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Index of Subjects --Apple-Mail-2-11129661 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=US-ASCII; delsp=yes; format=flowed Hi Randy, Harmonia axyridis is indeed one of the introduced species of lady beetles (6 of the 47 species found in the Maritimes). Most of the research that I am aware related to the impact of introduced species on native ones has implicated another species, Coccinella septempunctata (the seven-spotted lady beetle), but this may be because C. septempunctata has been around longer and has been the subject of more research in the past. Given the phenomenal abundance of H. axyridis in some areas I would be surprised if they were not having some impact on native lady beetles (and other insects as well). Nonetheless, unfortunate as this may be, the cat is well and truly out of the bag by now since H. axyridis as now colonized the entire eastern United States as well as most areas in southeastern Canada and there are now robust populations in Washington, Oregon, California, and British Columbia. Even assiduously destroying every one that came within reach the effect would be far less even than the proverbial pinprick on an elephant (there must surely be hundreds of millions of H. axyridis in the Maritimes, if not more). Barring unforeseen circumstances we are now stuck with this species as a prominent part of our fauna. N.B. The cat may still be bagged on both Prince Edward Island and Cape Breton Island. Although I have found H. axyridis in all three counties on PEI, they have nonetheless remained rare there and there may be some chance that they will not permanently establish. David McCorquodale's work on Cape Breton Island showed that although the species arrived there in 1985, it seems to have subsequently disappeared. Perhaps winter conditions have proved too inclement for its survival there? On the other hand, if climate change proceeds apace, these circumstances may not hold true for very long ... Cheers! Chris On 22-Oct-07, at 10:41 AM, Randy Lauff wrote: > Multicoloured Asian Ladybird Beetles (Harmonia axyridis) > > "They don't seem to do any obvious harm in the house." > "Some of them get inside and when I'm there I dutifully collect > them and release them in the greenhouse where I hope they can put a > dent in the whitefly population..." > > Harm in the house...no...dent in the whitefly population, perhaps. > Cause a catastophic decline in our native species' numbers...isn't > this one of the foreign culprits that could be responsible? > > When they're in such large, accessible numbers, I'd take the > opportunity to destroy them. When I look at the choice between my > garden and nature as a whole, nature wins. And yes, I remove > earthworms from my garden, too. And I have a wonderful garden. > There is no need for for foreign species assistance in gardening, > not at the risk of the loss of natives. > > Randy > _________________________________ > RF Lauff > Way in the boonies of > Antigonish County, NS. _._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._. _. Christopher Majka - Nova Scotia Museum of Natural History 1747 Summer Street, Halifax, Nova Scotia, Canada B3H 3A6 (902) 424-6435 Email <c.majka@ns.sympatico.ca> _._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._. _. --Apple-Mail-2-11129661 Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=ISO-8859-1 <html><body style=3D"word-wrap: break-word; -webkit-nbsp-mode: space; = -webkit-line-break: after-white-space; "> Hi Randy,<div><br = class=3D"webkit-block-placeholder"></div><div><i>Harmonia axyridis</i> = is indeed one of the introduced=A0species=A0of lady beetles (6 of the 47 = species found in the Maritimes). Most of the research that I am aware = related to the impact of introduced species on native ones has = implicated =A0another species,<i> Coccinella septempunctata </i>(the = seven-spotted lady beetle), but this may be because <i>C. = septempunctata</i> has been around longer and has been the subject of = more research in the past. Given the phenomenal abundance of <i>H. = axyridis </i>in some areas I would be surprised if they were <i>not</i> = having some impact on native lady beetles (and other insects as = well).</div><div><br = class=3D"webkit-block-placeholder"></div><div>Nonetheless, unfortunate = as this may be, the cat is well and truly out of the bag by now since = <i>H. axyridis</i> as now colonized the entire eastern United States as = well as most areas in southeastern Canada and there are now robust = populations in Washington, Oregon, California, and British Columbia. = Even assiduously=A0destroying=A0every one that came within reach the = effect would be far less even than the proverbial pinprick on an = elephant (there must surely be hundreds of millions of <i>H. = axyridis</i> in the Maritimes, if not more). = Barring=A0unforeseen=A0circumstances we are now stuck with this species = as a prominent part of our fauna.</div><div><br = class=3D"webkit-block-placeholder"></div><div>N.B. The cat may still be = bagged on both Prince Edward Island and Cape Breton Island. Although I = have found <i>H. axyridis</i> in all three counties on PEI, they have = nonetheless remained rare there and there may be some chance that they = will not permanently establish. David McCorquodale's work on Cape Breton = Island showed that although the species arrived there in 1985, it seems = to have=A0subsequently=A0disappeared. Perhaps winter conditions have = proved too inclement for its survival there? On the other hand, if = climate change proceeds apace, these circumstances may not hold true for = very long ...</div><div><br = class=3D"webkit-block-placeholder"></div><div>Cheers!</div><div><br = class=3D"webkit-block-placeholder"></div><div>Chris</div><div><br><div><di= v>On 22-Oct-07, at 10:41 AM, Randy Lauff wrote:</div><br = class=3D"Apple-interchange-newline"><blockquote = type=3D"cite"><div>Multicoloured Asian Ladybird Beetles=A0(Harmonia = axyridis)</div> <div>=A0</div> <div>"