Sexual reproduction and larval development of Rhaphidrilus nemasoma Monticelli, 1910 (Polychaeta: Ctenodrilidae)

1989 ◽  
Vol 67 (10) ◽  
pp. 2345-2351 ◽  
Author(s):  
Pei-Yuan Qian ◽  
Fu-Shiang Chia
Keyword(s):  
British Columbia ◽  
Sexual Reproduction ◽  
Larval Development ◽  
Intertidal Zone ◽  
Vancouver Island ◽  
Benthic Diatoms ◽  
Egg Mass ◽  
High Fecundity ◽  
Egg Masses ◽  
Trochophore Stage

Adult specimens and egg masses of Rhaphidrilus nemasoma were collected in the low intertidal zone from Execution Rock, Bamfield, Vancouver Island, British Columbia, in June of 1986. Each egg mass contained about 1000 eggs. The eggs were green, spherical, and measured 125–145 μm in diameter. Larval development took place within the egg mass until the three-or four-setiger stage, at which time they emerged from the egg mass. Newly emerged larvae crawled on the bottom of the culture beakers and fed on benthic diatoms. Metamorphosis took place soon after emergence and was completed within 2 weeks. Paddle cilia were observed at the early trochophore stage, and their possible function, and the extremely high fecundity of this polychaete, are discussed.

Micronereis nanaimoensis sp. n.: with some Notes on its Life-History

1953 ◽  
Vol 10 (2) ◽  
pp. 85-95 ◽  
Author(s):  
E. Berkeley ◽  
C. Berkeley
Keyword(s):  
British Columbia ◽  
Life History ◽  
Larval Development ◽  
Cold Water ◽  
Egg Laying ◽  
Egg Mass ◽  
Free Swimming ◽  
Definition Of

Micronereis nanaimoensis sp. n. is described from the region of Nanaimo, British Columbia. The definition of Micronereis is slightly emended to include the species. It differs from its only congener, M. variegata Claparède of Europe, in being much larger, in possessing palps, in having more varied setae and different specialized crotchets in the males, and in colour. Swarming, pairing and egg-laying occur from late March to the end of May. The eggs are moulded by the female into masses covered by jelly, which are deposited on leaves of Zostera, Ulva, or other seaweeds, near low-tide mark, and are accompanied by her in the jelly until the larvae become free-swimming. In the laboratory, larvae left the egg-mass after 10–16 days, in cold water. Larval development up to the three-segmented stage is illustrated, and supports the inclusion of Micronereis in Nereidae.

Observations on the behavior and larval development of Acanthomysis sculpta (Tattersall), (Mysidacea)

1970 ◽  
Vol 48 (2) ◽  
pp. 289-292 ◽  
Author(s):  
John M. Green
Keyword(s):  
British Columbia ◽  
Larval Development ◽  
Vancouver Island ◽  
Brood Pouch ◽  
Plastic Trays

Observations on the behavior and larval development of A. sculpta collected from a surge channel at Botanical Beach, Vancouver Island, British Columbia, were made from 12 to 25 August, 1965. Larvae-bearing females were kept in compartmented plastic trays and larvae from their brood pouches were periodically removed and preserved. Development from hatching to liberation from the brood pouch takes about 5 days at about 12 °C. Apparently, the young are liberated from the brood pouch only at night. The nocturnal emergence of the young is considered to be important to their survival in that it helps prevent them from being eaten by larger specimens.

The plainfin midshipman’s soundscape at two sites around Vancouver Island, British Columbia

2018 ◽  
Vol 603 ◽  
pp. 189-200 ◽  
Author(s):  
WD Halliday ◽  
MK Pine ◽  
APH Bose ◽  
S Balshine ◽  
F Juanes
Keyword(s):  
British Columbia ◽  
Vancouver Island

Ecotypic variation affects the conservation of North American badgers endangered along their northern range extent

2018 ◽  
Author(s):  
Richard D. Weir ◽  
Trevor A. Kinley ◽  
Richard W. Klafki ◽  
Clayton D. Apps
Keyword(s):  
British Columbia ◽  
Cause Of Death ◽  
Conservation Strategies ◽  
High Fecundity ◽  
Ecological Information ◽  
The Core ◽  
Ecotypic Variation ◽  
Sufficient Energy ◽  
Soil Deposits ◽  
Regional Conservation

This chapter is based on ecological information on 82 radio-tagged badgers (39 F, 43 M) among three study populations in British Columbia, Canada between 1996 and 2010, data that were collected to learn more about the ecology of badgers and consider how variation in their ecology might inform regional conservation strategies. The widely spaced, lower density prey and distribution of soil deposits suitable for digging in British Columbia likely required badgers to use substantially larger areas, relative to the core range, in which to acquire sufficient energy to survive and reproduce. Strikes from automobiles were the primary cause of death among all radio-tagged badgers and this source of mortality is pervasive throughout the limited distribution of badgers in British Columbia. Despite their potential for high fecundity, populations of badgers in British Columbia likely remain at considerable risk compared to those in the core of the species’ range.

scholarly journals New terpenoid metabolites from the skin extracts, an egg mass, and dietary sponges of the Northeastern Pacific dorid nudibranch Cadlinaluteomarginata

1997 ◽  
Vol 75 (6) ◽  
pp. 773-789 ◽  
Author(s):  
Eric J. Dumdei ◽  
Julia Kubanek ◽  
John E. Coleman ◽  
Jana Pika ◽  
Raymond J. Andersen ◽  
...  
Keyword(s):  
Structure Elucidation ◽  
Egg Mass ◽  
The Novel ◽  
Egg Masses ◽  
Northeastern Pacific ◽  
First Time

Chemical investigations of Cadlinaluteomarginata skin extracts, egg masses, and dietary sponges have led to the identification of the novel terpenoids cadlinaldehyde (30), spongian 32, seco-spongian 35, 20-acetoxy-12-marginatone (38), and lutenolide (39) from the nudibranch skin extracts, the new drimane sesquiterpenoid 1α,2α-diacetoxyalbicanyl acetate (40) from the nudibranch's egg mass, and the new sesquiterpenoids O-methyl-9-oxofurodysininlactone (47), 2-oxomicro-cionin-2-lactone (48), and O-methyl-2-oxomicrocionin-2-lactone (49), from the dietary sponge Pleraplysilla sp. The known terpenoids furodysinin (1), furodysin (16), marginatafuran (21), and 9,11-dihydrogracillin A (37), which have been frequently isolated from C. luteomarginata skin extracts, were found for the first time in extracts of the dietary sponges Pleraplysilla sp. and Aplysilla sp. One of the new terpenoids, cadlinaldehyde (30), has an unprecedented degraded sesterterpenoid skeleton. Keywords: nudibranch, sponge, terpenoids, structure elucidation.

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.

scholarly journals A rare genotype of Cryptococcus gattii caused the cryptococcosis outbreak on Vancouver Island (British Columbia, Canada)

2004 ◽  
Vol 101 (49) ◽  
pp. 17258-17263 ◽  
Author(s):  
S. E. Kidd ◽  
F. Hagen ◽  
R. L. Tscharke ◽  
M. Huynh ◽  
K. H. Bartlett ◽  
...  
Keyword(s):  
British Columbia ◽  
Vancouver Island ◽  
Cryptococcus Gattii
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