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contrast, wild-caught, <i>wild-reared</i>&nbsp;&n --Apple-Mail-C4487CD4-7C0D-41FF-9754-57F63F4C0B57 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Lots to consider here. Habitat protection/enhancement is always key to spec= ies survival. NancyD Sent from my iPad > On Oct 19, 2019, at 10:57 PM, Stephen Shaw <srshaw@dal.ca> wrote: >=20 > I noticed the announcement below just after reading a recent review by Kar= en Oberhauser [reference 1] of some current research by others [ref 2] on mo= narch migration. The topic has been discussed before on NatureNS and seems w= orth a comment here.=20 > =20 > Early stages of monarchs can be purchased to be bred through and released b= y schools and others, with educational benefits for students, but with unexp= ected deleterious consequences. Specimens of this origin are genetically fa= r removed from other known wild migratory populations, and don=E2=80=99t mig= rate. That is, when tested in a "flight simulator=E2=80=9D, monarchs bred f= rom such sources did not show any directional migratory flight either in sum= mer, or more relevantly in October when migration normally starts. By contr= ast, wild-caught, wild-reared individuals from the east do orient in Octobe= r as if to head south, as expected. The commercial monarchs apparently fly o= ff in all directions so won=E2=80=99t get back to Mexico to overwinter. Th= is practice of captive-breeding and release is even argued to possibly damag= e the real wild migratory populations by dilutional breeding-in of non-migra= tory genes [ref 1], though I couldn=E2=80=99t see the logic of this if none o= f the faux specimens ever actually reach Mexico. =20 >=20 > Even worse, and relevant to collection and protection of wild local caterp= illars: wild larvae =E2=80=9Crescued=E2=80=9D and then reared in captivity i= ndoors also lost their ability to orient south in the fall, under the two br= eeding regimes tested in [2]. The reason offered is that two triggers norm= ally cooperate to eventually release the innate ability to orient south: gr= adually declining autumnal day-length, and substantial day-night temperature= fluctuation. Neither of these triggers will be reproduced if wild larvae a= re collected then reared in fairly constant conditions indoors, for future r= elease in October. > =20 > Only wild-rescued monarch larvae reared outdoors allowed them to develop a= nd express their innate migratory ability in the Fall. Taking wild larvae i= ndoors to protect and breed them through in relatively constant conditions a= nd then release them is not only useless but actually harmful to population s= uccess overall. It ensures that while they fly away blissfully when release= d, none will migrate directionally, whereas most would have headed south wit= h some percentage success if they had been left to pupate outdoors, undistur= bed. Failure of any of these monarchs to arrive obviously will reduce the a= lready-challenged overwintering Mexican population. =20 >=20 > The road to hell is paved with good intentions, perhaps.=20 >=20 > Migratory ability is fragile and can disappear quite easily if interfered w= ith. Oberhauser suggests that focussing on protecting existing and creating= new appropriate habitat will be the most helpful way to support future heal= thy monarch populations. >=20 > [1] Oberhauser, K. (26 Sept 2019). Captivity concerns for monarch butterfl= ies. Nature 573: 501-2. (Be aware of some bizarre syntax though =E2=80=94 f= or instance, the triple negative in her very last sentence in fact contradic= ts the substance of the review). >=20 > [2] Tenger-Trolander, A., Lu, W., Noyes, M., & Kronforst, M.R. (2019) Cont= emporary loss of migration in monarch butterflies. Proc. Natl. Acad. Sci. U= SA 116: 14671-6. >=20 > Steve (Hfx) > --------------------------------------------------------------- > On Oct 18, 2019, at 9:40 PM, Soren Bondrup-Nielsen <soren@bondrup.com> wro= te: >=20 >> Please see below. It=E2=80=99s worth attending. >> Soren >>=20 >>> Begin forwarded message: >>> From: Judy Lipp <judylipp@gmail.com> >>> Subject: FSA party is on for Sat Oct 19th - come send off the Monarchs >>> Date: October 18, 2019 at 9:22:47 PM ADT >>> To: Flying Squirrel Adventures <valleyflyingsquirrels@gmail.com> >>>=20 >>> Hi everyone,=20 >>> <image.png>things are lining up for a sweet gathering at the Ravine tomo= rrow (Sat, Oct 19th). We've got another fun nature challenge suited to all a= ges, live music with Heather Kelday, hot cider and popcorn and a Monarch sen= d-off ceremony + some give aways.=20 >>>=20 >>> We hope you'll join us for some or all of the festivities >>> Meet at the upper parking lot, Kentville Ravine, 10 am - 12:30 pm >>>=20 >>> And if you can't make it, our next outing is on Saturday November 16th i= n the Ravine. =20 >>>=20 >>> Wishing all a lovely weekend >>> Judy >>>=20 >>> --=20 >>> Judy Lipp >>> Program Coordinator >>> Flying Squirrel Adventures >>> https://valleyflyingsquirrel.wordpress.com/ >>>=20 >>> Flying Squirrel Adventures is a free outdoor nature program for young an= d old in the heart of the Valley. >>>=20 >> _______________________________________________ >> BNS mailing list >> BNS@nature1st.net >> http://nature1st.net/mailman/listinfo/bns_nature1st.net >=20 --Apple-Mail-C4487CD4-7C0D-41FF-9754-57F63F4C0B57 Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: quoted-printable <html><head><meta http-equiv=3D"content-type" content=3D"text/html; charset=3D= utf-8"></head><body dir=3D"auto">Lots to consider here. Habitat protec= tion/enhancement is always key to species survival.<div><br></div><div>Nancy= D<br><br><div id=3D"AppleMailSignature" dir=3D"ltr">Sent from my iPad</div><= div dir=3D"ltr"><br>On Oct 19, 2019, at 10:57 PM, Stephen Shaw <<a href=3D= "mailto:srshaw@dal.ca">srshaw@dal.ca</a>> wrote:<br><br></div><blockquote= type=3D"cite"><div dir=3D"ltr"> <meta http-equiv=3D"Content-Type" content=3D"text/html; charset=3DWindows-12= 52"> I noticed the announcement below just after reading a recent review by Karen= Oberhauser [reference 1] of some curren