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There are certainly very few berries around, and the berry pro --Apple-Mail-46-468807807 Content-Type: text/plain; charset=ISO-8859-1; format=flowed; delsp=yes Content-Transfer-Encoding: quoted-printable Hi Eleanor, On 11-Nov-09, at 9:07 AM, Eleanor Lindsay wrote: > I think there are some very distinct regional differences in this =20 > year's wild food supply. The spruce bark beetle, which I understand =20= > is native to Nova Scotia and normally kept in check by cold =20 > winters...) has created quite severe and rapid devastation in some =20 > parts of the province, in particular the east side of St Margarets =20 > Bay, (especially Seabright and Glen Margaret), where whole chunks of =20= > spruce forest have died off in the space of the last 2-3 years and =20 > also, I believe in parts of Antigonish County and Cape Breton. So =20 > cones for squirrels, for example, must be severely reduced or non =20 > existent in these areas. In North America the name "spruce bark beetle" is normally applied to =20= Dendroctonus rufipennis, although in Europe, the name indicates =20 another species, Ips typographicus. Dendroctonus rufipennis is a =20 native species in Nova Scotia, indeed it occurs throughout North =20 America from Alaska to Newfoundland and south into the USA wherever =20 spruce grow. Although most of the recent attention on the relationship =20= of climate change to bark beetle infestations has been devoted to the =20= mountain pine beetle (Dendroctonus ponderosae), there are considerable =20= similarities between the two species. There are two climate related =20 effects: 1) Prolonged cold temperatures during the winter can kill some of the =20= overwintering beetles. As we experience climate change, and prolonged =20= cold snaps in winter become less frequent, this bioregulation =20 mechanism becomes less effective. For example, studies in the southern =20= United States on the similar southern pine beetle (Dendroctonus =20 frontalis) have linked outbreaks there to a warming trend from 1960 to =20= 2004 of 3.3=B0C in minimum winter air temperatures. 2) Spruce bark beetles normally complete their life cycles in either =20 one or two years (rarely three, in cold northern regions). As climate =20= changes and temperatures warm, a greater proportion of beetles can =20 complete their life cycles in a shorter period of time, leading to =20 faster turnover and greater utilization of resources (i.e., they chew =20= through spruce more quickly ;->). In other bark beetles, for instance in the genus Ips, that are =20 sometimes univoltine (i.e., one generation per year), or bivoltine =20 (two generations per year), warming temperatures mean that a greater =20 proportion of the population becomes bivoltine, again with the same =20 consequences: population levels increase and they consume more food =20 (most bark beetles are cambium feeders, feeding on the inner bark of =20 trees). The USDA Forest Service has a good web page on Dendroctonus rufipennis: http://www.na.fs.fed.us/spfo/pubs/fidls/sprucebeetle/sprucebeetle.htm Cheers! Chris Christopher Majka <c.majka@ns.sympatico.ca> | Halifax, Nova Scotia, =20 Canada * Research Associate: Nova Scotia Museum | = http://museum.gov.ns.ca/mnh/research-asfr.htm * Review Editor: The Coleopterists Bulletin | http://www.coleopsoc.org/ * Subject Editor: ZooKeys | = http://pensoftonline.net/zookeys/index.php/journal/index * Associate Editor: Journal of the Acadian Entomological Society | = http://www.acadianes.org/journal.html * Editor: Atlantic Canada Coleoptera | = http://www.chebucto.ns.ca/Environment/NHR/atlantic_coleoptera.html "Whenever I hear of the capture of rare beetles, I feel like an old =20 war-horse at the sound of a trumpet." - Charles Darwin --Apple-Mail-46-468807807 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable <html><body style=3D"word-wrap: break-word; -webkit-nbsp-mode: space; = -webkit-line-break: after-white-space; ">Hi = Eleanor,<div><br><div><div>On 11-Nov-09, at 9:07 AM, Eleanor Lindsay = wrote:</div><br class=3D"Apple-interchange-newline"><blockquote = type=3D"cite"><div>I think there are some very distinct regional = differences in this year's wild food supply. The spruce bark beetle, = which I understand is native to Nova Scotia and normally kept in check = by cold winters...) has created quite severe and rapid devastation in = some parts of the province, in particular the east side of St Margarets = Bay, (especially Seabright and Glen Margaret), where whole chunks of = spruce forest have died off in the space of the last 2-3 years and also, = I believe in parts of Antigonish County and Cape Breton. So cones for = squirrels, for example, must be severely reduced or non existent in = these areas.<br></div></blockquote></div><br></div><div>In North America = the name "spruce bark beetle" is normally applied to <i>Dendroctonus = rufipennis</i>, although in Europe, the name indicates another species, = <i>Ips typographicus</i>. <span class=3D"Apple-style-span" = style=3D"font-style: italic; ">Dendroctonus rufipennis</span> is a = native species in Nova Scotia, indeed it occurs throughout North America = from Alaska to Newfoundland and south into the USA wherever spruce grow. = Although most of the recent attention on the relationship of climate = change to bark beetle infestations has been devoted to the mountain pine = beetle (<i>Dendroctonus ponderosae</i>), there are considerable = similarities between the two species. There are two climate related = effects:</div><div><br></div><div>1) Prolonged cold temperatures during = the winter can kill some of the overwintering beetles. As we experience = climate change, and prolonged cold snaps in winter become less frequent, = this bioregulation mechanism becomes less effective. For example, = studies in the southern United States on the similar southern pine = beetle (<i>Dendroctonus frontalis</i>) have linked outbreaks there = to a warming trend from 1960 to 2004 of 3.3=B0C in minimum winter = air temperatures.</div><div><br></div><div>2) Spruce bark beetles = normally complete their life cycles in either one or two years (rarely = three, in cold northern regions). As climate changes and temperatures = warm, a greater proportion of beetles can complete their life cycles in = a shorter period of time, leading to faster turnover and greater = utilization of resources (i.e., they chew through spruce more quickly = ;->). </div><div><br></div><div>In other bark beetles, for = instance in the genus <i>Ips</i>, that are s