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>> I was on the lower part of the drumlin in the Mt Uniacke Hou Last night, I did find a couple of references to Bt killing of non-target insects, and Leps in particular. I've also been in touch with an entomologist friend in Chicago whose work deals with restoration projects for species at risk Leps. He feels that these kinds of spray programs do present a danger to non-target species and has some references which he'll be sending along when he returns to work early next week. Does anyone know when there has been spraying in the past? Who is keeping track of where and when the spraying is done? That would be a good question to begin with. If no one has been bothering to sample insect populations ahead of spraying, and again after, and if they aren't really keeping track of when and where spraying was done, that's not particularly responsible. I'd like to think that someone is actually caring enough about the insect diversity of the province to want to avoid killing moths like Cecropia, Luna, Polyphemus, various Sphinx, and the many other moths and all the butterflies that are part of the ecological web. And, as I read in one of the references last night, some species of insectivores actually *benefit* from spikes in some of the most despised forest insects -- and that can actually take care of a population spike in a target species while boosting those insectivore populations. That's just the kind of thing we should be studying rather than jumping the gun on widespread spraying. Just for the record. I have been photographing moths at Round Hill for 7 summers now. This has been a very disappointing summer for moths at the lamps. Barely any Sphinx, only one Cecropia and a couple of Luna. I've had a lot of the smaller moths including a few new species, but many of the "regulars" have either been absent or only in small numbers. All in all, a real wash-out of a season. It would be interesting to know what is going on. Not long ago, I read an article on biologists in Europe realizing that they need to be setting up insect monitoring stations as they have a very poor base-line from which to figure out what species should occur and where, and whether numbers are dropping. I strongly suspect that we aren't doing much if any better than the Europeans when it comes to monitoring. Bev Wigney Round Hill, NS On 8/27/16, Stephen Shaw <srshaw@dal.ca> wrote: > Donna’ original comment was about possible ‘bycatch’ effects on other > butterflies, of widespread spraying with Bt (Bacillus thuringiensis) > anti-insect preparations against budworm. > > I had a look for this on Google under ‘bt spruce budworm’ for about 10 > pages, and didn’t see any title that stood out as having examined this > critically. Maybe it’s there somewhere but would take work to uncover it. > Most of the articles seemed to be government- or forest industry-sourced and > 'good-thing positive’. > The Wikipedia entry under Bt is extensive but again is positive with little > negative regarding side effects, as if written by forest industry > apologists. According to that source, Bt preparations besides being toxic > to Lepidoptera also go for Diptera, flies, Hymenoptera, bees etc, and > Coleoptera, beetles: as these are the largest insect groups species- and > biomass-wise, it therefore would account for a large fraction of all > insects. Presumably any larva or adult in these groups in that habitat that > ingests recently sprayed leaves or needles is likely to suffer a similar > percentage mortality as the spruce budworm larvae. > > Beyond the approach of spraying Bt, there has been controversy over a study > that found monarch butterflies could suffer Bt poisoning from nearby maize > plants genetically engineered to express Bt genes. This seems to have been > refuted by later work claiming that the level of Bt toxins from maize > encountered by such monarchs would be too low to affect them adversely. > > I would have liked to have a read a more critical evaluation of > insect-bycatch from a credible source but didn’t find anything so far. > Maybe others here have found better information? > Steve (Hfx) > > > Aug 27, 2016, at 5:44 PM, Rick Whitman <dendroica.caerulescens@gmail.com> > wrote: >> Indeed ! I have been thinking this for several years now. Surely many of >> us can remember those windshields. It can't be all better air flow / >> design ? >> >> A phone message, may be brief! >> Rick >> >> >> On Aug 27, 2016, at 10:08 AM, Eleanor Lindsay <kelindsay135@gmail.com> >> wrote: >> >> For the past 30+ years I have made regular summer car trips from St >> Margarets Bay to Fredericton; in the early days I used to frequently have >> to stop to clear accumulations of dead insects from my front windshield. I >> am no longer sure about the exact time frame of this change, but yesterday >> on return home I was struck by the total lack - not one single insect on >> my windshield, which speaks such volumes about the enormity of change >> happening around us - and also how easy it can be not to be so quick to >> notice or object to the 'convenient' changes................... >> >> Eleanor Lindsay >> >> >>> On 2016-08-26 9:17 PM, Donna Crossland wrote: >>> It's very interesting to read of these various insect observations. >>> Creating awareness is valuable to those of us who haven't yet ventured >>> into >>> this domain. >>> >>> >>> I could use some help from folks who are much more in-the-know on what >>> they >>> might predict the potential effects of spraying bT for spruce budworm >>> would >>> do to our butterfly populations and other insects. It's all potential >>> bird >>> food in my mind, and that's a concern, but what of other non-target >>> insect >>> populations here? Timing is everything, as I understand it. I haven't >>> had >>> time to research this topic, but I would like some Nova Scotia-specific >>> observations/predictions on what that might mean to our insect >>> populations >>> if spraying began next year, which may happen. Thoughts? >>> >>> >>> Donna Crossland (naive insect person) >>> >>> >>> From: naturens-owner@chebucto.ns.ca >>> [mailto:naturens-owner@chebucto.ns.ca] >>> On Behalf Of Mary Macaulay >>> Sent: August-26-16 9:09 AM >>> To: naturens@chebucto.ns.ca >>> Subject: Re: [NatureNS] Butterfly numbers >>> >>> >>> Sadly this is a global phenomenon. We are now very sophisticated wit