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Copyright of Ecoscience (Ecoscience) is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Alternative successional trajectories (AST) may result in multiple climax states within an ecosystem when disturbances affect colonization history. In the boreal forest, ungulates have been proposed to drive AST because, under herbivore pressure, preferred species may go extinct and apparent competition may benefit browsing-resistant species. Over a 15-year period following logging, we tested whether deer herbivory altered plant species composition and whether the competitive advantage of resistant species was maintained following herbivore removal. We compared exclosures built immediately after logging with delayed exclosures built eight years later on Anticosti Island, Quebec, Canada. Although the palatable tree Be tula papyrifera (paper birch) and some palatable herbs recovered in delayed exclosures, we observed legacies in both tree and herb cover. Woody regeneration in delayed exclosures was dominated by Picea glauca (white spruce), and Poaceae (grasses) were abundant in the field layer. Given that only early-successional species recovered, whereas latesuccessional broadleaf species and Abies balsamea (balsam fir) remained rare, succession may follow an AST after a limited browsing period during early succession. [ABSTRACT FROM AUTHOR]

Abstract: A detailed study of Late Ordovician–early Silurian acritarchs (Palaeozoic phytoplankton) from Anticosti Island (Québec, Canada) revealed an unusually high abundance of abnormal forms from the upper Hirnantian carbonate strata (uppermost Ordovician) of the Ellis Bay Formation in the western part of the island (member 6, Spinachitina taugourdeaui chitinozoan Biozone). The objective of this paper is to describe these abnormal forms in detail. Two species are particularly affected: Disparifusa psakadoria Loeblich and Tappan, 1978 presents abnormally hypertrophied central vesicles, whereas Peteinosphaeridium laframboisepointense nov. sp. has appendices that are fused along their length. The abnormal forms of acritarchs occur in rocks deposited during periods that are near time-equivalents to those of maximum ice-sheet extensions on Gondwana during the Hirnantian glaciation. Although this stratigraphic level corresponds to an interval of strong perturbations of the global carbon cycle, the exact factors causing the observed malformations remain unknown. [Copyright &y& Elsevier]

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: Browsing by the substantial population of white-tailed deer (Odocoileus virginianus Zimmermann) on Anticosti Island hampers the regeneration of balsam fir (Abies balsamea (L.) Mill.), which is both the deer''s preferred food and shelter. The island''s original fir stands have gradually been replaced by stands of white spruce (Picea glauca (Moench) Voss), as this species is rarely browsed by the deer. This project assesses the impact on the regeneration of balsam fir and companion species by large clearcuts performed using cutting with protection of regeneration and soils (CPRS). To this end, fenced-off areas adjacent to unfenced areas were established in 1995 and 1996 in large CPRS clearcuts. The results show that the distance from forest edge does not influence the stocking, number and height of seedlings, while browsing does reduce these variables in the case of fir and paper birch (Betula papyrifera Marsh.). However, stocking, number and height of white spruce seedlings were unaffected by both deer browsing and distance from forest edge. Woody debris seemed to protect balsam fir seedlings from browsing 8 years after cutting, but this protection should likely stop when seedlings will outgrow woody debris. It thus appears that large CPRS clearcuts will not permit the regeneration of balsam fir on a level sufficient for re-establishing fir stands on Anticosti Island. [Copyright &y& Elsevier]

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background During an inventory of insect diversity on Anticosti Island in 1993, we caught unprecedented numbers of Neospondylis upiformis (Mannerheim), a longhorned beetle rarely observed in eastern North America. All specimens were caught using 12-funnel Lindgren traps baited with 95% ethanol and α-pinene. This longhorned beetle was captured again in 2007 on Anticosti with the same traps. Other than that, seven specimens of N. upiformis were caught elsewhere in Quebec between 1993 and 2015. Only 14 specimens were found in the 45 most important insect collections of the province, the most recent specimen dating back to 1964. New information At least 90% of the captures came from old-growth balsam fir stands of the south-central part of the island. Seasonal flight activity ranged from early June to late July, but adult captures peaked in early July. Results suggest that Anticosti Island might be a hot spot for N. upiformis in eastern North America, particularly in its south-central part where oldgrowth balsam fir forests still exist. [ABSTRACT FROM AUTHOR]

Few empirical studies on large herbivores considered how behavioral plasticity could enhance their capacity to cope with rapid and extreme changes in weather conditions at several spatiotemporal scales. During winter, large herbivores living under low predation pressure mainly trade-off benefits of forage acquisition with the costs of exposure to harsh weather conditions. We assessed the changes in this trade-off for white-tailed deer adult females on Anticosti Island (Canada) at different scales during 2 contrasted winters (i.e., a harsher and a milder winter). We hypothesized that deer should adjust their foraging decisions to avoid cold wind-chill temperatures and high locomotion costs in deep snow as winter severity increased. We compared habitat selection at the homerange scale, habitat selection relative to thermal conditions within the home range, and selection for foraging sites relative to snow conditions along the foraging tracks between winters. Home-range selection of deer was similar between winters. Deer adjusted their within-home-range selection relative to thermal conditions: they selected thermal cover during cold-stress periods while their selection for open areas increased during the warmer periods. Deer showed high behavioral plasticity along their foraging tracks: they selected tracks with different forage resources between winters and traded-off the locomotion costs in deep snow cover with the benefits of forage availability as winter severity increased. We discuss how behavioral plasticity of deer in their thermoregulatory behavior and foraging site selection allows them to cope with varying winter conditions, in a system where their short-term behavioral adaptations were already strongly constrained by intraspecific competition. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The island rule refers to the tendency of small vertebrates to become larger when isolated on islands and the frequent dwarfing of large forms. It implies genetic control, and a necessary linkage, of size and body-mass differences between insular and mainland populations. To examine the island rule, we compared body size and mass of gray jays ( Perisoreus canadensis) on Anticosti Island, Québec, located in the Gulf of St. Lawrence, with three mainland populations (2 in Québec and 1 in Ontario). Although gray jays on Anticosti Island were ca 10% heavier, they were not structurally larger, than the three mainland populations. This suggests that Anticosti jays are not necessarily genetically distinct from mainland gray jays and that they may have achieved their greater body masses solely through packing more mass onto mainland-sized body frames. As such, they may be the first-known example of a proposed, purely phenotypic initial step in the adherence to the island rule by an insular population. Greater jay body mass is probably advantageous in Anticosti's high-density, intensely competitive social environment that may have resulted from the island's lack of mammalian nest predators. [ABSTRACT FROM AUTHOR]

Browsing by overabundant deer modifies plant communities and alters forest regeneration, which can indirectly impact associated insect fauna. We tested the hypothesis that the response of insect communities to changes in deer abundance should depend on the strength of their association with plants, which we considered as a key functional trait. Seven years after a deer density control experiment was established in partly harvested forests on Anticosti Island (Quebec, Canada), we evaluated the effects of reducing white-tailed deer ( Odocoileus virginianus) density from >20 down to 15, 7.5 and 0 deer km, on four insect taxa representing different levels of dependence on plants. As predicted by our hypothesis, the sensitivity of insect taxa to deer density decreased along a gradient representing their degree of association with plants. Carabidae remained unaffected, while Apoidea and Syrphidae communities differed between uncontrolled and reduced deer densities, but not as clearly as for Lepidoptera. As expected, insect communities responded faster in harvested than in forested areas because vegetation changes more rapidly in open habitats. For most insect taxa, dominant species were the most strongly affected by deer density reduction, but it was clearly stronger for predator taxa (Syrphidae and Carabidae). A fast recovery of rare species was observed for macro Lepidoptera. Reducing deer density down to 15 deer km is sufficient to restore insect diversity on Anticosti Island, but it is unlikely to be efficient in all situations, particularly when competing tree regeneration is firmly established. [ABSTRACT FROM AUTHOR]

Copyright of Ecoscience (Ecoscience) is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

1. The density of large herbivores is a major driver of forest ecosystem structure and function in conjunction with episodic disturbances, especially in forests with a regeneration strategy based on shade-tolerant seedlings capable of re-establishing canopy dominance (advance regeneration). Yet, uncertainty about the relationships between forest regeneration, herbivore density and other disturbances makes it difficult to set population goals. Using an innovative controlled browsing experiment, we investigated the relationships between the regeneration dynamics of balsam fir Abies balsamea, the density of white-tailed deer Odocoileus virginianus and timber harvesting. 2. We hypothesize that advance tree regeneration either: (i) recovers approximately linearly as deer density is reduced; (ii) recovers exponentially; or (iii) does not recover because factors other than browsing control advance regeneration. We tested these alternatives through manipulation of deer densities (0, 7·5, 15 deer km−2 and in situ local densities) and forest cover (clearcut and uncut forest). 3. Balsam fir seedling mortality decreased exponentially with decreasing deer density in clearcut and approximately linearly in uncut forest. Independently of deer density, the recruitment of seedlings in clearcut dropped from 56 ± 5% to 7 ± 1% within 3 years. 4. Seedling growth increased exponentially with decreasing deer density in clearcut whereas no height growth was observed in uncut forest. 5. Overall, the abundance of fir saplings recovered exponentially in clearcut but remained low and independent of deer density in uncut forest. The abundance of spruce Picea spp. saplings was unrelated to deer density and increased with time. 6. Synthesis and applications. Forest disturbance from selective browsing at high deer densities over an extended period of time leads to recruitment failure following a canopy disturbance such as a clearcut. Indirect competitive advantage given to species resistant to browsing can shift forest composition. Nonlinear relationships between fir regeneration and deer densities imply that the level of culling required to reach herbivore densities compatible with natural regeneration of native forest is larger than expected if tree regeneration was proportional to deer density. In the boreal forest of Anticosti Island, local densities < 15 deer km−2 achieved within 3 years following clearcut are compatible with the maintenance of native forest. [ABSTRACT FROM AUTHOR]

We assessed winter forage selection by white-tailed deer (Odocoileus virginianus) on Anticosti Island, Quebec, Canada, using cafeteria-feeding trials. Winter habitat on Anticosti is degraded and free-ranging deer at high densities consume 70% balsam fir (Abies balsamea) and 20% white spruce (Picea glauca), even though spruce is much more available than fir. Deer ate 89.9% balsam fir and 10.1% white spruce when the availability of both trees was equal. Deer did not eat shredded twigs more than intact twigs. Fiber content and condensed tannins were greater in white spruce than in balsam fir. Deer preference for fir was not based on texture but, more likely, on plant constituents, so we concluded that deer will nearly eliminate fir before they use any significant amount of white spruce. Management actions, therefore, need to be undertaken to enhance balsam fir regeneration. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Zoology is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Habitat-selection analysis involves a comparison between the proportions of different cover types that are used by the animal and the proportions that are available. Telemetry locations or animal occurrences (e.g., from aerial surveys) can provide information on habitat utilization. With telemetry data, a classical approach involves computing habitat use at the individual location sites or inside fixed circle buffers applied to the sites. We used this approach (200 m radius circles) on data from a systematic aerial survey on Anticosti Island, where 260 groups of white-tailed deer (Odocoileus virginianus) (374 animals) were counted in a 270-km² block. We compared the selection indices obtained from site occurrences with those of two approaches that define areas of high intensity (animal concentrations): 50% fixed kernels (0.5-2 km bandwidth) and the local K function (0.5-2 km distance). The results were very consistent among the three sets of approaches, with the same cover types generally identified as those having the highest or lowest indices. White-tailed deer preferred forest stands where balsam fir (Abies balsamea) was present as high regeneration or was dominant in the tree layer (>50% basal area) and stands at the regeneration stage. In the studied landscape, there seems to be a wide range of spatial scales where the selection process can be analyzed from aerial survey data. [ABSTRACT FROM AUTHOR]

Presents a study that tested the double-count technique for White-Tailed Deer on Anticosti Island and in different areas on the Québec mainland. Precision and repeatability of the density estimates under different conditions; Comparison of deer number estimates and costs with the pellet-group count; Implications for deer population management.

Cylindrical tubes of the trace fossil Chaetosalpinx occur within the skeletal walls of Late Ordovician sarcinulid tabulate corals preserved on Anticosti Island. A large host-specific embedment structure, Chaetosalpinx rex isp. nov., is described from the reefal sarcinulid genus Columnopora that occurs in (Rawtheyan, Ashgill) coral-stromatoporoid patch reefs of the upper Vauréal Formation (Mill Bay Member). While locally abundant in Columnopora, this newly described embedment structure is absent in other framebuilders in the reefs. [ABSTRACT FROM AUTHOR]

Six modifications to the hinge occur in strophomenoid brachiopods from Anticosti Island: (1) overhanging socket ridges; (2) posterolateral socket ridges along the interarea articulate with grooves on the posterior of teeth; (3) anteromedian dental notches articulate with the crests of socket ridges; (4) dental crenulations on the surfaces of teeth mesh with socket ridges; (5) denticles extend laterally to the cardinal extremities; and (6) the margin of the ventral interarea fits into a long socket along the dorsal interarea forming a lateral tooth. Denticulate hinges and dental notches that typify Silurian and Devonian strophomenids begin in the fauna of the Ellis Bay Formation. Thus the most important interval of strophomenid faunal turnover was at the base of the Gamachian (the base of the Hirnantian) and not at the Ordovician–Silurian boundary. Muscle attachment pads in the delthyrial cavity do not correspond to the positions of either the adductor or diductor muscle scars. Pedicle adjustor muscles in modern brachiopods occupy this position. The round gap between the median fold of the pseudodeltidium and groove on chilidium is proposed as the point of emergence of the pedicle muscle. The tiny foramen, commonly sealed early in growth, is suggested to be part of a neanic water-intake system, active before the growth of the cardinal process in ephebic shells. Once the cardinal process appeared, the foramen was blocked. Recurring types of strophomenid ornamentation, such as posteriorly steepened rugae and checkerboard ornamentation, may have served as a plow to redistribute sediment as the shell was pulled backwards along the pedicle.Six modifications de la charnière sont présentes dans les Brachiopodes strophoménoïdés de l'Île d'Anticosti: (1) la présence de crêtes fossulaires surplombantes, (2) les crêtes fossulaires postéro-latérales le long de l'interaréa sont articulées avec des rainures sur la partie postérieure des dents, (3) des échancrures antéro-médianes s'articulent avec les crêtes fossulaires, (4) des crénulations sur la surface des dents s'engrènent avec les crêtes fossulaires, (5) des denticules sont présentes latéralement jusqu'aux extrémités cardinales et (6) la marge de l'interaréa ventral s'insère dans une longue fossette le long de l'interaréa dorsal, formant une dent latérale. Les charnières denticulées et les échancrures dentales typiques des strophoménidés du Silurien et du Dévonien débutent dans la faune de la Formation d'Ellis Bay. Ainsi, le changement faunique le plus important des strophoménidés se situe à la base du Gamachien (base de l'Hirnantien) et non pas à la limite Ordovicien–Silurien. Les cicatrices des muscles dans la cavité delthyriale ne correspondent pas aux positions des muscles adducteurs ou diducteurs. Les muscles ajusteurs pédonculaires occupent cet endroit dans les Brachiopodes modernes. Le trou rond entre le pli médian du pseudodeltidium et le sillon sur le chillidium est proposé comme point d'émergence du muscle pédonculaire. Le petit foramen, généralement calfaté pendant la croissance précoce, est suggéré comme faisant partie du système néanique d'inspiration d'eau, fonctionnel avant la croissance du processus cardinal dans les coquilles éphébiques. Une fois le processus cardinal apparu, le foramen était bouché. Certains types périodiques d'ornementation de strophoménidés, tels les rugae postérieurement plus abruptes et l'ornementation en damier, auraient pu servir de charrue pour redistribuer les sédiments quand la coquille était tirée vers l'arrière le long du pédoncule.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]