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Heaviside's dolphin (Cephalorhynchus heavisidii) is a coastal delphinid with a limited inshore distribution off the west coast of southern Africa. Knowledge of its habitat usage is an essential precursor to assessing its potential vulnerability to fisheries interactions. Six Heaviside's dolphins (1 male and 5 females) were fitted with satellite-linked transmitters in 2004, and tracked for up to 54 days. The 5 tags fitted to female dolphins transmitted continuously, allowing for analysis of movements at a fine temporal scale. Four dolphins showed an initial avoidance of the capture site by moving over a wider area in the first 2-5 days posttagging than later in the deployment period. All dolphins had used their full home ranges (determined as 100% minimum convex polygons) 5-20 days before tag failure, suggesting measured home ranges were stable at this temporal scale. Home-range estimates using local convex hulls ranged from 301.9 to 1,027.6 [km.sup.2] (90% isopleths) and 875.9 to 1,989.6 [km.sup.2] using the 100% isopleths and scaled positively with body size but varied in shape, usage, and number of core-use areas. Although the distance from shore and depth at which individual dolphins moved varied greatly, all dolphins showed a strong onshore-offshore diurnal movement pattern, generally being closest inshore between 0600 h and noon, and farthest offshore between 1500 h and 0500 h. This pattern is assumed to be related to the movements of their principal prey, juvenile shallow-water hake (Merluccius capensis), which migrate into the upper water column at night. Movements inshore may be associated with rest, socializing, and predator avoidance. Key words: Argos, Cephalorhynchus heavisidii, Heaviside's dolphin, home range, satellite telemetry

Abstract: The Indian Ocean humpback dolphin was recently uplisted to ‘Endangered’ in the recent South African National Red List assessment. Abundance estimates are available from a number of localized study sites, but knowledge of movement patterns and population linkage between these sites is poor. A national research collaboration, the SouSA project, was established in 2016 to address this key knowledge gap. Twenty identification catalogues collected between 2000 and 2016 in 13 different locations were collated and compared. Photographs of 526 humpback dolphins (all catalogues and photos) were reduced to 337 individuals from 12 locations after data selection. Of these, 90 matches were found for 61 individuals over multiple sites, resulting in 247 uniquely, well‐marked humpback dolphins identified in South Africa. Movements were observed along most of the coastline studied. Ranging distances had a median value of 120 km and varied from 30 km up to 500 km. Long‐term site fidelity was also evident in the data. Dolphins ranging along the south coast of South Africa seem to form one single population at the western end of the species' global range. Current available photo‐identification data suggested national abundance may be well below previous estimates of 1000 individuals, with numbers possibly closer to 500. Bearing in mind the poor conservation status of the species in the country, the development of a national Biodiversity Management Plan aimed at ensuring the long‐term survival of the species in South Africa is strongly recommended. At the same time, increased research efforts are essential, particularly to allow for an in‐depth assessment of population numbers and drivers of changes therein. The present study clearly indicates the importance of scientific collaboration when investigating highly mobile and endangered species. [ABSTRACT FROM AUTHOR]

The knowledge embedded in organizational processes has been difficult to codify and make available to other members who need access to this knowledge either because they perform complementary processes or may need to take over the processes in question. Previous approaches to the codification of such knowledge have recognized the difficulties of capturing the context within which the knowledge is utilized. In this design-science based work, the authors propose a work process knowledge template (WPKT) which follows a systems' approach to capturing work processes that balances complexity of the template with capturing relevant context. The template was pilot tested during development, and empirically evaluated for usability, ease of use and learnability in multiple real world settings. [ABSTRACT FROM AUTHOR]

Cetaceans, occupying the top levels in marine food chains, are vulnerable to elevated levels of potentially toxic trace elements, such as aluminium ( Al), mercury ( Hg) and nickel ( Ni). Negative effects associated with these toxic metals include infection by opportunistic microbial invaders. To corroborate the link between the presence of cutaneous fungal invaders and trace element levels, skin samples from 40 stranded false killer whales ( FKWs) were analysed using culture techniques and inductively coupled plasma-mass spectroscopy. Twenty-two skin samples yielded 18 clinically relevant fungal species. While evidence for bioaccumulation of Hg in the skin of the FKWs was observed, a strong link was found to exist between the occurrence of opportunistic fungal invaders and higher Al : Se and Al : Zn ratios. This study provides indications that elevated levels of some toxic metals, such as Al, contribute to immunotoxicity rendering FKWs susceptible to colonization by cutaneous opportunistic fungal invaders. [ABSTRACT FROM AUTHOR]

Heaviside's dolphins, Cephalorhynchus heavisidii, are endemic to southwestern Africa, where they are exposed to unknown levels of anthropogenic threats, including inshore set netting. Using photo-ID data collected over 3 yr on the west coast of South Africa, we calculated Chapman's-modified Petersen estimates of the number of distinctive individuals at three spatial scales. Sample sizes were small and recapture rates low resulting in high variance. Total population abundance was extrapolated from the proportion of well-marked animals in the population (14%–17%) with between-year estimates adjusted for mortality using data from Commerson's dolphin. The total population size was calculated as 527 animals (CV = 0.35, CI 272–1,020) in the 1999 study area (20 km of coastline, within season), 3,429 animals (CV = 0.36, CI 1,721–6,828) in the central study area (150 km of coastline, 3 yr), and 6,345 animals (CV = 0.26, CI 3,573–11,267) in the full study area (390 km of coastline, 2 yr). Dolphins fitted with satellite transmitters varied in their use of the inshore photographic study area from 39.5% to 94.7% of transmission days (38–51 total). Given the known or suspected biases in the data, these abundance estimates are likely to be biased downward. [ABSTRACT FROM AUTHOR]

The bulk ore carrier Apollo Seasank near Dassen Island, South Africa, on 20 June 1994 during a period of winter storms. Approximately 10 000 African (Jackass) Penguins Spheniscus demersuswere oiled, collected and transported to the SANCCOB rescue centre; 5213 were released after cleaning, 4076 with flipper bands. We believe that most of the penguins oiled during this incident reached an island or the mainland alive, and that there was no mass mortality in the wild at the time of the oil spill. Birds from all parts of the breeding range were oiled, but most were from Robben and Dassen Islands. The overwhelming majority of released birds made the transition from the rescue centre to the wild successfully; 2652 had been resighted at breeding colonies within two years of their release; the cumulative number of birds was increasing steadily and an asymptote had not been reached by August 1996. There was a wide dispersal of released penguins, with recoveries and resightings over 1800 km of coastline between Algoa Bay and Walvis Bay. [ABSTRACT FROM AUTHOR]

Objective:Maintenance of normal glucose tolerance is achieved in subjects with a wide range of insulin sensitivity. It follows, therefore, that the body must possess a sensor mechanism that assesses the body's sensitivity to insulin and appropriately adjusts the secretion of insulin to maintain normal glucose homeostasis. We evaluated the relation between insulin action and insulin secretion.Methods:Euglycemic hyperinsulinemic clamp (1 mU/kg · minute) and hyperglycemic clamp (+ 125 mg/dL) studies were performed in 32 non-obese women with normal oral glucose tolerance tests. The subjects were stratified into quartiles based upon their insulin-mediated rate of glucose uptake during the eulgycemic insulin clamp.Results:Total body glucose disposal varied threefold, ranging from 4.00 to 11.18 mg/kg · minute. A significant inverse relation (r = -0.50, P < .01) was noted between the rate of total body insulin-mediated glucose disposal (insulin clamp) and the total plasma insulin response during the hyperglycemic clamp. Women in the lowest quartile of insulin sensitivity (mean glucose uptake 5.07 ± 0.20 mg/kg · minute) had the highest plasma insulin response during the hyperglycemic clamp (109 ± 20 μU/mL). In contrast, women in the highest quartile of insulin sensitivity (glucose uptake 9.90 ± 0.38 mg/kg · minute) had the lowest plasma insulin response during the hyperglycemic clamp (55 ± 16 μU/mL; P < .001 versus the lowest quartile).Conclusions:These results demonstrate that among subjects with normal glucose tolerance, there exists a large variation in both insulin-mediated glucose uptake and pancreatic insulin secretion. Nonetheless, normal glucose tolerance is maintained because of a finely regulated balance, which couples the demand for insulin secretion by the pancreatic beta cells to the level of whole-body insulin sensitivity. [ABSTRACT FROM PUBLISHER]