scholarly journals Temporal Variability of Cetaceans near Halifax, Nova Scotia

2006 ◽  
Vol 120 (1) ◽  
pp. 93 ◽  
Author(s):  
Peter Simard ◽  
Jennifer L. Lawlor ◽  
Shannon Gowans
Keyword(s):  
Nova Scotia ◽  
North Atlantic ◽  
Humpback Whales ◽  
Eubalaena Glacialis ◽  
Balaenoptera Acutorostrata ◽  
Minke Whales ◽  
North Atlantic Right Whales ◽  
Early Fall ◽  
Large Groups ◽  
Blue Whales

Annual and seasonal trends in sightings of coastal cetaceans near Halifax, Nova Scotia, were studied using observations from whale watching and dedicated research vessels from late spring to early fall of 1996 to 2005. Four species of cetaceans routinely used the area during the summer: White-beaked and Atlantic White-sided dolphins (Lagenorhynchus albirostris and L. acutus), Harbour Porpoises (Phocoena phocoena), and Minke Whales (Balaenoptera acutorostrata). The dolphin species were temporally separated, with White-beaked Dolphins being common earlier in the summer than White-sided Dolphins. White-sided Dolphins were unusually abundant in 1997, and were found in larger groups (mean = 46.5 ± 46.19 sd) than Whitebeaked Dolphins (mean = 9.1 ± 5.19 SD). The area also appears to be an important habitat for dolphin calves and juveniles of both species. Fin Whales (B. physalus) were commonly observed in relatively large groups in 1997, but were uncommon or absent in other years. Humpback Whales (Megaptera novaeangliae), Blue Whales (B. musculus) and North Atlantic Right Whales (Eubalaena glacialis) were uncommon in the area, although Humpback Whales were sighted frequently in 1997. Increased numbers of White-sided Dolphins, Fin and Humpback whales in 1997 may be explained by increased prey abundance and decreased sea-surface temperatures.

Pilot cetacean survey of the sub-Arctic North Atlantic utilizing a cruise-ship platform

2007 ◽  
Vol 87 (1) ◽  
pp. 321-325 ◽  
Author(s):  
Ross Compton ◽  
Aaron Banks ◽  
Lissa Goodwin ◽  
Sascha K. Hooker
Keyword(s):  
North Atlantic ◽  
Large Scale ◽  
North Atlantic Ocean ◽  
Distance Sampling ◽  
Weather Conditions ◽  
Humpback Whales ◽  
Cruise Ship ◽  
Balaenoptera Acutorostrata ◽  
Cetacean Species ◽  
Minke Whales

Using a large passenger cruise-ship (MV ‘Discovery’) as a platform, a cetacean survey was conducted between 1 August and 3 September 2005 across the northern North Atlantic Ocean and back, covering waters between the UK, Iceland, Greenland and Canada. The objective was to collect sightings data for all cetacean species encountered to begin to collate information for a large-scale sightings database. Two observers employed standard-distance sampling techniques and visual observations (naked eye) to scan for cetaceans during daylight hours and favourable weather conditions. Approximately 112 h were spent surveying over 23 d. A total of 13 cetacean species were encountered, with 173 separate sightings recorded, totalling over 2000 animals. The most commonly sighted species were minke whales (Balaenoptera acutorostrata: N=44), Atlantic white-sided dolphins (Lagenorhynchus acutus: N=34, with group sizes of up to 600), and humpback whales (Megaptera novaeangliae: N=31). The distribution of minke whales, Atlantic white-sided dolphins and fin whales was linked to underlying oceanographic variables. Overall patterns of distribution were consistent with our understanding of the summer distributions for the species encountered. The survey highlighted the cetacean diversity of the northern North Atlantic region. Repeat work using this methodology will allow an examination of species' distributions and estimation of their relative abundance.

Aerial surveys of cetaceans in the Gulf of St. Lawrence in 1995 and 1996

1998 ◽  
Vol 76 (8) ◽  
pp. 1529-1550 ◽  
Author(s):  
MCS Kingsley ◽  
R R Reeves
Keyword(s):  
Humpback Whales ◽  
Delphinapterus Leucas ◽  
Line Transect ◽  
Balaenoptera Acutorostrata ◽  
North Shore ◽  
The North ◽  
Minke Whales ◽  
Fin Whales ◽  
Pilot Whales ◽  
Blue Whales

Aerial line-transect surveys of cetaceans were flown in the Gulf of St. Lawrence in late August and early September of 1995 and in late July and early August of 1996. Systematic north-south transects were spaced 15prime of longitude apart. In 1995, the study area comprised the entire Gulf, divided into three strata for analysis; 69% was flown. In 1996, a single stratum covered only the north shore shelf; 75% of the design was flown. The survey platform was a light high-winged aircraft with bubble windows flown at 213 m (700 ft). Ten species were seen. Minke whales (Balaenoptera acutorostrata), Atlantic white-sided dolphins (Lagenorhynchus acutus), and harbour porpoises (Phocoena phocoena) yielded enough sightings to support good estimates, while fin whales (Balaenoptera physalus), humpback whales (Megaptera novaeangliae), white-beaked dolphins (Lagenorhynchus albirostris), and long-finned pilot whales (Globicephala melas) yielded few sightings and unreliable estimates. Blue whales (Balaenoptera musculus) and belugas (Delphinapterus leucas) were seen too rarely to support any analysis. The tenth species was a small delphinid, not positively identified. Minke whales were ubiquitous, but more common in the northern strata. We estimated about 1000 in the whole Gulf in 1995 and about 600 in the northernmost stratum in 1996 (these numbers, and those following, are uncorrected for visibility bias). We estimated about 12 000 Atlantic white-sided dolphins in the Gulf in 1995, but in 1996 saw hardly any, perhaps because we flew the survey earlier. Harbour porpoises (12 000 in 1995 and 21 000 in 1996) were most numerous in the northern stratum, but were also widely distributed at lower densities in the central and southern Gulf. White-beaked dolphins (2500 in 1995 and 2500 in 1996) occurred only in the Strait of Belle Isle and the extreme northeastern Gulf. We estimated a few hundred fin whales in the northern and central strata and about 100 humpbacks, mostly in the northeast. Long-finned pilot whales were only seen in the southeastern Gulf, surveyed only in 1995 (about 1500).

scholarly journals A Multi-elemental Approach to Identification of Subpopulations of North Atlantic Minke Whales Balaenoptera Acutorostrata

2007 ◽  
Vol 13 (1) ◽  
pp. 84-97 ◽  
Author(s):  
Erik W. Born ◽  
Michael C. S. Kingsley ◽  
Frank F. Rigét ◽  
Rune Dietz ◽  
Per Møller ◽  
...  
Keyword(s):  
North Atlantic ◽  
Balaenoptera Acutorostrata ◽  
Minke Whales
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