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Index of Subjects ---15486822-233949374-1361191408=:78490 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable =0A=0AAn additional comment on "scoping" waterfowl:=0A=0AThere is a family = of Common Mergansers on the lake (L Torment, East Dalhousie, Kings Co) each= year and I often see them going by on "manouvers". Mother duck puts her he= ad in the water for several seconds and her brood immediately follow suit. = Then she raises her head and shortly all the young raise their heads. This = action is often repeated several times as they swim along the shore. In thi= s case, it would seem that "scoping" is a learned behavior presumably being= taught by the female during feeding lessons. Definitely not a hardwired re= flex like the Diving Response as Ian pointed out.=0A=0AWhy cormorants do no= t scope, however,=A0 remains a mystery.=0A=0A=0ANancy=0A=0A=0A_____________= ___________________=0A From: "iamclar@dal.ca" <iamclar@dal.ca>=0ATo: nature= ns@chebucto.ns.ca =0ASent: Sunday, February 17, 2013 5:53:15 PM=0ASubject: = [NatureNS] Dead murres and "scoping" waterfowl footnote=0A =0AAll:=0A=0APau= l Brodie found a=A0 dead Common Murre floating off Boutlliers Pt., HRM, can= be added to the current toll and coastal span.=0A=0AI thought Nancy Dowd's= suggestion, that "scoping" birds might be initiating the dive reflex very = interesting. But I don't think it covers the prolonged scoping one sees amo= ng some, but not all, divers. The reflex (also occurs in diving mammals, an= d even people to a limited extent), is set very quickly when the face hits = the water.=0A=0AOn the other hand, I don't see (do others?) diving ducks li= ke Athyas and eiders do much if any scoping, yet mergansers do so. The form= er feed on relatively or completey fixed food (weeds & small inverts., muss= els resp.), whereas loons (save the odd crab munchie), alcids and=A0 mergan= sers, are piscivores scoping for location-shifting, active prey.=0A=0ASo th= e question remains, why don't cormorants scope? They can set the dive refle= x readily enough, as Nancy indicates. Am I missing something?=0A=0ACheers, = Ian=0A=0AIan McLaren ---15486822-233949374-1361191408=:78490 Content-Type: text/html; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable <html><body><div style=3D"color:#000; background-color:#fff; font-family:ti= mes new roman, new york, times, serif;font-size:12pt"><div><span><br></span= ></div><div>An additional comment on "scoping" waterfowl:</div><div><br></d= iv><div style=3D"color: rgb(0, 0, 0); font-size: 16px; font-family: times n= ew roman,new york,times,serif; background-color: transparent; font-style: n= ormal;">There is a family of Common Mergansers on the lake (L Torment, East= Dalhousie, Kings Co) each year and I often see them going by on "manouvers= ". Mother duck puts her head in the water for several seconds and her brood= immediately follow suit. Then she raises her head and shortly all the youn= g raise their heads. This action is often repeated several times as they sw= im along the shore. In this case, it would seem that "scoping" is a learned= behavior presumably being taught by the female during feeding lessons. Def= initely not a hardwired reflex like the Diving Response as Ian pointed out.</div><div style=3D"color: rgb(0, 0, 0); font-size: 16px; font-family:= times new roman,new york,times,serif; background-color: transparent; font-= style: normal;"><br></div><div style=3D"color: rgb(0, 0, 0); font-size: 16p= x; font-family: times new roman,new york,times,serif; background-color: tra= nsparent; font-style: normal;">Why cormorants do not scope, however, = remains a mystery.<br></div><div style=3D"color: rgb(0, 0, 0); font-size: 1= 6px; font-family: times new roman,new york,times,serif; background-color: t= ransparent; font-style: normal;"><br></div><div style=3D"color: rgb(0, 0, 0= ); font-size: 16px; font-family: times new roman,new york,times,serif; back= ground-color: transparent; font-style: normal;">Nancy<br></div> <div style= =3D"font-family: times new roman, new york, times, serif; font-size: 12pt;"= > <div style=3D"font-family: times new roman, new york, times, serif; font-= size: 12pt;"> <div dir=3D"ltr"> <font face=3D"Arial" size=3D"2"> <hr size= =3D"1">=20 <b><span style=3D"font-weight:bold;">From:</span></b> "iamclar@dal.ca" <= ;iamclar@dal.ca><br> <b><span style=3D"font-weight: bold;">To:</span></b= > naturens@chebucto.ns.ca <br> <b><span style=3D"font-weight: bold;">Sent:<= /span></b> Sunday, February 17, 2013 5:53:15 PM<br> <b><span style=3D"font-= weight: bold;">Subject:</span></b> [NatureNS] Dead murres and "scoping" wat= erfowl footnote<br> </font> </div> <br>All:<br><br>Paul Brodie found a = ; dead Common Murre floating off Boutlliers Pt., HRM, can be added to the c= urrent toll and coastal span.<br><br>I thought Nancy Dowd's suggestion, tha= t "scoping" birds might be initiating the dive reflex very interesting. But= I don't think it covers the prolonged scoping one sees among some, but not= all, divers. The reflex (also occurs in diving mammals, and even people to= a limited extent), is set very quickly when the face hits the water.<br><b= r>On the other hand, I don't see (do others?) diving ducks like Athyas and eiders do much if any scoping, yet mergansers do so. The former feed on re= latively or completey fixed food (weeds & small inverts., mussels resp.= ), whereas loons (save the odd crab munchie), alcids and mergansers, = are piscivores scoping for location-shifting, active prey.<br><br>So the qu= estion remains, why don't cormorants scope? They can set the dive reflex re= adily enough, as Nancy indicates. Am I missing something?<br><br>Cheers, Ia= n<br><br>Ian McLaren<br><br><br><br> </div> </div> </div></body></html> ---15486822-233949374-1361191408=:78490--
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