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--_000_3C4C4F3A78A644BF86B4E8A9641D1B42dalca_ Content-Type: text/plain; charset="Windows-1252" Content-Transfer-Encoding: quoted-printable I noticed the announcement below just after reading a recent review by Kare= n 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= worth a comment here. 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 unex= pected deleterious consequences. Specimens of this origin are genetically = far removed from other known wild migratory populations, and don=92t migrat= e. That is, when tested in a "flight simulator=94, monarchs bred from such= sources did not show any directional migratory flight either in summer, or= more relevantly in October when migration normally starts. By contrast, w= ild-caught, wild-reared individuals from the east do orient in October as = if to head south, as expected. The commercial monarchs apparently fly off = in all directions so won=92t get back to Mexico to overwinter. This pract= ice of captive-breeding and release is even argued to possibly damage the r= eal wild migratory populations by dilutional breeding-in of non-migratory g= enes [ref 1], though I couldn=92t see the logic of this if none of the faux= specimens ever actually reach Mexico. Even worse, and relevant to collection and protection of wild local caterpi= llars: wild larvae =93rescued=94 and then reared in captivity indoors also= lost their ability to orient south in the fall, under the two breeding reg= imes tested in [2]. The reason offered is that two triggers normally coope= rate to eventually release the innate ability to orient south: gradually d= eclining autumnal day-length, and substantial day-night temperature fluctua= tion. Neither of these triggers will be reproduced if wild larvae are coll= ected then reared in fairly constant conditions indoors, for future release= in October. Only wild-rescued monarch larvae reared outdoors allowed them to develop an= d express their innate migratory ability in the Fall. Taking wild larvae i= ndoors to protect and breed them through in relatively constant conditions = and then release them is not only useless but actually harmful to populatio= n success overall. It ensures that while they fly away blissfully when rel= eased, none will migrate directionally, whereas most would have headed sout= h with some percentage success if they had been left to pupate outdoors, un= disturbed. Failure of any of these monarchs to arrive obviously will reduc= e the already-challenged overwintering Mexican population. The road to hell is paved with good intentions, perhaps. Migratory ability is fragile and can disappear quite easily if interfered w= ith. Oberhauser suggests that focussing on protecting existing and creatin= g new appropriate habitat will be the most helpful way to support future he= althy monarch populations. [1] Oberhauser, K. (26 Sept 2019). Captivity concerns for monarch butterfli= es. Nature 573: 501-2. (Be aware of some bizarre syntax though =97 for in= stance, the triple negative in her very last sentence in fact contradicts t= he substance of the review). [2] Tenger-Trolander, A., Lu, W., Noyes, M., & Kronforst, M.R. (2019) Conte= mporary loss of migration in monarch butterflies. Proc. Natl. Acad. Sci. U= SA 116: 14671-6. Steve (Hfx) --------------------------------------------------------------- On Oct 18, 2019, at 9:40 PM, Soren Bondrup-Nielsen <soren@bondrup.com<mailt= o:soren@bondrup.com>> wrote: Please see below. It=92s worth attending. Soren Begin forwarded message: From: Judy Lipp <judylipp@gmail.com<mailto: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<mailto:vall= eyflyingsquirrels@gmail.com>> Hi everyone, <image.png>things are lining up for a sweet gathering at the Ravine tomorro= w (Sat, Oct 19th). We've got another fun nature challenge suited to all ag= es, live music with Heather Kelday, hot cider and popcorn and a Monarch sen= d-off ceremony + some give aways. 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 And if you can't make it, our next outing is on Saturday November 16th in t= he Ravine. Wishing all a lovely weekend Judy -- Judy Lipp Program Coordinator Flying Squirrel Adventures https://valleyflyingsquirrel.wordpress.com/ Flying Squirrel Adventures is a free outdoor nature program for young and o= ld in the heart of the Valley. _______________________________________________ BNS mailing list BNS@nature1st.net<mailto:BNS@nature1st.net> http://nature1st.net/mailman/listinfo/bns_nature1st.net --_000_3C4C4F3A78A644BF86B4E8A9641D1B42dalca_ Content-Type: text/html; charset="Windows-1252" Content-ID: <881625F82DA15B4E81BB6FF889B80661@CANPRD01.PROD.OUTLOOK.COM> Content-Transfer-Encoding: quoted-printable <html> <head> <meta http-equiv=3D"Content-Type" content=3D"text/html; charset=3DWindows-1= 252"> </head> <body style=3D"word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-lin= e-break: after-white-space;"> I noticed the announcement below just after reading a recent review by Kare= n 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 worth a comment here. <div> <div>Early stages of monarchs can be purchased to be bred through and relea= sed by schools and others, with educational benefits for students, but with= unexpected deleterious consequences. Specimens of this origin are ge= netically far removed from other known wild migratory populations, and don=92t migrate. That is, when teste= d in a "flight simulator=94, monarchs bred from such sources did not s= how any directional migratory flight either in summer, or more relevantly i= n October when migration normally starts. By contrast, wild-caught, <i>wild-reared</i> &n