Background paper on the international seafood trade and poverty

(121 p.)

Use of Sediment Bioassays to Verify Efficacy of Caulerpa taxifolia Eradication Treatments

Infestations of the marine macrophytic alga Caulerpa taxifolia were discovered in Agua Hedionda Lagoon, California in 2000. Rapid response actions included containment under pvc tarps coupled with injection of liquid sodium hypochlorite. To assess the efficacy of these treatments, replicated sediment cores were removed from representative treated sites and transferred to grow-out facilities. Similar cores from uninfested (control) sediments were removed, inoculated with viable explants of C. taxifolia and placed in grow-out facilities. Results from two sampling periods (1 year, 2 years post-treatment) showed that no viable C. taxifolia emerged in cores, and that inoculated “control” sediments supported normal growth. Eelgrass ( Zostera marina L.) seedlings emerged from native seed-banks in “treated” cores, which also supported growth of some invertebrates (annelid worms and hydroids). This study provided essential verification of C. taxifolia eradication efforts, and demonstrates the feasibility of incorporating quality control/quality assurance components in rapid response actions. Results of this study also suggest that seeds of eelgrass are viable for at least two years. (PDF has 9 pages.)

Encouraging them to come to us: changing the way that information is made available to farmers

Recommendations for changes to service provision and fisheries policy in support of poverty alleviation emerged recently in India from a process know as facilitated advocacy (see Case Study SI 2) that helped to negotiate and support a role for poor people and their service providers, to contribute to changes in services and policies. Two of the key recommendations to emerge from farmers and fishers, which were prioritized by Fisheries Departments, were to change the way that information is made available and to simplify procedures for accessing government schemes and bank loans. This case which identifies the origin of these recommendations to change the way that information is made available, shows how different models of the concept have emerged, and follows the development of the One-stop Aqua Shops (OAS) in the eastern Indian states of Jharkhand, Orissa and West Bengal, that represent a new and vital tier in communications in aquaculture. (12 p.)

Ras Behari’s guide to buying fish seed

Document contains 4 pages.

Facilitated advocacy: supporting farmers to have a voice in policy making and the development of service provision

Listening to people, especially those who are poor, and involving them in policy making and decisions about service delivery processes are logical steps in building better services and improving policies aimed at poverty alleviation. This case describes a facilitated advocacy that helped to negotiate and support a role for poor people who farm and fish, to contribute recommendations for changes in services and policies that impact on their lives. The national Government of India’s Department of Animal Husbandry and Dairying and the Indian Council for Agricultural Research, both in the capital Delhi, have been linking with farmers and fishers and state government officials in the eastern states of Jharkhand, Orissa and West Bengal, in partnership with the STREAM Initiative of the intergovernmental Network of Aquaculture Centers in Asia Pacific and with the support of the UK Government Department for International Development, Natural resources Systems Program supporting farmers to have a voice(13 p.)

STREAM Journal, Vol. 1, No. 1, pp. 1-12. January-March 2002

CONTENTS: Learning from each other about conflict, by Ronet Santos. E-learning to support knowledge sharing in aquatic resources, by Robert T. Raab and Jonathan Woods. Livelihood strategies, gender and participation in aquaculture: findings from participatory research in northwestern Sri Lanka, by Lindsay J. Pollock and David C. Little. Farming of giant tiger shrimp in northern central Vietnam, by Jesper Clausen. Interacting with stakeholders and policy-makers, by To Phuc Tuong. The role of nutrition communications in meeting the nutritional challenges of the Asia-Pacific region, by Georgina Cairns. (PDF has 16 pages.)

Effect of Aquathol K Treatments on Activity Patterns of Largemouth Bass in Two Coves of Lake Seminole, Georgia

Thirty largemouth bass ( Micropterus salmoide s Lacepde) were implanted with radio tags in late October 2003 in two coves of Lake Seminole, Georgia, and tracked over a 24-hour period about every 10 days to determine their response to herbicide application. After five weeks of tracking, hydrilla ( Hydrilla verticillata Royle) in each cove was treated in early December 2003 with dipotassium salt of endothall (Aquathol K; 7-oxabicyclo [2.2.1] heptane-2,3-dicarboxylic acid) at a rate of 3.5 ppm. Largemouth bass were tracked during application and tracking continued for three months post treatment to assess effects of herbicide treatment on activity patterns. The treatment in Desser Cove successfully reduced hydrilla in approximately half the cove. However, the treatment in Peacock Lake completely eliminated all submersed aquatic vegetation (SAV) by April 2004. Movement and activity centers remained similar between treatment periods in Desser Cove, but increased after treatment in Peacock Lake. Depth occupied by telemetered fish decreased after Aquathol K treatment in both coves. In general, behavior of largemouth bass did not change appreciably during treatment, and only minor changes were observed in the posttreatment period in Peacock Lake, where all SAV was eliminated. Fish showed little attraction to or movement away from treatment areas, and fish migration from either cove was nil after treatment. Application of Aquathol K and subsequent reduction of SAV had little effect on largemouth bass behavior or movement. (PDF has 8 pages.)

2,4-D and Mycoleptodiscus terrestris for control of Eurasian Watermilfoil

Growth chamber studies were conducted to evaluate the impact of an indigenous fungal pathogen, Mycoleptodiscus terrestris (Gerd.) Ostazeski, and the herbicide 2,4-D applied alone and in combination with one another, on the growth of a nuisance submersed plant, Eurasian watermilfoil ( Myriophyllum spicatum L.)(PDF has 6 pages.)

Effects of pH on Growth of Salvinia molesta Mitchell

Growth of giant salvinia ( Salvinia molesta Mitchell) under different pH regimes was examined at the Lewisville Aquatic Ecosystem Research Facility (LAERF) in Lewisville, Texas.(PDF has 5 pages.)

Seed Longevity of Melaleuca quinquenervia: A Burial Experiment in South Florida

Burial and removal techniques with seed bags were used to examine the viability and longevity of Melaleuca quinquenervia seeds at four field sites representing different soil types and hydrological conditions in South Florida. Seed viability was determined over different burial durations in the soil through a combination of germination tests and 2,3,5-triphenyl- tetrazolium chloride (TTC) treatments. Control seeds kept dry at 25 C in the laboratory maintained same viability of ca. 15% over the 3-year study. In the field, seed viability decreased with increased burial duration.(PDF has 4 pages.)

Assessment Method for Leaf Litters Allelopathic Effect on Cyanobacteria

A new bioassay technique combining leaf disk and softagar over-layer methods was developed to investigate the allelopathic effect of deciduous leaf litters on the growth of cyanobacteria ( Microcystis aeruginosa Kütz.). Bioactive substances exuded from leaf disks caused inhibitory plaques on the agar plate containing cyanobacteria , and the rate of diffusion depended on the specific leaf disk area. Most of the leaf litters collected around reservoirs in Japan showed inhibitory activity to M. aeruginosa , with Rhus trichocarpa Miq., Quercus variabilis Blume and Mallotus japonicus (Thunb.) Muell. Arg. being the strongest among the 22 tested species.(PDF has 4 pages.)

Population Dynamics of Cyrtobagous salviniae on Common Salvinia in South Florida

Common salvinia (Salvinia minima Baker) is an exotic floating fern that has been in the U.S. from at least 1928(Small 1931). Its pest status in Florida is less clear perhaps due to the presence of the specialized herbivore Cyrtobagous salviniae (Coleoptera: Curculionidae). Our objective was to sample populations of adult C. salviniae in south Florida in order to assess temporal abundance and estimate density on common salvinia. (PDF has 4 pages.)

Manual Control of Phragmites australis on Pondshores of Cape Cod National Seashore, Masachusetts, USA

The non-native, invasive genotype of the common reed ( Phragmites australis (Cav.) Trin. ex Steudel) has become a problem of significant proportions throughout wetlands of North America (Saltonstall 2001). Although attempts to suppress or eradicate Phragmites have utilized a wide variety of techniques, herbicides have generally been most effective (Marks et al. 1994). In the spring, mid-summer, and late summer of 2003, we attempted to opportunistically control Phragmites in five freshwater ponds within Cape Cod National Seashore (CCNS) by repeatedly severing stems underwater, at ground level.(PDF has 4 pages.)

Remote Sensing of Giant Reed with QuickBird Satellite Imagery

QuickBird high resolution (2.8 m) satellite imagery was evaluated for distinguishing giant reed ( Arundo donax L.) infestations along the Rio Grande in southwest Texas. (PDF has 5 pages.)

Comparative Response of Two Hydrilla Strains to Fluridone

Experiments were conducted in a controlled-environmental growth chamber to evaluate the response of two strains of the invasive submersed plant Hydrilla verticillata (L.f.) Royle to fluridone (1-methyl-3-phenyl-5-[3-trifluoromethyl)phenyl]- 4(1H)-pyridinone). (PDF has 6 pages.)