PREDATION BY INSECTS AND SPIDERS INHABITING COLONIAL WEBS OF HYPHANTRIA CUNEA

1972 ◽  
Vol 104 (8) ◽  
pp. 1197-1207 ◽  
Author(s):  
R. F. Morris

AbstractThe number of predators inhabiting nests of Hyphantria cunea Drury was recorded annually for 13 years in four areas in New Brunswick and two areas on the coast of Nova Scotia. The most common groups were the pentatomids and spiders, which sometimes reproduced within the nests, but the mean number per nest was low in relation to the number of H. cunea larvae in the colonies. The rate of predation on fifth-instar larvae was low. Small or timid predators appeared to prey largely on moribund larvae or small saprophagans during the principal defoliating instars of H. cunea.No relationship could be detected between the number of larvae reaching the fifth instar and the number of predators in the colony; nor could any functional or numerical response of the predators to either the initial number of larvae per colony or the population density of colonies be found. It is concluded that the influence of the nest-inhabiting predators is small and relatively stable, and may be treated as a constant in the development of models to explain the population dynamics of H. cunea.H. cunea is a pest in parts of Europe and Asia, where it has been accidentally introduced from North America. The introduction to other continents of the North American predator, Podisus maculiventiis (Say), is discussed briefly.

1976 ◽  
Vol 108 (7) ◽  
pp. 685-687 ◽  
Author(s):  
R. F. Morris

AbstractFour of the parasite species attacking Hyphantria cunea Drury spin their cocoons inside the colonial web of the host, where they are exposed to attack by five species of hyperparasites. Percentage hyperparasitism was measured over a 15-year period in permanent study areas in New Brunswick and Nova Scotia. The mean percentage was about 50%, with very wide variations from year to year. These variations were not related to the population density of H. cunea or its parasites and no model for hyperparasite-parasite interaction could be constructed.


1981 ◽  
Vol 113 (12) ◽  
pp. 1123-1124 ◽  
Author(s):  
W. B. Preston ◽  
A. R. Westwood

The spread of Thymelicus lineola (Ochsenheimer) in North America has been extensively documented (Rawson 1931; Clench 1956; Pengelly 1961; Arthur 1966; Burns 1966; McNeil et al. 1975; McNeil and Duchesne 1977). In Canada, T. lineola has been recorded from British Columbia, Ontario, Quebec, New Brunswick, Nova Scotia, Newfoundland, and now Manitoba (Gregory 1975; Jackson 1978). In the north central United States T. lineola has been recorded from St. Louis Co. and International Falls, Minnesota (Brewer 1977; Lundeen 1980). Pengelly (pers. comm.) observed T. lineola at Dryden, Ontario in 1972. McCabe and Post (1977) did not include this species in their list for North Dakota. The purpose of the present note is to report on the presence and collections of T. lineola in Manitoba and in northwestern Ontario.


2021 ◽  
pp. 1-20
Author(s):  
Pedro Cózar ◽  
Ian D. Somerville

Abstract In this study, middle to late Mississippian microfossil assemblages from the Maritimes Basin of eastern Canada (Nova Scotia, SW Newfoundland, and New Brunswick) are closely compared to those from Western Paleotethys basins. The comparison is focused mainly on foraminifers and calcareous algae. Most foraminifers and algae described from the Maritimes Basin are considered cosmopolitan, and the occurrence in western Europe and northern Africa of taxa previously considered endemic to the North America Realm suggests a close paleobiogeographic relationship. This European/African correlation is further supported by other foraminiferal/algal taxa, the importance of which were previously overlooked, including: Plectogyranopsis ex gr. P. hirosei (Okimura, 1965), Mikhailovella Ganelina, 1956, Koktjubina windsorensis (Mamet, 1970), Polysphaerinella bulla Mamet, 1973, Mstinia Dain in Dain and Grozdilova, 1953, Haplophragmina Reitlinger, 1950, Omphalotis Shlykova, 1969, Pseudolituotuba Vdovenko, 1971, Pseudoendothyra Mikhailov, 1939, Saccamminopsis (Sollas, 1921) Vachard and Cózar, 2003, Kamaenella Mamet and Roux, 1974, and Anthracoporellopsis Maslov, 1956. Some species recorded in the Maritimes Basin have been typically recorded in Britain and Ireland in the southern platform of Laurussia. This implies a connection via the Rhenohercynian Ocean, whereas statistical analyses suggest that Maritimes Basin assemblages are closer to those of the Gondwana platform, which could have been established via the Paleotethys Ocean, and also with terranes northwest of the Variscan Front, in which its most logical connection should be with a still-open Rheic Ocean during the Visean and early Serpukhovian. Those taxa demonstrate a more-or-less continuous faunal and microfloral interchange between the Maritimes Basin and the Western Paleotethys paleobiogeographic realm. Furthermore, the width of the Paleotethys and Rheic oceans separating these regions is not considered excessive, particularly during the late Visean and early Serpukhovian.


1976 ◽  
Vol 108 (11) ◽  
pp. 1291-1294 ◽  
Author(s):  
R. F. Morris

AbstractParasitism in natural populations of Hyphantria cunea Drury was measured in New Brunswick and Nova Scotia, 1957–1973. Thirteen parasite species were recovered during this period but only a few caused an appreciable degree of mortality. The per cent mortality showed an immediate rather than a delayed response to host density, the relationship being direct up to a density of about 10 host colonies per mile, then inverse. Possible reasons for this sort of relationship are discussed.


Author(s):  

Abstract A new distribution map is provided for Chrysomyxa arctostaphyli Dietel Fungi: Basidiomycota: Uredinales Hosts: Picea spp. and Arctostaphylos uva-ursi. Information is given on the geographical distribution in NORTH AMERICA, Canada, Alberta, British Columbia, Manitoba, New Brunswick, Newfoundland, Northwest, Territories, Nova Scotia, Ontario, Quebec, Saskatchewan, Yukon, USA, Alaska, Arizona, Colorado, Idaho, Maine, Michigan, Montana, New Mexico, New York, Oregon, South Dakota, Utah, Washington, Wisconsin, Wyoming.


1977 ◽  
Vol 28 (4) ◽  
pp. 417 ◽  
Author(s):  
R Marchant ◽  
WD Williams

Quantitative samples of P. zietziana were taken monthly for two years from Pink Lake and Lake Cundare. Shrimps were usually contagiously distributed. To reduce error, samples were stratified resulting in confidence limits of 40-50% for the mean population density. Despite this variability, stable trends emerged, and variation was not so great as to mask significant differences. Length-frequency analyses distinguished cohorts; a regression was established between length and dry weight, enabling growth to be estimated from samples. By combining growth with population densities in Allen curves, production was computed. In Pink Lake and Lake Cundare mean pro- duction was 11.3 and 1.0 g dry weight m-2 year-1 respectively. Generally there were two or three generations per year, but time and extent of recruitment were not predictable. Each generation suffered continuous mortality, the death of young shrimps accounting for most of the production. This mortality remains unexplained; there are no significant predators and salinity and temperature stress would occur only during summer.


2000 ◽  
Vol 74 (5) ◽  
pp. 858-878 ◽  
Author(s):  
Stephen R. Westrop ◽  
Ed Landing

The Hanford Brook Formation, one of the classic Cambrian units of Avalonian North America, contains at least eight species of endemic trilobites, including Berabichia milleri Westrop n. sp., that are assigned to seven genera. The vertical succession of faunas is far more complex than has been recognized previously, with each member containing a lithofacies-specific assemblage. These are, in ascending order: a bradoriid-linguloid Association without trilobites in the nearshore St. Martin's Member, a Protolenus Association in dysaerobic siltstones and sandstones of the Somerset Street Member, and a Kingaspidoides-Berabichia Association in hummocky cross-stratified sandstones of the Long Island Member that overlie a parasequence boundary at Hanford Brook. Due to the breakdown of biogeographic barriers in the late Early Cambrian, two new species-based zones, the Protolenus elegans and Kingaspidoides cf. obliquoculatus zones, share trilobite genera with the Tissafinian Stage of Morocco. This generic similarity has been the basis for correlation of this upper Lower Cambrian interval on the Avalon continent with the West Gondwanan lowest Middle Cambrian. However, the clear facies control on the occurrence of genera in the Hanford Brook Formation and the presence of an abrupt faunal break and unconformity at the base of the Tissafinian in Morocco makes this correlation questionable. The Hanford Brook Formation may represent a late Early Cambrian interval unknown in Gondwana. Sequence-stratigraphic criteria even raise the possibility that the Protolenus Association is the biofacies equivalent of Callavia broeggeri Zone faunas of the Brigus Formation of Newfoundland, Nova Scotia and Massachusetts.


Author(s):  
Faye Margaret Kert

This journal examines privateering and naval prizes in Atlantic Canada in the maritime War of 1812 - considered the final major international manifestation of the practice. It seeks to contextualise the role of privateering in the nineteenth century; determine the causes of, and reactions to, the War of 1812; determine the legal evolution of prize law in North America; discuss the privateers of Nova Scotia and New Brunswick, and the methods they utilised to manipulate the rules of prize making during the war; and consider the economic impact of the war of maritime communities. Ultimately, the purpose of the journal is to examine privateering as an occupation in order to redeem its historically negative reputation. The volume is presented as six chapters, plus a conclusion appraising privateering, and seven appendices containing court details, prize listings, and relevant letters of agency.


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