Distribution patterns of east Australian humpback whales (Megaptera novaeangliae) in Hervey Bay, Queensland: a historical perspective

2020 ◽  
Vol 42 (1) ◽  
pp. 16 ◽  
Author(s):  
S. H. Stack ◽  
J. J. Currie ◽  
J. A. McCordic ◽  
A. F. Machernis ◽  
G. L. Olson
Keyword(s):  
Historical Perspective ◽  
Distribution Patterns ◽  
Humpback Whales ◽  
Effective Management ◽  
Target Species ◽  
Spatial And Temporal Patterns ◽  
Educational Value ◽  
Using Data ◽  
Sustained Recovery ◽  
Residency Time

Tourism activities are expanding in both terrestrial and marine environments, which can have detrimental effects on the target species. Balancing the amount of disturbance a population of animals receives against the educational value of tourism requires localised research and adaptive management. This study examined the distribution of humpback whales within Hervey Bay, Queensland, using data spanning 2004–16, just before the implementation of a commercial ‘swim-with-whales’ program. Spatial and temporal patterns of humpback whale calves were of particular interest given that they are more vulnerable to human-related disturbances than other group types. We found that humpback whales displayed a distinct spatial segregation in Hervey Bay based on pod composition. Most whales displayed a residency time of two to three days, with females having a somewhat shorter residency time than males. These findings suggest that humpback whales in Hervey Bay not only display temporal segregation dependent on maturation and reproductive status, but fine-scale spatial distribution based on pod composition. Understanding habitat preference and patterns of habitat use of humpback whales in Hervey Bay is critical for effective management of the newly sanctioned swim-with-whale tourism in Hervey Bay and the sustained recovery of humpback whales in this region.

scholarly journals Estimated Abundances of Cetacean Species in the Northeast Atlantic from Norwegian Shipboard Surveys Conducted in 2014–2018

2020 ◽  
Vol 11 ◽  
Author(s):  
Deanna Leonard ◽  
Nils Øien
Keyword(s):  
Barents Sea ◽  
Humpback Whales ◽  
Physeter Macrocephalus ◽  
Sperm Whales ◽  
Target Species ◽  
Independent Observer ◽  
Southern Boundary ◽  
Norwegian Sea ◽  
Northeast Atlantic ◽  
Fin Whales

A ship-based mosaic survey of Northeast Atlantic cetaceans was conducted over a 5-year period between 2014–2018. The area surveyed extends from the North Sea in the south (southern boundary at 53oN), to the ice edge of the Barents Sea and the Greenland Sea. Survey vessels were equipped with 2 independent observer platforms that detected whales in passing mode and applied tracking procedures for the target species, common minke whales (Balaenoptera acutorostrata acutorostrata). Here we present abundance estimates for all non-target species for which there were sufficient sightings. We estimate the abundance of fin whales (Balaenoptera physalus) to be 11,387 (CV=0.17, 95% CI: 8,072–16,063), of humpback whales (Megaptera novaeangliae) to be 10,708 (CV=0.38, 95% CI: 4,906–23,370), of sperm whales (Physeter macrocephalus) to be 5,704 (CV=0.26, 95% CI: 3,374–9,643), of killer whales (Orcinus orca) to be 15,056 (CV=0.29, 95% CI: 8,423–26,914), of harbour porpoises (Phocoena phocoena) to be 255,929 (CV=0.20, 95% CI: 172,742–379,175), dolphins of genus Lagenorhynchus to be 192,767 (CV=0.25, 95% CI: 114,033–325,863), and finally of northern bottlenose whales (Hyperoodon ampullatus) to be 7,800 (CV=0.28, 95% CI: 4,373–13,913). Additionally, our survey effort in the Norwegian Sea in 2015 contributed to the 6th North Atlantic Sightings Survey (NASS) and the survey was extended into the waters north and east of Iceland around Jan Mayen island. This NASS extension, along with our Norwegian Sea survey in 2015, was used to estimate the abundance of fin whales, humpback whales, and sperm whales. All estimates presented used mark-recapture distance sampling techniques and were thus corrected for perception bias. Our estimates do not account for additional variance due to distributional shifts between years or biases due to availability or responsive movement.

Habitat segregation by female humpback whales in Hawaiian waters: avoidance of males?

Behaviour ◽  
2014 ◽  
Vol 151 (5) ◽  
pp. 613-631 ◽  
Author(s):  
Alison S. Craig ◽  
Louis M. Herman ◽  
Adam A. Pack ◽  
James O. Waterman
Keyword(s):  
Swimming Speed ◽  
Significant Positive Correlation ◽  
Humpback Whales ◽  
Shallow Waters ◽  
Habitat Segregation ◽  
Low Latitude ◽  
Energetic Costs ◽  
Using Data ◽  
Number Of Males ◽  
Winter Breeding

Humpback whales congregate annually in low-latitude winter breeding and calving grounds. While on these grounds, females with a dependent calf (‘maternal females’) are sometimes closely attended by one or more male escorts. Using data collected from a shore-based observation platform in the Hawaiian Islands, we tested the hypothesis that the spatial distribution of maternal females is driven primarily by avoidance of males. As predicted, we found that (1) pods containing a calf occurred in significantly shallower water than pods that did not contain a calf, (2) unescorted maternal females occurred in significantly shallower water than escorted maternal females, (3) the number of males escorting a female decreased significantly with decreasing water depth, and (4) the swimming speed of maternal females increased as a function of male presence, with escorted females travelling significantly more rapidly than unescorted females and a significant positive correlation between swimming speed and number of escorts. We suggest that maternal females incur increased energetic costs when escorted by males and consequently position themselves in shallow waters to reduce the likelihood of unwanted male attention.

Critical Success Factors and Outcomes of Market Knowledge Management

2010 ◽  
Vol 6 (3) ◽  
pp. 1-21 ◽  
Author(s):  
Subramanian Sivaramakrishnan ◽  
Marjorie Delbaere ◽  
David Zhang ◽  
Edward Bruning
Keyword(s):  
Knowledge Management ◽  
Business Performance ◽  
Critical Success Factors ◽  
Success Factors ◽  
Future Research ◽  
Effective Management ◽  
Market Knowledge ◽  
Information Technology Adoption ◽  
Critical Success ◽  
Using Data

In this paper, the authors examine critical success factors and outcomes of market knowledge management, which is the management of knowledge pertaining to a firm’s customers, competitors, and suppliers. Using data collected from 307 managers in 105 businesses across Canada, the authors show that a firm’s extent of information technology adoption, its analytical capabilities, and market orientation are critical success factors for the firm’s market knowledge management. An important outcome of market knowledge management is the organization’s financial performance, mediated by customer satisfaction and customer loyalty. Results of this study indicate that superior business performance depends not only on the effective management of knowledge, but also on what type of knowledge is managed. Finally, implications of results and avenues for future research are discussed.

Site fidelity and residence times of humpback whales (Megaptera novaeangliae) on the Brazilian coast

2012 ◽  
Vol 92 (8) ◽  
pp. 1783-1791 ◽  
Author(s):  
Clarêncio G. Baracho-Neto ◽  
Elitieri Santos Neto ◽  
Marcos R. Rossi-Santos ◽  
Leonardo L. Wedekin ◽  
Mariana C. Neves ◽  
...  
Keyword(s):  
Residence Time ◽  
Site Fidelity ◽  
Megaptera Novaeangliae ◽  
Humpback Whales ◽  
Brazilian Coast ◽  
Northern Coast ◽  
Occupancy Rate ◽  
Breeding Grounds ◽  
Minimum Number ◽  
Using Data

Humpback whales (Megaptera novaeangliae) migrate between their feeding grounds, located in high latitudes, and their breeding grounds, located in low latitudes, exhibiting certain levels of site fidelity to their migratory destinations. The residence time, also known as occupancy rate, can be defined as the minimum number of days that those individuals remained in the same area. In this paper, site fidelity and residence time of humpback whales that breed off the northern coast of Bahia, Brazil were investigated. Data were collected between 2000 and 2009 on-board research cruises and whale watching vessels. This paper also studies possible differences between males and females with respect to site fidelity off the Brazilian coast, using data collected since 1989. A total of 841 whales were photo-identified. The vast majority of the whales (96%, N = 809) were seen only once in the studied area, while 4% (32 individuals) were seen twice. Most of the resights occurred within the same season (72%, N = 23), while 9 resights (28%) occurred in different years. None of the individuals were seen more than twice. The average site fidelity rate was 1% and the occupancy rate varied from one up to 21 days (mean = 5.3; SD = 5.4, N = 23).

Spatial patterns and habitat associations of Fagaceae in a hill dipterocarp forest in Ulu Gadut, West Sumatra

2008 ◽  
Vol 24 (05) ◽  
pp. 535-550 ◽  
Author(s):  
Sen Nishimura ◽  
Tsuyoshi Yoneda ◽  
Shinji Fujii ◽  
Erizal Mukhtar ◽  
Mamoru Kanzaki
Keyword(s):  
Random Distribution ◽  
Distribution Patterns ◽  
Habitat Associations ◽  
Target Species ◽  
Dipterocarp Forest ◽  
Median Distance ◽  
Preferred Habitat ◽  
West Sumatra ◽  
Hill Dipterocarp Forest ◽  
Habitat Variables

Abstract:Spatial distribution patterns and habitat associations of Fagaceae species in a Fagaceae-codominated hill forest in Sumatra were investigated. Ten Fagaceae species believed to be zoochorous (animal-dispersed seed) and five codominant canopy and emergent anemochorous (wind-dispersed seed) species from Anacardiaceae and Dipterocarpaceae were studied. Five Fagaceae species and all codominant anemochorous species were significantly aggregated while the other five Fagaceae species showed a random distribution pattern. The median distance of small saplings from the nearest reproductively mature tree tended to be shorter for aggregated species than spatially random species. This implied that some Fagaceae species dispersed over longer distances than anemochorous species. Relationships between four habitat variables and distribution of the target species were examined with torus-translation tests. ThreeQuercusand oneLithocarpusspecies showed positive habitat associations. TwoQuercusspecies aggregated at the preferred habitat, but the others were randomly distributed. Thus tree species with specific habitat preference do not only aggregate at the preferred habitat. The three ridge-specialistQuercusspecies showed gradual changes in habitat association, which could reflect avoidance of competition among the species. Most of theLithocarpusspecies showed little correlation with habitat variables. Coexistence of the threeQuercusspecies partly reflected subtle differences in topographical preferences. Distribution of five of the sixLithocarpusspecies was unrelated to topography, so other mechanisms must be sought to account for the maintenance of coexistence in this species-rich genus.

scholarly journals POTENTIAL FISHING GROUND MAPPING BASED ON GIS HOTSPOT MODEL AND TIME SERIES ANALYSIS: A CASE STUDY ON LIFT NET FISHERIES IN SERIBU ISLAND

2017 ◽  
Vol 9 (1) ◽  
pp. 337-356
Author(s):  
Andi Alamsyah Rivai ◽  
Vincentius P. Siregar ◽  
Syamsul B. Agus ◽  
Hiroki Yasuma
Keyword(s):  
Time Series ◽  
Fisheries Management ◽  
Fishing Ground ◽  
Effective Management ◽  
Target Species ◽  
Fishing Activity ◽  
Fishing Season ◽  
Spatio Temporal ◽  
West Monsoon

Information on the spatial and temporal of fishing activity can optimize a fisheries management and increase their economical and biological benefit. For effective management and good understanding of fishing activities, information about fishing ground is crucial. In this study, we aimed to analyze the spatio-temporal of lift net fisheries in Kepulauan Seribu by analyzing their fishing season, investigating their hotspot of fishing ground using GIS-based hotspot model, and mapping the potential fishing ground of each target species. We found that anchovy and scad could be caught throughtout the year, while sardine and squid had high fishing season in west monsoon. Hotspot of fishing ground of lift net fisheries in Kepulauan Seribu waters generally was concentrated around Lancang Island and in southern part of Kotok Island. Potential fishing ground for sardines was located in around Lancang Island on west monsoon. Squids were highly distributed around Lancang Island in December to January and around Lancang and Rambut Islands in November. Anchovy and scad had more potential fishing ground in around Kepulauan Seribu waters.  Keywords: fishing ground, lift net, hotspot, fishing season 

scholarly journals Distribution patterns of chaetognata, polychaeta, pteropoda and salpidae off south georgia and south orkney islands

2010 ◽  
Vol 58 (4) ◽  
pp. 287-298 ◽  
Author(s):  
Alina María Crelier ◽  
José Roberto Dadon ◽  
Hernán G. Isbert-Perlender ◽  
Daniel Eduardo Nahabedian ◽  
María Cristina Daponte
Keyword(s):  
Distribution Patterns ◽  
Polar Front ◽  
Species Density ◽  
The South ◽  
South Georgia ◽  
Orkney Islands ◽  
Pattern Frequency ◽  
South Orkney Islands ◽  
Circumpolar Current ◽  
Using Data

The distribution pattern, frequency and density (ind./1000 m) of different mesozooplankton species from the South Georgia Islands, South Orkney Islands and the Weddell-Scotia Confluence were analyzed using data obtained in 1994. The maximum densities of the species found were: Eukrohnia hamata (5330), Sagitta gazellae (1052), Clione limacina antarctica (450), Spongiobranchaea australis (375), Clio sulcata (100), Limacina helicina (4076 x 10³), Limacina retroversa (71 x 10(4)), Pelagobia longicirrata (29170), Rhynchonereella bongraini (117), Tomopteris carpenterii (26), Tomopteris planktonis (498), Tomopteris septentrionales (498) and Salpa thompsoni (189). Species density and frequency decreased from South Georgia to the South Orkney Islands, recording intermediate values at the Weddell-Scotia Confluence. Species density in the South Orkney area seemed to be limited by variations in temperature and salinity. The southern area around South Georgia showed the highest density of species, probably due to the influence of the Southern Front of the Antarctic Circumpolar Current. The presence of species characteristic of sub-Antarctic waters such as L. retroversa in the Confluence area could be related to the southward movements of eddies that originate in the Polar Front.

scholarly journals Identifying and Predicting the Geographical Distribution Patterns of Oncomelania hupensis

2019 ◽  
Vol 16 (12) ◽  
pp. 2206 ◽  
Author(s):  
Niu ◽  
Li ◽  
Qiu ◽  
Xu ◽  
Huang ◽  
...  
Keyword(s):  
Land Surface ◽  
Vegetation Index ◽  
Normalized Difference Vegetation Index ◽  
Distribution Patterns ◽  
Oncomelania Hupensis ◽  
Spatial And Temporal Patterns ◽  
Jianghan Plain ◽  
Coverage Area ◽  
Digital Elevation ◽  
Elevation Model

Schistosomiasis is a snail-borne parasitic disease endemic to the tropics and subtropics, whose distribution depends on snail prevalence as determined by climatic and environmental factors. Here, dynamic spatial and temporal patterns of Oncomelania hupensis distributions were quantified using general statistics, global Moran’s I, and standard deviation ellipses, with Maxent modeling used to predict the distribution of habitat areas suitable for this snail in Gong’an County, a severely affected region of Jianghan Plain, China, based on annual average temperature, humidity of the climate, soil type, normalized difference vegetation index, land use, ditch density, land surface temperature, and digital elevation model variables; each variable’s contribution was tested using the jackknife method. Several key results emerged. First, coverage area of O. hupensis had changed little from 2007 to 2012, with some cities, counties, and districts alternately increasing and decreasing, with ditch and bottomland being the main habitat types. Second, although it showed a weak spatial autocorrelation, changing negligibly, there was a significant east–west gradient in the O. hupensis habitat area. Third, 21.9% of Gong’an County’s area was at high risk of snail presence; and ditch density, temperature, elevation, and wetting index contributed most to their occurrence. Our findings and methods provide valuable and timely insight for the control, monitoring, and management of schistosomiasis in China.

Spatial distribution patterns, abundance and population structure of deep-sea crab Chaceon macphersoni, based on complementary analyses of trap and trawl data

2013 ◽  
Vol 64 (6) ◽  
pp. 507 ◽  
Author(s):  
Johan C. Groeneveld ◽  
Bernadine I. Everett ◽  
Sean T. Fennessy ◽  
Stephen P. Kirkman ◽  
Jorge Santos ◽  
...  
Keyword(s):  
Population Structure ◽  
Deep Sea ◽  
Distribution Patterns ◽  
Marine Species ◽  
Austral Spring ◽  
Mean Size ◽  
Spatio Temporal ◽  
Catch Rates ◽  
Using Data ◽  
Hard Substrata

Marine species such as deep-sea geryonid crabs often exhibit high spatio-temporal variability in abundance and size over depth, substratum type and season, therefore data collected from a single gear type may not represent the whole population. Complementary data from trawl (soft substratum) and trap (hard substratum) fisheries were analysed within a general linear modelling (GLM) framework to assess distribution, abundance and population structure of Chaceon macphersoni off eastern South Africa. Catch rates, mean size, maturation size and sex ratio were modelled relative to year, month, depth, latitude and gear effects. Trap and trawl analyses indicated higher abundance as depth increased up to 500 m, and during the austral spring and summer. The mean size of crabs remained constant at all depths sampled, and sex ratios were skewed towards females. Females were smaller than males, and achieved maturity at a smaller size. A standardised index based on trawl data (1988–2010) showed a long-term decline in abundance, with some recovery after 2002, whereas the trap index showed recent local depletions on hard substrata. Using data from two gear types confirmed broad gradients in abundance, but also emphasised subtle trends, such as local depletions on hard substrata, that would not have been apparent from trawl data only.

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