scholarly journals Humpback Whale (Megaptera novaeangliae) observations in Laskeek Bay, western Hecate Strait, in spring and early summer, 1990–2018

2020 ◽  
Vol 133 (3) ◽  
pp. 263-269
Author(s):  
Anthony J. Gaston ◽  
Neil G. Pilgrim ◽  
Vivian Pattison
Keyword(s):  
British Columbia ◽  
Humpback Whale ◽  
Early Summer ◽  
Megaptera Novaeangliae ◽  
Humpback Whales ◽  
The West ◽  
Peak Period ◽  
West Side

We describe observations of Humpback Whales (Megaptera novaeangliae) made along the west side of central Hecate Strait, British Columbia, during the spring and summer of 1990–2018. From none in March, the frequency of sightings increased from early April to a peak in May, then fell in June with few in July. The frequency of sightings during the peak period (1 May–20 June) increased over the course of the study at a mean rate of 6% a year, similar to increases recorded elsewhere in British Columbian waters. The frequency of sightings was highest in years when the Oceanic Niño Index for January–March was low and peaked earlier in years when the Oceanic Niño Index was high. Both of these relationships suggest a connection between Humpback Whale sightings in western Hecate Strait and the larger oceanographic context, with sightings more frequent in years of lower water temperatures.

Population Estimate of the Humpback Whale (Megaptera novaeangliae) in the West Indies by Visual and Acoustic Techniques

1975 ◽  
Vol 32 (4) ◽  
pp. 499-506 ◽  
Author(s):  
H. E. Winn ◽  
R. K. Edel ◽  
A. G. Taruski
Keyword(s):  
North Atlantic ◽  
West Indies ◽  
Total Population ◽  
Humpback Whale ◽  
Megaptera Novaeangliae ◽  
New Method ◽  
Population Estimate ◽  
The West ◽  
Acoustic Techniques

Visual track census and a new method, acoustic counting, were used to estimate the humpback whale (Megaptera novaeangliae) population in the West Indies. Results produced by the two methods differed to some extent. The average or best estimate was 1018 whales with a range of 785–1157. Silver and Navidad banks, containing approximately 85% of the total population, are presently the major nursery grounds in the West Indies. The humpback whale population in the western North Atlantic has increased since the early part of the century.

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.

Multiple visits of individual humpback whales (Megaptera novaeangliae) between the Hawaiian and Japanese winter grounds

1999 ◽  
Vol 77 (3) ◽  
pp. 504-508 ◽  
Author(s):  
Dan R Salden ◽  
Louis M Herman ◽  
Manami Yamaguchi ◽  
Fumihiko Sato
Keyword(s):  
Genetic Variability ◽  
North Pacific ◽  
Humpback Whale ◽  
Megaptera Novaeangliae ◽  
Humpback Whales ◽  
Winter Ground ◽  
The Third ◽  
Breeding Populations ◽  
Published Report

We document through photographic identifications three humpback whale (Megaptera novaeangliae) winter ground interchanges between Hawai'i and Japan. Two of these whales, identified as male by their behavioral roles, made multiple interchanges across years; i.e., they were initially seen in Hawai'i, were later observed in Japan, and subsequently, returned to Hawai'i. The third whale was seen in only 2 different years, once in Japan and then in Hawai'i. Prior to this report, there has been only one published report of a Hawai'i-Japan interchange and only eight between Hawai'i and Mexico. None of these involved multiple interchanges. The current findings demonstrate that individual whales may be highly flexible in their annual choice of widely separated winter destinations and suggest that these wanderers may be mainly males. The occurrence of wanderers provides a mechanism for increasing genetic variability in the breeding populations and also suggests a mechanism for noted song similarities across different North Pacific winter grounds.

Male mate choice and male-male competition coexist in the humpback whale (Megaptera novaeangliae)

2002 ◽  
Vol 80 (4) ◽  
pp. 745-755 ◽  
Author(s):  
Alison S Craig ◽  
Louis M Herman ◽  
Adam A Pack
Keyword(s):  
Mate Choice ◽  
Reproductive Potential ◽  
Humpback Whale ◽  
Male Competition ◽  
Megaptera Novaeangliae ◽  
Reproductive Season ◽  
Humpback Whales ◽  
Male Mate Choice ◽  
Calving Rate ◽  
Male Mate

Male humpback whales (Megaptera novaeangliae) outnumber females on the winter grounds and compete physically for proximity to females. Analyses of identification photographs collected in Hawai'i from 1976 through 1995 and scan samples collected in 1998 showed that (i) reproductive potential (calving rate) for the following winter was greater for females without a calf than females with a calf, (ii) females without a calf were less likely to be found alone and more likely to be found in large pods than females with a calf, (iii) individual females were found in larger pods when without a calf than when with a calf, (iv) the probability of females with a calf being escorted by one or more males increased as the reproductive season progressed, and (v) head lunges occurred more commonly in all-adult pods than in pods containing a calf. We concluded that male humpback whales associate preferentially with females with high reproductive potential, that the attractiveness of individual females varies with their status (with a calf versus without a calf), that males become progressively less choosy over the course of the reproductive season as females without a calf become increasingly rare on the winter grounds, and that males expend more energy in competition over females without a calf than females with a calf.

Reproduction and recruitment of individually identified humpback whales, Megaptera novaeangliae, observed in Massachusetts Bay, 1979–1985

1987 ◽  
Vol 65 (12) ◽  
pp. 2853-2863 ◽  
Author(s):  
Phillip J. Clapham ◽  
Charles A. Mayo
Keyword(s):  
Birth Rate ◽  
Crude Birth Rate ◽  
Humpback Whale ◽  
Mature Female ◽  
Reproductive Rate ◽  
Megaptera Novaeangliae ◽  
Humpback Whales ◽  
Massachusetts Bay ◽  
High Return ◽  
Calving Intervals

Humpback whale mother–calf pairs from a currently unexploited population were observed in Massachusetts Bay between 1979 and 1985. During this period, 44 individually identified mature females were observed, with a total of 72 calves. Of the 20 mothers observed with more than one calf during the study period, 12 had two calves and 8 had three calves. The observed calving intervals were 1 year (n = 1), 2 years (n = 16), 3 years (n = 10), and 4 years (n = 1). The crude birth rate varied from a low of 0.045 in 1981 to a high of 0.103 in 1983 (mean = 0.075). An alternative calculation of reproductive rate yielded a range of 0.30–0.43 calves per mature female per year. Mature females were observed significantly more frequently in years when they had a calf than in years when they did not. Females with calves associate with other whales less frequently than females without calves. Observations of calves feeding suggest that weaning may begin when calves are 5–6 months of age. Forty-five of the 49 calves born before 1985 separated from their mothers during the calf's second winter, while 37 of the 49 were observed to return to the study area in 1 or more years after separation from their mothers. One calf is known to have died. Two females born during the study period returned with calves of their own in later years. The high return rate of calves in years after separation strongly suggests that the composition of a humpback whale feeding stock is determined matrilineally.

scholarly journals Seasonal Variation of Temperature and Salinity of Surface Waters of the British Columbia Coast

1953 ◽  
Vol 10 (3) ◽  
pp. 125-145 ◽  
Author(s):  
G. L. Pickard ◽  
D. C. McLeod
Keyword(s):  
British Columbia ◽  
West Coast ◽  
Sea Water ◽  
Deep Ocean ◽  
Vancouver Island ◽  
Early Summer ◽  
The West ◽  
Queen Charlotte Islands ◽  
Land Drainage ◽  
Run Off

Grand monthly means of daily observations of surface sea-water temperature and salinity from twelve light stations along the British Columbia coast during the 13 years 1935 to 1948 have been analysed. In general the temperatures reach a minimum of 45°F. ± 1° (7.2 °C. ± 0.5°) in January and February. The maximum varies from 50° to 64°F. (10° to 18 °C.) in August. The warmest waters occur in bays protected from wind action, and the coldest waters occur in regions of turbulent mixing due to wind or strong currents. The salinity along the mainland coast is a minimum in early summer, associated with the maximum run-off from melting snow. Along the west coast of Vancouver Island the minimum occurs in mid-winter, associated with maximum precipitation which is not stored as snow in this region. At the southern and northern tip of the Queen Charlotte Islands there is little or no variation of salinity because there is no land drainage of consequence in the vicinity.In passes between Georgia Strait and the sea where the waters are mixed to homogeneity by strong tidal currents the annual variation of temperature and salinity is reduced, and in some cases entirely suppressed.On the west coast of Vancouver Island it is shown that the annual cycle is affected by the dominant winds and upwelling of deep ocean waters.

scholarly journals Surface activity of Humpback whales Megaptera novaeangliae (Cetacea, Mysticeti) on the northern coast of Bahia, Brazil

2020 ◽  
Vol 21 (1) ◽  
pp. 1-12
Author(s):  
Leonardo Leão Versiani ◽  
Cristiano Schetini Azevedo
Keyword(s):  
Surface Activity ◽  
Humpback Whale ◽  
Megaptera Novaeangliae ◽  
Humpback Whales ◽  
Northern Coast ◽  
Sea State ◽  
Surface Activities ◽  
Cloud Coverage

Surface activities of humpback whale groups were studied during the reproductive seasons of 2008, 2009 and 2010 on the northern coast of Bahia State, Brazil, near the district of Praia do Forte. The level of surface activity exhibited by 342 groups of whales was evaluated according to the sea state (measured on the Beaufort scale) and cloud coverage. Five behaviours were recorded: breaching, head slapping, tail slapping, pectoral flipper slapping and tail breaching. Most of the sightings occurred with a sea state classified on the Beaufort scale as 2, and with a cloud coverage of 26 to 50%. The most recorded level of surface activity was pectoral flipper slapping. The results showed that humpback whale behaviours do not seem to be influenced by the sea state or by cloud coverage.

North Atlantic humpback whale (Megaptera novaeangliae) hotspots defined by bathymetric features off western Puerto Rico

2016 ◽  
Vol 94 (7) ◽  
pp. 517-527 ◽  
Author(s):  
M.M. MacKay ◽  
B. Würsig ◽  
C.E. Bacon ◽  
J.D. Selwyn
Keyword(s):  
Puerto Rico ◽  
North Atlantic ◽  
Humpback Whale ◽  
Current Data ◽  
Megaptera Novaeangliae ◽  
Humpback Whales ◽  
Shelf Edge ◽  
Species List ◽  
Occurrence Patterns ◽  
Potential Interactions

North Atlantic humpback whales (Megaptera novaeangliae (Borowski, 1781)) are increasing in number, necessitating current data from winter areas for assessing potential interactions with humans. Occurrence patterns of humpback whales wintering off Puerto Rico were investigated to predict where whales aggregate in nearshore areas. Here we describe the relationship between group associations of humpback whales and bathymetric features off western Puerto Rico. Data were collected from 2011 to 2014. Effort consisted of 240.9 vessel h, 13.0 aerial h, and 303.6 h of land observations conducted over 165 days. A total of 197 humpback whale groups were observed with n = 331 individuals: 91 (46.2%) singletons, 67 (34%) dyads, 17 (8.6%) mother–calf pairs, 8 (4.1%) competitive groups, 8 (4.1%) mother–calf–escort groups, and 6 (3.1%) mixed-species associations. A linear regression model supported that group composition correlated with hotspots associated with four bathymetric features. Dyads and competitive groups were dispersed among features in deeper water. Singletons were observed farther from a shelf edge, whereas singing males were closely associated with a shelf edge. Mother–calf pairs occurred nearshore in shallow water; however, when mother–calf pairs were sighted with an escort, they were offshore. This study is especially important ahead of possible removal from the Endangered Species list.

scholarly journals Earlier Sightings of Humpback Whales in Antarctica

Oryx ◽  
1982 ◽  
Vol 16 (5) ◽  
pp. 430-430
Author(s):  
Peter Kinnear
Keyword(s):  
Antarctic Peninsula ◽  
West Coast ◽  
Megaptera Novaeangliae ◽  
Humpback Whales ◽  
The West ◽  
British Antarctic Survey ◽  
The Antarctic

Nigel Bonner has documented sightings of humpbacks Megaptera novaeangliae off the west coast of the Antarctic Peninsula which seem to indicate some recovery of stocks (Oryx 16, 3: 231–232). It may therefore be worth placing on record the following sightings of this species made from Argentine Islands for 1970/72, when I was stationed at the British Antarctic Survey base.

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