Fish community of a small, temperate, urban river in South Africa

Freshwater and marine-spawned fishes were sampled from the Baakens River, a small urban river that runs through the city of Port Elizabeth in the Eastern Cape of South Africa. Using fyke nets, 8 sites were sampled along the river course over a 4-month period (January – April 2014). Catches were comprised of indigenous freshwater, marine migrant and alien fishes. Marine migrant fishes, including catadromous species dependent on freshwater for early life-history strategies, were significantly affected by instream barriers which prohibited upstream migration of all species except Anguilla mossambica. The freshwater fish fauna was dominated by Tilapia sparrmanii and Pseudocrenilabrus philander, species that are alien to the Baakens River. While indigenous Barbus pallidus and Sandelia capensis were both abundant and widely distributed in the river, only two Pseudobarbus afer were sampled from one survey site. The low abundance and narrow distribution of this endangered species is of concern and human-mediated impacts on this species require urgent evaluation and mitigation.Keywords: Baakens River, migration barrier, weir, alien fish, endangered fis

The effects of instream barriers on the distribution of migratory marine-spawned fishes in the lower reaches of the Sundays River, South Africa

The distribution and abundance of migratory marine-spawned fish species was investigated in the lower reaches of the warm temperate Sundays River, Eastern Cape, South Africa. Fish were collected above and below manmade instream barriers using multi-meshed gill net fleets, 12 mm mesh fyke nets and 1 mm mesh fyke nets. Sampling was undertaken twice in the winter and twice in the summer of 2009. Of the 2 764 fish caught, marine-spawned species contributed 42.3%. Freshwater mullet Myxus capensis and Cape moony Monodactylus falciformis were the dominant marine-spawned species at most sites and were capable of surmounting almost all instream barriers. The longitudinal distribution of these species did, however, vary by size class, with the largest individuals being recorded the furthest upstream. The longfin eel Anguilla mossambica was the only species sampled above all instream barriers, including the 4 m high Cleveland Weir. The giant mottled eel Anguilla marmorata was found in low numbers at sites closer to the estuary headwaters. Other marine-spawned species, including Liza tricuspidens and Mugil cephalus (Mugilidae), Argyrosomus japonicus (Sciaenidae), Lithognathus lithognathus and Rhabdosargus holubi (Sparidae), were sampled in low numbers from the site directly below the first instream barrier only, suggesting that this first barrier restricted the access of these species to upstream environments. Freshwater non-native fishes contributed 41.7% to the total catch by numbers. The potential impact of the non-native species as predators and competitors on marine-spawned species in the study area is discussed.Keywords: migration, catadromous, eel, mullet, weir, invasive fishe

TRY plant trait database - enhanced coverage and open access

Plant traits-the morphological, anatomical, physiological, biochemical and phenological characteristics of plants-determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait-based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits-almost complete coverage for 'plant growth form'. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait-environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives

Global patient outcomes after elective surgery: prospective cohort study in 27 low-, middle- and high-income countries.

BACKGROUND: As global initiatives increase patient access to surgical treatments, there remains a need to understand the adverse effects of surgery and define appropriate levels of perioperative care. METHODS: We designed a prospective international 7-day cohort study of outcomes following elective adult inpatient surgery in 27 countries. The primary outcome was in-hospital complications. Secondary outcomes were death following a complication (failure to rescue) and death in hospital. Process measures were admission to critical care immediately after surgery or to treat a complication and duration of hospital stay. A single definition of critical care was used for all countries. RESULTS: A total of 474 hospitals in 19 high-, 7 middle- and 1 low-income country were included in the primary analysis. Data included 44 814 patients with a median hospital stay of 4 (range 2-7) days. A total of 7508 patients (16.8%) developed one or more postoperative complication and 207 died (0.5%). The overall mortality among patients who developed complications was 2.8%. Mortality following complications ranged from 2.4% for pulmonary embolism to 43.9% for cardiac arrest. A total of 4360 (9.7%) patients were admitted to a critical care unit as routine immediately after surgery, of whom 2198 (50.4%) developed a complication, with 105 (2.4%) deaths. A total of 1233 patients (16.4%) were admitted to a critical care unit to treat complications, with 119 (9.7%) deaths. Despite lower baseline risk, outcomes were similar in low- and middle-income compared with high-income countries. CONCLUSIONS: Poor patient outcomes are common after inpatient surgery. Global initiatives to increase access to surgical treatments should also address the need for safe perioperative care. STUDY REGISTRATION: ISRCTN5181700

TRY plant trait database - enhanced coverage and open access

Plant traits—the morphological, anatomical, physiological, biochemical and phenological characteristics of plants—determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait‐based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits—almost complete coverage for ‘plant growth form’. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait–environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives

Review of the projected impacts of climate change on coastal fishes in southern Africa

The coastal zone represents one of the most economically and ecologically important ecosystems on the planet, none more so than in southern Africa. This manuscript examines the potential impacts of climate change on the coastal fishes in southern Africa and provides some of the first information for the Southern Hemisphere, outside of Australasia. It begins by describing the coastal zone in terms of its physical characteristics, climate, fish biodiversity and fisheries. The region is divided into seven biogeographical zones based on previous descriptions and interpretations by the authors. A global review of the impacts of climate change on coastal zones is then applied to make qualitative predictions on the likely impacts of climate change on migratory, resident, estuarine-dependent and catadromous fishes in each of these biogeographical zones. In many respects the southern African region represents a microcosm of climate change variability and of coastal habitats. Based on the broad range of climate change impacts and life history styles of coastal fishes, the predicted impacts on fishes will be diverse. If anything, this review reveals our lack of fundamental knowledge in this field, in particular in southern Africa. Several research priorities, including the need for process-based fundamental research programs are highlighted

Shallow-water, nearshore current dynamics in Algoa Bay, South Africa, with notes on the implications for larval fish dispersal

Nearshore currents play a vital role in the transport of eggs and larval stages of fish. However, little is known about their complexity and the implications for dispersal of fish larvae. The study describes the complexity of the shallow nearshore environment in eastern Algoa Bay, on the south-east coast of South Africa, and its effect on larval fish ecology. An ADCP was used to assess short-term spatial current variability across the nearshore (4–20 m depth) during intensive one-day-transect profiling surveys. Data showing long-term temporal variability was collected half-hourly from a bottom-moored (15–20 m depth) ADCP over the course of one year (May 2006–May 2007). The short-term profiling revealed complexity in both current speed and direction with largely wind-driven flow patterns identified. The long-term data showed that the currents were aligned approximately west/east with prevailing winds and local shoreline. Modal speeds of 8 cm s–1 near the surface (4 m) and 6 cm s–1 near the bottom (14 m) of the water column are much lower than the average swimming speeds of postflexion larvae known to occur in the area. Mean current speed decreased with depth from ~30 cm s–1 (4 m) to ~10 cm s–1 (14 m), suggesting opportunities for depth refuge from current displacement in older larvae. Potential nett displacements were greater during the spring and summer, coinciding with peak fish breeding with passive eggs and early stage larvae travelling distances of up to 475 km near the surface of the water column. These maximum dispersal distances recorded during the present study differ considerably by half that from other calculations made for the area, highlighting a data error in a previous study. These predictions provide preliminary indications of potential transport from a point source and do not factor in anomalous local oceanography, benthic topographic impediments to transport or the complexities of larval fish behaviour.Keywords: connectivity, dispersal, ichthyoplankton, larval fish behaviour, marine protected area, nearshore currentsAfrican Journal of Marine Science 2013, 35(2): 269–28