Technologies and Methodologies for the Detection of Harmful Algae and Their Toxins, St Petersburg, Florida, Oct 22-24 2008 : workshop proceedings

The Alliance for Coastal Technologies (ACT) Workshop "Technologies and Methodologies for the Detection of Harmful Algae and their Toxins" convened in St. Petersburg, Florida, October 22- 24, 2008 and was co-sponsored by ACT (http://act-us.info); the Cooperative Institute for Coastal and Estuarine Environmental Technology (CICEET, http://ciceet.unh.edu); and the Florida Fish and Wildlife Conservation Commission (FWC, http://www.myfwc.com). Participants from various sectors, including researchers, coastal decision makers, and technology vendors, collaborated to exchange information and build consensus. They focused on the status of currently available detection technologies and methodologies for harmful algae (HA) and their toxins, provided direction for developing operational use of existing technology, and addressed requirements for future technology developments in this area. Harmful algal blooms (HABs) in marine and freshwater systems are increasingly common worldwide and are known to cause extensive ecological, economic, and human health problems. In US waters, HABs are encountered in a growing number of locations and are also increasing in duration and severity. This expansion in HABs has led to elevated incidences of poisonous seafood, toxin-contaminated drinking water, mortality of fish and other animals dependent upon aquatic resources (including protected species), public health and economic impacts in coastal and lakeside communities, losses to aquaculture enterprises, and long-term aquatic ecosystem changes. This meeting represented the fourth ACT sponsored workshop that has addressed technology developments for improved monitoring of water-born pathogens and HA species in some form. A primary motivation was to assess the need and community support for an ACT-led Performance Demonstration of Harmful Algae Detection Technologies and Methodologies in order to facilitate their integration into regional ocean observing systems operations. The workshop focused on the identification of region-specific monitoring needs and available technologies and methodologies for detection/quantification of harmful algal species and their toxins along the US marine and freshwater coasts. To address this critical environmental issue, several technologies and methodologies have been, or are being, developed to detect and quantify various harmful algae and their associated toxins in coastal marine and freshwater environments. There are many challenges to nationwide adoption of HAB detection as part of a core monitoring infrastructure: the geographic uniqueness of primary algal species of concern around the country, the variety of HAB impacts, and the need for a clear vision of the operational requirements for monitoring the various species. Nonetheless, it was a consensus of the workshop participants that ACT should support the development of HA detection technology performance demonstrations but that these would need to be tuned regionally to algal species and toxins of concern in order to promote the adoption of state of the art technologies into HAR monitoring networks. [PDF contains 36 pages]

Assessment of post-harvest losses in Nigeria fishery: the Kainji Lake model

The paper provides a description of a methodology used for quantitative assessment of post harvest losses in the Kainji Lake Fishery (Nigeria). The sample population was made up of 314 fisherfolk, 115 processors, 125 fish buyers and 111 fish sellers. For the determination of handling losses, 24,839 fishes weighing 2,389.31 kg belonging to 43 species were examined of which 10% by number and 9% by weight deteriorated at checking and 4% by number and 3% by weight at landing. Processing losses recorded 22% by number and 16% by weight deteriorated prior to and during smoking with the traditional 'Banda' kiln. During marketing, 16% of fish sold had deteriorated and 6% by weight of fish bought also deteriorated, mainly due to insect infestation during storage. Based on the 1995 yield estimate for Kainji Lake fishery, approximately 1000 tons of fish estimated at 80 million Naira were lost during handling alone. This figure would be much higher if the level of losses during processing and marketing are included. This assessment technique is recommended for use in obtaining quantifiable data on post harvest losses from other water bodies in Nigeria

A preliminary investigation into the post harvest losses of fish in Shiroro Lake area

The findings are presented of a study conducted to assess the post harvest losses in Shiroro Lake, Nigeria. The major objectives were to identify and quantify the types of losses, to provide recommendations that would enhance formulation of policy guidelines for utilization and exploitation of the declining fishery resources of the lake

Post harvest losses in the fisheries of Kainji Lake

An assessment is given of the post-harvest losses in the Lake Kainji fisheries of Nigeria. The study focussed on quantifiable information on post-harvest technology and post-harvest losses from fisherfolk, fish processors and fish traders operating within the Kainji Lake basin. The information was obtained from questionnaires sent to a total of 665 respondents, comprising 317 fishermen, 115 fish processors, 125 fish buyers, and 111 fish sellers in 45 fishing villages and collection centres within the lake basin. Considering the total catch from gillnets, longlines, traps and cast nets estimated at 14,000 in 1995 about 1,000 t of fish was either discarded or lost value due to spoilage during handling by fisherfolk. Assuming an average prices of 80 Naira/kg of fish, the loss to the economy amounted to 80 million Naira annually. Appropriate recommendations are made to significantly reduce post-harvest losses in the Kainji Lake fishery. (PDF contains 91 pages)

An investigation into the potential losses of fish on the filter plates at the Hodder Water Treatment Works Stocks Reservoir

Stocks Reservoir is situated amidst the Forest of Bowland in the upper reaches of the old river valley of the Hodder. The reservoir was built in 1927 for the Fylde Water Board who primarily supplied water to Blackpool. The objective of this study is to assess the degree and likelihood of fish ingress onto the fish plates at the present and proposed stocking densities. An additional aim is to evaluate the operational implications, and if necessary suggest methods of alleviating the problem. Three spheres of study have been undertaken to achieve these objectives, these being: 1. To selectively stock the reservoir and monitor the angling club catches in order to assess the total population, relating it to fish plate losses and proposed stocking densities. 2. To monitor the fish taken from the fish plates and assess the reasons for their ingress. 3. To study the draw off tower and fish plates, and suggest ways of ameliorating or halting the loss of fish and consequent operational problems.

A relational database of post-harvest fish losses

The article describes FISHLOSS, a database of post-harvest fish losses devised by the Natural Resources Institute (NRI), UK. The database contains 450 records of post-harvest fish losses from 150 sources. The majority of the estimates are shelf-life estimates. Designed to be a reference for people studying post-harvest fish losses, it draws attention to areas requiring future research to identify significant losses and the factors which cause them. All researchers and users are encouraged to send NRI their own estimates for inclusion in revised versions of FISHLOSS.

Climatic indicators in an ice core from the Yukon [abstract]

EXTRACT (SEE PDF FOR FULL ABSTRACT): Stable isotope data obtained from snow and ice cores retrieved from an altitude of 5340m on Mt. Logan (60°30'N; 140°36'W) indicate that "isotopic seasons" are not generally in phase with calendar seasons. The former are phase lagged with respect to the latter by up to several months and appear to be correlated with SST'S and ocean heat transfer curves and/or the position of the Aleutian low rather than with air temperature or the temperature difference between the ocean surface and the core site.

Stratigraphy and chronology of Holocene marine sedment core from the California continental borderland and their paleoceanographic/paleoclimatic significance [abstract]

EXTRACT (SEE PDF FOR FULL ABSTRACT): Paleomagnetic secular variation (PSV) records have been recovered from three marine sediment cores from Santa Catalina basin, California continental borderland, in order to more accurately date these late Quaternary sediments. ... The sedimentation rates derived from the time/depth curves suggest a constant rate of 20-25 cm/ky for the last 6700 years throughout Santa Catalina basin, and more variable rates (but constant within each core) of 13-86 cm/ky prior to 6700 ybp. The sedimentation rates prior to 6700 ybp are lowest in the southcentral portion of the basin and systematically increase toward the north end of the basin. These results suggest that 6700±300 ybp marks a major change in paleoceanographic processes within Santa Catalina basin.

Streamflow and La Niña event relationships in the ENSO-streamflow core areas

EXTRACT (SEE PDF FOR FULL ABSTRACT): The high index phase of the Southern Oscillation (SO), La Niña, has not been given as much attention as its counterpart, the low index phase of the SO, El Niño. One reason may be related to the fact that many similarities exist among El Niño events but not among La Niña events. ... In this study, we focus on the influences of La Niña phenomena on streamflow anomalies ... to explore the SO-related signal over the United States.

Yield- and biomass-per-recruit analysis for rotational fisheries, with an application to the Atlantic sea scallop (Placopecten magellanicus)

A general model for yield-per-recruit analysis of rotational (periodic) fisheries is developed and applied to the sea scallop (Placopecten magellanicus) fishery of the northwest Atlantic. Rotational fishing slightly increases both yield- and biomass-per-recruit for sea scallops at FMAX. These quantities decline less quickly when fishing mortality is increased beyond FMAX than when fishing is at a constant rate. The improvement in biomass-per-recruit appears to be nearly independent of the selectivity pattern but increased size-at-entry can reduce or eliminate the yield-per-recruit advantage of rotation. Area closures and rotational fishing can cause difficulties with the use of standard spatially averaged fishing mortality metrics and reference points. The concept of temporally averaged fishing mortality is introduced as one that is more appropriate for sedentary resources when fishing mortality varies in time and space.

Initial global perspective of climate for the last thousand years: the ice core record

Climatic and environmental records from low, middle, and high latitude ice cores greatly increase our knowledge of the course of past events. This historical perspective is essential to predict climatic oscillations, dominated as they may be by increasing greenhouse gas concentrations. Forcing factors, internal and external, that have operated in the past will continue to influence the course of events.

Economic losses/gains attributed to the water hyacinth

This is the report of a research study aimed at providing an understanding of the fishing communities and institutions about the water hyacinth problem and how it impacts on their activities. Its also provides strategies for sustainable control of the weed. The research reports are intended to disseminate the findings of the studies carried out under the Socio-economics Sub-component of LVEMP to a wide spectrum of users, including policy makers, stakeholders and researchers.

Water imbibition and thawing losses from frozen prawn meat

Prawn meat which was never in contact with ice or water prior to freezing was frozen at -30°C and was studied up to six months of storage at -23°C for thawing losses and cooked characteristics of the thawed material. Thawing loss was nil in unwashed samples after three days of storage and it gradually increased to 6.6% after 6 months compared to 6.0 and 18.2% in the washed samples during the same periods. It is inferred that the high thawing losses observed in commercial frozen prawn meat immediately after freezing may be mainly an after effect of the water imbibed during the pre-freezing stages. During frozen storage, the changes in texture observed by sensory methods on the cooked product were more in the washed sample indicating that the imbibed water or constituents washed out of the tissue play an important role in textural changes in prawn meat during frozen storage.

Year-round and rotational freshwater prawn, Macrobrachium rosenbergii and paddy farming: soil quality, production and economics

A study was carried out at five upazillas (Dumuria, Fakirhat, Pirojpur sadar, Gopalgonj sadar and Kalia) of five southern districts of Khulna, Bagerhat, Pirojpur, Gopalgonj and Narail to understand the comparative production performance and any effect on soil quality in case of year-round golda (Macrobrachium rosenbergii), alternate prawn-paddy and year-round paddy farming. A direct interview of 55 farmers was taken, using pretested questionnaire, and soil samples were taken from selected farms before and after each crop. Among the five upazillas, farmers in Gopalgonj sadar and Kalia are not practicing year-round golda. Rotational golda-paddy farming has been recorded to result in maximum profit, with the highest of Tk. 310,912/ha/year in 2003 at Dumuria. Only paddy farming is less profitable than other two cropping patterns, irrespective of study sites. The nutrient status of soil in rotational golda and paddy farming has been found improved, compared to that of only golda or paddy farming.