scholarly journals First Records of Long-beaked Common Dolphins, Delphinus capensis, in Canadian Waters

2005 ◽  
Vol 119 (1) ◽  
pp. 110 ◽  
Author(s):  
John K. B. Ford
Keyword(s):  
British Columbia ◽  
Warm Water ◽  
Common Dolphin ◽  
Central California ◽  
Far North ◽  
Common Dolphins ◽  
Delphinus Capensis

The genus Delphinus has recently been determined to be comprised of two species, the Short-beaked Common Dolphin, D. delphis, and the Long-beaked Common Dolphin, D. capensis. D. delphis is regularly observed in eastern Canadian waters, but is known only from a single stranding in British Columbia. Two specimen records and a series of sightings of D. capensis in British Columbian waters during 1993-2003, detailed here, are the first for this species in Canada. D. capensis normally ranges only as far north as central California, and its abundance in those waters increases in association with warm-water oceanographic events. Although the species appears to be rare in British Columbia, future sightings during warm-water periods might be anticipated.

Identification and significance of late Holocene tephra from Otter Creek, southern British Columbia, and localities in west-central Alberta

1977 ◽  
Vol 14 (11) ◽  
pp. 2593-2600 ◽  
Author(s):  
J. A. Westgate
Keyword(s):  
British Columbia ◽  
Late Holocene ◽  
Far North ◽  
West Central ◽  
Tephra Beds ◽  
Middle Unit ◽  
Mount St Helens

Three thin, light-coloured, ash-grade tephra beds occur within the uppermost metre of peat at Otter Creek bog in southern British Columbia. The youngest tephra is related to the ~2600 year old Bridge River tephra but is probably the product of a younger and weaker eruption that directed tephra to the southeast of the vent, believed to be located in the Meager Mountain district of southwestern British Columbia. The middle unit is ~2100 years old and is tentatively correlated with one of the upper beds of set P tephra of Mount St. Helens in Washington. The lowermost tephra is equivalent to the Yn bed of set Y, derived from an eruption of Mount St. Helens about 3400 years ago.The Yn tephra has been located as far north as Entwistle in west-central Alberta but mineralogically and chemically similar tephra elsewhere in this region is ~4300 years old and thus represents an older part of the Y set. Significant compositional differences between these two extensive members of the Y set have not yet been recognized.

scholarly journals Conservation Evaluation of the Small-flowered Tonella, Tonella tenella, in Canada

2006 ◽  
Vol 120 (2) ◽  
pp. 179
Author(s):  
George W. Douglas ◽  
Jenifer L. Penny
Keyword(s):  
British Columbia ◽  
Private Property ◽  
Columbia River ◽  
The West ◽  
Rock Outcrops ◽  
West Side ◽  
Central California ◽  
Gulf Islands ◽  
Talus Slopes ◽  
Conservation Evaluation

In Canada, the Small-flowered Tonella, Tonella tenella, is restricted to the west side of Saltspring Island in the Gulf Islands of southwestern British Columbia. This population represents the northern limits of the species which is disjunct from its main range in southern Washington (Columbia River gorge), through Oregon to central California. In British Columbia, Tonella tenella is associated with rock outcrops and dry, steep, sparsely forested talus slopes at elevations of 50 to 300 m. The population on Saltspring Island is on private property and not directly imperilled at this time. There is, however, a potential for housing development in the future on this waterfront site, thus the authors consider the species endangered.

THE STAGES OF ERANNIS VANCOUVERENSIS (LEPIDOPTERA: GEOMETRIDAE) AND LIFE HISTORY NOTES

1973 ◽  
Vol 105 (4) ◽  
pp. 605-612 ◽  
Author(s):  
David Evans
Keyword(s):  
British Columbia ◽  
Life History ◽  
Virus Disease ◽  
Pupal Stage ◽  
Early Spring ◽  
Deciduous Trees ◽  
Life Stages ◽  
Larval Instars ◽  
Central California ◽  
Young Leaves

AbstractErannis vancouverensis Hulst occurs from northern British Columbia to central California, and has been occasionally reported at infestation levels. The larvae feed on young leaves of several species of deciduous trees; winter is passed in the egg or sometimes in the pupal stage; adults emerge during late autumn or occasionally during winter or early spring; females are wingless. The life stages, including larval instars, are described here in detail. Virus disease and parasitism by tachinid flies help control the species.

scholarly journals Cetaceans using the marine protected area of "Parque Estadual Marinho da Laje de Santos", Southeastern Brazil

2017 ◽  
Vol 65 (4) ◽  
pp. 605-613 ◽  
Author(s):  
Marcos Cesar de Oliveira Santos ◽  
Giovanna Corrêa e Figueiredo ◽  
Marie-Francoise Van Bressem
Keyword(s):  
Protected Area ◽  
Marine Protected Area ◽  
Unknown Origin ◽  
Mantel Test ◽  
Southeastern Brazil ◽  
Common Dolphin ◽  
Balaenoptera Acutorostrata ◽  
Stenella Frontalis ◽  
Delphinus Delphis ◽  
Common Dolphins

Abstract The aim of this study was to evaluate the presence of cetaceans in the waters surrounding the Marine Protected Area (MPA) known as “Parque Estadual Marinho da Laje de Santos (PEMLS)”, placed in coastal waters at the southeastern coast of Brazil. Boat-based surveys were conducted once a month from June 2013 to June 2015. A specific transect was followed to cover the area of the quoted MPA, as well as its borders. A total of 24 boat-surveys rendered 18 sightings of cetacean groups of the following species: Atlantic spotted dolphin (Stenella frontalis) (12), rough-toothed dolphin (Steno bredanensis) (2), common dolphin (Delphinus delphis) (1), Bryde’s whale (Balaenoptera edeni) (2) and common minke whale (Balaenoptera acutorostrata) (1). Sightings of S. frontalis, the commonest sighted species, was positively correlated with water depth (Mantel test; r = 0.8072; p < 0.05). Photoidentified individuals moved back and forth to inner and outer areas of the MPA, remaining in the area throughout the 2-year survey. “Paisley” cutaneous marks of unknown origin were reported in two common dolphins for the first time in local waters. As the PEMLS has been used as an important spot for SCUBA divers, it is recommended that cetacean sightings could still be gathered in a future partnership, as well as using the acoustics tool to detect their presence when researchers are not in the field.

An Explanation for the Warmwater Intrusion off the British Columbia Coast

1972 ◽  
Vol 29 (1) ◽  
pp. 103-107 ◽  
Author(s):  
Richard E. Thomson
Keyword(s):  
British Columbia ◽  
Characteristic Feature ◽  
Direct Effect ◽  
Wind Stress ◽  
Stress Component ◽  
Meridional Wind ◽  
Warm Water ◽  
Ekman Transport ◽  
Temperature Variations ◽  
Annual Variations

An explanation is given for the well-known annual variations in the northward penetration of relatively warm water off the British Columbia coast. At the top of the permanent halocline, a characteristic feature of the region, both the onshore Ekman transport, resulting from a northward meridional wind-stress component, and the relative warmth of the upper oceanic layer in winter are suggested as being responsible for these variations. At the bottom of the halocline, which lies below the depth of direct surface influence, comparison of the northward meridional wind-stress component with the temperature variations suggests that other processes besides the direct effect of Ekman transport are important in determining the variations at that level.

scholarly journals Short-term effects of tourism on the behaviour of common dolphins (Delphinus delphis) in the Azores

2017 ◽  
Vol 98 (5) ◽  
pp. 1187-1196 ◽  
Author(s):  
Arianna Cecchetti ◽  
Karen A. Stockin ◽  
Jonathan Gordon ◽  
José M.N. Azevedo
Keyword(s):  
Transition Probabilities ◽  
High Energy ◽  
Tourism Industry ◽  
Common Dolphin ◽  
Short Term ◽  
Delphinus Delphis ◽  
Critical Activity ◽  
Time Required ◽  
Common Dolphins

Short-term measures of behavioural responses of cetaceans to tourism operations have been used in many studies to interpret and understand potential long-term impacts of biological importance. The short-beaked common dolphin (Delphinus delphis) is the species most frequently observed in the Azores and constitutes an important component of the marine mammal tourism industry in this region. This study investigated the potential effects of tour boats on the behaviour of common dolphins off São Miguel, Azores, with particular focus on the changes in activity budget and the time required to resume activities after a tour boat interaction. Behavioural data were collected from land using a group focal-follow methodology. Markov chains were applied to analyse control and interaction sequences and to assess behavioural transition probabilities in both scenarios. In the presence of tour boats, dolphins significantly reduced the time spent foraging and increased the time engaged in other high energy activities. Dolphins also took significantly longer to resume feeding after an interaction occurred. The average bout length varied significantly between control and interaction scenarios, with foraging bouts being shorter during tour boats interactions. The results presented have management implications since feeding is a biologically critical activity. Disruption of foraging behaviour could lead to a decrease in energy intake for this population. With cetacean tourism likely to increase in the future, a precautionary approach to issuing new licences is advisable and any expansion would warrant an appropriate monitoring programme.

The biology of Canadian weeds. 128. Leucanthemum vulgare Lam.

2004 ◽  
Vol 84 (1) ◽  
pp. 343-363 ◽  
Author(s):  
David R. Clements ◽  
Dan E. Cole ◽  
Jane King ◽  
Alec McClay
Keyword(s):  
British Columbia ◽  
North America ◽  
Yukon Territory ◽  
Perennial Herb ◽  
Old Fields ◽  
Western Canada ◽  
Far North ◽  
Pasture Quality ◽  
Ray Florets ◽  
Noxious Weed

Leucanthemum vulgare Lam. (Asteraceae), known as ox-eye daisy, is a familiar perennial herb with white ray florets and yellow disc florets. It commonly inhabits roadside ver ges, pastures and old fields from Newfoundland to British Columbia, and also as far north as the Yukon Territory. Introduced from Europe, L. vulgare was well established in North America by 1800. The Canadian distribution of L. vulgare has expanded in many areas recently, particularly in western Canada. It can form dense populations that may reduce diversity of natural vegetation or pasture quality, and also serves as a host and reservoir for several species of polyphagous gall-forming Meloidogyne nematodes that feed on crops. It is considered a noxious weed under provincial legislation in Quebec, Manitoba, Alberta and British Columbia, as well as under the Canada Seeds Act. Control efforts are sometimes complicated by difficulties in distinguishing ox-eye daisy from some forms of the commercially available Shasta daisy ( L. × superbum).

Acoustic Assessment of Populations of Common Dolphin Delphinus Delphis In Conjunction With Seismic Surveying

1996 ◽  
Vol 76 (3) ◽  
pp. 811-820 ◽  
Author(s):  
John C. Goold
Keyword(s):  
Seismic Survey ◽  
Avoidance Reaction ◽  
Common Dolphin ◽  
Survey Area ◽  
Delphinus Delphis ◽  
Air Gun ◽  
Before And After ◽  
Seismic Surveying ◽  
Acoustic Contact ◽  
Common Dolphins

Common dolphin, Delphinus delphis (bairdi), were monitored acoustically across a survey area of 2747 km2 during a three month period before, during and after an oil industry two dimensional (2D) seismic reflection survey. Over 900 h of audio survey data were collected and analysed, along with GPS positional data, to reveal trends in presence and distribution of animals. The presence of dolphins was determined from vocalization events on the survey recordings. Dolphin presence was assessed by a system of percentage acoustic contact. This was highest before and after the seismic survey, with common dolphins showing a clear south-westerly skew within the survey area and a probable south-westerly migration of animals between September and December. Acoustic contact with dolphins during the seismic survey also showed a south-westerly skew within the survey area, although percentages were lower. Monitoring during the period of seismic activity was restricted to the immediate vicinity (1–2 km) of the seismic vessel, so percentage contact most likely reflects the response of dolphins to such immediate activity. The overall result suggests an avoidance reaction by common dolphins to air gun emissions, although certain observations suggest tolerance to these sounds outside a 1 km radius of the guns.

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