Environmental hazards to small scale fisheries resources management in Nigeria

This paper examined the environmental hazards limiting sustainable small-scale fisheries development in Nigeria. Observation has showed that hazards range from pollution of the aquatic habitats by domestic and urban sewage and garbage, agro-chemicals, industrial pollutants, crude oil spillage etc. In an attempt to maximize catch, many migrant and part-time fisher folks indulge in highly destructive and obnoxious fishing practices with adverse impact on fisheries resources. These have constituted significant environmental hazards. Discharges of waste from aquacultural practices in to rivers and lakes have also been identified as sources of environmental hazards. Some aquatic weeds such as water hyacinth are sources of hazards. The effects of environmental hazards on small-scale fisheries resources may be direct arising from the toxicity of pollutants or indirect as a result of ecosystem modification. Some of the effects of pollutants on the aquatic environment and fish have been discussed in the paper

Preparing for and adapting to climate change impacts: Next steps for the Washington state department of National Resources Aquatic Resources Program

In response to a growing body of research on projected climate change impacts to Washington State’s coastal areas, the Washington State Department of Natural Resources’ (DNR) Aquatic Resources Program (the Program) initiated a climate change preparedness effort in 2009 via the development of a Climate Change Adaptation Strategy (the Strategy)i. The Strategy answers the question “What are the next steps that the Program can take to begin preparing for and adapting to climate change impacts in Washington’s coastal areas?” by considering how projected climate change impacts may effect: (1) Washington’s state-owned aquatic landsii, (2) the Program’s management activities, and (3) DNR’s statutorily established guidelines for managing Washington’s state-owned aquatic lands for the benefit of the public. The Program manages Washington’s state-owned aquatic lands according to the guidelines set forth in Revised Code of Washington 79-105-030, which stipulates that DNR must manage state-owned aquatic lands in a manner which provides a balance of the following public benefits: (1) Encouraging direct public uses and access; (2) Fostering water-dependent uses; (3) Ensuring environmental protection; (4) Utilizing renewable resources. (RCW 79-105-030) The law also stipulates that generating revenue in a manner consistent with these four benefits is a public benefit (RCW 79-105-030). Many of the next steps identified in the Strategy build off of recommendations provided by earlier climate change preparation and adaptation efforts in Washington State, most notably those provided by the Preparation and Adaptation Working Group, which were convened by Washington State Executive Order 70-02 in 2007, and those made in the Washington Climate Change Impacts Assessment (Climate Impacts Group, 2009). (PDF contains 4 pages)

Toxicity of linear alkylbenene sulphonate (LAS) detergent, to Clarias gariepinus fingerlings

The acute toxicity of Linear Alkylbenzene Sulphonate (LAS) detergent to Clarias gariepinus fingerlings was investigated using static bioassays and continous aeration over a period of 96h. The 96h LC sub(50) was determined as 24.00mgL super(-1). During the exposure period, the test fish exhibited several behavioural changes before death such as restlessness, rapid swimming, loss of balance, respiratory distress and haemorrhaging of gill filaments amongst others. Opercula ventilation rate as well as visual examination of dead fish indicates lethal effects of the detergent on the fish. Water quality examination showed increase in pH from 6.55 to the alkaline, death point of 10.55. There was also a remarkabel rise of alkalinity from 20.00mgL super(-1) to 52.50mgL super(-1)

International sources of fisheries information to enhance fish production, poverty alleviation and food security in Nigeria and developing Nigerian Fisheries and Aquatic Sciences Database

The paper viewed the decline in information provision in Nigeria to poor library development, which could be attributed to poor funding. The consequence is that current journal and books are not available in nigerian fisheries libraries. Information which can be regarded as the first factor of production on which other factors like land, labour and capital depend, can only be provided at the right time when libraries are better founded. For now if there must be increase in fish production, poverty alleviation and food security in Nigeria, our fisheries scientists and policy makers will have to rely on international sources of information using the advantage of internet connectivity. Some of such sources discussed in this paper are ASFA, AGORA, FAO DOAJ, FISHBASE, IAMSLIC, INASP, INASP-PERI, INASP-AJOL, ODINAFRICA, SIFAR, WAS, and ABASFR. However, reliance on international sources must not be at the total neglect of harnessing nigerian fisheries information. For the Nigerian Fisheries and Aquatic Sciences Database being developed by NIFFR to attain an international status like those enumerated above, scientists and publishers are requested to take the pain of depositing copies of their publications with NIFFR for inclusion in the Database

Utilization of some aquatic macrophytes in Nigeria in-land water bodies: a review

Aquatic vegetation is an essential component of the aquatic ecosystem with both positive and negative implications on the water body. Efforts are always made to curtail the excessive growth of aquatic plants in order to prevent them from becoming a nuisance in the ecosystem. One of the ways of solving such problem is the positive economic use of such plants. Utilization as a method of weed control within the aquatic ecosystem is considered to be one of the safest methods of weed control as this provides the riparian communities double advantages in terms of save environment and personal benefits of the plant. The flora diversity of freshwater and brackish environments posses a great potential to both man and higher animals alike. Due to this fact, this paper attempt to review the exploited and unexploited aquatic plants resources of many of our water bodies in Nigeria both economica/ly and socially, to the populace. Recommendations are also advanced for further studies that will enhance sound management of the resources for maximum benefits and sustainability

Pathways for the uptake of dissolved organic matter (DOM) by aquatic animals

In this article, pathways from freshwater and marine environments are described. DOM is defined operationally as all the organic compounds which pass through a filter of pore size 0.45 microm., those retained on the surface of the filter being particulate organic matter (POM). DOM can be taken up directly by animals by transfer across the body wall, but more commonly DOM is obtained from ingested food. Once ingested POM from food particles are broken down in the gut, small molecules of DOM are released for transfer across the gut wall. Some ingested particles are attacked by micro-organisms living in the gut, thereby making the DOM available to the host animal. The importance of the microbial loop is discussed, as well as aggregation processes between the fractions of DOM which are more obviously particulate in nature. (DBO)

Aquatic insects as target organisms for the study of effects of projected climate change in the British Isles

The chief objectives of this brief review are to collate and synthesise quantitative information on the temperature requirements of aquatic insects, and to identify species, and groups of species, that could be useful indicators of climate change and predictors of the ecological effects of change. It arose from the first phase of the Terrestrial Initiative in Global Environmental Research (TIGER), a five-year, NERC Community Programme on the role of the terrestrial biosphere in the science of global change. This phase involved the identification of criteria for selecting species suitable for the study of effects of projected climate change in the British Isles. Field and laboratory studies are reviewed, and criteria for selection of species for future research are suggested. The literature survey shows that no species of aquatic insect can be found to meet all three criteria, but information on the British stoneflies and their eggs already satisfies two of them.

The aquatic biota of the now extinct lacustrine complex of the Mexico basin

The commonest organisms of the original Mexico lake complex are listed, including those that exist today in the Lago Viejo. In addition, a brief hydraulic history of this endorheic basin is given.

Temperature, organic matter and the sustainability of aquatic systems

Changes in sustainability of aquatic ecosystems are likely to be brought about by the global warming that has been widely predicted. In this article, the effects of water temperature on water-bodies (lakes, oceans and rivers) are reviewed followed by the effects of temperature on aquatic organisms. Almost all aquatic organisms require exogenous heat before they can metabolise efficiently. An organism that is adapted to warm temperatures will have a higher rate of metabolism of food organisms and this increases feeding rate. In addition, an increase in temperature raises the metabolism of food organisms, so food quality can be altered. Where populations have a different tolerance to temperature the result is habitat partitioning. One effect of prolonged high temperature is that it causes water to evaporate readily. In the marine littoral this is not an important problem as tides will replenish water in pools. Small rain pools are found in many tropical countries during the rainy season and these become incompletely dried at intervals. The biota of such pools must have resistant stages within the life cycle that enable them to cope with periods of drying. The most important potential effects of global warming include (i) the alteration of existing coastlines, (ii) the development of more deserts on some land masses, (iii) higher productivity producing higher crop production but a greater threat of algal blooms and (iv) the processing of organic matter at surface microlayers.

The distribution of aquatic bugs (Hemiptera-Heteroptera) in Scotland

Data on the distribution of aquatic bugs in Scotland was compiled with a widely-used biological recording software called RECORDER supplemented by a mapping program (DMAP) and a program that linked the two. Status lists are given with a brief account of the distribution of each species. Common and widespread species are listed in group one, including Velia caprai and Gerris lacustris, with less common species in group two such as Hydrometra stagnorum and Microvelia reticulata. Rare, uncommon or under-recorded species are also listed. These include Hebrus ruficeps, Gerris najas and Cymatia coleoptrata.

Aquatic ecology, economy and society: the place of aquatic ecology in the sustainability agenda

This article explores aspects of sustainability and the importance of sustainable development, including the place of the crucially important resource of fresh water and of freshwater ecosystems. It examines the treatment of natural resources by the economic system that underpins global business, outlines some progress towards more sustainable approaches to business, and recommends steps to re-establish science as the driver of wise policies that contribute to sustainable development.

Testable models of aquatic systems: A NERC special topic for integrating experiments and modelling

A major part of the support for fundamental research on aquatic ecosystems continues to be provided by the Natural Environment Research Council (NERC). Funds are released for ”thematic” studies in a selected special topic or programme. ”Testable Models of Aquatic Ecosystems” was a Special Topic of the NERC, initiated in 1995, the aim of which was to promote ecological modelling by making new links between experimental aquatic biologists and state-of-the-art modellers. The Topic covered both marine and freshwater systems. This paper summarises projects on aspects of the responses of individual organisms to the effects of environmental variability, on the assembly, permanence and resilience of communities, and on aspects of spatial models. The authors conclude that the NERC Special Topic has been highly successful in promoting the development and application of models, most particularly through the interplay between experimental ecologists and formal modellers.

Heated aquatic microcosms for climate change experiments

Ponds and shallow lakes are likely to be strongly affected by climate change, and by increase in environmental temperature in particular. Hydrological regimes and nutrient cycling may be altered, plant and animal communities may undergo changes in both composition and dynamics, and long-term and difficult to reverse switches between alternative stable equilibria may occur. A thorough understanding of the potential effects of increased temperature on ponds and shallow lakes is desirable because these ecosystems are of immense importance throughout the world as sources of drinking water, and for their amenity and conservation value. This understanding can only come through experimental studies in which the effects of different temperature regimes are compared. This paper reports design details and operating characteristics of a recently constructed experimental facility consisting of 48 aquatic microcosms which mimic the pond and shallow lake environment. Thirty-two of the microcosms can be heated and regulated to simulate climate change scenarios, including those predicted for the UK. The authors also summarise the current and future experimental uses of the microcosms.

Angling and species richness of aquatic macrophytes in ponds

Ponds are unjustly neglected habitats. This paper aims to raise awareness of the potential interaction between angling and the macrophyte vegetation of ponds. The work described by the author followed on from a study of 57 ponds in East Yorkshire, northeast England, by Linton & Goulder (2000). They found that the species richness of aquatic vascular plants (macrophytes) is greater in ponds that are used for angling and suggest that to some extent there are more species because disturbance by anglers leads to greater habitat diversity. This article describes how the hypothesis was tested by comparing species richness at fished sites with that at non-fished sites around the margins of ponds in two localities in East Yorkshire. The localities were investigated during August-September 1999.