Enjoyed a super talk last night well presented by Richard Broughton and ending with some interesting questions from OOS members. Richard threw up some real surprises about his well researched subject The Marsh Tit, not least the huge territories they seem to need, and while not blaming the Sparrowhawk he is prepared to throw predation by them into the mix. Personally I believe that both these birds evolved together and pre-DDT eggshell weakening I know of no reference being made of Sparrowhawk being a significant destroyer of Marsh Tit and of course a rise of Sparrowhawk numbers by a factor of some 150% merely brings them up to their pre-DDT levels, but like Richard I will keep an open mind until such time as more light can be thrown on things. It was good to meet members including fellow blogger the Gnome although his mate the Badger failed to stir himself into action, perhaps he is becoming too "sett" in his ways, i'm not serious Badge I know if you could have made it you would have done.
No chance of birding today as the Tree Sparrow Project had a Millet delivery at Alan Larkmans place which entails Alan and I carting forty bags from the drop off point some fifty yards to the storage point. Also picked up my Mother and Brother-in-Law as I usually do on a Thursday in order to get her out of the old folks home for a few hours to give her a break, she really appreciates the ride round and we spent a restful couple of hours at my place (Pinfold) in Bampton. Writing Xmas cards tomorrow but hoping to get birding at some time during the day, in fact another look at the Falcated is a strong possibility.
Linnets at Alans-about 100 plus today
The Redwing seem to be more dispersed.
So do the Fieldfare
And oh so many Pheasants in the countryside
camboy
Linnets at Alans-about 100 plus today
The Redwing seem to be more dispersed.
So do the Fieldfare
And oh so many Pheasants in the countryside
Cheers for the good review! The difference pre-DDT was that there were not so many Blue Tits, and there were more hedgerows connecting the woods, so in these ways it was a different world if you were a Marsh Tit (you had the woods more to yourself, and could move between them more easily). We also don't know if spars are back to pre-DDT levels, or actually higher (records only start in 1975, before DDT kicked in). The idea is that the three things (Spars, Blues and hedges) might be ok on their own, but combined they could amplify each others effect. More work's needed, but there are precedents for the predation hypothesis - the work on Grey Partridge shows that once numbers get very low then one of the main factors finishing them off is...Sparrowhawks. It's a tough old world!
ReplyDeleteOoops, that should be 1975 AFTER DDT kicked in!
DeleteHi Richard, I would very much appreciate the paper on the Grey Partridge (hope its not one of those put up jobs by the shooting fraternity) My recollection of the demise of the English or Grey Partridge is the wholesale ploughing up of pastureland that traditionally harboured the ant eggs & grubs that the chicks thrived on-yes I go back that far and of course English Partridge is a misnomer due the near wiping out of them by over shooting and the importing of Hungarian etc to artificially boost shootable numbers. As a young fella late fifties I was a keen shooting devotee and a supporter of the then fledling Game Conservancy over the years it gradually became clearer that they were unwittingly becoming a force for imbalance in the countryside to the extent where a guilty shooters conscience refered to "the numbers game" in recognition of having gone too far with other species destruction and importation of massive amounts of Pheasant and Partridge having a very detrimental effect on other farmland birds.
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