Jurassic quartz-normative tholeiite dikes from Anticosti Island, Quebec

1992 ◽  
pp. 161-168 ◽  
Author(s):  
Jean H. Bédard
Keyword(s):  
Anticosti Island

A test of the predator avoidance hypothesis to explain delayed onset of communal breeding

2019 ◽  
Vol 97 (4) ◽  
pp. 332-339
Author(s):  
D. Strickland ◽  
E. Brouwer ◽  
T.M. Burg
Keyword(s):  
Predator Avoidance ◽  
Group Living ◽  
Breeding Cycle ◽  
Communal Breeding ◽  
The Family ◽  
Perisoreus Canadensis ◽  
Insufficient Time ◽  
Anticosti Island ◽  
Free Environment ◽  
Late Stages

A neglected question in the study of communal breeding concerns why alloparental behaviour begins at variously late stages in the breeding cycle. In group-living corvids, the delay tends to be longer in species that are small and (or) typically have only a small nonbreeder complement. This pattern has been attributed to the relatively poor defensive capabilities of such species and their consequently greater need to minimize predator-attracting traffic to the nest or fledglings. We tested this predator avoidance hypothesis with the Canada Jay (Perisoreus canadensis (Linnaeus, 1766)), a species in which the feeding of young by any nonbreeders in the family group is delayed until the fledgling period. We reasoned that, on Anticosti Island, Quebec (Canada), in the absence of squirrels and other nest predators, nonbreeders might be permitted to feed nestlings as well as fledglings, and that breeders might feed nestlings more frequently (with smaller food loads) than on the mainland. We found no evidence for either prediction and thus no support for the predator avoidance hypothesis but suggest that Anticosti Canada Jays may have had insufficient time to evolve behaviour more appropriate for their predator-free environment. Secondarily, we confirmed that in all observed instances, the nonbreeders were offspring of the breeding pair from previous years and that they therefore failed to provision nestlings in spite of an apparent genetic interest to do so.

Impact of deer browsing on plant communities in cutover sites on Anticosti Island

Ecoscience ◽  
2008 ◽  
Vol 15 (3) ◽  
pp. 389-397 ◽  
Author(s):  
Christine Casabon ◽  
David Pothier
Keyword(s):  
Plant Communities ◽  
Deer Browsing ◽  
Anticosti Island

Maturation thermique et histoire de l'enfouissement et de la génération des hydrocarbures du bassin de l'archipel de Mingan et de l'île d'Anticosti, Canada

1990 ◽  
Vol 27 (6) ◽  
pp. 731-741 ◽  
Author(s):  
Rudolf Bertrand
Keyword(s):  
Carbonate Platform ◽  
Burial History ◽  
Upper Ordovician ◽  
Southeastern Part ◽  
Middle Ordovician ◽  
Oil Generation ◽  
Wide Range ◽  
History Of ◽  
Anticosti Island ◽  
Depth Of Burial

Carbonate platform sequences of Anticosti Island and the Mingan Archipelago are Early Ordovician to Early Silurian in age. With the exception of the Macasty Formation, the sequences are impoverished in dispersed organic matter, which is chiefly composed of zooclasts. Zooclast reflectances suggest that the Upper Ordovician and Silurian sequences outcropping on Anticosti Island are entirely in the oil window but that the Lower to Middle Ordovician beds of the Mingan Archipelago and their stratigraphic equivalents in the subsurface of most of Anticosti Island belong to the condensate zone. Only the deeper sequences of the southwestern sector of Anticosti Island are in the diagenetic dry-gas zone. The maximum depth of burial of sequences below now-eroded Silurian to Devonian strata increases from 2.3 km on southwestern Anticosti Island to 4.5 km in the Mingan Archipelago. A late upwarp of the Precambrian basement likely allowed deeper erosion of the Paleozoic strata in the vicinity of the Mingan Archipelago than on Anticosti Island. Differential erosion resulted in a southwestern tilting of equal maturation surfaces. The Macasty Formation, the only source rock of the basin (total organic carbon generally > 3.5%, shows a wide range of thermal maturation levels (potential oil window to diagenetic dry gas). It can be inferred from the burial history of Anticosti Island sequences that oil generation began later but continued for a longer period of geologic time in the northeastern part than in the southeastern part of the island. Oil generation was entirely pre-Acadian in the southern and western parts of Anticosti Island, but pre- and post-Acadian in the northern and eastern parts.

Upper Ordovician ostracods from the Cautley district, northern England: Baltic and Laurentian affinities

2001 ◽  
Vol 138 (5) ◽  
pp. 589-607 ◽  
Author(s):  
MARK WILLIAMS ◽  
PHILIP STONE ◽  
DAVID J. SIVETER ◽  
PAULINE TAYLOR
Keyword(s):  
North America ◽  
Significant Extent ◽  
Baltic Region ◽  
Upper Ordovician ◽  
Northern Germany ◽  
Iapetus Ocean ◽  
Windermere Supergroup ◽  
Distributional Patterns ◽  
Anticosti Island ◽  
The Baltic

The Cautley Mudstone Formation and Cystoid Limestone Member of the Ashgill Formation (Windermere Supergroup; Ashgill Series), from the Cautley district of northern England, has yielded an ostracod fauna of more than 30 species. Many of these have short ranges, permitting recognition of stratigraphically successive Pusgillian–lower Cautleyan, middle–upper Cautleyan, and Rawtheyan ostracod faunas. Several species are also known from the upper Ordovician of North America (Anticosti Island), Scotland (Girvan district) and the Baltic region (Estonia, glacial erratic boulders of northern Germany), providing evidence to correlate upper Ordovician successions in these areas. The ostracods include abundant podocopes, at some horizons accounting for more than 80% of the fauna. Binodicopes are also common, but palaeocopes are rare. Assemblages are typical of a clastic dominated open marine shelf setting. Diversity at most horizons is low (c. 3–5 species), but reaches a peak of between 13–14 species in middle Cautleyan horizons. Lower diversity at Pusgillian and Rawtheyan horizons coincides with the encroachment of deeper marine-shelf facies which were probably hostile to Ordovician benthonic ostracods. Some of the ostracods (particularly Aechmina) have distributions suggesting tolerance of a range of mid- to deep shelf benthonic palaeoenvironments, but none were pelagic. During Ashgill times the Cautley district (part of palaeocontinental Avalonia) was replete with ostracod genera and species which also occur in the Baltic region (palaeocontinental Baltica; more than 90% generic similarity) and to a lesser, but nonetheless significant extent in North America and Scotland (parts of palaeocontinental Laurentia). Such trans-Tornquist Sea and Iapetus Ocean distributional patterns add to previous ostracod data that support models which show palaeogeographical proximity of Avalonia and Baltica, and Avalonia and Laurentia, by Ashgill times. The widely cited observation, that trans-Iapetus ostracod faunas remained strictly provincial until the mid-or late Silurian, cannot be sustained.

Geology of the Central Part of Anticosti Island, Quebec

1975 ◽  
Author(s):  
M J Copeland ◽  
T E Bolton
Keyword(s):  
Anticosti Island

Pup production and population trends of the grey seal (Halichoerus grypus) in the Gulf of St. Lawrence

1998 ◽  
Vol 55 (2) ◽  
pp. 423-430 ◽  
Author(s):  
M O Hammill ◽  
G B Stenson ◽  
R A Myers ◽  
W T Stobo
Keyword(s):  
Population Trends ◽  
Annual Rate ◽  
Halichoerus Grypus ◽  
Grey Seal ◽  
Northwest Atlantic ◽  
Mark Recapture ◽  
Seal Population ◽  
Independent Estimate ◽  
Anticosti Island

Grey seal (Halichoerus grypus) pup production of the Gulf of St. Lawrence component of the Northwest Atlantic grey seal population was determined for the 1984-1986 and 1989-1990 periods using mark-recapture methods. Pup production estimates based on recaptures from shot samples from Anticosti Island ranged from 5436 (SE = 672) to 6955 (SE = 1183) for 1984-1986. An independent estimate for 1984-1986, based on animals captured on Sable Island, was 7431 (SE = 1414) to 8633 (SE = 2827). Mark-recapture estimates of pup production for 1989 and 1990 from shot samples collected from Anticosti Island were 8825 (SE = 3164) and 9156 (SE = 2652), respectively. The estimates based on animals captured on Sable Island varied from 7295 (SE = 2118) to 8116 (SE = 846) for 1989-1990. Both the Anticosti Island and Sable Island recovery samples underestimate 1989 pup production due to hunting which removed 1612 pups from the population before they could disperse. The Gulf component of the Northwest Atlantic grey seal population is increasing at an annual rate of 7.4% (SE = 2.2).

Sign in / Sign up

Export Citation Format

Share Document