Subject: Humpback whales; whaling, predation, populations
Lindsay J Porter (h9390327@hkucc.hku.hk)
Sun, 12 Apr 1998 14:27:22 +0800 (HKT)
>My questions will help me with my reaserch paper for college.
>I would like to know some history about whaling concerning Humpback
>whales. When was whaling first started? How much damage whalers did to
>Humpback population? What countries are still whaling? Who was a major
>influnce in banning whaling?
>
>Is there another preditor towards the Humpback population? What
>Polutants in the oceans waters have effected the Humpback's?
>
> If you could provide me with these answers or where I can find these
>answers on the net I would appreciate it. A little note the computer does not
>like me I can never find anything I need on the net. I have even looked at
>WhaleNet. No help to me. Thank you!
Please find following soem information on baleen/humpback/whaling information
At the two websites below you will find the IWC regulations, with
participating countries
http://www.physics.helsinki.fi/whale/iwc/iwc1946.html
http://www.physics.helsinki.fi/whale/iwc/reg1946/reg1946.html
The following two sites give information on eth current whaling (legal and
illegal) within Asia
http://www.traffic.org/pr_whale_meat.html
http://www.traffic.org/summary_whale_meat.html
This site gives information on rorquals in general
http://www.oit.itd.umich.edu/bio/Chordata/Mammalia/Cetacea/Balaenopteridae.shtml
Articles on humpbacks that may help you are
TitleSeasonal distribution, exploitation and present abundance of stocks of
large baleen whales (Mysticeti) and sperm
whales (Physeter macrocephalus) in Norwegian and adjacent waters.
Author(s)
CHRISTENSEN-I; HAUG-T; OIEN-N
Source Journal
ICES (INTERNATIONAL COUNCIL FOR THE EXPLORATION OF THE SEA) JOURNAL OF
MARINE
SCIENCE 49(3): 341-355
Publication Year
1992
Language of Article
English
Abstract
An account of the annual distribution and previous exploitation of
Greenland right (Balaena mysticetus), blue
(Balaenoptera musculus), fin (Balaenoptera physalus), sei (Balaenoptera
borealis), humpback (Megaptera
novaeangliae) and sperm whales (Physeter macrocephalus) in Norwegian
and adjacent water is presented. Where
possible, the present abundances of these species are updated with data
from sightings surveys conducted in these
waters in 1987-1989. The Greenland right whale is rarely seen and is
probably nearly extinct. The blue whale seems
to be regularly migrating into the Norwegian Sea up to the west of
Spitsbergen in summer, but its abundance is not
known. Recent survey estimates indicate a fin whale populations of some
thousands in the Norwegian Sea in summer.
The recent sightings surveys have revealed no new information on sei
whale abundance in these areas. Humpbacks
amount to approximately 1000 whales in the Norwegian and Barents Seas,
while sperm whales number several
thousand in the Norwegian Sea. In total, up to 10 000 individuals of
the large whale species inhabit these northern
waters during the summer. .
TitleLarge-scale planning for assessment and recovery of humpback whale
populations.
Author(s)
KATONA-S-K
Source Journal
MEMOIRS OF THE QUEENSLAND MUSEUM 30(2): 297-306
Publication Year
1991
Language of Article
English
Abstract
Planning to help humpback whale populations recover from past
commercial hunting must acknowledge their second
diversity of habitats, frequently governed by different nations, where
there are affected by human activities such as
shipping, fishing, dregding, waste disposal, and others. Human-induced
changes in ocean ecology or resource
abundance make it unlikely that populations could regain aboriginal
sizes. Comprehensive research programs to assess
present distribution and population sizes will usually require
coordinated efforts by scientists from many nations.
Estimation of present population size is facilitated by seasonal
aggregation of whales at feeding or breeding locations,
but poor estimation of prehunting abundance make it hard to choose a
desired population size or to evaluate present vs
past populations. Some populations may require many decades to reach
desired populations size, owing to the whales'
tendency to return to traditional locations and their slow rate of
reproduction. Monitoring programs must be long term.
The U.S. Humpback Whale Recovery Plan is discussed as an example of a
large scale plan covering 3 stocks of
humpback whales in two oceans. A research proposal, entitled Years of
the North Atlantic Humpback (YONAH),
to assess population sizes and movements by an intensive international
synoptic study throughout the summer and
winter range of the species is summarized. .
TitleCatches of humpback and other whales from shore stations at Moss
Landing and Trinidad, California, 1919-1926.
Author(s)
Clapham-P-J; Leatherwood-S; Szczepaniak-I; Brownell-R-L-Jr
Source Journal
Marine Mammal Science 13(3): 368-394
Publication Year
1997
Language of Article
English
Abstract
Logbook data from California shore whaling stations at Moss Landing
(1919-1922 and 1924) and Trinidad (1920 and
1922-1926) are analyzed. The logs for the two stations record the
taking of 2,111 whales, including 1,871
humpbacks, 177 fin whales, 26 sei whales, 3 blue whales, 12 sperm
whales, 7 gray whales, 1 right whale, 1
Baird's beaked whale, and 13 whales of unspecified type (probably
humpbacks). Most whales were taken from
spring to autumn, but catches were made in all months of some years.
The sex ratios of humpback, fin, and sei whales
(the three species with sufficient sample sizes to test) did not differ
from parity. Primary prey, determined from stomach
contents, included sardines and euphausiids for both humpback and fin
whales, and "plankton" (probably
euphausiids) for sei whales. The prevalence of pregnancy was 0.46 among
mature female humpbacks and 0.43
among mature female fin whales, although these values are reported with
caution. Information on length distribution for
all species is summarized. Analysis of the catch data for this and
other areas supports the current view that humpback
whales along the west coast of the continental United States comprise a
single feeding stock and also suggests that the
present population is well below pre-exploitation levels. .
TitleChlorinated organic contaminants in blubber biopsies Northwestern
Atlantic balaenopterid whales summering in the
Gulf of St. Lawrence.
Author(s)
Gauthier-J-M; Metcalfe-C-D; Sears-R
Source Journal
Marine Environmental Research 44(2): 201-223
Publication Year
1997
Language of Article
English
Abstract
Concentrations and patterns of chlorinated biphenyls (CBs) and other
persistent organochlorine compounds (OCs)
were determined from small blubber biopsy samples collected from
northwestern Atlantic minke (Balaenoptera
acurostrata), fin (Balaenoptera physalus), blue (Balaenoptera
musculus), and humpback (Megaptera novaeangliae)
whales summering in the Gulf of St. Lawrence, Quebec. Concentrations of
SIGMA-PCB (sum of 19 congeners) in
biopsy samples ranged from 0.2-10 mu-g g-1 lipid, and congeners 52,
101, 118, 153, 138 and 180 accounted for
79% of SIGMA-PCB. Mean concentration of the sum of non-ortho CB
congeners in selected biopsy samples was 2
ng g-1 lipid, and relative concentrations of these analytes were: 77 gt
126 gt 81 gt 169. Concentrations of
SIGMA-DDT ranged from 0.6-13 mu-g g-1 lipid, and the average proportion
of DDE to SIGMA-DDT was 72%.
All other organochlorine analytes were present at concentrations below
2 mu-g g-1 lipid. On average, cis-nonachlor,
trans-nonachlor and oxychlordane accounted for 27, 26 and 23%,
respectively, of the chlordane-related analytes, and
alpha-hexachlorocyclohexane (HCH) comprised 67% of SIGMA-HCH.
Concentrations of SIGMA-DDT were
significantly lower and mirex concentrations were significantly higher
in minke whales than in the other balaenopterid
species. Concentrations of all other analytes were similar in the four
whale species. Ratios of proportions of
oxychlordane to trans-nonachlor were highest in fin whales. Blue whales
had the lowest proportions of alpha-HCH
but the highest proportions of DDT. Interspecies differences in the
concentrations and patterns of certain CB
congeners and OC compounds may reflect differences in diet or in
metabolic capabilities. Males usually had higher
mean concentrations of CBS and OCs than females, but these differences
were significant only for SIGMA-DDT,
dieldrin, SIGMA-HCH and HCB. Higher proportions of lower chlorinated CB
congeners were found in calves
compared to adult females, indicating selective reproductive transfer. .
TitleA Review of the Catch Statistics for Modern Whaling in Southern Africa,
1908-1930.
Author(s)
Best-P-B
Source Journal
Report of the International Whaling Commission 0(44): 467-485
Publication Year
1994
Language of Article
English
Abstract
Between 1908 and 1930, the coast of southern Africa was the most
important whaling ground outside the Antarctic,
but 28% of the recorded catch was unspecified or approximate in number.
Using sources as contemporary to the
operations as possible, this paper attempts to fill in missing data,
correct errors and resolve uncertainties in the catch
series. In total, 73,526 whales are estimated to have been taken on the
southern African coast between 1908 and
1930, consisting of 14,226 blue, 14,150 fin, 4,369 sei, 815 Bryde's,
31,042 humpback, 67 right and 8,857 sperm
whales. The catch on the west coast was approximately twice that on the
east coast. Uncertainty still surrounds early
catches in Angola, the Congo and Mozambique. .
OTHER PREDATORS!!!!!!
TitleAttack of killer whales (Orcinus orca) on humpback whales (Megaptera
novaeangliae) on a South American Pacific
breeding ground.
Author(s)
Florez-Gonzalez-L; Capella-J-J; Rosenbaum-H-C
Source Journal
Marine Mammal Science 10(2): 218-222
Publication Year
1994
Language of Article
English .
TitleThe social and reproductive biology of Humpback whales: An ecological
perspective.
Author(s)
Clapham-P-J
Source Journal
Mammal Review 26(1): 27-49
Publication Year
1996
Language of Article
English
Abstract
Existing knowledge of the social organization, mating system and
reproduction of Humpback Whales (Megaptera
novaeangliae) is reviewed to assess how our current understanding of
this wide-ranging marine mammal fits into the
predictive framework developed from ecological studies of more
accessible terrestrial taxa. The small unstable groups
characteristic of this species on its summer feeding grounds appear to
be a function of absence of predation and of the
patchy, mobile nature of most prey; the absence of territoriality and
the minimal importance of kinship in associations
are also predictable consequences of the latter. The mating system is
similar to both leks and to male dominance
polygyny, in which males display (sing) or directly compete (perhaps
sometimes in coalitions) for access to females.
However, the rigid spatial structure characteristic of classic leks is
absent. The mating system of this species is
sufficiently different to merit a novel category, and 'floating lek' is
proposed. The widespread distribution of females
resulting from absence of both predation and resources during the
breeding season preclude simultaneous
monopolization by males of more than one potential mate. Furthermore,
these factors, together with a male-biased
operational sex ratio, minimize the possibility of competition among
females. The intensity of intrasexual competition
among males conforms to predictions derived from information on testis
size and from expectation of future
reproductive success. Female choice and, to a lesser extent,
differential allocation of competitive effort by males,
appears likely. Lack of interpopulation variation in social and mating
behaviour, and in general reproductive biology, is
likely a response to similarity of marine environmental conditions.
Year-to-year variation in reproductive rates may be
linked to variations in the abundance of prey. The invariably uniparous
nature of female Humpback Whales is
assumed to be related to the energetic demands of lactation, and the
lower ratio of available energy partitioned to
reproduction that is characteristic of larger mammals. The reversed
sexual size dimorphism of this species may reflect
different selective pressures on males and females. Finally, there is
now evidence that, as in some other taxa, offspring
sex ratio is related to maternal condition. .
TitleHumpback whales (Megaptera novaeangliae) in Hervey Bay, Queensland:
Behaviour and responses to
whale-watching vessels.
Author(s)
Corkeron-P-J
Source Journal
Canadian Journal of Zoology 73(7): 1290-1299
Publication Year
1995
Language of Article
English
Abstract
The effects of the presence of vessels on the behaviour of humpback
whales (Megaptera novaeangliae) was studied
in Hervey Bay, Queensland, where southward-migrating whales are the
focus of a commercial whale-watching
industry. The behaviour of whales was observed from a small yacht under
sail. Rates of occurrence of units of
behaviour for entire pods were obtained from continuous sampling of
pods. Pods without calves showed lower rates of
behaviour generally when vessels were within 300 m of them. Pods both
with and without calves were more likely to
dive rather than slip under when vessels were within 300 m. Hybrid
multidimensional scaling of rates of behaviours of
pods indicated differences between suites of behaviours exhibited by
pods when vessels were within 300 m of them
and when they were not. Classification of the patterns of occurrence of
behaviours demonstrated that for pods both
with and without calves, different units of behaviour tended to occur
together when vessels were within 300 m and
when they were not. Whale watching offers a nonlethal commercial use of
whales, but in Hervey Bay, whale
watching affects the behaviour of whales, which, although migrating,
can be involved in breeding ground activities.
Whether the short-term behavioural changes described here are
accompanied by longer term avoidance of Hervey
Bay by humpback whales as they migrate south remains to be determined. .
I hope these help
best wishes
Lindsay J Porter
email h9390327@hkucc.hku.hk
Dolphin Research Group
The Swire Institute of Marine Science
The University of Hong Kong
Cape d'Aguilar
Hong Kong
website: http://www.webdivers.co.uk/dolphin/index.html