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> Even where buffers are left as per le On 6/23/2016 9:10 PM, Stephen Shaw wrote: > As you know, there's a different group commonly called 'blackfly', including the blackbean aphid, Aphis fabae, a pest of runner beans and some flowers, known to gardeners. Aphids commonly do have a prominent asexually-reproducing part of their life cycle that allows for rapid multiplication and colonization. In regard to an asexuality/ parthenogenesis lifestyle, my initial guess was that you could be remembering this plant-sucking aphid type of blackfly, not human-biting dipteran blackflies. * no I was remembering a professor at U of T when I was a grad student in the 1970s who had a labfull of students working on karyotypes and ploidies of Simuliidae - but I never knew the details, and they just didn't come up in a simple google, so I seem to have misremembered the asexual part. fred. =================================================== > There are a large number of species of 'blackfly', Simuliidae, a family in the primitive branch of two-winged flies, Diptera -- the Nematocera or 'longhorns', referring to their long antennae, the group in question here. I don't recall ever hearing that any of these reproduce asexually, so checked the Manual of Nearctic Diptera vol 1. This indicates that sexual reproduction is the norm, but mentions the unusual Scandanavian case of the Prosimulium ursinum. There, a female sometimes fails to emerge from the pupa, dies in place and disintegrates whereupon matured eggs wash out into the stream, overwinter, and emerge parthenogenetically next spring. > > So you can never be too careful when making generalizations, where exceptions to the rule may be lurking. > Steve (Hfx) > ________________________________________ > From: naturens-owner@chebucto.ns.ca [naturens-owner@chebucto.ns.ca] on behalf of Fred Schueler [bckcdb@istar.ca] > Sent: Thursday, June 23, 2016 5:07 PM > To: naturens@chebucto.ns.ca > Subject: Re: [NatureNS] absence of insects > > On 6/23/2016 3:43 PM, Donna Crossland wrote: >> Darn! Ha, ha, I’ve heard the song played on CBC but never saw the >> video. It’s true the black flies seem larger in northern Ontario. I >> think a different species from here. > > * there are hundreds of species and, I seem to recall, asexual lineages > with diverse karyotypes - https://en.wikipedia.org/wiki/Simulium - some > feed on one species of host or another, and some don't take a blood meal. > > fred. > ===================================================== >> >> >> >> I seem to be too late with thoughts on the black fly. Annapolis Royal >> has claimed a ‘_black fly_ _festival’_, though I’ve never seen a black >> fly there, and they’d be nothing compared to the wooded heartlands of >> NS. A ‘_black fly_ _supper’_ probably wouldn’t draw a big crowd.... : ) >> >> >> >> Donna >> >> >> >> *From:*naturens-owner@chebucto.ns.ca >> [mailto:naturens-owner@chebucto.ns.ca] *On Behalf Of *Rick Whitman >> *Sent:* June-23-16 4:01 PM >> *To:* naturens >> *Subject:* Re: [NatureNS] absence of insects >> >> >> >> We can't claim it, Donna. Ontario already has it: >> >> >> >> https://www.youtube.com/watch?v=qjLBXb1kgMo >> >> >> >> Rick Whitman >> >> >> >> On 23 June 2016 at 15:00, Donna Crossland <dcrossland@eastlink.ca >> <mailto:dcrossland@eastlink.ca>> wrote: >> >> Thanks, John, for offering the thought of blackflies being keystone >> species. Being a non-aquatic person, I hadn’t thought of their >> filtering abilities and incorporating organic matter. Do you think >> we’d get very far offering the black fly as a new and official >> provincial insect of our wonderful province? Ha, ha. >> >> >> >> Donna >> >> >> >> *From:*naturens-owner@chebucto.ns.ca >> <mailto:naturens-owner@chebucto.ns.ca> >> [mailto:naturens-owner@chebucto.ns.ca >> <mailto:naturens-owner@chebucto.ns.ca>] *On Behalf Of *John Kearney >> *Sent:* June-23-16 8:25 AM >> *To:* naturens@chebucto.ns.ca <mailto:naturens@chebucto.ns.ca> >> *Subject:* RE: [NatureNS] absence of insects >> >> >> >> As always Donna, you have given an excellent explanation of the possible >> effects of forestry on Black Fly populations. In addition to the lack of >> food for birds resulting from fewer flies, the Black Fly larvae are an >> important food source for fish and the larvae of larger aquatic insects >> such as mayflies and damselflies. As filter feeders, the Black Fly >> larvae play a crucial role in incorporating organic matter into the >> aquatic food chain. As filter feeders, they could also serve as >> indicator species for aquatic pollution, and in Nova Scotia especially, >> for mercury pollution. The adult male Black Fly, which feeds on nectar, >> may even play some role in pollination. Here we have a species that is >> crucial to both aquatic and terrestrial ecosystems. Certainly the Black >> Fly is a keystone forest species. >> >> John >> >> >> >> *From:*naturens-owner@chebucto.ns.ca >> <mailto:naturens-owner@chebucto.ns.ca> >> [mailto:naturens-owner@chebucto.ns.ca] *On Behalf Of *Donna Crossland >> *Sent:* June-22-16 19:20 >> *To:* naturens@chebucto.ns.ca <mailto:naturens@chebucto.ns.ca> >> *Subject:* [NatureNS] absence of insects >> >> >> >> In response to Susann’s question regarding whether other birders have >> noticed a lack of insects: I’ve noticed the past couple of years that >> black flies seem to ‘not be what they used to be’. Mostly, the season >> seems to be noticeably abbreviated. Also the past two spring have >> witness very cold temperatures in the mornings (last Saturday there was >> a frost at Milford House and only 4 C when I arrived at 5:20 am). I >> measure the temperature at every bird survey post and notice that 10-11 >> C is required before I need to put on some bug deterrent. By then, on >> most mornings until the warm temps of this week, I’ve pretty well >> completed the bird survey. >> >> >> >> Earlier this spring, some of the fishermen were commenting that the >> blackflies were biting just like in the old days. Things started out >> ‘normally’ enough, but then we hit the prolonged cold snap and waters >> were rapidly dropping, too. The blackflies quickly became less of an issue. >> >> >> >> I’m not a bug expert, but I grew up in one of the buggiest areas of the >> province. My theory with the black