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Oberhauser [reference 1] of some curren This is a multi-part message in MIME format. --------------F8B79671F7D245E8FF2B6CC9 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Hi Nancy & All, Absolute truth. D W, Kentville. On 10/20/2019 6:42 AM, nancy dowd wrote: > Lots to consider here. Habitat protection/enhancement is always key > to species survival. > > NancyD > > Sent from my iPad > > On Oct 19, 2019, at 10:57 PM, Stephen Shaw <srshaw@dal.ca > <mailto:srshaw@dal.ca>> wrote: > >> I noticed the announcement below just after reading a recent review >> by Karen Oberhauser [reference 1] of some current research by others >> [ref 2] on monarch 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 by schools and others, with educational benefits for >> students, but with unexpected deleterious consequences. Specimens of >> this origin are genetically far removed from other known wild >> migratory populations, and don’t migrate. That is, when tested in a >> "flight simulator”, 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, wild-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’t get back to Mexico to overwinter. >> This practice of captive-breeding and release is even argued to >> possibly damage the real wild migratory populations by dilutional >> breeding-in of non-migratory genes [ref 1], though I couldn’t 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 >> caterpillars: wild larvae “rescued” and then reared in captivity >> indoors also lost their ability to orient south in the fall, under >> the two breeding regimes tested in [2]. The reason offered is that >> two triggers normally cooperate to eventually release the innate >> ability to orient south: gradually declining autumnal day-length, >> and substantial day-night temperature fluctuation. Neither of these >> triggers will be reproduced if wild larvae are collected then reared >> in fairly constant conditions indoors, for future release in October. >> Only wild-rescued monarch larvae /reared outdoors/ allowed them to >> develop and express their innate migratory ability in the Fall. >> Taking wild larvae indoors to protect and breed them through in >> relatively constant conditions and then release them is not only >> useless but actually harmful to population success overall. It >> ensures that while they fly away blissfully when released, none will >> migrate directionally, whereas most would have headed south with some >> percentage success if they had been left to pupate outdoors, >> undisturbed. Failure of any of these monarchs to arrive obviously >> will reduce 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 with. Oberhauser suggests that focussing on protecting >> existing and creating new appropriate habitat will be the most >> helpful way to support future healthy monarch populations. >> >> [1] Oberhauser, K. (26 Sept 2019). Captivity concerns for monarch >> butterflies. Nature 573: 501-2. (Be aware of some bizarre syntax >> though — for instance, the triple negative in her very last sentence >> in fact contradicts the substance of the review). >> >> [2] Tenger-Trolander, A., Lu, W., Noyes, M., & Kronforst, M.R. (2019) >> Contemporary loss of migration in monarch butterflies. Proc. Natl. >> Acad. Sci. USA 116: 14671-6. >> >> Steve (Hfx) >> --------------------------------------------------------------- >> On Oct 18, 2019, at 9:40 PM, Soren Bondrup-Nielsen <soren@bondrup.com >> <mailto:soren@bondrup.com>> wrote: >> >>> Please see below. It’s 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:valleyflyingsquirrels@gmail.com>> >>>> >>>> Hi everyone, >>>> <image.png>things are lining up for a sweet gathering at the Ravine >>>> tomorrow (Sat, Oct 19th). We've got another fun nature challenge >>>> suited to all ages, live music with Heather Kelday, hot cider and >>>> popcorn and *a Monarch send-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 the 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 old in the heart of the Valley. >>>> >>> _______________________________________________ >>> BNS mailing list >>> BNS@nature1st.net <mailto:BNS@nature1st.net> >>> http://nature1st.