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 More of the same: allopatric humpback whale populations share acoustic repertoire

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5365 ◽  
Author(s):  
Michelle E.H. Fournet ◽  
Lauren Jacobsen ◽  
Christine M. Gabriele ◽  
David K. Mellinger ◽  
Holger Klinck
Keyword(s):  
North Atlantic ◽  
North Atlantic Ocean ◽  
North Pacific Ocean ◽  
Humpback Whale ◽  
Humpback Whales ◽  
Massachusetts Bay ◽  
Baleen Whale ◽  
Southeast Alaska ◽  
Allopatric Populations ◽  
Strong Contrast

Background Humpback whales (Megaptera novaeangliae) are a widespread, vocal baleen whale best known for producing song, a complex, repetitive, geographically distinct acoustic signal sung by males, predominantly in a breeding context. Humpback whales worldwide also produce non-song vocalizations (“calls”) throughout their migratory range, some of which are stable across generations. Methods We looked for evidence that temporally stable call types are shared by two allopatric humpback whale populations while on their northern hemisphere foraging grounds in order to test the hypothesis that some calls, in strong contrast to song, are innate within the humpback whale acoustic repertoire. Results Despite being geographically and genetically distinct populations, humpback whales in Southeast Alaska (North Pacific Ocean) share at least five call types with conspecifics in Massachusetts Bay (North Atlantic Ocean). Discussion This study is the first to identify call types shared by allopatric populations, and provides evidence that some call types may be innate.

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.

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.

scholarly journals Smart Fert: Aplikasi Praktis, Valid, dan Mudah Untuk Mengukur Indikator Fertilitas di Era Otonomi Daerah

Populasi ◽  
2018 ◽  
Vol 25 (1) ◽  
pp. 33
Author(s):  
Lutfi Agus Salim ◽  
Lutfan Lazuardi ◽  
Kuntoro Kuntoro
Keyword(s):  
Total Fertility Rate ◽  
Birth Rate ◽  
Crude Birth Rate ◽  
Visual Basic ◽  
Reproductive Rate ◽  
Fertility Rate ◽  
General Fertility Rate

Indikator fertilitas, seperti Crude Birth Rate (CBR), Total Fertility Rate (TFR), General Fertility Rate (GFR), dan Gross Reproductive Rate (GRR), untuk mengukur kinerja pengendalian penduduk setiap tahun di level kabupaten/kota sejak otonomi daerah sering tidak tersedia. Aplikasi sistem informasi fertilitas Smart Fert sebagai alat untuk mengukur indikator fertilitas yang praktis, valid, dan mudah diaplikasikan sangat layak untuk dikembangkan. Tujuan penelitian ini adalah mengembangkan aplikasi Smart Fert serta menguji hasil perhitungan indikator fertilitas dari aplikasi Smart Fert dibandingkan dengan perhitungan dari hasil Sensus Penduduk 2010. Penelitian ini merancang aplikasi Smart Fert berbasis bahasa visual basic. Untuk mengukur ketepatan dan kevalidan hasil perhitungan fertilitas dari aplikasi Smart Fert, maka hasilnya dibandingkan dengan standar yang baik, yaitu hasil Sensus Penduduk 2010. Hasil penelitian menunjukkan bahwa hasil perhitungan fertilitas dengan aplikasi Smart Fert tidak menunjukkan perbedaan signifikan dengan hasil metode langsung Sensus Penduduk 2010. Dengan demikian, aplikasi Smart Fert dapat dipakai sebagai alat penghitung indikator fertilitas yang praktis, valid, dan mudah diimplementasikan untuk mengukur kinerja pengendalian penduduk di tingkat kabupaten/kota.

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.

The impact of entanglements on two substocks of the western North Atlantic humpback whale, Megaptera novaeangliae

1995 ◽  
Vol 73 (9) ◽  
pp. 1689-1698 ◽  
Author(s):  
Lisa Volgenau ◽  
Scott D. Kraus ◽  
Jon Lien
Keyword(s):  
North Atlantic ◽  
Newfoundland And Labrador ◽  
Birth Rate ◽  
Gulf Of Maine ◽  
Humpback Whale ◽  
Megaptera Novaeangliae ◽  
Fishing Gear ◽  
The Impact ◽  
Annual Mortality ◽  
Mortality Estimates

Increased use of fishing gear in the marine environment can be detrimental to animals such as cetaceans, particularly through entanglement. Examination of the impact of such mortality on two substocks of the western North Atlantic humpback whale, Megaptera novaeangliae, indicates that when entanglement losses are added to natural mortality estimates and subtracted from birth rate estimates, annual mortality may be as high as 5.4% in the Newfoundland and Labrador population and 4.8% in the Gulf of Maine population. More effective entanglement reporting and assisting systems are needed in the Gulf of Maine and increased efforts are needed to decrease entanglements, entanglement mortalities, and damages to fishing gear. We conclude that monitoring of the size of humpback populations needs to continue, given their particular vulnerability to coastal fishing and the potential impacts of entanglement mortality.

Influence of krill ( Euphausia superba ) availability on humpback whale ( Megaptera novaeangliae ) reproductive rate

2021 ◽  
Author(s):  
Elisa Seyboth ◽  
Fernando Félix ◽  
Mary‐Anne Lea ◽  
Luciano Dalla Rosa ◽  
George M. Watters ◽  
...  
Keyword(s):  
Euphausia Superba ◽  
Humpback Whale ◽  
Reproductive Rate ◽  
Megaptera Novaeangliae

scholarly journals Very low numbers of endangered Oceania humpback whales seen in Fijian waters

2015 ◽  
Vol 33 (2) ◽  
pp. 39 ◽  
Author(s):  
C. Miller ◽  
A. Batibasiga ◽  
S. Sharma-Gounder ◽  
P. Solomona
Keyword(s):  
Southern Hemisphere ◽  
Humpback Whale ◽  
Megaptera Novaeangliae ◽  
Humpback Whales ◽  
Large Decrease ◽  
The South ◽  
Migration Routes ◽  
Antarctic Waters ◽  
Commercial Whaling

Intensive commercial whaling caused significant declines in Southern Hemisphere humpback whale (Megaptera novaeangliae) populations. In Fiji, land-based humpback whale surveys undertaken from 1956 to 1958 documented maximum weekly counts of more than 150 humpback whales in parts of the Bligh waters. These records provide an invaluable point of comparison to present-day observations as they occurred immediately prior to very large humpback whale catches in Antarctic waters to the south – and on potential migration routes – of humpback whales breeding in Fijian waters. We report here on a three-year (2010–2012) land-based survey also conducted in the Bligh waters during which a total of 33 individuals over 480 h were counted from Ovalau Island and 68 individuals over approximately 300 h were observed from Makogai Island. These findings suggest a large decrease in numbers of humpback whales seen in Fiji waters since commercial whaling operations.

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