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Quoting David & Alison Webster <dwebster@glinx.com>:
> I have not paid much attention to this beyond being aware that at
> infrequent times (almost by definition) there will be exceptional
> years. I am no doubt 50 years out of date but a widespread crop
> failure is to me suggestive of some widespread environmental effect.
* well, I'm only 30 years out of date, but I see wikipedia hasn't
gotten any further - http://en.wikipedia.org/wiki/Predator_satiation
> The idea that there could be some evolutionary advantage for all
> trees to swing and sway their seed production in unison, even if
> they could do it, is I think unsound.
* but it is generally accepted to be the case. In fact, the main
effect of favourable and unfavourable years is often held to be the
synchronization a population achieves from the stimulus of the
exceptional year, enabling them to subsequently co-ordinate their mast
and non-mast years.
fred.
=======================================================
>
> The journey of the typical tree seed, from release to oblivion,
> is almost certain to end in something other than a tree and
> seed-eating birds are just one hazard, in a decades-long gauntlet.
> that they must run; insects, birds, rodents, adverse soil,
> competition, browsers, girdling, fungi... the very few that survive
> all this remain at risk until a nearby large tree dies and they then
> may replace it if they are positioned in all respects better than
> other nearby young trees.
>
> Yt, Dave Webster, Kentville
>
>
> ----- Original Message ----- From: "Rick Whitman"
> <dendroica.caerulescens@gmail.com>
> To: <naturens@chebucto.ns.ca>
> Sent: Saturday, November 10, 2012 3:31 PM
> Subject: [NatureNS] Seed Cropping Strategy in Trees
>
>
>> Someone here knows more than I do. I think your focus is too much on
>> the negatives, to start with. I believe most tree seed crops, both
>> hardwood & softwood, are strongly cyclical over large areas. The
>> cycles may be pushed, or damped, from time to time by extreme good /
>> bad growing seasons, but I believe they will carry on regardless. As
>> you will know from your apple background, a very large crop one year
>> will almost always be followed by a small crop the next. The trees
>> simply don't have the resources to produce large crops every year.
>>
>> A fruit grower modulates crop load by hand thinners or chemical
>> thinners. No such thing exists in the wild and it's not obvious that
>> the trees would benefit from such. We think too much about how nuts
>> are spread around by birds and squirrels, to the trees' benefit. We
>> need to remember that this is not the case at all for most or all
>> softwoods & many hardwoods. I'm sure there are minor exceptions
>> (carried seeds being lost) but overall conifers, maples, ash, birch
>> etc. ALL distribute their seeds by the wind. Seed eating birds are
>> PREDATORS and nothing more.
>>
>> Therefore, it makes perfect evolutionary sense for widespread
>> populations of trees to synchronize their seed crops & overwhelm these
>> predators with abundance, in a highly cyclic fashion. The trees have
>> no "interest" in feeding these birds. The trees that are out of sync
>> will be heavily predated & will not reproduce.
>>
>> Now, someone can give the correct story.
>>
>> Rick Whitman
>>
>> On Sat, Nov 10, 2012 at 10:07 AM, David & Alison Webster
>> <dwebster@glinx.com> wrote:
>>> Hi Rick & All, Nov 10, 2012
>>> Is the distribution of this poor seed crop in 2012 associated with
>>> distribution of dry weather this year (poor set or poor
>>> development) or with
>>> adverse conditions in 2011 (fewer cones/flower buds) ?
>>> Yt, Dave Webster, Kentville
>>> ----- Original Message ----- From: "Rick Whitman"
>>> <dendroica.caerulescens@gmail.com>
>>> To: "naturens" <naturens@chebucto.ns.ca>
>>> Sent: Wednesday, November 07, 2012 1:34 PM
>>> Subject: [NatureNS] Winter Finch Forecast, Other Northern Birds
>>>
>>>
>>>> I'm pretty sure I didn't post Ron Pittaway's forecast for this winter
>>>> before. He predicted a big move out of the eastern North woods, but
>>>> they will only stay here in numbers if they like the conditions. I do
>>>> have my doubts about our coniferous cone crop & his article implies
>>>> the same:
>>>>
>>>> "The theme this winter is that each finch species will use a different
>>>> strategy to deal with the widespread tree seed crop failure in the
>>>> Northeast. It will be a quiet winter in the eastern North Woods. See
>>>> individual species forecasts for details. Both coniferous and hardwood
>>>> tree seed crops are generally poor from northeastern Ontario extending
>>>> eastward across Quebec to Newfoundland south through the Maritime
>>>> Provinces, New York and New England States. Within the Northeast there
>>>> are pockets of good crops. Cone crops are much better in the Hudson
>>>> Bay Lowlands and northwestern Ontario west to Alberta, Northwest
>>>> Territories and Yukon. Three irruptive non-finch passerines whose
>>>> movements are linked to finches are also discussed."
>>>>
>>>> His article is here:
>>>>
>>>> http://www.jeaniron.ca/2012/finchforecast2012.htm
>>>>
>>>> A number of you have been seeing Evening Grosbeaks & since Nov. 4 Ken
>>>> McKenna & Dominic Cormier have reported Pine Grosbeaks on eBird. I
>>>> also had 3 Pine Grosbeaks in my yard at White Rock yesterday. I don't
>>>> see any eBird reports of Common Redpolls in NS yet. Today I had 46 at
>>>> Horton Landing feeding in birches. So I've already seen 2 winter
>>>> finches that in some years I don't see all winter. It must be a winter
>>>> finch year.
>>>>
>>>> On a somewhat related note, I saw all of the following on the Grand
>>>> Pre dykelands today: Horned Lark, American Pipit, Lapland Longspur &
>>>> Snow Bunting. These have all been "around" but this speaks of winter
>>>> to me.
>>>>
>>>> Rick Whitman
>>
------------------------------------------------------------
Frederick W. Schueler & Aleta Karstad
Bishops Mills Natural History Centre - http://pinic