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2. Winter habitat selection by white-tailed deer on Anticosti Island 2: relationship between deer density from an aerial survey and the proportion of balsam fir forest on vegetation maps.
- Author
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Potvin, François and Boots, Barry
- Subjects
DEER wintering ,ODOCOILEUS ,BALSAM fir ,FORESTS & forestry - Abstract
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.)
- Published
- 2004
- Full Text
- View/download PDF
3. Comparison among three approaches to evaluate winter habitat selection by white-tailed deer on Anticosti Island using occurrences from an aerial survey and forest vegetation maps.
- Author
-
Potvin, François, Boots, Barry, and Dempster, Alastair
- Subjects
WHITE-tailed deer ,HABITATS ,BALSAM fir ,FIR - Abstract
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]
- Published
- 2003
- Full Text
- View/download PDF
4. Hinge modifications and musculature of strophomenoid brachiopods: examples across the Ordovician-Silurian boundary, Anticosti Island, Quebec.
- Author
-
Dewing, Keith
- Subjects
ORDOVICIAN paleoecology ,ORDOVICIAN stratigraphic geology ,PALEOZOIC paleoecology ,ISLANDS - Abstract
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]
- Published
- 2001
- Full Text
- View/download PDF
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