Behaviour of spruce grouse broods in the field

1985 ◽  
Vol 63 (11) ◽  
pp. 2494-2500 ◽  
Author(s):  
Michael A. Schroeder ◽  
David A. Boag

Behaviour of juvenile spruce grouse (Dendragapus canadensis), from hatching to brood breakup, was observed in 30 radio-tracked broods inhabiting lodgepole pine (Pinus contorta) forests of southwestern Alberta. The immediate posthatch period (first 20 days) was characterized by a close spatial relationship between the chicks and hen, with brooding being the dominant behaviour. Hens with broods appeared to respond immediately, both vocally and through movement toward their chicks, whenever the latter uttered the following calls: sreep, sury, seer, and purring. Brooding sessions decreased in frequency but not duration (median of 11 min) until they disappeared from the behavioural repertoire of the chicks at about 50 days of age. Hen–chick and intersibling distances increased as the chicks grew older. The breakup of broods appeared to result when the cohesiveness of the brood decreased to a point at which calls of the chicks no longer elicited a response from the brood hen. There was no evidence that agonism contributed to this decline in brood cohesion.

Author(s):  
Ruth V.W. Dimlich

Mast cells in the dura mater of the rat may play a role in cerebral pathologies including neurogenic inflammation (vasodilation; plasma extravasation) and headache pain . As has been suggested for other tissues, dural mast cells may exhibit a close spatial relationship to nerves. There has been no detailed ultrastructural description of mast cells in this tissue; therefore, the goals of this study were to provide this analysis and to determine the spatial relationship of mast cells to nerves and other components of the dura mater in the rat.Four adult anesthetized male Wistar rats (290-400 g) were fixed by perfusion through the heart with 2% glutaraldehyde and 2.8% paraformaldehyde in a potassium phosphate buffer (pH 7.4) for 30 min. The head of each rat was removed and stored in fixative for a minimum of 24 h at which time the dural coverings were removed and dissected into samples that included the middle meningeal vasculature. Samples were routinely processed and flat embedded in LX 112. Thick (1 um) sections from a minimum of 3 blocks per rat were stained with toluidine blue (0.5% aqueous).


2011 ◽  
Vol 41 (12) ◽  
pp. 2403-2412 ◽  
Author(s):  
Daniel M. Kashian ◽  
Rebecca M. Jackson ◽  
Heather D. Lyons

Extensive outbreaks of the mountain pine beetle ( Dendroctonus ponderosae Hopkins) will alter the structure of many stands that will likely be attacked again before experiencing a stand-replacing fire. We examined a stand of lodgepole pine ( Pinus contorta var. latifolia Engelm. ex S. Watson) in Grand Teton National Park currently experiencing a moderate-level outbreak and previously attacked by mountain pine beetle in the 1960s. Consistent with published studies, tree diameter was the main predictor of beetle attack on a given tree, large trees were preferentially attacked, and tree vigor, age, and cone production were unimportant variables for beetle attack at epidemic levels. Small trees killed in the stand were killed based mainly on their proximity to large trees and were likely spatially aggregated with large trees as a result of the previous outbreak. We concluded that the driving factors of beetle attack and their spatial patterns are consistent across outbreak severities but that stand structure altered by the previous outbreak had implications for the current outbreaks in the same location. This study should catalyze additional research that examines how beetle-altered stand structure affects future outbreaks — an important priority for predicting their impacts under climate change scenarios that project increases in outbreak frequency and extent.


2005 ◽  
Vol 35 (6) ◽  
pp. 1314-1318 ◽  
Author(s):  
Peter V Blenis ◽  
Wuhan Li

Infection of lodgepole pine (Pinus contorta Dougl. ex Loud. var. latifolia Engelm.) by western gall rust has been shown to decrease with tree height and age, but the effects of those two factors have not been separated. Five replicate artificial inoculations were done on a total of 327 trees of different ages in two height classes. Temperature and percentage of spore germination at the height of inoculation, shoot development (stem elongation at the time of inoculation as a proportion of final shoot elongation), main stem leader length at the time of inoculation, tree height, and tree age were measured. Modeled percentages of infected trees and the number of galls per 10 cm of shoot length decreased by 85% and 88%, respectively, as tree age increased between 2 and 10 years, indicating the undesirability of early, aggressive precommercial thinning of lodgepole pine stands in areas where western gall rust is common. By controlling and (or) statistically accounting for inoculum, microclimate, and phenological factors, it was possible to demonstrate that changes in susceptibility with tree age are sufficient to account for the reduction in infection with tree height.


2009 ◽  
Vol 15 (3) ◽  
pp. 535-548 ◽  
Author(s):  
E. A. H. SMITHWICK ◽  
M. G. RYAN ◽  
D. M. KASHIAN ◽  
W. H. ROMME ◽  
D. B. TINKER ◽  
...  

1986 ◽  
Vol 64 (10) ◽  
pp. 2368-2371 ◽  
Author(s):  
Keith N. Egger ◽  
J. W. Paden

Forty isolates of postfire ascomycetes (Pezizales) were tested for in vitro pathogenicity on seeds and germinants of lodgepole pine, Pinus contorta Dougl. Two known pathogens, Caloscypha fulgens (Pers.) Boud. and Botrytis cinerea Pers., were included as a check of the method. Caloscypha fulgens was the only fungus that caused serious declines in seed germination, although several species of postfire Pezizales were capable of preemergence seed infection. Rhizina undulata Fr. and Pyropyxis rubra (Peck) Egger were strongly pathogenic on germinants. Pyropyxis rubra was not previously known to be pathogenic. Many isolates were weakly pathogenic on germinants under the conditions tested.


2014 ◽  
Vol 64 ◽  
pp. 161-170 ◽  
Author(s):  
Zaki-ul-Zaman Asam ◽  
Mika Nieminen ◽  
Connie O’Driscoll ◽  
Mark O’Connor ◽  
Sakari Sarkkola ◽  
...  

1989 ◽  
Vol 121 (6) ◽  
pp. 521-523 ◽  
Author(s):  
A.J. Stock ◽  
R.A. Gorley

The mountain pine beetle, Dendroctonus ponderosae Hopk., causes extensive mortality of lodgepole pine, Pinus contorta var. latifolia Engelm., throughout western North America (Van Sickle 1982). The Prince Rupert Forest Region, in the northwest of British Columbia, initiated an aggressive beetle management program in 1981. Logging of infested stands, and winter felling and burning of individual infested trees are the most common direct control techniques.The “Bristol Lake” infestation developed in the Bulkley Forest District, approximately 55 km northwest of Smithers, B.C., on a steep rocky ridge within the valley of Harold Price Creek. The area contained large volumes of mature lodgepole pine, and control of the infestation was therefore considered critical to the local beetle management plan, but the size (50 ha) and rough topography of the infested area precluded normal direct control measures.


Botany ◽  
2012 ◽  
Vol 90 (9) ◽  
pp. 891-896 ◽  
Author(s):  
Amandeep Bal ◽  
Christopher P. Chanway

Diazotrophic bacteria previously isolated from internal tissues of naturally regenerating lodgepole pine ( Pinus contorta var. latifolia (Dougl.) Engelm.) seedlings were tested for their ability to colonize and fix nitrogen (N) in pine germinants in two experiments. Surface sterilized pine seed was sown in glass tubes containing an autoclaved sand – montmorillonite clay mixture that contained a N-limited nutrient solution labeled with 15N as 0.35 mmol·L–1 Ca(15NO3)2 (5% 15N label). Pine seed was inoculated with one of three of the following bacterial strains: Paenibacillus polymyxa P2b-2R, P. polymyxa P18b-2R, or Dyadobacter fermentans P19a-2R, and seedlings grew for either 27 or 35 weeks. At the end of each plant growth period, P. polymyxa strain P2b-2R was detected in the pine rhizosphere but not inside plant tissues. Pine foliar N concentrations were not affected by bacterial inoculation but significant foliar 15N dilution was observed in seedlings treated with strain P2b-2R (30% and 66%, P < 0.05, in the first and second experiments, respectively). This strain also reduced seedling biomass in both experiments but effects were significant only in the second experiment (36%, P < 0.05). Notwithstanding the negative effect of bacterial inoculation on seedling growth, pine seedlings inoculated with strain P2b-2R derived 30% and 66%, respectively, of their foliar N from bacterial N fixation in two seedling growth experiments. These results demonstrate the possibility that some endophytic diazotrophs facilitate pine seedling growth in N-poor soils.


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