scholarly journals Transit station or destination? Attendance patterns, movements and abundance estimate of humpback whales off west South Africa from photographic and genotypic matching

2011 ◽  
Vol 33 (3) ◽  
pp. 353-373 ◽  
Author(s):  
J Barendse ◽  
PB Best ◽  
M Thornton ◽  
SH Elwen ◽  
HC Rosenbaum ◽  
...  
Keyword(s):  
South Africa ◽  
Humpback Whales ◽  
Abundance Estimate ◽  
Attendance Patterns ◽  
Transit Station

scholarly journals Encounter rates and abundance of humpback whales (Megaptera novaeangliae) in Gerlache and Bransfield Straits, Antarctic Peninsula

2020 ◽  
pp. 107-111
Author(s):  
Eduardo R. Secchi ◽  
Luciano Dalla Rosa ◽  
Paul G. Kinas ◽  
Raquel F. Nicolette ◽  
Anne N. M. Rufino ◽  
...  
Keyword(s):  
Antarctic Peninsula ◽  
Distance Sampling ◽  
Austral Summer ◽  
Humpback Whales ◽  
Encounter Rate ◽  
Encounter Rates ◽  
Abundance Estimate ◽  
Bransfield Strait ◽  
Distance Data ◽  
The Difference

During the austral summer of 2006, the Projeto Baleias/Brazilian Antarctic Program (PROANTAR) conducted ship surveys for estimating whale encounter rates and abundance in Gerlache and Bransfield Straits, westward of the Antarctic Peninsula (edge between IWC Areas I and II). The encounter rate was higher in the Bransfield Strait (0.32 groups n. mile–1; 95% CI: 0.26–0.39) than in the Gerlache Strait (0.24 groups n. mile–1; 95% CI: 0.13–0.44), though the difference was not statistically evident. An abundance estimate using conventional distance sampling methods was computed only for the Bransfield Strait. The perpendicular distance data was best fitted by the half-normal model without adjustments. Derived abundance for the surveyed area was 865 humpback whales (95% CI = 656–1,141; CV = 14.13). This area represents only a small fraction of the Stock G feeding ground.

scholarly journals Abundance of East coast Australian humpback whales (Megaptera novaeangliae) in 2005 estimated using multi-point sampling and capture-recapture analysis

2020 ◽  
pp. 253-259
Author(s):  
David A. Paton ◽  
Lyndon Brooks ◽  
Daniel Burns ◽  
Trish Franklin ◽  
Wally Franklin ◽  
...  
Keyword(s):  
East Coast ◽  
Megaptera Novaeangliae ◽  
Humpback Whales ◽  
Migration Route ◽  
Closed Population ◽  
Breeding Stock ◽  
Abundance Estimate ◽  
Abundance Estimates ◽  
Capture Recapture ◽  
Near Extinction

The humpback whales (Megaptera novaeangliae) that migrate along the east coast of Australia were hunted to near extinction during the lastcentury. This remnant population is part of Breeding Stock E. Previous abundance estimates for the east Australian portion of Breeding Stock Ehave been based mainly on land-based counts. Here we present a capture-recapture abundance estimate for this population using photo-identificationdata. These data were collected at three locations on the migration route (Byron Bay – northern migration, Hervey Bay and Ballina – southernmigration) in order to estimate the population of humpback whales that migrated along the east coast of Australia in 2005. The capture-recapturedata were analysed using a variety of closed population models with a model-averaged estimate of 7,041 (95% CI 4,075–10,008) whales.

scholarly journals Song recorded near a super-group of humpback whales on a mid-latitude feeding ground off South Africa

2018 ◽  
Vol 143 (4) ◽  
pp. EL298-EL304 ◽  
Author(s):  
T. Gridley ◽  
M. F. P. Silva ◽  
C. Wilkinson ◽  
S. M. Seakamela ◽  
S. H. Elwen
Keyword(s):  
South Africa ◽  
Humpback Whales ◽  
Feeding Ground

scholarly journals Absolute and relative abundance estimates of Australian east coast humpback whales (Megaptera novaeangliae)

2020 ◽  
pp. 243-252
Author(s):  
Michael J. Noad ◽  
Rebecca A. Dunlop ◽  
David Paton ◽  
Douglas H. Cato
Keyword(s):  
Data Analysis ◽  
East Coast ◽  
Humpback Whales ◽  
Absolute Abundance ◽  
Abundance Estimate ◽  
Abundance Estimates ◽  
Rate Of Increase ◽  
Migratory Population ◽  
Australian Coastline ◽  
Near Extinction

The humpback whales that migrate along the east coast of Australia were hunted to near-extinction in the 1950s and early 1960s. Two independentseries of land-based surveys conducted over the last 25 years during the whales’ northward migration along the Australian coastline havedemonstrated a rapid increase in the size of the population. In 2004 we conducted a survey of the migratory population as a continuation of theseseries of surveys. Two methods of data analysis were used in line with the previous surveys, both for calculation of absolute and relative abundance.We consider the best estimates for 2004 to be 7,090±660 (95% CI) whales with an annual rate of increase of 10.6±0.5% (95% CI) for 1987–2004.The rate of increase agrees with those previously obtained for this population and demonstrates the continuation of a strong post-exploitationrecovery. While there are still some uncertainties concerning the absolute abundance estimate and structure of this population, the rate of annualincrease should be independent of these and highly robust.

Bayesian estimation of humpback whale (Megaptera novaeangliae) population abundance and movement patterns in southeastern Alaska

2012 ◽  
Vol 69 (11) ◽  
pp. 1783-1797 ◽  
Author(s):  
A.N. Hendrix ◽  
J. Straley ◽  
C.M. Gabriele ◽  
S.M. Gende
Keyword(s):  
Deviance Information Criterion ◽  
Information Criterion ◽  
Megaptera Novaeangliae ◽  
Humpback Whales ◽  
Observation Error ◽  
Movement Model ◽  
Abundance Estimate ◽  
High Area ◽  
Rate Of Increase ◽  
Competing Models

We used a mechanistic movement model within a Bayesian framework to estimate survival, abundance, and rate of increase for a population of humpback whales ( Megaptera novaeangliae ) subject to a long-term photographic capture–recapture effort in southeastern Alaska, USA (SEAK). Multiple competing models were fitted that differed in movement, recapture rates, and observation error using deviance information criterion. The median annual survival probability in the selected model was 0.996 (95% central probability interval (CrI): 0.984, 0.999), which is among the highest reported for this species. Movement among areas was temporally dynamic, although whales exhibited high area fidelity (probability of returning to same area of ≥0.75) throughout the study. Median abundance was 1585 whales in 2008 (95% CrI: 1455, 1644). Incorporating an abundance estimate of 393 (95% confidence interval: 331, 455) whales from 1986, the median rate of increase was 5.1% (95% CrI: 4.4%, 5.9%). Although applied here to cetaceans in SEAK, the framework provides a flexible approach for estimating mortality and movement in populations that move among sampling areas.

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