The Atlantic and Gulf Menhaden Purse Seine Fisheries: Origins, Harvesting Technologies, Biostatistical Monitoring, Recent Trends in Fisheries Statistics, and Forecasting

With its genesis in New England during the 1800's, the purse seine fishery for Atlantic menhaden, Brevoortia tyrannus, expanded south and by the early 1900's ranged the length of the eastern seaboard. The purse seine fishery for Gulf menhaden. B. patronus, is of relatively recent development, exploitation of the stock beginning in the late 1940's. Landings from both fisheries annually comprise 35-40% of the total U. S. fisheries landings, ranking menhaden first in terms of volume landed. Technological advances in harvesting methods, fish-spotting capabilities, and vessel designs accelerated after World War II, resulting in larger, faster, and wider-ranging carrier vessels, improved speed and efficiency of the harvest, and reduction in labor requirements. Chief products of the menhaden industry are fish meal, fish oil, and solubles, but research into new product lines is underway. Since 1955 on the Atlantic coast and 1964 on the Gulf coast, the NMFS has monitored the fisheries for biostatistical data. Annual data summaries of numbers-of-fish-at-age harvested, catch tonnage, and fishing effort of the fleet form the basis of routine stock assessments and annual catch forecasts to industry for the upcoming fishing season. After landings declined in the 1960's, the Atlantic menhaden stock has recovered through the 1970's and 1980's. Exceptional year classes of Gulf menhaden in recent years account for record landings during the 1980's.

Economic and social impacts of Integrated Aquaculture-Agriculture technologies in Bangladesh

This study estimated the adoption rate of integrated aquaculture-agriculture (IAA) technologies in Bangladesh and their impact on poverty and fish and food consumption in adopting households. We used a novel, simulation-based approach to impact assessment called Tradeoff Analysis for Multi-Dimensional Impact Assessment (TOA-MD). We used the TOA-MD model to demonstrate how it is possible to use available data to estimate adoption rates in relevant populations, and to quantify impacts on distributional outcomes such as poverty and food security, thus demonstrating ex ante the potential for further investment in technology dissemination. The analysis used baseline and end-of-project survey data from WorldFish-implemented Development of Sustainable Aquaculture Project (DSAP), promoting IAA. This dataset was used to simulate adoption and assess its impacts on poverty and food security in the target population. We found that, if adopted, IAA had a significant positive impact on reducing poverty and improving food security and income.

Systems aspects of optical technologies for use in datacommunications

This paper reviews the development of system techniques using advanced modulation formats that have arisen in recent years for use in datacommunications. Simulations are provided to allow comparison of the emerging schemes. © 2011 Optical Society of America.

Er3+-doped glass-polymer composite thin films fabricated using combinatorial pulsed laser deposition

Siloxane Polymer exhibits low loss in the 800-1500 nm range which varies between 0.01 and 0.66 dB cm1. It is for such low loss the material is one of the most promising candidates in the application of engineering passive and active optical devices [1, 2]. However, current polymer fabrication techniques do not provide a methodology which allows high structurally solubility of Er3+ ions in siloxane matrix. To address this problem, Yang et al.[3] demonstrated a channel waveguide amplifier with Nd 3+-complex doped polymer, whilst Wong and co-workers[4] employed Yb3+ and Er3+ co-doped polymer hosts for increasing the gain. In some recent research we demonstrated pulsed laser deposition of Er-doped tellurite glass thin films on siloxane polymer coated silica substrates[5]. Here an alternative methodology for multilayer polymer-glass composite thin films using Er3+ - Yb3+ co-doped phosphate modified tellurite (PT) glass and siloxane polymer is proposed by adopting combinatorial pulsed laser deposition (PLD). © 2011 IEEE.

An investigation of survey technologies and modeling techniques for improving deepwater surveys of nonindigenous species in the Northwestern Hawaiian Islands

Nonindigenous species (NIS) are a major threat to marine ecosystems, with possible dramatic effects on biodiversity, biological productivity, habitat structure and fisheries. The Papahānaumokuākea Marine National Monument (PMNM) has taken active steps to mitigate the threats of NIS in Northwestern Hawaiian Islands (NWHI). Of particular concern are the 13 NIS already detected in NWHI and two invasive species found among the main Hawaiian Islands, snowflake coral (Carijoa riseii) and a red alga (Hypnea musciformis). Much of the information regarding NIS in NWHI has been collected or informed by surveys using conventional SCUBA or fishing gear. These technologies have significant drawbacks. SCUBA is generally constrained to depths shallower than 40 m and several NIS of concern have been detected well below this limit (e.g., L. kasmira – 256 m) and fishing gear is highly selective. Consequently, not all habitats or species can be properly represented. Effective management of NIS requires knowledge of their spatial distribution and abundance over their entire range. Surveys which provide this requisite information can be expensive, especially in the marine environment and even more so in deepwater. Technologies which minimize costs, increase the probability of detection and are capable of satisfying multiple objectives simultaneously are desired. This report examines survey technologies, with a focus on towed camera systems (TCSs), and modeling techniques which can increase NIS detection and sampling efficiency in deepwater habitats of NWHI; thus filling a critical data gap in present datasets. A pilot study conducted in 2008 at French Frigate Shoals and Brooks Banks was used to investigate the application of TCSs for surveying NIS in habitats deeper than 40 m. Cost and data quality were assessed. Over 100 hours of video was collected, in which 124 sightings of NIS were made among benthic habitats from 20 to 250 m. Most sightings were of a single cosmopolitan species, Lutjanus kasmira, but Cephalopholis argus, and Lutjanus fulvus, were also detected. The data expand the spatial distributions of observed NIS into deepwater habitats, identify algal plain as an important habitat and complement existing data collected using SCUBA and fishing gear. The technology’s principal drawback was its inability to identify organisms of particular concern, such as Carijoa riseii and Hypnea musciformis due to inadequate camera resolution and inability to thoroughly inspect sites. To solve this issue we recommend incorporating high-resolution cameras into TCSs, or using alternative technologies, such as technical SCUBA diving or remotely operated vehicles, in place of TCSs. We compared several different survey technologies by cost and their ability to detect NIS and these results are summarized in Table 3.