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Index of Subjects
Index of Subjects --0016e6db5c387adb370467a06e6c Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: quoted-printable I knew if I posted it here, if it were off the wall someone would comment. Thank you Paul! Hope you post your comments at the source. --ST On Wed, Apr 15, 2009 at 8:01 PM, Paul S. Boyer <psboyer@eastlink.ca> wrote: > This is a good example of GW hysteria by the mainstream media, in this ca= se > by the highly unreliable Reuters. The article is pure speculation. It a= lso > ignores the fact that the Earth was warmer just 7,000 years ago, and cold= er > during the Little Ice Age, and warblers seem to have made it through thos= e > changes just fine. > The principle problem for birds migrating between Europe and Africa, like > those described in the article, is loss of habitat (particularly in Afric= a). > It is also generally true that the bigger the bird, the more likely it i= s > to be pestered by humans: chased, shot, eaten, &c. > > The conversion of temperature into an equivalent surface distance needed > for migration assumes that temperature is the main control of bird > migration, which almost everyone who has studied the subject knows is jus= t > not true. Food is the main motive for migration, and the food needs vary > according to species. Birds will put up with a wide range of temperature= s, > if the food is available. That is the reason so many feeder-species have > moved north, and now stay longer in the winter: if the food is adequate, > they will stay. It is one of the amazing things we observe: tiny little > creatures, out in the cold, with nothing but a thin layer of puffed-out > feathers to separate them from freezing =97 and yet they can handle this,= if > they have enough food. They certainly can tolerate temperature extremes > much better than unprotected humans. > > Canada Geese have largely given up migration entirely, because they find = it > easier to graze on man-made lawns than to make an arduous migration fligh= t. > This certainly does not indicate that the seasons have ceased to occur. > > I have not been able to find a single convincing case of a migration > problem which would be caused by a change in a fraction of a degree. > Indeed, the severity of winters from year to years varies by much more t= han > that. > > There is much we do not understand about bird migration. There is also > much we have to discover about changes in bird population. Our lack of > complete knowledge is no reason for us uncritically to believe every > tendentious news story which comes along. > > > On 15 Apr 2009, at 2:03 PM, Suzanne Townsend wrote: > > > http://www.reuters.com/article/environmentNews/idUSTRE53D7G220090415?feed= Type=3DRSS&feedName=3DenvironmentNews > > > --0016e6db5c387adb370467a06e6c Content-Type: text/html; charset=windows-1252 Content-Transfer-Encoding: quoted-printable <div>I knew if I posted it here, if it were off the wall someone would comm= ent. Thank you Paul! Hope you post your comments at the source.</div> <div>--ST<br><br></div> <div class=3D"gmail_quote">On Wed, Apr 15, 2009 at 8:01 PM, Paul S. Boyer <= span dir=3D"ltr"><<a href=3D"mailto:psboyer@eastlink.ca">psboyer@eastlin= k.ca</a>></span> wrote:<br> <blockquote class=3D"gmail_quote" style=3D"PADDING-LEFT: 1ex; MARGIN: 0px 0= px 0px 0.8ex; BORDER-LEFT: #ccc 1px solid"> <div style=3D"WORD-WRAP: break-word">This is a good example of GW hysteria = by the mainstream media, in this case by the highly unreliable Reuters. =A0= The article is pure speculation. =A0It also ignores the fact that the Earth= was warmer just 7,000 years ago, and colder during the Little Ice Age, and= warblers seem to have made it through those changes just fine.=20 <div><br></div> <div>The principle problem for birds migrating between Europe and Africa, l= ike those described in the article, is loss of habitat (particularly in Afr= ica). =A0It is also generally true that the bigger the bird, the more likel= y it is to be pestered by humans: chased, shot, eaten, &c.</div> <div><br></div> <div>The conversion of temperature into an equivalent surface distance need= ed for migration assumes that temperature is the main control of bird migra= tion, which almost everyone who has studied the subject knows is just not t= rue. =A0Food is the main motive for migration, and the food needs vary acco= rding to species. =A0Birds will put up with a wide range of temperatures, i= f the food is available. =A0That is the reason so many feeder-species have = moved north, and now stay longer in the winter: if the food is adequate, th= ey will stay. =A0It is one of the amazing things we observe: tiny little cr= eatures, out in the cold, with nothing but a thin layer of puffed-out feath= ers to separate them from freezing =97 and yet they can handle this, if the= y have enough food. =A0They certainly can tolerate temperature extremes muc= h better than unprotected humans.</div> <div><br></div> <div>Canada Geese have largely given up migration entirely, because they fi= nd it easier to graze on man-made lawns than to make an arduous migration f= light. =A0This certainly does not indicate that the seasons have ceased to = occur.</div> <div><br></div> <div>I have not been able to find a single convincing case of a migration p= roblem which would be caused by a change in a fraction of a degree. =A0Inde= ed, the severity of winters from year to years varies by much more than tha= t.</div> <div><br></div> <div>There is much we do not understand about bird migration. =A0There is a= lso much we have to discover about changes in bird population. =A0Our lack = of complete knowledge is no reason for us uncritically to believe every ten= dentious news story which comes along.</div> <div class=3D"im"> <div><br></div> <div><br> <div> <div>On 15 Apr 2009, at 2:03 PM, Suzanne Townsend wrote:</div><br> <blockquote type=3D"cite"><a href=3D"http://www.reuters.com/article/environ= mentNews/idUSTRE53D7G220090415?feedType=3DRSS&feedName=3DenvironmentNew= s" target=3D"_blank">http://www.reuters.com/article/environmentNews/idUSTRE= 53D7G220090415?feedType=3DRSS&feedName=3DenvironmentNews</a></blockquot= e> </div><br></div></div></div></blockquote></div><br> --0016e6db5c387adb370467a06e6c--