scholarly journals Patterns of Consumption and Diet Differentiation for Three Breeding Warbler Species During a Spruce Budworm Outbreak

The Auk ◽  
2002 ◽  
Vol 119 (1) ◽  
pp. 216-220 ◽  
Author(s):  
B. McMartin ◽  
I. Bellocq ◽  
S. M. Smith
Keyword(s):  
Boreal Forest ◽  
Breeding Season ◽  
Spruce Budworm ◽  
The Other ◽  
Food Category ◽  
Northern Ontario ◽  
Food Items ◽  
Species Pairs ◽  
Food Niche

Abstract Diets of three warbler species were analyzed during a spruce budworm outbreak in the boreal forest of northern Ontario. Beetles constituted a large portion of the food items consumed by Cape May (Dendroica tigrina), Bay-breasted (Dendroica castanea), and Tennessee (Vermivora peregrina) warblers early in the breeding season (7–11 June), and caterpillars were the most frequently used food category shortly later (18–24 June). Differences in diet served to differentiate the warbler species in the earlier period when Bay-breasted Warblers consumed more beetles, Tennessee Warblers consumed more caterpillars, and Cape May Warblers consumed more flies than the other species. Only Bay-breasted Warblers' continuing preference for beetles differentiated the warblers' diets in the later period. Food-niche overlaps increased for two of the three warbler species pairs between the two periods in June, but there was no change in the overlap between Bay-breasted and Cape May warbler diets.

scholarly journals Epidemiology of the Spruce Budworm in Western Ontario: A Discussion

1985 ◽  
Vol 61 (6) ◽  
pp. 494-498 ◽  
Author(s):  
J. R. Blais
Keyword(s):  
Boreal Forest ◽  
Key Words ◽  
Choristoneura Fumiferana ◽  
Abies Balsamea ◽  
Spruce Budworm ◽  
The Other ◽  
Balsam Fir ◽  
The Past ◽  
Future Behavior ◽  
High Concentrations

Spruce budworm outbreaks for the past two centuries in western Ontario occurred in two main sectors, the Lake Nipigon and the Lac Seul sectors. Some were common to both sectors, while others were specific to one or the other. Intervals between infestations within sectors averaged about 60 years. For western Ontario, budworm populations oscillated at irregular intervals ranging from 15 to 60 years. Infestations generally originated in the boreal forest in centers with high concentrations of fir, and then appeared in areas with lower volumes of fir. Fir content and the susceptibility to budworm attack of forests in western Ontario are compared with conditions prevailing in Quebec and the Maritimes. There are new outbreaks in western Ontario, and their future behavior could clarify some aspects of budworm epidemiology. Key words: Spruce budworm, Choristoneura fumiferana; Balsam fir, Abies balsamea (L.) Mill.; Epidemiology.

scholarly journals Species-Specific Segregation of Gender-Associated Mitochondrial DNA Types in an Area Where Two Mussel Species (Mytilus edulis and M. trossulus) Hybridize

Genetics ◽  
1996 ◽  
Vol 143 (3) ◽  
pp. 1359-1367 ◽  
Author(s):  
Carlos Saavedra ◽  
Donald T Stewart ◽  
Rebecca R Stanwood ◽  
Eleftherios Zouros
Keyword(s):  
Mytilus Edulis ◽  
The Other ◽  
Allozyme Analysis ◽  
Mussel Species ◽  
Species Origin ◽  
Species Pairs ◽  
Nuclear Background ◽  
Species Specific ◽  
Dna Types ◽  
Fertile Hybrids

Abstract In each of the mussel species Mytilus edulis and M. trossulus there exist two types of mtDNA, the F type transmitted through females and the M type transmitted through males. Because the two species produce fertile hybrids in nature, F and M types of one may introgress into the other. We present the results from a survey of a population in which extensive hybridization occurs between these two species. Among specimens classified as “pure” M. edulis or “pure” M. trossulus on the basis of allozyme analysis, we observed no animal that carried the F or the M mitotype of the other species. In most animals of mixed nuclear background, an individual's mtDNA came from the species that contributed the majority of the individual's nuclear genes. Most importantly, the two mtDNA types in post-F1 male hybrids were of the same species origin. We interpret this to mean that there are intrinsic barriers to the exchange of mtDNA between these two species. Because such barriers were not noted in other hybridizing species pairs (many being even less interfertile than M. edulis and M. trossulus), their presence in Mytilus could be another feature of the unusual mtDNA system in this genus.

GROUND RELEASES OF TRICHOGRAMMA MINUTUM RILEY (HYMENOPTERA: TRICHOGRAMMATIDAE) AGAINST THE SPRUCE BUDWORM (LEPIDOPTERA: TORTRICIDAE)

1987 ◽  
Vol 119 (3) ◽  
pp. 251-263 ◽  
Author(s):  
S.M. Smith ◽  
M. Hubbes ◽  
J.R. Carrow
Keyword(s):  
Optimal Strategy ◽  
Choristoneura Fumiferana ◽  
Spruce Budworm ◽  
Egg Mass ◽  
Northern Ontario ◽  
Inundative Release ◽  
Egg Masses ◽  
Trichogramma Minutum ◽  
Spruce Stands ◽  
Natural Parasitism

AbstractDuring 1982 and 1984, ground releases of Trichogramma minutum Riley were assessed for control of the spruce budworm, Choristoneura fumiferana (Clemens), on 12- to 20-year-old, white spruce stands in northern Ontario. Maximum parasitism of susceptible egg masses was 16 and 87% following the release of 480 000 and 12 million female T. minutum per hectare, respectively. Releases at intervals of 1 week maintained parasitism of susceptible egg masses at constant levels throughout the oviposition period of spruce budworm. When parasitism of susceptible egg masses was maintained above 78.2% during the ovipositional period, total egg mass parasitism averaged 58.0% and resulted in an 80.3% reduction of overwintering 2nd-instar larvae. The optimal strategy for reducing spruce budworm was two releases of T. minutum at an interval of 1 week in the ovipositional period. This allowed a second generation of parasitoids to emerge from the spruce budworm eggs that were more efficient in maintaining high levels of parasitism than those emerging from the standard rearing host. Natural parasitism of spruce budworm egg masses was less than 4% and there was no carryover of parasitism in the years following inundative release. The rate of T. minutum release necessary to achieve effective mortality of spruce budworm during outbreak populations is discussed briefly.

Effects of commercial thinning on site occupancy and habitat use by spruce grouse in boreal Quebec

2011 ◽  
Vol 41 (3) ◽  
pp. 501-508 ◽  
Author(s):  
Ambroise Lycke ◽  
Louis Imbeau ◽  
Pierre Drapeau
Keyword(s):  
Habitat Use ◽  
Boreal Forest ◽  
Breeding Season ◽  
Vegetation Cover ◽  
Forest Cover ◽  
Site Occupancy ◽  
Lower Proportion ◽  
Large Mammals ◽  
Dense Vegetation ◽  
Commercial Thinning

Partial cuts are increasingly proposed to maintain habitats for species negatively affected by clearcutting, even if their benefits on nonpasserine birds and large mammals are still poorly documented. Our main objective was to evaluate effects of commercial thinning (CT) on spruce grouse ( Falcipennis canadensis L.), a game bird of the boreal forest. Because this species is known to be associated with a dense vegetation cover, we hypothesized that habitat use would be lower in treated sites. In spring 2006, we evaluated site occupancy in 94 forest stands (50 CT and 44 uncut stands) in Quebec by visiting each on three occasions during the breeding season (March–May). Additionally, during the molting period (May–July), we used radiotelemetry to monitor habitat use by 19 males. As compared with uncut stands, results show that a lower proportion of CTs were used in spring (39% versus 60%, after accounting for detection). During the molting period, CTs were also used less than expected according to their availability. The significant reduction of lateral and vertical forest cover in CT may explain these results. We conclude that even if CT is perceived beneficial for wildlife, it does not completely fulfill the needs of species associated with dense understory vegetation, such as spruce grouse.

Sixty Percent of Foods Advertised in Grocery Store Flyers are Not In-line with Canada’s Food Guide

2022 ◽  
pp. 1-7
Author(s):  
Natalie A. Laframboise ◽  
Jamie A. Seabrook ◽  
June I. Matthews ◽  
Paula D. N. Dworatzek
Keyword(s):  
Food Environment ◽  
Food Group ◽  
Grocery Store ◽  
Government Policies ◽  
Food Category ◽  
Food Items

Purpose: To evaluate foods advertised in discount and premium grocery flyers for their alignment with Canada’s 2007 Food Guide (CFG) and assess if alignment differed by food category, season, page location, and price. Methods: Weekly flyers (n = 192) were collected from discount and premium grocery chains from each of 4 seasons. Health Canada’s Surveillance Tool was used to assess food items as in-line or not in-line with CFG. Results: Of 35 576 food items, 39.7% were in-line with CFG. There were no differences in proportions of foods not in-line in discount versus premium flyers (60.9% and 60.0%, respectively). Other Foods and Meat & Alternatives were advertised most (28.0% and 26.3%, respectively; P < 0.001). Milk & Alternatives were the least advertised food group (10.3%). Vegetables & Fruit (19.6%), Grains (21.6%), Milk & Alternatives (20.6%), and Meat & Alternatives (20.2%) were promoted least in Fall (P < 0.001). A higher proportion of foods advertised on middle pages were not in-line (61.0%) compared with front (56.6%) and back (58.8%) pages (P < 0.001). Not in-line foods were more expensive ($3.49, IQR = $2.82) than in-line foods ($3.28, IQR = $2.81; P < 0.001). Conclusions: While there was no difference in healthfulness of foods advertised in discount versus premium flyers, grocers advertised more foods not in-line with CFG. Government policies to improve the food environment should consider grocery flyers.

scholarly journals Phenological synchrony between eastern spruce budworm and its host trees increases with warmer temperatures in the boreal forest

2018 ◽  
Vol 9 (1) ◽  
pp. 576-586 ◽  
Author(s):  
Deepa S. Pureswaran ◽  
Mathieu Neau ◽  
Maryse Marchand ◽  
Louis De Grandpré ◽  
Dan Kneeshaw
Keyword(s):  
Boreal Forest ◽  
Spruce Budworm ◽  
Eastern Spruce Budworm ◽  
Host Trees ◽  
Phenological Synchrony

Age and food hardness affect food handling by insectivorous bats

2007 ◽  
Vol 85 (9) ◽  
pp. 985-993 ◽  
Author(s):  
E.E. Fraser ◽  
M.B. Fenton
Keyword(s):  
Optimal Foraging ◽  
Feeding Behaviour ◽  
Eating Behaviour ◽  
Myotis Lucifugus ◽  
The Other ◽  
Food Handling ◽  
Insectivorous Bats ◽  
Male And Female ◽  
Food Items ◽  
And Gender

Eating behaviour can vary with age, experience, and gender, as well as food hardness. This variation can contribute to intraspecific dietary differences and may result in variable definitions of optimal foraging and decreased intraspecific competition. We quantified feeding behaviour of insectivorous bats eating hard and soft mealworm-based food items based on the bats’ ability to consume and manipulate food items, consumption time, chew frequency, and total chews to consume. Adult Myotis lucifugus (LeConte, 1831) were more successful at both consuming and manipulating mealworms and consumed mealworms more quickly, with greater chew frequency and in fewer chews, than did subadults. Adults chewed mealworm viscera more frequently than did subadults but showed no differences in the other variables. Adult Eptesicus fuscus (Beauvois, 1796) consumed mealworms more quickly and with fewer chews than did subadults but showed no differences in the other variables. There were no differences between adult and subadult E. fuscus when consuming mealworm viscera. Male and female M. lucifugus did not differ significantly when eating either mealworms or mealworm viscera. There was no change in subadult consumption time of mealworms over the summer. Age-based differences in eating abilities may play a role in defining optimal foraging and dietary composition in insectivorous bats.

Classification of annual non-stand replacing boreal forest change in Canada using Landsat time series: a case study in northern Ontario

2016 ◽  
Vol 8 (1) ◽  
pp. 29-37 ◽  
Author(s):  
Oumer S. Ahmed ◽  
Michael A. Wulder ◽  
Joanne C. White ◽  
Txomin Hermosilla ◽  
Nicholas C. Coops ◽  
...  
Keyword(s):  
Time Series ◽  
Boreal Forest ◽  
Forest Change ◽  
Northern Ontario

scholarly journals Structural dynamics at boreal forest edges created by a spruce budworm outbreak

Silva Fennica ◽  
2015 ◽  
Vol 49 (3) ◽  
Author(s):  
Caroline Franklin ◽  
Karen Harper ◽  
Liam Murphy
Keyword(s):  
Boreal Forest ◽  
Structural Dynamics ◽  
Spruce Budworm ◽  
Forest Edges

BEETLES THAT CANNOT BITE: FUNCTIONAL MORPHOLOGY OF THE HEAD OF ADULT RHYSODINES (COLEOPTERA: CARABIDAE OR RHYSODIDAE)

1994 ◽  
Vol 126 (3) ◽  
pp. 667-672 ◽  
Author(s):  
Ross T. Bell
Keyword(s):  
Functional Morphology ◽  
The Other ◽  
Internal Cavity ◽  
Wood Fibers ◽  
Slime Molds ◽  
Food Items ◽  
Jaw Musculature

AbstractIn Rhysodini the greatly enlarged mentum forms the entering edge as the beetle wedge-pushes its way through wood. The mandibles cannot bite either wood fibers or food items, but function as a cover for the other mouthparts. The palpi are completely retractile. Each maxilla bears two stylets, the galea and lacinia, and the ligula consists of two bilobed structures. These are apparently the sole feeding structures enabling the beetles to prey on the amoeboid stage of slime molds. The large internal cavity of the head is interpreted as a compromise between a greatly reduced head volume, resulting from reduced jaw musculature, and the need to retain the surface of a full-sized head as part of the wedge-pushing apparatus.

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