Dear Marmam subscribers,
The following are abstracts from the most recent issue (Volume 13, issue 3,
2013) of the Journal of Cetacean Research and Management. The following is
posted on behalf of the IWC and the journal editor.
The International Whaling Commission (IWC) publishes the Journal of Cetacean
Research and Management thrice yearly (Spring, Autumn, and Winter), with at
least one supplement that will contain the full report of the IWC Scientific
Committee.
This is one of the final issues of JCRM to be published in hard copy format.
The IWC is delighted to inform you that the Journal of Cetacean Research and
Management will be available free of charge online from Volume 14
(https://iwc.int/jcrm). Back copies will also be available free of charge on
the IWC website. Some back copies of the Journal of Cetacean Research and
Management are available in hard copy format, and these are available for the
cost of postage only. For further details, please contact secretar...@iwc.int.
Contact information is provided for the corresponding author for each article.
Please do not contact the listserve editors or me for pdfs or copies of the
articles. Thank you for your continued interest in the journal and abstract
postings.
A guide for authors is included at the website.
With regards,
Dagmar Fertl
Kitakado, T., C. Lockyer, and A.E. Punt. 2013. A statistical model for
quantifying age-reading errors and its application to the Antarctic minke
whales. Journal of Cetacean Research and Management 13(3):181-190.
Contact e-mail: kitak...@kaiyodai.ac.jp
A statistical method for quantifying age-reading error, i.e. the extent of bias
and inter-reader variability among readers, is introduced. The method assumes
the availability of an independent ‘control reader’ who produces reference ages
for age-reading structures which are also read by additional readers. This
control reader is assumed to provide unbiased or consistently biased age
estimates so that the additional readers’ age-reading outcomes can be
standardised. Linear structures in bias and variance are incorporated in a
conditional probability matrix representing the stochastic nature of
age-determination for each reader. A joint likelihood function for the
parameters related to age-reading bias, variance and nuisance parameters is
defined based on observed age-reading outcomes from both the control and
additional readers. The method is applied to data for Antarctic minke whales
taken during Japanese commercial (1971/72–1986/87) and scientific (JARPA:
1987/88–2004/05, JARPA II: 2005/06–2010/11) whaling. A total of 250 earplugs
selected according to a predetermined protocol were used in the analyses to
estimate the inter-reader variation for four Japanese readers. One of the
authors acted as the control reader. The Japanese readers and the control
reader differed in terms of both the expected age given the true age, and
variance in age-estimates. The expected age and random uncertainty in age
estimates differed among the Japanese readers, although the two readers in
charge of age-reading for samples taken during Japanese scientific whaling
(JARPA and JARPA II) provided quite similar agereading outcomes. These results
contribute to analyses using catch-at-age data for this species. It should also
be noted that the model and approach in this paper can be applied to
populations other than the Antarctic minke whales, if a control reader is
available, even retrospectively.
********
Félix, F., and B. Haase. 2013. A note on the northernmost record of the
Antarctic minke whale (Balaenoptera bonaerensis) in the Eastern Pacific.
Journal of Cetacean Research and Management 13(3):191-194.
Contact e-mail: fefeli...@hotmail.com
In this study the first record of the Antarctic minke whale (Balaenoptera
bonaerensis) in Ecuador (2°7.35’S, 80°45.7’W) is presented. It was a single
stranding of a calf of 3.43m in length. The species was identified based on
morphological characteristics such as the number and colour of baleen plates,
the number and extension of ventral grooves, lack of white flipper patch and
the waved greyish light colouration pattern on the flanks, among others.
Although only a handful of records exist of this species in the Eastern
Pacific, it confirms that the breeding area of this species at least reaches
the equator in this region.
********
Koh, H.S., J.E. Jo, N.H. Ahn, J.J. Lee, K.S. Kim, and C.W. Jin. 2013.
Preliminary study on genetic differences between two species of finless
porpoises, genus Neophocaena, with lack of genetic divergence between two
subspecies of the narrow-ridged finless porpoise, N. asiaeorientalis:
cytochrome b sequence analyses. Journal of Cetacean Research and Management
13(3):195-199.
Contact e-mail: sysk...@chungbuk.ac.kr
Using samples from bycaught finless porpoises, cytochrome b sequences were
analysed and phylogenetic trees were constructed. The aims were to: (1)
determine genetic divergences within the genus Neophocaena; (2) examine
interspecific divergences between N. asiaeorientalis and N. phocaenoides; and
(3) examine intraspecific divergence between N.a. asiaeorientalis and N.a.
sunameri. For this purpose, complete cytochrome b sequences for 12 N.a.
sunameri specimens, collected from fishery markets at Pohang in southeastern
Korea, were obtained, and these sequences were compared to the corresponding
partial (402bp) and complete (1,140bp) sequences of Neophocaena, obtained from
GenBank. From a maximum likelihood tree with the partial sequences of the two
Neophocaena species, two clades were detected, corresponding to the two
species, with average genetic distance of 1.64%, four fixed site differences
(1.00%), and a Gst value of 0.64, although we did not examine the specimens
from Southeast Asia and contiguous South China Sea. Furthermore, from the
complete sequences, we recognised a lack of genetic divergence between the two
subspecies of N. asiaeorientalis, with a Gst value of 0.06 and two pairs of
identical sequences between them, indicating that our results do not support
current subspecies classification. Thus, we newly found that our cytochrome b
sequencing results are useful for the examination of interspecific and
intraspecific divergences in Neohpocaena, although further genetic analyses
with additional specimens of Neophocaena across its distributional range are
necessary to confirm the findings in this study.
********
Pitchford, J.L., B.J.S. Serafin, D. Shannon, A.T. Coleman, and M. Solangi.
2013. An analysis of historical bottlenose dolphin (Tursiops truncatus)
strandings in the Mississippi Sound, USA using classification and regression
trees (CART). Journal of Cetacean Research and Management 13(3):201-209.
Contact e-mail: jpitchf...@imms.org
Trends in bottlenose dolphin (Tursiops truncatus) strandings can be used to
examine several factors associated with mortality and life history and are
essential for detecting unusual mortality events (UMEs). This study
characterised stranding trends in the Mississippi Sound (MS) region of the
northern Gulf of Mexico (GoM) from 1996–2009 using kernel density estimation
(KDE) and classification and regression tree (CART) analysis. An annual mean of
26.1 strandings (n = 14), SD = 13.7, 95% CI [18.2, 34.0] and a peak in
strandings during spring (March–May) were evident from our analyses. Neonates
stranded almost exclusively in spring indicating that this is the dominant
breeding and calving season in this area. Spatial distributions revealed that
the majority of dolphins stranded along central and western portions of the MS
Sound near Gulfport, MS and on Ship Island during the spring and summer months,
but were more often found in the eastern MS Sound during winter and autumn. Our
CART analyses indicated that 1996, which contained a declared UME, was
anomalous from other years as the number of adult, sub-adult and juvenile
strandings was relatively high during the autumn and winter. Further, our
analyses showed that the location of those strandings on Ship Island in autumn
and winter was unique from all other years in the historical record. These
results represent historical conditions that can be used as a baseline for
future studies of the effects of environmental disturbances, including UMEs, in
MS. This research also demonstrates the versatility and usefulness of CART for
describing historical trends, detecting departures from the norm and explaining
UMEs within the framework of a single analysis. This approach represents an
objective assessment tool that could be used to assist governmental agencies
with determining the onset of a UME and could help support or refute the cause
of these events.
********
Benmessaoud, R., M. Cherif, and N. Bejaoui. 2013. Baseline data on abundance,
site fidelity and association patterns of common bottlenose dolphins (Tursiops
truncatus) off the northeastern Tunisian coast (Mediterranean Sea). Journal of
Cetacean Research and Management 13(3):211-219.
Contact e-mail: benmessaoud_ri...@yahoo.fr
The common bottlenose dolphin has been studied intensively in numerous
locations around the world but very little is known about this species along
the South Mediterranean Basin. In this study, the temporal distribution of
dolphins, group dynamics, site fidelity and association patterns of common
bottlenose dolphins along the northeastern coastal waters of Tunisia was
assessed through mark recapture photo-identification techniques. Prior to this
study, no research has focused on bottlenose dolphins within these waters,
despite the potential for human impacts on this species. A total of 718h of
boat-based observations, spanning 284 days, were spent at sea between August
2008 and July 2010. During this period, 253h were spent in direct observation
of 317 groups of common bottlenose dolphins. Bottlenose dolphins were observed
in all seasons, although seasonality was evident, with more encounters during
the summer. Photo-identification studies show that 43 individuals used the
northeastern coast of Tunisia on a regular basis, while others were present
less often. Based on a social structure analysis it was possible to
discriminate different communities related with the spatial distribution of the
sightings (Zembra island, Hammamet, Kelibia and Galite island).
********
Towers, J.R., C.J. McMillan, M. Malleson, J. Hildering, J.K.B. Ford, and G.M.
Ellis. 2013. Seasonal movements and ecological markers as evidence for
migration of common minke whales photo-identified in the eastern North Pacific.
Journal of Cetacean Research and Management 13(3):221-229.
Contact e-mail: jrtow...@gmail.com
In the eastern North Pacific Ocean, common minke whales (Balaenoptera
acutorostrata) are widespread but encountered relatively infrequently. It is
generally believed that they make annual migrations between higher latitudes in
the summer and lower latitudes in the winter; however, in some temperate
coastal regions where common minke whales have been sighted year-round they
have been referred to as resident. To determine movement patterns of common
minke whales found in coastal waters of British Columbia and Washington we
examined photo-identification data that were collected opportunistically from
2005–12. These data were from four non-overlapping areas between 48°N and 53°N.
Despite year-round search efforts, common minke whales were only encountered
between April and October. Most of the 44 unique individuals identified in 405
encounters displayed fidelity to areas both within and among years. Five of
these whales made relatively large-scale intra-annual movements between areas
on six occasions. They were documented to move up to 424km in a northerly
direction in spring and up to 398km in a southerly direction in autumn. The
seasonal patterns of these movements provide new insights into the foraging
ranges and migrations of the individuals. Ecological markers provide evidence
that the common minke whales photographed undertake annual long distance
migrations. Scars believed to be from cookiecutter shark (Isistius
brasiliensis) bites were observed on 43 individuals and the majority of whales
documented with good quality images each year had acquired new scars since the
previous year. Furthermore, the commensal barnacle Xenobalanus globicipitis was
observed on three individuals. Since these sharks and barnacles are from
relatively warm waters, it can be inferred that they interacted with the common
minke whales at lower latitudes. These findings may have important implications
for the definition and management of common minke whale stocks and/or
populations in the eastern North Pacific.
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