April and Oct-Nov when small numbers of Continental birds occur, presumably British dispersers should occur in late summer-autumn. Moreover, the UK dispersers should be juveniles which are easier to identify than adults. Really, we should only expect juveniles until one or more birds set up territory. Once this happens then Goshawk will become easy. If its on territory then its showing on 70% of days between late Jan-April. Easy. So how come the reports are always adults? Goshawk territories in prey-rich lowland Britain are small - typically less than 10 square kilometres. Adults will not be visiting Lincs to hunt unless they breed here. They don't breed here because otherwise we would see them, they would end up killing crows in people's gardens like this one:
http://www.jackiefreemanphotography.com/goshawk.htm . Note this is a hyper-diagnostic juv, or hunting the gulls on tips - something they do a lot both here and broad cf: this one
http://www.lintukuva.fi/lajikuvat/accge ... en306i.jpg and this one:
http://www.tarsiger.com/gallery/index.p ... 4&lang=eng also check out the video of this one- I'm waiting for Roy to better it:
http://www.nrk.no/nyheter/distrikt/osta ... /1.6328371Lincs has one of the lowest birder densities in England, south Lincs in particular is massively underwatched. In the main, Goshawk records don't come from south Lincs however (which has the most extensive areas of suitable habitat). This argument may become tautological but I certainly don't see how you can hide Goshawks anywhere in the north of the county. Enough birders to find them and no extensive areas of woodland from them to hide away in. They don't move around much, otherwise we would get records in Norfolk away from breeding sites (there are several well-known pairs in Breckland and in West Norfolk), they just seem to exhibit a high degree of natal philopatry. Although you state Roger that you have only a handful of personal sightings, you did formerly argue that Goshawks were permanently present in the county. I guess you consider this position untenable now? This still leaves us with the bizarre nature of the demographic structure of records, which strikes me as weird.....
Alex
_________________
Dr Alexander C. Lees
Lecturer in tropical ecologyManchester Metropolitan University
Lab Associate
Cornell Lab of Ornithology,
Cornell University
http://www.freewebs.com/alexlees/index.htm@Alexander_Lees