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Journal articles on the topic "Cape fur seal"
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Strydom, Zanri, Lauren J. Waller, Mark Brown, Hervé Fritz, Kevin Shaw, and Jan A. Venter. "Factors that influence Cape fur seal predation on Cape gannets at Lambert’s Bay, South Africa." PeerJ 10 (June 13, 2022): e13416. http://dx.doi.org/10.7717/peerj.13416.
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Seabird populations experience predation that can impact their breeding density and breeding success. The Cape gannet Morus capensis is endemic to the Benguela upwelling ecosystem and is classified as Endangered by the IUCN. They are affected by several threats, including predation by the Cape fur seal Arctocephalus pusillus pusillus. Many fledglings succumb to predation during their maiden flight across waters around the island. To curb predation, the selective culling of individual predatory seals was implemented in 2014, 2015, and 2018. Our first study objective was to determine if selective culling of Cape fur seals significantly reduced predation probability on Cape gannets. We tested whether predation probability in 2014, 2015, and 2018 was affected by fish biomass, gannet fledgling numbers, and/or the presence/absence of selective culling. Our second objective was to determine what led to fluctuations in Cape fur seal predation on Cape gannet fledglings between 2007 and 2018. We tested whether fish biomass and the amount of Cape gannet fledglings in the water affected predation probability on the fledglings. Results indicated that selective culling reduced predation within years. We found that with both increased fledgling numbers and increased fish biomass, seal predation probability was reduced. This suggests that a sustainable way to promote the conservation of Cape gannets would be to increase food availability for both the Cape fur seals and Cape gannets. Our findings, collectively with the global trend of the declining Cape gannet population and their endemism, provide reasons advocating for the conservation of the food resources of both the Cape fur seal and the Cape gannet in the Benguela system.
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Shaughnessy, Peter D., Jane McKenzie, Melanie L. Lancaster, Simon D. Goldsworthy, and Terry E. Dennis. "Australian fur seals establish haulout sites and a breeding colony in South Australia." Australian Journal of Zoology 58, no. 2 (2010): 94. http://dx.doi.org/10.1071/zo10017.
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Australian fur seals (Arctocephalus pusillus doriferus) breed on Bass Strait islands in Victoria and Tasmania. They have been recorded in South Australia (SA) for many years as non-breeding visitors and on Kangaroo Island frequently since 1988, mostly in breeding colonies of the New Zealand fur seal (A. forsteri) which is the most numerous pinniped in SA. Australian fur seals have displaced New Zealand fur seals from sections of the Cape Gantheaume colony on Kangaroo Island. North Casuarina Island produced 29 Australian fur seal pups in February 2008. Australian fur seal pups were larger than New Zealand fur seal pups in the same colony and have been identified genetically using a 263-bp fragment of the mitochondrial DNA control region. North Casuarina Island has been an important breeding colony of New Zealand fur seals, but pup numbers there decreased since 1992–93 (contrary to trends in SA for New Zealand fur seals), while numbers of Australian fur seals there have increased. This study confirms that Australian fur seals breed in SA. The two fur seal species compete for space onshore at several sites. Australian fur seals may compete for food with endangered Australian sea lions (Neophoca cinerea) because both are bottom feeders.
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martin, r. aidan, neil hammerschlag, ralph s. collier, and chris fallows. "predatory behaviour of white sharks (carcharodon carcharias) at seal island, south africa." Journal of the Marine Biological Association of the United Kingdom 85, no. 5 (October 2005): 1121–35. http://dx.doi.org/10.1017/s002531540501218x.
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between 1997 and 2003, there were 2088 natural predations by white sharks (carcharodon carcharias) on cape fur seals (arctocephalus pusillus pusillus) and 121 strikes on towed seal-shaped decoys were documented from observation vessels at seal island, south africa. white sharks at seal island appear to selectively target lone, incoming young of the year cape fur seals at or near the surface. most attacks lasted <1 min and consisted of a single breach, with predatory success rate decreasing rapidly with increasing duration and number of subsequent breaches. a white shark predatory ethogram, composed of four phases and 20 behavioural units, is presented, including four varieties of initial strike and 11 subsequent behaviour units not previously defined in the literature. behaviour units scored from 210 predatory attacks revealed that, for both successful and unsuccessful attacks, polaris breach was the most commonly employed initial strike, while surface lunge was the most frequent second event, closely followed by lateral snap. examination of video footage, still images, and tooth impressions in decoys indicated that white sharks at seal island bite prey obliquely using their anterolateral teeth via a sudden lateral snap of the jaws and not perpendicularly with their anterior teeth, as previously supposed. analysis of white shark upper tooth morphology and spacing suggest the reversed intermediate teeth of white sharks occur at the strongest part of the jaw and produce the largest wound. white shark predatory success at seal island is greatest (55%) within one hour of sunrise and decreases rapidly with increasing ambient light; the sharks cease active predation on seals when success rate drops to ±40%; this is the first evidence of cessation of foraging at unproductive times by any predatory fish. at seal island, white shark predatory success is significantly lower at locations where frequency of predation is highest, suggesting that white sharks may launch suboptimal strikes in areas of greatest intraspecific competition; this is the first evidence of social influence on predation in any elasmobranch. idiosyncratic predatory behaviours and elevated success rates of known individual white sharks at seal island suggest some degree of trial-and-error learning. a hypothetical decision tree is proposed that models predatory behaviour of white sharks attacking cape fur seals at the surface.
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Troy, S. K., R. Mattlin, P. D. Shaughnessy, and P. S. Davie. "Morphology, age and survival of adult male New Zealand fur seals, Arctocephalus forsteri, in South Australia." Wildlife Research 26, no. 1 (1999): 21. http://dx.doi.org/10.1071/wr97103.
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Nineteen adult male New Zealand fur seals, Arctocephalus forsteri, were marked and measured at the start of the breeding seasons in November 1992 and 1993 at Cape Gantheaume, Kangaroo Island in South Australia. The age of each seal was estimated from the number of cementum layers in a post-canine tooth. The males that were attempting to hold territories were 7–15 years old and the heaviest was 160 kg. The mass of males could be predicted accurately from linear measurements and several predictive equations enable estimation of mass in the field. The mean annual survival rate for adult male New Zealand fur seals was 76%, which is higher than that in other fur seal species, perhaps reflecting the expanding nature of the A. forsteri population in Australia.
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VOORBERGEN, ANNE, WILLEM F. DE BOER, and LES G. UNDERHILL. "Natural and human-induced predation on Cape Cormorants at Dyer Island." Bird Conservation International 22, no. 1 (March 2012): 82–93. http://dx.doi.org/10.1017/s0959270912000032.
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SummaryTo develop conservation strategies for vulnerable seabird species that need attention, it is important to know which factors influence their breeding productivity. Predation of eggs and chicks can have large influences on seabird reproduction, especially when human disturbance facilitates predation. On Dyer Island, Kelp GullsLarus dominicanusprey on Cape CormorantPhalacrocorax capensiseggs and chicks, whereas Cape fur sealsArctocephalus pusillus pusillusprey on Cape Cormorant fledglings in the waters surrounding the island. Kelp Gulls were estimated to predate 3.8% of the total number of Cape Cormorant eggs and 2.0% of the chicks on the island. These percentages can be expressed as a loss of 4.8% of Cape Cormorant fledglings, which is low compared to the estimated 24.3% mortality of Cape Cormorant fledglings by Cape fur seal predation. Human disturbance facilitated Kelp Gull egg and chick predation and increased the mobbing of cormorant fledglings by Kelp Gulls. Cormorant egg predation by gulls was more frequently reported in the late afternoon. Seal predation was more abundant at the northern side of the island compared to the southern side, was recorded more frequently in the morning, and increased through the breeding season. The altered abundance and distribution of prey, the availability of suitable breeding habitat and mortality from avian cholera, have also influenced the Cape Cormorant’s population size. Hence, the possibility that Cape Cormorants may be locked in a predator-pit, where seals and gulls prevent the population from increasing in size, needs further attention.
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Mecenero, Silvia, Stephen P. Kirkman, and Jean-Paul Roux. "A refined fish consumption model for lactating Cape fur seals (Arctocephalus pusillus pusillus), based on scat analyses." ICES Journal of Marine Science 63, no. 8 (January 1, 2006): 1551–66. http://dx.doi.org/10.1016/j.icesjms.2006.06.005.
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Abstract A refined fish consumption model for lactating Cape fur seals in Namibia during the eight-month lactation period, which allows for spatio-temporal variation in the diet as determined by scat analyses, has been developed. Previous estimates of prey consumption by Cape fur seals have been based mostly on coarse diet composition models. Sensitivity analyses showed that the energetic requirement and mass of lactating females (bioenergetic variables), as well as the energetic density of prey (diet variable), contributed most to the uncertainty in consumption estimates. Uncertainty in the remaining input variables had minimal effects on the estimates of food consumption. The consumption of commercial prey (horse mackerel, hake and pelagic fish) was greatest by the colony at Cape Cross. The model estimated that a female of average mass 55 kg ingested, on average, 11% of her body mass per day. This model is easily applied to other age/sex classes of the seal population. It permits improvement of the estimates of prey consumption by seals, which are useful for assessing levels of competitive interactions between seals and fisheries or other predators, or the impacts of seals on prey species.
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Penry, Gwenith S., Ashwynn C. Baartman, and Marthán N. Bester. "Vagrant elephant seal predation on Cape fur seal pups, Plettenberg Bay, South Africa." Polar Biology 36, no. 9 (June 8, 2013): 1381–83. http://dx.doi.org/10.1007/s00300-013-1350-4.
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Kirkman, S. P., D. P. Costa, A. L. Harrison, P. G. H. Kotze, W. H. Oosthuizen, M. Weise, J. A. Botha, and J. P. Y. Arnould. "Dive behaviour and foraging effort of female Cape fur seals Arctocephalus pusillus pusillus." Royal Society Open Science 6, no. 10 (October 2019): 191369. http://dx.doi.org/10.1098/rsos.191369.
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While marine top predators can play a critical role in ecosystem structure and dynamics through their effects on prey populations, how the predators function in this role is often not well understood. In the Benguela region of southern Africa, the Cape fur seal ( Arctocephalus pusillus pusillus ) population constitutes the largest marine top predator biomass, but little is known of its foraging ecology other than its diet and some preliminary dive records. Dive information was obtained from 32 adult females instrumented with dive recorders at the Kleinsee colony (29°34.17′ S, 16°59.80′ E) in South Africa during 2006–2008. Most dives were in the depth range of epipelagic prey species (less than 50 m deep) and at night, reflecting the reliance of Cape fur seals on small, vertically migrating, schooling prey. However, most females also performed benthic dives, and benthic diving was prevalent in some individuals. Benthic diving was significantly associated with the frequency with which females exceeded their aerobic dive limit. The greater putative costs of benthic diving highlight the potential detrimental effects to Cape fur seals of well-documented changes in the availability of epipelagic prey species in the Benguela.
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Klein, Richard G., Kathryn Cruz-Uribe, David Halkett, Tim Hart, and John E. Parkington. "Paleoenvironmental and Human Behavioral Implications of the Boegoeberg 1 Late Pleistocene Hyena Den, Northern Cape Province, South Africa." Quaternary Research 52, no. 3 (November 1999): 393–403. http://dx.doi.org/10.1006/qres.1999.2068.
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Boegoeberg 1 (BOG1) is located on the Atlantic coast of South Africa, 850 km north of Cape Town. The site is a shallow rock shelter in the side of a sand-choked gully that was emptied by diamond miners. Abundant coprolites, chewed bones, and partially digested bones implicate hyenas as the bone accumulators. The location of the site, quantity of bones, and composition of the fauna imply it was a brown hyena nursery den. The abundance of Cape fur seal bones shows that the hyenas had ready access to the coast. Radiocarbon dates place the site before 37,000 14C yr ago, while the large average size of the black-backed jackals and the presence of extralimital ungulates imply cool, moist conditions, probably during the early part of the last glaciation (isotope stage 4 or stage 3 before 37,000 14C yr ago) or perhaps during one of the cooler phases (isotope substages 5d or 5b) within the last interglaciation. Comparisons of the BOG1 seal bones to those from regional Middle Stone Age (MSA) and Later Stone Age (LSA) archeological sites suggest (1) that hyena and human seal accumulations can be distinguished by a tendency for vertebrae to be much more common in a hyena accumulation and (2) that hyena and LSA accumulations can be distinguished by a tendency for hyena-accumulated seals to represent a much wider range of individual seal ages. Differences in the way hyenas and people dismember, transport, and consume seal carcasses probably explain the contrast in skeletal part representation, while differences in season of occupation explain the contrast in seal age representation. Like modern brown hyenas, the BOG1 hyenas probably occupied the coast year-round, while the LSA people focused their coastal visits on the August–October interval when nine-to-eleven-month-old seals were abundant. The MSA sample from Klasies River Mouth Cave 1 resembles BOG1 in seal age composition, suggesting that unlike LSA people, MSA people obtained seals more or less throughout the year.
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Rotherham, L. S., M. van der Merwe, M. N. Bester, and W. H. Oosthuizen. "Morphology and distribution of sweat glands in the Cape fur seal, Arctocephalus pusillus pusillus (Carnivora:Otariidae)." Australian Journal of Zoology 53, no. 5 (2005): 295. http://dx.doi.org/10.1071/zo04075.
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The present study examined whether sweat glands are present in the skin of the Cape fur seal, Arctocephalus pusillus pusillus. Sweat glands have an important role in thermoregulation; the presence or absence of sweat glands in the fur-covered and naked skin areas of the Cape fur seal was investigated using standard histological procedures and light and scanning electron microscopy. Sweat glands were present in both fur-covered and naked skin areas. The skin layers in the naked skin areas were thicker than those in the fur-covered areas, presumably to protect them against abrasions in the absence of hair. The density of apocrine sweat glands did not differ among the body regions; however, both apocrine and eccrine sweat glands were larger in naked skin areas than in fur-covered areas. This increased size of the glands suggests a more active role for the glands in the naked skin areas, and a higher heat-loss capability through evaporative cooling in these body regions.
Dissertations / Theses on the topic "Cape fur seal"
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Stewardson, Carolyn Louise. "Biology and conservation of the Cape (South African) fur seal Arctocephalus pusillus pusillus (Pinnipedia:Otariidae) from the Eastern Cape coast of South Africa." Connect to this title online, 2001. http://thesis.anu.edu.au/public/adt-ANU20030124.162757/.
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Thesis (Ph. D.)--Australian National University, 2001.Title from PDF title page (viewed May 8, 2005). Consists of reprints of thirteen published papers, some co-authored with others, plus an introductory chapter, two unpublished manuscripts, and a conclusion. Includes bibliographical references.
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Kirkman, Stephen Patrick. "The Cape fur seal : monitoring and management in the Benguela Current ecosystem." Doctoral thesis, University of Cape Town, 2010. http://hdl.handle.net/11427/11572.
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Includes abstract.Includes bibliographical references.
At the root of this thesis was the Benguela Current Large Marine Ecosystem (BCLME) Programme’s project "Top Predators as Biological Indicators of Ecosystem Change in the BCLME" (LMR/EAF/03/02). The objectives of this project were to assess the utility of top predators as biological indicators of ecosystem change in the Benguela Current Ecosystem, and implement an appropriate, integrated, system-wide monitoring programme based on top predators, to support ecosystem-based management in the Benguela Current Ecosystem.
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Huisamen, Johan. "Recolonisation of the Robberg Peninsula by the Cape Fur Seal Arctocephalus pusillus pusillus and its prey preferences." Thesis, Nelson Mandela Metropolitan University, 2012. http://hdl.handle.net/10948/d1006438.
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The Cape fur seal Arctocephalus pusillus pusillus colony at the Robberg Peninsula, Plettenberg Bay, on the south-east coast of South Africa, was driven to extirpation by indiscriminate harvesting by the late 1800s and seals only began to recolonise this site in the 1990s. This study describes the recolonisation process from 2000 to 2009, exploring within- and between-year variation in the number of seals using the site. Numbers increased over the study period from less than 300 animals to over 3 100. Year and month were important in explaining variability in seal counts, whereas sea condition, time of day and lunar phase had minimal explanatory power. Within-year variation in seal counts decreased during the study period, which may indicate an increasing proportion of resident (as opposed to transient) seals in the colony. However, the colony is currently still in a transition phase with a low ratio of breeding to non-breeding animals and low numbers of pups born on the colony (currently still < 100 per year). The influx of seals to the Robberg area may be associated with an increase in prey availability in the area. The relative protection afforded by the Nature Reserve status of the Robberg Peninsula and the existence of a Marine Protected Area adjacent to it are likely to contribute to the growth of this colony. However, human interference associated with fishing and/or ecotourism on the Peninsula may prevent the colony from developing into a breeding colony. Faecal (scat) sampling was employed to study the diet of this increasing seal population at Robberg. Species composition and size of prey were determined, temporal variation in the diet was explored, and the potential for competition between seals and the fisheries around Plettenberg Bay was investigated. Of the 445 scats collected, 90 % contained hard prey remains. These comprised of 3 127 identified otoliths representing 15 teleost prey species, 25 cephalopod beaks representing three 6 species and three feathers representing two bird species. The seals' most important prey species in terms of numerical abundance and frequency of occurrence in the diet were anchovy, sardine, horse mackerel, sand tongue-fish and shallow-water hake (in decreasing order of importance). The proportion of anchovy in the diet increased during the study period, while sardine decreased. Sardine was the only species that increased significantly in the diet during the upwelling season. Little evidence was found of direct competition between seals and linefisheries in Plettenberg Bay, both in terms of prey species composition and quantities consumed. Scat sampling in seals holds promise as a method to track long-term changes in prey species availability. The conservation and management of this colony are discussed in light of the research findings.
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Stewardson, Carolyn Louise. "Biology and conservation of the Cape (South African) fur seal arctocephalus pusillus pusillus (Pinnipedia: Otariidae)from the Eastern Cape Coast of South Africa /." View thesis entry in Australian Digital Theses Program, 2001. http://thesis.anu.edu.au/public/adt-ANU20030124.162757/index.html.
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Wickens, Patricia Anne. "Interactions of the South African fur seal and fisheries in the Benguela ecosystem." Doctoral thesis, University of Cape Town, 1989. http://hdl.handle.net/11427/22566.
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Bibliography: pages 168-180.This thesis adopts an holistic approach to evaluation of the "seal problem", which encompasses the operational and biological interactions between the South African fur seal and fisheries in the Benguela Ecosystem. The operational interactions are examined using a qualitative assessment, and speculative, single-species simulation models are developed to improve understanding of seal population dynamics, present options for seal management and explore seal-fishery interactions. The models show that the probability of a seal living longer than 20 years is 14%; that the population has increased at a rate of 5.1 % p.a. since the last major census in 1983; that in 1988 there were an estimated 1.5 million seals that consumed over 2 million tons of fish; that although seal population size is usually estimated by multiplying the number of pups by a factor of 4, this factor is very variable and under different culling regimes is usually greater than 4; that historically, the mean population : pup ratio is 4.55. The most effective means of reducing the population is to cull both pups and bulls (the population decrease resulting mainly from reduced pup production caused by disturbance during bull culling). Culling pups is the least effective means of population control. Culling cows alters the population sex ratio drastically and is considered undesirable. To achieve a small or negative population growth rate, more bulls and pups need to be culled than have been taken historically. Each of the fisheries is found to be subject to operational interactions with seals, this being most severe for the purse-seine fishery. The per capita consumption of fish by seals is similar under any management regime so it is not justified to adopt a particular culling strategy to reduce overall consumption. When either seal predation or fishing mortality is reduced, the model simulates an increase in fishery yield of Cape hakes. But there is inadequate understanding of hake population dynamics at present, and depending on the interactions between species, decreased predation may result in increased or decreased fishery yields. This study shows that operational interactions are a real problem and this biases the opinion of fishermen towards seals as competitors for fish resources.
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Mecenero, Silvia. "The diet of the Cape fur seal Arctocephalus pusillus pusillus in Namibia : variability and fishery interactions." Doctoral thesis, University of Cape Town, 2005. http://hdl.handle.net/11427/4387.
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Stewardson, Carolyn Louise, and carolyn stewardson@anu edu au. "Biology and conservation of the Cape (South African) fur seal Arctocephalus pusillus pusillus (Pinnipedia: Otariidae) from the Eastern Cape Coast of South Africa." The Australian National University. Faculty of Science, 2002. http://thesis.anu.edu.au./public/adt-ANU20030124.162757.
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[For the Abstract, please see the PDF files below, namely "front.pdf"] CONTENTS. Chapter 1 Introduction. Chapter 2 Gross and microscopic visceral anatomy of the male Cape fur seal with reference to organ size and growth. Chapter 3 Age determination and growth in the male Cape fur seal: part one, external body. Chapter 4 Age determination and growth in the male Cape fur seal: part two, skull. Chapter 5 Age determination and growth in the male Cape fur seal: part three, baculum. Chapter 6 Suture age as an indicator of physiological age in the male Cape fur seal. Chapter 7 Sexual dimorphism in the adult Cape fur seal: standard body length and skull morphology. Chapter 8 Reproduction in the male Cape fur seal: age at puberty and annual cycle of the testis. Chapter 9 Diet and foraging behaviour of the Cape fur seal. Chapter 10(a) The Impact of the fur seal industry on the distribution and abundance of Cape fur seals. Chapter 10(b) South African Airforce wildlife rescue: Cape fur seal pups washed from Black Rocks, Algoa Bay, during heavy seas, December 1976. Chapter 11(a) Operational interactions between Cape fur seals and fisheries: part one, trawl fishing. Chapter 11(b) Operational interactions between Cape fur seals and fisheries: part two, squid jigging and line fishing. Chapter 11(c) Operational interactions between Cape fur seals and fisheries: part three, entanglement in man-made debris. Chapter 12 Concentrations of heavy metals (Cd, Cu, Pb, Ni & Zn) and organochlorine contaminants (PCBs, DDT, DDE & DDD) in the blubber of Cape fur seals. Chapter 13 Endoparasites of the Cape fur seal. Chapter 14(a) Preliminary investigations of shark predation on Cape fur seals. Chapter 14(b) Aggressive behaviour of an adult male Cape fur seal towards a great white shark Carcharodon carcharias. Chapter 15 Conclusions and future directions.
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De, Vos Alta. "Anti-predator behaviour of Cape fur seals Arctocephalus pusillus pusillus in relation to predation by white sharks Carcharodon carcharias around Seal Island, False Bay, South Africa." Doctoral thesis, University of Cape Town, 2010. http://hdl.handle.net/11427/10423.
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Includes bibliographical references (leaves 161-202).How predators affect the behaviour of their prey is one of the most studied subjects in behavioural ecology, with many hypothesis and models explaining how animals should behave and even more descriptive studies detailing how they do. The unification of the empirical with the theoretical, however, remains limited. The overall aim of my thesis was to address this paucity at Seal Island, South Africa, where recently quantified patterns of predation pressure by white sharks Carcharodon carcharias on Cape fur seals Arctocephalus pusillus pusillus suggested a landscape of fear particularly apposite to this.
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Pillay, Pavitray. "Competition for anchovy (Engraulis capensis) and sardine (Sardinops sagax) between the Cape Gannet (Morus capensis), Cape fur seal (Arctocephalus pusillus pusillus) and the purse-seine fishery on the west coast of South Africa." Master's thesis, University of Cape Town, 2002. http://hdl.handle.net/11427/7422.
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Bibliography : leaves 59-65.Competition for pelagic fish resources was investigated by assessing the overlap in the food base of three land-based predators: Cape gannet (Morus capensis), Cape fur seal (Arctocephalus pusillus pusillus) and humans operating via a purse-seine fishery. Multivariate analysis the diet composition of gannets and seals and the catch composition of the pelagic fishery indicated that there were three ""feeding regimes"" during the 21-year study period: (1978-1998), an anchovy-dominated regime (1978-1983), an intermediate regime (1984-1990) and a sardine-abundant regime (1991-1998). It further showed that anchovy (Engraulis capensis) and sardine (Sardinops sagax) contributed substantially to the catches of all three top predators. Analysis of size-distributions of catches showed that the three predators generally caught the same sizes of anchovy and sardine, reflecting very little resource partitioning. The analysis demonstrated stronger competition between gannets and the purse-seiners than between gannets and seats, especially during seasons of poor recruitment. Furthermore, seasonal differences in the catches of the three predators are related to the recruitment, growth and migration of the prey species. The study confirmed previous observations that gannets prefer sardine to anchovy by showing gannet exploitation of sardine in the early 19905, when anchovy was still abundant. The gannets, which are species-specific feeders, may be impacted by substantial removals of pelagic fish resources by a large seal population and a large fishery.
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Jewell, Oliver Joseph David. "Foraging ecology of white sharks Carcharodon carcharias at Dyer Island, South Africa." Diss., University of Pretoria, 2012. http://hdl.handle.net/2263/30926.
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Dyer Island is thought to host one of the most abundant populations of
white sharks on the planet; this is often credited to the large (55 – 60,000) Cape fur
seal colony at Geyser Rock. Yet relatively little work has ever been produced from
the area. This may be attributed to the harshness in its location as a study site, exposed
to wind and swell from west to east which limits research periods. This study
accounts for over 220 hrs of manual tracking at Dyer Island with a further 68 added
from the inshore shallow areas of the bay. Sharks focused their movements and
habitat use to reefs or channels that allowed access to Cape fur seals. Movement-
Based Kernel Estimates (MKDE) were used to compute home range estimates for
shark movements through and around the heterogeneous structures of Dyer Island and
Geyser Rock. Inshore two core areas were revealed, one being the major reef system
at Joubertsdam and the other at a kelp reef where the tracked shark had fed on a Cape
fur seal. At Dyer Island one core area was identified in a narrow channel, ‘Shark
Alley’, here a second tracked shark foraged for entire days within meters of rafting
Cape fur seals.
Rate of Movement (ROM) and Linearity (LI) of tracks were low during daytime and
movements were focused around areas such as Shark Alley or other areas close to the
seal colony before moving into deeper water or distant reefs with higher rates of ROM
and LI at night. If moonlight was strong foraging would take place to the south of
Geyser Rock but with higher ROM and LI than observed during the day. Foraging
patterns in this study contrast studies from other sites in South Africa and home range
and activity areas were comparatively much smaller than observed in Mossel Bay. It has been established that several known white sharks forage at Dyer Island and the
other studied aggregation sites, such differences in foraging would suggest that they
are able to adapt their foraging behaviour to suit the environment they are in; making
them site specific in their foraging ecology.
Both satellite and acoustic telemetry are revealing aggregation hotspots of white
sharks in South Africa. It is important that such information is used to assist the
recovery of the species which has been protected since 1991, yet is rarely considered
in planning of coastal developments.Dissertation (MSc)--University of Pretoria, 2012.
Zoology and Entomology
MSc
Unrestricted
Books on the topic "Cape fur seal"
1
Shaughnessy, P. D. Population size of the Cape fur seal, Arctocephalus pusillus. Cape Town: Republic of South Africa, Dept. of Environment Affairs, Sea Fisheries Research Institute, 1987.
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Shaughnessy, P. D. Population size of the Cape fur seal, Arctocephalus pusillus. Cape Town: Republic of South Africa, Dept. of Environment Affairs, Sea Fisheries Research Institute, 1993.
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3
M, Bridgeford, and Berry Hu, eds. Cape cross: Past and present. Walvis Bay, Namibia: P. & M. Bridgeford, 2002.
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4
Population size of the Cape fur seal Arctocephalus pusillus. Cape Town: Sea Fisheries Research Institute, 1999.
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Oosthuizen, W. H. Non-breeding colonies of the South African (Cape) fur seal, Arctocephalus pusillus pusillus in southern Africa. Cape Town: Republic of South Africa, Dept. of Environment Affairs, Sea Fisheries Research Institute, 1988.
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Kaufman, Nancy. Easter Seal Eldercare Project: Program guide. Washington, DC (1350 New York Ave., N.W., Suite 915, Washington 20005): National Easter Seal Society, 1995.
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Rutta, Randall L. Easter Seal Eldercare Project: Final report. [Washington, DC] (1350 New York Ave., N.W., Ste. 915, Washington 20005): Easter Seals, 1994.
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Wysocki, Heather M. Four Seas Ice Cream: Sailing through the sweet history of Cape Cod's favorite ice cream parlor. Charleston, SC: History Press, 2012.
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9
1947-, Bowdon Susan Jane, ed. Beyond peek-a-boo and pat-a-cake: Activities for baby's first twenty-four months. 3rd ed. Clinton, NJ: New Win Publishing, 1993.
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1947-, Bowdon Susan Jane, ed. Beyond peek-a-boo and pat-a-cake: Activities for baby's first eighteen months. Piscataway, NJ: New Century Publishers, 1986.
Find full textBook chapters on the topic "Cape fur seal"
1
Riden, Jan, and Allan Bowell. "Deciding on a Product or Service to Sell." In Integrated Case Studies for Foundation Programmes, 156–76. London: Macmillan Education UK, 1991. http://dx.doi.org/10.1007/978-1-349-10546-5_15.
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van Gysen, Herman, and Charles L. Merry. "Towards A Cross-Validated Spherical Spline Geoid for the South-Western Cape, South Africa." In Sea Surface Topography and the Geoid, 53–60. New York, NY: Springer New York, 1990. http://dx.doi.org/10.1007/978-1-4684-7098-7_7.
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Riboud, Jacques. "How to Sell a Currency that is Better Than All the Others." In The Case for a New ECU, 105–17. London: Palgrave Macmillan UK, 1989. http://dx.doi.org/10.1007/978-1-349-09730-2_12.
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ElHalawani, Amina. "Seeking Home." In The Case for Reduction, 213–26. Berlin: ICI Berlin Press, 2022. http://dx.doi.org/10.37050/ci-25_11.
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The question of home is a complicated one. While home is emplaced, the notion of home does not simply point to just a location. This chapter thus utilizes what I call the trope of the ‘vignette’ to look at the concept of home in order to identify some aspects of what constitutes and/or (re)creates it for displaced individuals. It does so by performing a close reading of key moments in the film Salt of this Sea by Annemarie Jacir and the collection of essays The Idea of Home by John Hughes.
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Mees, J., and P. J. H. Reijnders. "The harbour seal, Phoca vitulina, in the Oosterschelde: decline and possibilities for recovery." In The Oosterschelde Estuary (The Netherlands): a Case-Study of a Changing Ecosystem, 547–55. Dordrecht: Springer Netherlands, 1994. http://dx.doi.org/10.1007/978-94-011-1174-4_39.
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Spanier, Benny. "Freedom of Navigation in the Suez Canal and the Channels: Law of the Sea." In Palgrave Studies in Maritime Politics and Security, 117–33. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-15670-0_6.
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AbstractThe chapter examines the status of international canals and straits connecting Two Parts of the High Seas under the Law of the Sea. Strait is a natural phenomenon, while a canal is artificial. At the same time, having a similar role and designation—a passage between seas—one could assume that their legal status, as far as freedom of navigation is concerned, would be the same. Straits have been extensively and comprehensively dealt with over the years by littoral nations, and today there is a complete and innovative chapter on this subject in the 1982 United Nations Convention on the Law of the Sea. However, the Convention is silent on canals. In the first part of the chapter, the terms “strait” and “canal” will be defined with an emphasis on the Suez Canal with regard to the right to freedom of navigation. The second part will describe the development of the right to freedom of navigation in the Suez Canal and the straits. One can see that while with straits there has been, over the years, a process of development with regard to navigation rights in the Law of the Sea, this is not the case with regard to canals subject to specific conventions, and specifically, the Suez Canal. The third part of the chapter will be devoted to a discussion leading to some conclusions on the differences between the two passages, which will assess whether these differences have future significance in the particular context of the Suez Canal.
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Maciel, Carolina, and Bettina Bock. "Animal welfare measures and the WTO Post-EC - seal products case: a renewed debate and research agenda." In The economics of farm animal welfare: theory, evidence and policy, 156–72. Wallingford: CABI, 2020. http://dx.doi.org/10.1079/9781786392312.0156.
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Abstract For nearly 20 years trade officials and scholars debated whether a national measure restricting trade on the basis of animal welfare concerns could be deemed compliant with the rules of the World Trade Organization (WTO). In June 2014, the dispute settlement body of the WTO adopted the decision on the EC - Seal Products case confirming that trade-restrictive measures aimed at safeguarding the welfare of animals can be deemed necessary to protect citizens' moral concerns. While this decision provides long-awaited answers and insights, it does not exhaust the debate on the obstacles for justifying animal welfare trade restrictions. This paper provides an overview of controversies surrounding the topic of animal welfare from a WTO perspective and a brief review of the findings from the EC - Seal Products case. In addition, this chapter calls for further research on potential controversies that may rise in relation to trade measures in contexts beyond seal hunting; like, for instance, regulatory divergences over farm animal welfare measures. In doing so, it recommends that future research pays special attention to the potential controversies associated with the use of animal welfare recommendations elaborated by the World Organisation for Animal Health (OIE) (OIE, 2019).
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North, Michael. "Mari connessi." In Atti delle «Settimane di Studi» e altri Convegni, 5–25. Florence: Firenze University Press, 2019. http://dx.doi.org/10.36253/978-88-6453-857-0.02.
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Following Fernand Braudel’s Méditerranée, historians interpreted the Mediterranean, Baltic, Atlantic, Indian Ocean or Pacific as closed maritime systems, consisting of multiple micro-environments. This essay seeks to overcome these limited perspectives and to examine, how the various seas and oceans were connected by the Vikings, the Cairo Genizah merchants and the Italian trading companies of the Middle Ages. The second part of my article “Connected Seas” examines the perception and memory of the seas as an element of maritime connectivity. It introduces the concept of realm of memory (lieu de mémoire) into maritime history and tests it in four case studies on the Sound, the Straits of Gibraltar, the Dardanelles and the Straits of Malacca.
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Straube, Sirko, Nina Hoyer, Niels Will, and Frank Kirchner. "The Challenge of Autonomy: What We Can Learn from Research on Robots Designed for Harsh Environments." In Robots in Care and Everyday Life, 57–80. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-031-11447-2_4.
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AbstractIn addition to areas of application in people’s everyday lives and the area of education and services, robots are primarily envisioned in non-immediate living environments by the society—i.e., in inaccessible or even hostile environments to humans. The results of this population survey clearly demonstrate that such application options come across with a high level of acceptance and application potential among the population. Nevertheless, it is expected that the underlying AI in such systems works reliably and that safety for humans is guaranteed.In this chapter, the results of the study are compared with state-of-the-art systems from classical application environments for robots, like the deep-sea and space. Here, systems have to interact with their environment to a large extent on their own over longer periods of time. Although typically the designs are such that humans are able to intervene in specific situations and so external decisions are possible, the requirements for autonomy are also extremely high. From this perspective one can easily derive what kind of requirements are also necessary, and what challenges are still in front of us, when robots should be acting largely autonomous in our everyday life.
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Ivanova Boncheva, Antonina, and Alfredo Bermudez-Contreras. "Blue Carbon in Emissions Markets: Challenges and Opportunities for Mexico." In Springer Climate, 265–83. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-82759-5_13.
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AbstractMangroves are ecosystems made up of trees or shrubs that develop in the intertidal zone and provide many vital environmental services for livelihoods in coastal areas. They are a habitat for the reproduction of several marine species. They afford protection from hurricanes, tides, sea-level rise and prevent the erosion of the coasts. Just one hectare of mangrove forest can hold up to 1,000 tons of carbon dioxide, more than tropical forests and jungles. Mexico is one of the countries with the greatest abundance of mangroves in the world, with more than 700,000 ha. Blue carbon can be a novel mechanism for promoting communication and cooperation between the investor, the government, the users, and beneficiaries of the environmental services of these ecosystems, creating public–private-social partnerships through mechanisms such as payment for environmental services, credits, or the voluntary carbon market. This chapter explores the possibilities of incorporating blue carbon in emissions markets. We explore the huge potential of Mexico’s blue carbon to sequester CO2. Then we analyse the new market instrument that allows countries to sell or transfer mitigation results internationally: The Sustainable Development Mechanism (SDM), established in the Paris Agreement. Secondly, we present the progress of the Commission for Environmental Cooperation (CEC) to standardize the methodologies to assess their stock and determine the magnitude of the blue carbon sinks. Thirdly, as an opportunity for Mexico, the collaboration with the California cap-and-trade program is analysed. We conclude that blue carbon is a very important mitigation tool to be included in the compensation schemes on regional and global levels. Additionally, mangrove protection is an excellent example of the mitigation-adaptation-sustainable development relationship, as well as fostering of governance by the inclusion of the coastal communities in decision-making and incomes.
Conference papers on the topic "Cape fur seal"
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Gamal, Ahmed M., Bugra H. Ertas, and John M. Vance. "High-Pressure Pocket Damper Seals: Leakage Rates and Cavity Pressures." In ASME Turbo Expo 2006: Power for Land, Sea, and Air. ASMEDC, 2006. http://dx.doi.org/10.1115/gt2006-90858.
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The turbomachinery component of interest in this paper, the pocket damper seal, has the dual purpose of limiting leakage and providing an additional source of damping at the seal location. The rotordynamic coefficients of these seals (primarily the direct stiffness and damping) are highly dependent on the leakage rates through the seals and the pressures in the seals’ cavities. This paper presents both numerical predictions and experimentally obtained results for the leakage and the cavity pressures of pocket damper seals operating at high pressures. The seals were tested with air, at pressures up to 1000 Psi (6.92 MPa), as the working fluid. Earlier flow-prediction models were modified and used to obtain theoretical reference values for both mass flow-rates and pressures. Leakage and static pressure measurements on straight-through and diverging-clearance configurations of eight-bladed and twelve-bladed seals were used for code validation and for calculation of seal discharge coefficients. Higher than expected leakage rates were measured in the case of the twelve-bladed seal, while the leakage rates for the eight-bladed seals were predicted with reasonable accuracy. Differences in the axial pitch lengths of the cavities and the blade profiles of the seals are used to explain the discrepancy in the case of the twelve-bladed seal. The analysis code used also predicted the static cavity pressures reasonably well. Tests conducted on a six-bladed pocket damper seal to further investigate the effect of blade profile supported the results of the eight-bladed and twelve-bladed seal tests and matched theoretical predictions with satisfactory accuracy.
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Bhate, Nitin, Anthony C. Thermos, Mahmut F. Aksit, Mehmet Demiroglu, and Huseyin Kizil. "Non-Metallic Brush Seals for Gas Turbine Bearings." In ASME Turbo Expo 2004: Power for Land, Sea, and Air. ASMEDC, 2004. http://dx.doi.org/10.1115/gt2004-54296.
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A non-metallic brush seal has been developed as an oil seal for use in turbomachinary. Traditionally labyrinth-type seals with larger clearances have been used in such applications. Labyrinth seals have higher leakage rates and can undergo excessive wear in case of rotor instability. Brush seals reduce leakage by up to an order of magnitude and provide compliance against rotor instabilities. Brush seals are compact and are much less prone to degradations associated with oil sealing. This paper describes the benefits and development of the non-metallic brush seals for oil sealing application.
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Soemarwoto, Bambang I., Johan C. Kok, Koen M. J. de Cock, Arjen B. Kloosterman, Gerrit A. Kool, and Joris F. A. Versluis. "Performance Evaluation of Gas Turbine Labyrinth Seals Using Computational Fluid Dynamics." In ASME Turbo Expo 2007: Power for Land, Sea, and Air. ASMEDC, 2007. http://dx.doi.org/10.1115/gt2007-27905.
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The paper presents an investigation on the characteristics of flow through labyrinth seals. The focus of the paper lies in the application of the Computational Fluid Dynamics (CFD) methodology. The Reynolds-Averaged Navier-Stokes equations are employed as the flow governing equations. Turbulence is incorporated through a variant of the two-equation k-ω turbulence model. Three test cases are considered. The first test case concerns a labyrinth seal configuration with a honeycomb land. The computational results are compared to those obtained from seal test rig measurements. The second test case addresses the same labyrinth seal where the honeycomb land is replaced by a solid smooth land. The third test case addresses the flow through a labyrinth seal with canted knives. The CFD method is considered as an analysis tool complementary to rig-testing and enables investigating the effect of new seal design features. Additionally CFD is seen as a tool to support the correct representation of test-data in semiempirical engineering models for seal design. An industrial perspective is presented towards the exploitation of these modeling capabilities for real-life design of seals.
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Wang, Yi, Colin Young, Guy Snowsill, and Tim Scanlon. "Study of Airflow Features Through Step Seals in the Presence of Dis-Engagement Due to Axial Movement." In ASME Turbo Expo 2004: Power for Land, Sea, and Air. ASMEDC, 2004. http://dx.doi.org/10.1115/gt2004-53056.
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Step seals are a particular design variant of the basic labyrinth seal configuration which is widely used to limit leakage from the space between rotating and stationary components. Seals of this type are employed in aero-engines to prevent oil leakage from bearing chambers and to control the flow of secondary cooling air and it follows that the design of step seals is of great importance in the achievement of optimal aero-engine performance. In this paper, numerical modelling of the flow through stepped seals has been carried out in order to gain an insight into the behaviour of the flow in the presence of dis-engagement. In the context of this work, dis-engagement would be deemed to have occurred when to the axial movement between the rotor and stator results in a clear line of sight through the step seal. The flows through the seals were calculated using the commercial CFD package Fluent and the numerical predictions were validated by comparison with test data previously presented in the literature. The model predictions were initially obtained using a number of alternative two-equation turbulence models and the RNG k-ε turbulence model with the non-equilibrium wall function was found to be in closest agreement with the measured data. It was noted that for a given radial clearance the step seal’s flow characteristic is largely dictated by the fin tip to step distance. It was found that there are two distinct stages of step seal dis-engagement. The first stage of dis-engagement occurs when the seal fin is displaced axially from its nominal position, but the seal fin still remains within the axial extent of the corresponding seal step. In this case the flow through the seal only deviates slightly from that of the fully engaged seal. The second stage occurs when the fin is subjected to a larger axial displacement and as a result assumes a position beyond the corresponding seal step. This results in a much larger seal clearance and the flow through the seal increases significantly with the fin tip to step distance in the case.
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Kang, Y., T. S. Kim, S. Y. Kang, and H. K. Moon. "Aerodynamic Performance of Stepped Labyrinth Seals for Gas Turbine Applications." In ASME Turbo Expo 2010: Power for Land, Sea, and Air. ASMEDC, 2010. http://dx.doi.org/10.1115/gt2010-23256.
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This paper presents the leakage performance of various stepped labyrinth seals. A stationary seal test rig was set up and the leakage characteristics of three seal configurations with different numbers of steps and teeth were investigated for wide operating ranges in terms of pressure ratio and tip clearance. Both the solid and honeycomb land structures were tested. In the honeycomb case, two different sizes were used. The seal was shaped, typical of labyrinth seals for gas turbine applications. The influences of seal configuration, and clearance and honeycomb sizes on the leakage performance were investigated. The relative performances between different seal configurations were compared and their dependence on the land structure was investigated. The honeycomb structure was found to increase leakage for all test conditions. The leakage ratio (honeycomb/solid) was analyzed in terms of geometric variables.
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Ghasripoor, Farshad, Norman A. Turnquist, Mark Kowalczyk, and Bernard Couture. "Wear Prediction of Strip Seals Through Conductance." In ASME Turbo Expo 2004: Power for Land, Sea, and Air. ASMEDC, 2004. http://dx.doi.org/10.1115/gt2004-53297.
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Labyrinth seal assemblies are often used to reduce gas and/or steam leakage in turbines. Caulked-in continuous strip seals are one of the common forms of seals employed on both the rotating and stationary components of turbines. Labyrinth seals perform best when minimum clearances are achieved during the steady state operation of the turbine. However, the design of the turbine and its operation during transient periods of start-up, shut-down and hot re-start often result in interference between the seal components. In the case of the strip seals, this leads primarily to wear of the strip, which in effect adds to leakage. The aim of this paper is to show that strip tip heating and melting during the rub is the main mechanism of wear in the strip. Hence thermal conductivity through the strip and into the body mass in which it is caulked is the primary controlling factor in seal wear. This paper will discuss the use of thermal conductivity and geometry of the strip in predicting wear during high speed rubs against a proprietary material. A close correlation between calculated and experimental strip seal wear data with a number of seal alloys will be demonstrated. Test data will indicate that material properties such as tensile strength and hardness have a minor effect on the wear behavior of continuous seal elements during high-speed rubs.
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Ludlow, C., A. Cutler, and S. Klepper. "Hydrogel Embedded Foam Actuators for Emergency Seal Applications: Improved Safety and Reduced Costs." In SNAME Maritime Convention. SNAME, 2014. http://dx.doi.org/10.5957/smc-2014-p42.
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Bulkhead and hull penetrations have the potential to cause substantial safety concerns during a seal failure (in the case of a stern tube seal) or a flooding event (in the case of a bulkhead seal or bulkhead penetration). In some instances,it is advantageous for these penetrations to have a running clearance during normal operating conditions and then seal during a flooding event. This paper will present the safety and cost benefits of a new seal approach for hull and bulkhead penetrations where a hydrogel embedded foam actuator is utilized. The paper will focus on applications of bulkhead seals, emergency backup stern tube seals and pipe and wire penetrations.
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Alme, Johannes, and Ove Gudmestad. "Past Experience from Arctic Commercial Expeditions." In SNAME 9th International Conference and Exhibition on Performance of Ships and Structures in Ice. SNAME, 2010. http://dx.doi.org/10.5957/icetech-2010-153.
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In the past, Norwegian vessels have entered the Arctic for fishing and for hunting whales and seals. The seal hunters needed to go to the iceedge or into the ice to catch the seals and their activity created much needed income in the past. These seal hunters came mainly from the Aalesund area of Norway (many came from the village of Brandal) and from the Tromsø area in the north. Although seal hunting is controversial to day, there might be important learning to bring to new industries like the offshore oil and gas industry and to the navigators in ice infested northern waters. An activity within the research project “PetroArctic” at NTNU has focused on collecting experience data from the seal hunters, (Alme, 2009). A number of interviews with elders (age from 70 to 80+) have been conducted with focus on the physical environmental conditions, vessel behavior in ice and causes of loss of vessels. Among those interviewed were the legendary captain Paul Stark who sailed on sealers from 1950 to 2000 and who was involved in three vessel losses. Newspaper records from the early decades of the 20th century have been reviewed. Prior to the time of steel hull ships with diesel engines, wooden ships with sails and thereafter with steam engines were used. There were frequent losses caused by ice pressure and vessel implosions. Losses were also due to interaction with “ice foots” (Figure1) of multiyear ridges or due to hits from floating ridges on waves. The paper presents characteristic features of vessels used and ice conditions for the different areas where seal hunting took place. These were the Newfoundland area, Labrador coast, Danish Strait, the Area in vicinity of Jan Mayen, North East Greenland coast, Spitzbergen, Eastern Barents Sea towards Novaya Zemlya and the mouth of the White Sea (Figure 2). The causes for the losses or damages to vessels are reviewed in details. In this respect it should be noted that although the ice cap might be shrinking in the future, there will be ice parts of the year over large areas. The ice might even move faster than in the past and get to new areas that traditionally have been ice free. This also relate to the ice of the polar pack that might move more than in the past. There is therefore a strong encouragement to implement the learning of the Arctic pioneers.
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Kosowski, Krzysztof, and Robert Ste˛pien´. "Reduction of Pressure Forces in Turbine Labyrinth Seals." In ASME Turbo Expo 2010: Power for Land, Sea, and Air. ASMEDC, 2010. http://dx.doi.org/10.1115/gt2010-22391.
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The paper describes a chamber seal reducing the aerodynamic forces created in shroud seals. This kind of turbine seal was patented and tested. The investigations into the pressure field in the shroud gap were performed by means of CFD Fluent Code and compared with the results measured on a single-stage air model turbine of the impulse type. Special attention was paid to the pressure field in the rotor blade shroud clearance in the situation when rotor-stator eccentricity led to asymmetrical flows in blade passages and shroud gaps. The investigations were carried out for different types of shrouds, various shapes and dimensions of the chambers, and for different turbine working conditions. The calculations were verified by the experimental research. The performed investigations proved that the chamber seal could remarkably reduce aerodynamic forces generated in turbine clearances due to rotor-stator eccentricity. The results proved that: - the proposed chamber seal can reduce pressure forces acting on the blade shroud by about 30%–60%, depending on the type of the shroud; - the chamber seals are specially effective in the case of relatively small radial clearances; - the proposed method may be applied in active control of aerodynamic forces generated in turbine shroud seals; - the presented seal modification can be easily introduced to turbines in operation and to the newly-designed ones. It must be emphasized that according to the calculations and experiments the application of the chamber to typical labyrinth shroud seals does not affect the flows in the turbine blade channels.
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Duran, E. Tolga, Mahmut F. Aksit, and Murat Ozmusul. "CAE Based Brush Seal Characterization for Stiffness and Stress Levels." In ASME Turbo Expo 2015: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/gt2015-44068.
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Brush seals are complex structures having variety of design parameters, all of which affect the seal behavior under turbine operating conditions. The complicated nature of the seal pack and frictional interactions of rotor, backing plate and bristles result in nonlinear response of the brush seal to variances of design parameters. This study presents CAE based characterization of brush seals, which aims to investigate the main effects of several brush seal design parameters on brush seal stiffness and stress levels. Characterization work of this study includes free-state rotor rub (unpressurized seal), steady state (pressure load without rotor interference) and pressurized-rotor interference conditions.
Reports on the topic "Cape fur seal"
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Bryan Sallee, Colleen E., and Jared M. Ragland. Dolphins in human care sampling protocol and Sample Entry Assistant (SEA) for tissue archival and analyte analysis. Gaithersburg, MD: National Institute of Standards and Technology, January 2020. http://dx.doi.org/10.6028/nist.ir.8281.
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Boyle, Maxwell, and Elizabeth Rico. Terrestrial vegetation monitoring at Cape Hatteras National Seashore: 2019 data summary. National Park Service, January 2022. http://dx.doi.org/10.36967/nrr-2290019.
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The Southeast Coast Network (SECN) conducts long-term terrestrial vegetation monitoring as part of the nationwide Inventory and Monitoring Program of the National Park Service (NPS). The vegetation community vital sign is one of the primary-tier resources identified by SECN park managers, and monitoring is currently conducted at 15 network parks (DeVivo et al. 2008). Monitoring plants and their associated communities over time allows for targeted understanding of ecosystems within the SECN geography, which provides managers information about the degree of change within their parks’ natural vegetation. The first year of conducting this monitoring effort at four SECN parks, including 52 plots on Cape Hatteras National Seashore (CAHA), was 2019. Twelve vegetation plots were established at Cape Hatteras NS in July and August. Data collected in each plot included species richness across multiple spatial scales, species-specific cover and constancy, species-specific woody stem seedling/sapling counts and adult tree (greater than 10 centimeters [3.9 inches {in}]) diameter at breast height (DBH), overall tree health, landform, soil, observed disturbance, and woody biomass (i.e., fuel load) estimates. This report summarizes the baseline (year 1) terrestrial vegetation data collected at Cape Hatteras National Seashore in 2019. Data were stratified across four dominant broadly defined habitats within the park (Maritime Tidal Wetlands, Maritime Nontidal Wetlands, Maritime Open Uplands, and Maritime Upland Forests and Shrublands) and four land parcels (Bodie Island, Buxton, Hatteras Island, and Ocracoke Island). Noteworthy findings include: A total of 265 vascular plant taxa (species or lower) were observed across 52 vegetation plots, including 13 species not previously documented within the park. The most frequently encountered species in each broadly defined habitat included: Maritime Tidal Wetlands: saltmeadow cordgrass Spartina patens), swallow-wort (Pattalias palustre), and marsh fimbry (Fimbristylis castanea) Maritime Nontidal Wetlands: common wax-myrtle (Morella cerifera), saltmeadow cordgrass, eastern poison ivy (Toxicodendron radicans var. radicans), and saw greenbriar (Smilax bona-nox) Maritime Open Uplands: sea oats (Uniola paniculata), dune camphorweed (Heterotheca subaxillaris), and seabeach evening-primrose (Oenothera humifusa) Maritime Upland Forests and Shrublands: : loblolly pine (Pinus taeda), southern/eastern red cedar (Juniperus silicicola + virginiana), common wax-myrtle, and live oak (Quercus virginiana). Five invasive species identified as either a Severe Threat (Rank 1) or Significant Threat (Rank 2) to native plants by the North Carolina Native Plant Society (Buchanan 2010) were found during this monitoring effort. These species (and their overall frequency of occurrence within all plots) included: alligatorweed (Alternanthera philoxeroides; 2%), Japanese honeysuckle (Lonicera japonica; 10%), Japanese stilt-grass (Microstegium vimineum; 2%), European common reed (Phragmites australis; 8%), and common chickweed (Stellaria media; 2%). Eighteen rare species tracked by the North Carolina Natural Heritage Program (Robinson 2018) were found during this monitoring effort, including two species—cypress panicgrass (Dichanthelium caerulescens) and Gulf Coast spikerush (Eleocharis cellulosa)—listed as State Endangered by the Plant Conservation Program of the North Carolina Department of Agriculture and Consumer Services (NCPCP 2010). Southern/eastern red cedar was a dominant species within the tree stratum of both Maritime Nontidal Wetland and Maritime Upland Forest and Shrubland habitat types. Other dominant tree species within CAHA forests included loblolly pine, live oak, and Darlington oak (Quercus hemisphaerica). One hundred percent of the live swamp bay (Persea palustris) trees measured in these plots were experiencing declining vigor and observed with symptoms like those caused by laurel wilt......less
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Lane, Lerose, R. Gary Hicks, DingXin Cheng, and Erik Updyke. Manual for Thin Asphalt Overlays. Mineta Transportation Institute, October 2020. http://dx.doi.org/10.31979/mti.2020.1906.
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This manual presents best practices on project selection, mix design, and construction to ensure a superior product when constructing thin asphalt overlays. Experience shows these treatments provide excellent performance when placed on pavements in fair to good condition using proper construction techniques. Though sometime referred to by other names, thin asphalt overlays have been widely used for pavement preservation throughout the world for over 50 years. Limited infrastructure funding at the local, state, and federal levels has resulted in greater emphasis on the use of pavement preservation techniques to extend pavement life and reduce maintenance costs. Thin asphalt overlays are one of many preventative maintenance treatments. Thin asphalt overlays are placed directly on existing pavement and can range from 1/2 inch to 1 1/2 inches in thickness. Thin asphalt overlays have proven to be an economical means for maintaining and improving the functional condition of an existing pavement since the 1960s. Specifically, this manual provides guidance for engineers regarding where and when to use thin asphalt overlays including: (1) Types and variations of thin overlays; (2) Materials and the design process; (3) Construction; (4) Quality Assurance; and (5) Troubleshooting. This chapter by chapter guidance enables an Agency’s engineers to design and construct a successful thin asphalt overlay project to completion. This manual is one of four new manuals prepared by the California Pavement Preservation Center (CP2Center) using funding from California Senate Bill 1 (SB-1), passed in April 2017. The other three manuals provide detailed design and construction information for (1) chip seals, (2) slurry surfacing, and (3) Cape seals. The creation of these manuals was a task funded entirely from SB-1 monies for the purpose of disseminating training and technical information on highway pavement preservation to local agencies throughout California.
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Douglas, K., J. V. Barrie, T. Dill, T. Fralic, and N. Koshure. 2021004PGC cruise report: mapping Salish Sea marine geohazards, British Columbia. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/329621.
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The Geological Survey of Canada (GSC) undertook marine fieldwork onboard the Canadian Coast Guard Ship (CCGS) Vector to locate and map potential geohazards and geological features in the Salish Sea in the interest of public safety from August 11-18, 2021. This work was conducted under the Natural Resources Canada Marine Geoscience for Marine Spatial Planning (MGMSP) and the Public Safety Geoscience Programs. The GSC had observed multiple potential faults in existing data near Central Haro Strait, Stuart Channel, South of Hornby Island and near Cape Lazo through existing CHIRP and multibeam bathymetry data but required further data to quantify their activity and potential seismic risk (Barrie et al, 2021). In addition to fault activity, the GSC had detected numerous large underwater landslide deposits in Howe Sound and Saanich Inlet. The GSC required further data to constrain volumes and timing of slide activity. In English Bay the origin and evolution of a field of pockmarks was poorly understood. In Burrard Inlet, the survey required a better understanding of frequency of landslides as well as depth of sediment in order to understand natural sediment depositional rates. The research expedition included deep-tow system (DTS) sub-bottom surveys and multibeam water column and bathymetric surveys in each of these areas to better understand these marine geohazards and processes. Hydrographic surveys were completed by the Canadian Hydrographic Service (CHS) at night in Pylades Channel and near Point Grey to maximize use of ship time. Weather was good, seas were calm, and good quality data were collected. The data collected will be made publicly available and have the potential to contribute to building codes and to help communities in their decision-making and understanding of risks.
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Beck, Tanya, and Ping Wang. Morphodynamics of barrier-inlet systems in the context of regional sediment management, with case studies from West-Central Florida, USA. Engineer Research and Development Center (U.S.), September 2021. http://dx.doi.org/10.21079/11681/41984.
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The temporal and spatial scales controlling the morphodynamics of barrier-inlet systems are critical components of regional sediment management practice. This paper discusses regional sediment management methods employed at multiple barrier-inlet systems, with case studies from West-Central Florida. A decision-support tool is proposed for regional sediment management with discussion of its application to barrier-inlet systems. Connecting multiple barrier islands and inlets at appropriate spatio-temporal scales is critical in developing an appropriately scoped sediment management plan for a barrier-inlet system. Evaluating sediment bypassing capacity and overall inlet morphodynamics can better inform regional sand sharing along barrier-inlet coastlines; particularly where sediment resources are scarce and a close coupling between inlet dredging and beach placement is vital to long-term sustainable management. Continued sea-level rise and anthropogenic activities may intensify the need for investigating longer-term processes and expanding regional planning at a centennial timescale and are acknowledged as challenging tasks for RSM studies. Specifically, we suggested that a regionally focused, multi-inlet study was necessary for management plan of individual inlet for the west-central Florida case studies. Key recommendations based on the case studies are included.
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Thompson, Marshall, and Ramez Hajj. Flexible Pavement Recycling Techniques: A Summary of Activities. Illinois Center for Transportation, July 2021. http://dx.doi.org/10.36501/0197-9191/21-022.
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Cold in-place recycling (CIR) involves the recycling of the asphalt portions (including hot-mix asphalt and chip, slurry, and cape seals, as well as others) of a flexible or composite pavement with asphalt emulsion or foamed asphalt as the binding agent. Full-depth reclamation (FDR) includes the recycling of the entire depth of the pavement and, in some cases, a portion of the subgrade with asphalt, cement, or lime products as binding agents. Both processes are extensively utilized in Illinois. This project reviewed CIR and FDR projects identified by the Illinois Department of Transportation (IDOT) from the Transportation Bulletin and provided comments on pavement designs and special provisions. The researchers evaluated the performance of existing CIR/FDR projects through pavement condition surveys and analysis of falling weight deflectometer data collected by IDOT. They also reviewed CIR/FDR literature and updated/modified (as appropriate) previously provided inputs concerning mix design, testing procedures, thickness design, construction, and performance as well as cold central plant recycling (CCPR) literature related to design and construction. The team monitored the performance of test sections at the National Center for Asphalt Technology and Virginia Department of Transportation. The researchers assisted IDOT in the development of a CCPR special provision as well as responded to IDOT inquiries and questions concerning issues related to CIR, FDR, and CCPR. They attended meetings of IDOT’s FDR with the Cement Working Group and provided input in the development of a special provision for FDR with cement. The project’s activities confirmed that CIR, FDR, and CCPR techniques are successfully utilized in Illinois. Recommendations for improving the above-discussed techniques are provided.
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Hernandez-Abrams, Darixa, Carra Carrillo, and Todd Swannack. Scenario analyses in ecological modeling and ecosystem management. Engineer Research and Development Center (U.S.), July 2022. http://dx.doi.org/10.21079/11681/44840.
Full textAbstract:
Ecosystem management and restoration practitioners are challenged with complex problems, diverse project goals, multiple management alternatives, and potential future scenarios that change the systems of interest. Scenario analysis aids in forecasting, evaluating, and communicating outcomes of potential management actions under different plausible conditions, such as land-use change or sea level rise. However, little guidance exists for practitioners on the utility and execution of scenario analysis. Therefore, this technical note highlights the usefulness of scenario analysis as a tool for addressing uncertainty in potential project outcomes. The mechanics of the scenario-analysis process are explained, and examples of different types of scenario analyses are described for context on the breadth of its use. Lastly, two hypothetical case studies of scenario analysis in ecological modeling are presented showing a semiquantitative approach for assessing anadromous fish and a quantitative approach examining freshwater mussel habitat. Overall, this technical note provides a brief review of the utility and application of scenario analyses in the context of ecological modeling and ecosystem management decision-making.
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Hunter, Janine. Street Life in the City on the Edge: Street youth recount their daily lives in Bukavu, DRC. StreetInvest, 2022. http://dx.doi.org/10.20933/100001257.
Full textAbstract:
Bukavu, a city on the shores of Lake Kivu on the eastern edge of the Democratic Republic of the Congo (DRC), is home to over one million people, many displaced by poverty and the consequences of armed conflicts that continue to affect the east of the country. More than 10,000 street children and youth live here in street situations. 19 street youth helped to create this story map by recording all the visual data and sharing their stories about their daily lives. The story map includes 9 sections and 2 galleries showing street children and youth’s daily lives in Bukavu and the work of Growing up on the Streets civil society partner PEDER to help them. Chapters include details of how street children and youth collect plastics from the shores of Lake Kivu to sell, they cook, and share food together, or buy from restaurants or stalls. Young women earn their living in sex work and care for their children and young men relax, bond and hope to make extra money by gambling and betting. The original language recorded in the videos is Swahili, this has been translated into English and French for the two versions of the map.
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Panko, Mary. Undergraduate Research: A Source for Faculty Publications? Unitec ePress, April 2014. http://dx.doi.org/10.34074/ocds.002.
Full textAbstract:
Over the last two decades undergraduate students have been encouraged to problem solve in ‘the real world’ in order to construct their own subject knowledge. This generally means that students are required to carry out research in their disciplines, a process which inevitably leads to the production of quantities of data. Once their findings are reported back to faculty and have been graded, they are largely ignored, as they are ‘only’ the product of undergraduate research. However, since 2000 there has been a move to bring this type of work into the open through undergraduate research conferences in order to benefit both the students and their institutions. Nevertheless, except for a few publications within medical teaching, faculty themselves have not widely used this data for their own research, perhaps fearing its potential lack of authenticity or credibility. This paper explores a case study to examine the validity and reliability of students’ findings and considers whether the observations obtained by students can or should be made into academic publications by staff. This study comprised four cohorts, totaling 109 second-year undergraduate automotive students, who had made repeat visits to a number of automotive workshops and reviewed the workshops’ activities with a particular focus on customer service, health and safety, and waste management. Analysis of the top 25% of students’ reports revealed that a number of compliance failures were appearing on such a regular basis that these findings should be brought to the attention of the automotive industry. The paper concludes with a recommendation that under carefully controlled conditions, academics should draw on this hitherto ignored seam of research data.
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Panko, Mary. Undergraduate Research: A Source for Faculty Publications? Unitec ePress, April 2014. http://dx.doi.org/10.34074/ocds.002.
Full textAbstract:
Over the last two decades undergraduate students have been encouraged to problem solve in ‘the real world’ in order to construct their own subject knowledge. This generally means that students are required to carry out research in their disciplines, a process which inevitably leads to the production of quantities of data. Once their findings are reported back to faculty and have been graded, they are largely ignored, as they are ‘only’ the product of undergraduate research. However, since 2000 there has been a move to bring this type of work into the open through undergraduate research conferences in order to benefit both the students and their institutions. Nevertheless, except for a few publications within medical teaching, faculty themselves have not widely used this data for their own research, perhaps fearing its potential lack of authenticity or credibility. This paper explores a case study to examine the validity and reliability of students’ findings and considers whether the observations obtained by students can or should be made into academic publications by staff. This study comprised four cohorts, totaling 109 second-year undergraduate automotive students, who had made repeat visits to a number of automotive workshops and reviewed the workshops’ activities with a particular focus on customer service, health and safety, and waste management. Analysis of the top 25% of students’ reports revealed that a number of compliance failures were appearing on such a regular basis that these findings should be brought to the attention of the automotive industry. The paper concludes with a recommendation that under carefully controlled conditions, academics should draw on this hitherto ignored seam of research data.