The aim of this study was to identify the algal genera found in the different freshwater bodies on Marion Island, to relate the presence or absence of the genera to the chemistry of the water bodies and to group the genera according to their limno-chemical preferences. The Island's freshwater algal genera were also compared with genera found on other Southern Ocean islands. The major factors influencing the chemical composition of the freshwaters of the island are the surrounding ocean and the manuring of seals and seabirds. The Western and Southern lakelets and wallows had higher mean conductivity values than most of the other water bodies. Eastern Inland lakelets, crater lakes and glacial lakes had low ion and nutrient concentrations, since they are mainly situated inland, away from bird or seal colonies. The chemical composition of wallows was influenced by manuring of seals and seabirds. The freshwaters are acidic and lakelets tend to be more acidic than glacial lakes. The lentic waters were more acidic than the stream. In total, 106 genera, mainly belonging to Chlorophyta (60 genera; 56% of total) and Cyanophyta (29 genera; 27% of total), were found in the freshwaters on the island. Other algal divisions found were Chrysophyta (7 genera), Euglenophyta (4 genera), Pyrrophyta (2 genera) and Xanthophyta (4 genera). Mean number of genera per sample ranged from 8 (in wallows) to 16 (in Eastern Inland lakelets). Filamentous algae were present in all the samples. Abundant green algae were Cosmarium, Klebsormidium, Mougeotia and Oedogonium. The most common cyanobacteria were Lyngbya and Chroococcus. The filamentous yellow-green alga, Tribonema, was also common. There were distinct differences in the algal composition between the southern, western and northern lakelets and the lakelets on the eastern side of the island. Sixty percent of the algal

French and Smith (1985) used climatic, edaphic and vegetation information in an ordinal comparison to define the position of sub-Antarctic islands in the "tundra spectrum".They showed that sub-Antarctic islands possess almost the full range of vegetation types found in Northern Hemisphere tundra.A particularly significant finding concerned how altitude influenced the islands' climatic and edaphic regimes and their vegetation: "The overall position of the sub-Antarctic islands in the tundra spectrum can be expressed by the altitudinal change needed to go from the lowest altitude "tundra vegetation", usually meadow or mire, to fellfield (or equivalent)-i.e. the increase in altitude required for the elimination of all other vegetation types.In the Northern Hemisphere sites, this is 1-2 m in the high Arctic, 2-20 m in low-Arctic and more severe Sub-arctic sites, 20-200 m in the milder Sub-arctic/Sub-alpine areas, and up to 1,000 m or more in cool-temperate and temperate alpine zones.In the southern islands, the equivalent vegetation change takes 5-50 m, while a further change of 50-500 m eliminates all plants, except scattered short grasses and cushion-forming forbs, and cryptogams" (French and Smith 1985).

On the basis of their vegetation and soils, sub-Antarctic island ecosystems are considered ro be part of the tundra biome.However, sub Antarctic island vegetation is more productive and nutrient cycling more rapid than in Northern Hemisphere tundra.Human occupation and exploitation on the islands has comprised mainly sealing, whaling and, in some instances, fi shing and agriculture.Research stadons have also been established for meteorological monitoring and scientifi c research.All these activities have affected the islands' fl oras and faunas but the greatest impact of humans has been through the introduction of alien organisms.Because the islands' indigenous biotas are species-poor and lack cardinal trophic groups that are common in other ecosystems (especially mammalian herbivores and predators), an introduced species that becomes invasive on an island can have insidious, but far-reaching, effects on ecosystem functioning.Such effects are the focus of this paper and the principal examples given are the effects of the introduced house mouse and a European slug on nutrient cycling at Marion Island.Manuring by seabirds and seals is also an imponant determinant of ecosystem structure and funcdon at sub-Antarctic islands.Introduced domestic cats have reduced burrowing bird populations on some of the islands, and at Marion Island the populations of most surface-nesting birds have also declined, probably due to human exploitation of their oceanic food resources.This has far-reaching implications for ecosystem functioning.The sub-Antarctic region is also becoming warmer; at some islands this is coupled with decreased, and at others with increased, precipitation.Some implications of these climatic changes for ecological functioning are presented.The most important is that a warming climate will increase the probability of introduced organisms becoming established on an island.This, together with increasing human visitation and occupancy (the major cause of species introductions), implies that it is inevitable that the rate of establishment of invasive biota on the sub-Antarctic islands will increase.

Purpose: Caring for bone marrow transplant (BMT) patients in an outpatient clinical setting is very challenging. The patients are usually very sick with multiple complaints that require frequent and timely interventions. Over the years the treatment of BMT patients has changed. One major change, the Autologous Peripheral Blood Progenitor Cell Transplant, has gone from being a hospital procedure, to a common outpatient clinic procedure. This has created a need to extend the Ambulatory Clinic hours to accommodate the growing patient population. Method/outcome summary and conclusions: For the past year, the numbers of calls to the emergency center from the after hours clinics began to increase steadily. The advanced practice nurses who were working extra hours to cover in the emergency center began to keep a record of the calls and the types of problems and interventions required. After a 3-month pilot period, the results were evaluated. The medical needs were classified as urgent, emergent, or routine. The most frequent calls for the total patient population were for nausea and vomiting, fever, blood transfusion and chemotherapy reactions, and pain medication. The most frequent calls for BMT patients were similar. A position was created for a Nurse Practitioner who would see and evaluate the patients in the after hours clinic, freeing the emergency physician to see the patients in the emergency center. Guideline and protocols were developed to guide their practice. The nurse practitioner works closely with the emergency room physician and the primary care doctor. Patients requiring care that is outside the scope of practice of the NP are stabilized and transferred to the emergency center for further treatment. The emergency center physician was usually very busy and not able to come up and see the patient immediately. Implications for Nurse Practitioners: Nurse Practitioners are a valuable asset to the healthcare system. We are constantly developing ways to provide high-quality care to our patients. Since the utilization of Nurse Practitioners in our after hours oncology clinics is a success, we recommend that Nurse Practitioners would be instrumental in other after hours clinic settings.

Feral house mice on sub-Antarctic Marion Island become reproductively active (males scrotal, females with perforate vaginas or pregnant) at an age >60 days and breed until death, which may occur at more than 13 months. Breeding is strongly seasonal; pregnant or lactating females were found only from October to May. A substantial proportion of mice old enough to breed in one summer overwinters to form a significant component of the breeding population the following summer but it is unlikely that any survive a second winter. The onset of breeding is closely synchronized with increasing day length but occurs about 2 months before mean temperature at the ground surface starts to increase significantly. Cessation of breeding is more closely associated with declining temperatures in late summer. For both males and females, the best correlation between reproductive activity and any of the temperature parameters measured was with average maximum temperature 1 cm above the ground. Competition for macroinvertebrate prey increases sharply in early winter due to high mouse numbers. The breeding season in 1991/1992 and 1992/1993 was at least 2 months longer than in 1979/1980, because the mice started breeding earlier, and stopped breeding later, in 1991/1993. The later cessation of breeding in 1991/1993 was despite the fact that there was a greater competition for macroinvertebrate prey, and that mean air temperatures during the early winter months were lower, than in 1979/1980.

We assessed the impact of human trampling in three different habitats on Marion Island (46degrees50'S, 37degrees50'E). The habitats were (1) mires with wet, peaty soils and grass- and bryophyte-dominated vegetation; (2) slopes with relatively dry mineral soils, dominated by small ferns and dwarf shrub; and (3) feldmark on dry mineral soils with an open vegetation of cushion dicots and bryophytes. We Track width (25 to 800 cm) increased with soil moisture content. Trampling reduced vegetation height, total cover, and species richness in mires and feldmark and vegetation height and herb layer cover (but not bryophyte cover or species richness) in slopes. In mires, most species were negatively affected by trampling, but in slopes trampling increased the cover of 6 out of 9 significantly affected species. The total number of species in all trampled plots in mire and feldmark communities was similar to10% lower, but in slopes 28% higher, than in control plots. The impact of trampling differed between growth forms. Cushion dicot, shrub, and fern covers were reduced, whereas graminoid and pleurocarpous moss covers were unaffected or increased with trampling. Trampling reduced the cover of most bryophyte species, but it did increase the cover of some. In the slope habitat, destruction by trampling of the closed herb canopy allows increased light penetration and makes the habitat more favorable for small plants such as bryophytes. We attribute the differences in how the vegetation of different habitats responds to trampling to differences in the structure of the original vegetation as well as differences in soil characteristics, especially the soil's structural stability under pressure. examined existing walking tracks on the island.

An analysis of the stomach contents of house mice (Mus musculus L.) at three sites on Marion Island (47°S, 38°E) over a 1-year period showed that the mice feed mostly on terrestrial macroinvertebrates but that plants (mainly seed) are an important component of the diet in mid- to late summer. Larvae of a flightless moth, weevil larvae and adults and, at one of the sites, earthworms were the invertebrate items that showed the highest importance value over the year. Diet diversity was slightly lower in summer and autumn than in winter and spring. Diet variety was lowest in midsummer and highest in either autumn or winter, depending on the site. Mean stomach-content mass was significantly higher in midwinter than during the rest of the year. When offered prey of different types and sizes, mice selected moth larvae first in 92% of the trials; earthworms or weevil adults were most frequently selected second, and weevil larvae fourth. An introduced slug species was selected only once, as the last choice and only part of it was eaten. With both moth larvae and earthworms, the heaviest individual offered was almost always chosen first. Surprisingly, mice never consumed more than about half of the seed offered to them and their condition deteriorated severely during the trials with seed; in a third of the trials with two types of seed, the mice completely ignored the seed. The impact of mice predation on invertebrates was assessed at two of the sites – a dry mire and a coastal biotic herbfield that is influenced by seabird and seal manuring. Moth larvae and adults, weevil larvae and adults, earthworms, spiders and flies made up >90% of the animal remains in the stomach contents over the year and, on average, the mice daily consumed 45 g (dry mass) ha–1 of those invertebrates at the mire and 194 g ha–1 at the biotic site. Moth larvae made up a substantial proportion of these amounts; average daily consumption was 30 g ha–1 at the mire and 107 g ha–1 at the biotic site. In terms of the amount consumed in relation to biomass, the heaviest impact of mice at both sites was on weevil adults; at the biotic site mice daily consumed 13% of weevil adult biomass in autumn and nearly 6 times the annual average biomass over the year. At the mire, slightly more than the annual average weevil adult biomass was consumed over the year. The consumption of invertebrates by mice found in this study (1992/1993) was about 20% greater than in 1979/1980. The most striking changes in annual average consumption rate between 1979/1980 and 1992/1993 were for weevil larvae (increased nearly fourfold) and earthworms (increased sixfold at the biotic site and threefold at the mire). In contrast, the consumption of spiders at both sites decreased between 1979/1980 and 1992/1993.

Journal Article Terrestrial slug recorded from sub-Antarctic Marion Island Get access V.R. Smith V.R. Smith Department of Botany and Genetics, University of the Orange Free StateBloemfontein, 9301, South Africa Search for other works by this author on: Oxford Academic Google Scholar Journal of Molluscan Studies, Volume 58, Issue 1, February 1992, Pages 80–81, https://doi.org/10.1093/mollus/58.1.80 Published: 01 February 1992

A phenol‐hypochlorite (Berthelot) procedure for determining NH4‐N in acid digests of plant tissue is described. EDTA suppresses Cu interference and precipitation of hydroxides and phosphates. The oxidizing reagent includes an alkaline buffer to account for variations in acidity between digestion solutions, the main source of error in an unbuffered procedure. The reagent combinations and addition sequence employed allow for delays of up to at least 30 minutes between reagent additions without affecting the final colour intensity. The proposed procedure is as sensitive as similar methods used for determining NH4‐N in natural waters and yields results which agree well with those obtained by steam distillation.

Ca, Mg, Na, K and P contents of 3 plant tissues obtained by H2SO4‐H2O2‐Li2SO4‐Se peroxidation digestion were compared with those determined by mixed acid (HNO3‐H2S04‐HC104) and dry ashing procedures. Differences between methods were not consistent between elements or tissue types but the mixed acid digestion generally yielded higher Ca, Mg and P values than did dry ashing and peroxidation. Tissue K contents estimated by both wet digestion techniques were not significantly (P ≤0.05) different. Differences in Na values between digestion methods were highly inconsistent between tissue types and the precision of the Ma data was poor. N contents determined by peroxidation digestion and a conventional Kjeldahl method agreed closely.