Underwater Passive Acoustic Monitoring for Remote Regions, Hawaii Institute of Marine Biology, Coconut Island, Hawaii, February 7-9, 2007: workshop proceedings

The Alliance for Coastal Technologies (ACT) convened a workshop, sponsored by the Hawaii-Pacific and Alaska Regional Partners, entitled Underwater Passive Acoustic Monitoring for Remote Regions at the Hawaii Institute of Marine Biology from February 7-9, 2007. The workshop was designed to summarize existing passive acoustic technologies and their uses, as well as to make strategic recommendations for future development and collaborative programs that use passive acoustic tools for scientific investigation and resource management. The workshop was attended by 29 people representing three sectors: research scientists, resource managers, and technology developers. The majority of passive acoustic tools are being developed by individual scientists for specific applications and few tools are available commercially. Most scientists are developing hydrophone-based systems to listen for species-specific information on fish or cetaceans; a few scientists are listening for biological indicators of ecosystem health. Resource managers are interested in passive acoustics primarily for vessel detection in remote protected areas and secondarily to obtain biological and ecological information. The military has been monitoring with hydrophones for decades;however, data and signal processing software has not been readily available to the scientific community, and future collaboration is greatly needed. The challenges that impede future development of passive acoustics are surmountable with greater collaboration. Hardware exists and is accessible; the limits are in the software and in the interpretation of sounds and their correlation with ecological events. Collaboration with the military and the private companies it contracts will assist scientists and managers with obtaining and developing software and data analysis tools. Collaborative proposals among scientists to receive larger pools of money for exploratory acoustic science will further develop the ability to correlate noise with ecological activities. The existing technologies and data analysis are adequate to meet resource managers' needs for vessel detection. However, collaboration is needed among resource managers to prepare large-scale programs that include centralized processing in an effort to address the lack of local capacity within management agencies to analyze and interpret the data. Workshop participants suggested that ACT might facilitate such collaborations through its website and by providing recommendations to key agencies and programs, such as DOD, NOAA, and I00s. There is a need to standardize data formats and archive acoustic environmental data at the national and international levels. Specifically, there is a need for local training and primers for public education, as well as by pilot demonstration projects, perhaps in conjunction with National Marine Sanctuaries. Passive acoustic technologies should be implemented immediately to address vessel monitoring needs. Ecological and health monitoring applications should be developed as vessel monitoring programs provide additional data and opportunities for more exploratory research. Passive acoustic monitoring should also be correlated with water quality monitoring to ease integration into long-term monitoring programs, such as the ocean observing systems. [PDF contains 52 pages]

(Report of the) Institute of Marine Biology and Oceanography, Fourah Bay College, University of Sierra Leone

Details are given of the Institute and its activities, in particular the research projects being undertaken. These include studies on the marine molluscs of Sierra Leone, the cockle fishery, a preliminary investigation on the fouling organisms affecting the raft-cultured oyster populations, larval oyster ecology in relation to oyster culture, preliminary studies on the reproductive cycle of the mangrove oyster (Crassostrea tulipa), and catch composition of fishes taken by beach-seines at Lumley (Freetown). Records of the west African manatee (Trichechus senegalensis) are noted.

Marine biology of the Sierra Leone River Estuary. 1. The physical environment

The Sierra Leone River Estuary is a relatively young drowned river valley, it is shallow except for a deep channel which passes close to the Freetown shoreline. The upper reaches merge into a network of creeks and channels fringed by large areas of mangrove swamps. It is a tidal estuary of the semi-mixed type with the saline oceanic water entering it on a diurnal cycle. The climate of Sierra Leone is marked by a very distinct change between a very wet rainy season and a dry season. The tidal range of the Estuary (spring 3.03m; neap 2.28m) does not impede normal use of the harbour. The tidal variations can be felt as far as 42 miles inland along the water courses of the Sierra Leone River and its tributaries. The volume of fresh water entering the Estuary is large during the rainy season and greatly reduced during the dry season. Consequently there is a marked fall in salinity during the rainy season and higher salinities due to the marine influence prevailing during the dry season. The nature of the shores and bottom, the hydrography and chemistry of the estuarine system have been outlined in relation to the prevailing climatic conditions.

Improved facilities for marine biology in East Africa

In 1967 the then University College of Dar es Salaam built a small laboratory on the shore at Kunduchi, 16 km from the main campus and 24 km north of Dar es Salaam. This was used for undergraduate field courses, and as a base for staff from the University to carry out research. It soon became apparent that the urgent need for studies of the marine environment in the East African area, and the lack of existing facilities, necessitated the development of the Kunduchi Marine Biology station into a research establishment with its own staff of full time scientists. This operation began in 1970: necessary structural modifications have been made to the building, staff have been recruited, and the station has been equipped with an adequate range of field and laboratory apparatus. A varied programme of research is now actively under way.

Elasmobranchs as living resources: Advances in the biology, ecology, systematics, and the status of the fisheries

This report owes its genesis to the foresight and enthusiam of Dr. Kazuhiro Mizue. By happy circumstance, Professor Mizue contacted me in 1983 with his visionary ideas on cooperative programs. He noted that the time was right because the Japan Society for the Promotion of Science and the National Science Foundation had mutually given priority to cooperative programs in marine biology. I therefore agreed to act as the U.S. coordinator and proposed to NSF, a short trip to Japan to negotiate site visits and timing with ten previously appointed Japanese scientists and, if that trip were successful, to negotiate a joint research project, possibly followed by a joint seminar. (PDF file contains 528 pages.)

Biology of the mullet species occurring in the estuaries of Freetown Peninsula

This brief paper gives some notes on the geographical distribution and salinity tolerances of some Mugil species occurring in the Black-Johnson estuary, Sierra Leone

Measures of turbidity in coastal waters, Coconut Island, Oahu, Hawaii, August 31 - September 2, 2005: workshop proceedings

A three day workshop on turbidity measurements was held at the Hawaii Institute of Marine Biology from August 3 1 to September 2, 2005. The workshop was attended by 30 participants from industry, coastal management agencies, and academic institutions. All groups recognized common issues regarding the definition of turbidity, limitations of consistent calibration, and the large variety of instrumentation that nominally measure "turbidity." The major recommendations, in order of importance for the coastal monitoring community are listed below: 1. The community of users in coastal ecosystems should tighten instrument design configurations to minimize inter-instrument variability, choosing a set of specifications that are best suited for coastal waters. The IS0 7027 design standard is not tight enough. Advice on these design criteria should be solicited through the ASTM as well as Federal and State regulatory agencies representing the majority of turbidity sensor end users. Parties interested in making turbidity measurements in coastal waters should develop design specifications for these water types rather than relying on design standards made for the analysis of drinking water. 2. The coastal observing groups should assemble a community database relating output of specific sensors to different environmental parameters, so that the entire community of users can benefit from shared information. This would include an unbiased, parallel study of different turbidity sensors, employing a variety of designs and configuration in the broadest range of coastal environments. 3. Turbidity should be used as a measure of relative change in water quality rather than an absolute measure of water quality. Thus, this is a recommendation for managers to develop their own local calibrations. See next recommendation. 4. If the end user specifically wants to use a turbidity sensor to measure a specific water quality parameter such as suspended particle concentration, then direct measurement of that water quality parameter is necessary to correlate with 'turbidity1 for a particular environment. These correlations, however, will be specific to the environment in which they are measured. This works because there are many environments in which water composition is relatively stable but varies in magnitude or concentration. (pdf contains 22 pages)

Report on the physical, bacteriological and biochemical analyses of seawater samples collected off existing sewage outfalls in the Sierra Leone River Estuary

The studies reported were undertaken as part of a wide environmental feasibility study for the establishment of a modern sewage system in Freetown. The aim of this part of the study was to determine whether the hydrological regime of the Sierra Leone River Estuary would permit the large-scale introduction of sewage into the estuary without damaging the environment. The important factors were whether: 1) there would be sufficient dilution of the sewage; 2) fleatable particles or other substances would create significant adverse effects in the estuarine ecosystem. The outfall sites are described together with the sampling stations, methods and analyses. Results include: 1) T/S profiles; 2) chemical analysis of the water. A review of literature on the Sierra Leone River Estuary is included which provides information on the plankton, benthos and fisheries. Results suggest that at certain points where local circulations occur it would be inadvisable to locate untreated sewage outfalls. Such points are frequently observed in small embayments. These studies have been of short duration but the data can serve as baseline for more extended investigations which would give a more complete picture of the seasonal patterns in the estuary.

Survey of the shrimp stocks of the Sierra Leone inshore shelf : a summary report outlining objectives, observations and recommendations on the status of the Sierra Leone shrimp fishery

This report gives the species and catch-rates per hour of some commercial shrimp species caught in the course of a short survey of inshore shelf fishing grounds. Species seen in significant quantities were: Parapenneopsis atlantica, Parapenaeus longirostris, Penaeus kerathurus and Penaeus duorarum notialis

Some data on landings of pelagic fish by the artisanal fishermen near Freetown during January-December 1978

Pelagic fish (except for tuna) are landed in Sierra Leone mainly by the artisanal fishermen. The two most important species are Sardinella and Ethmalosa.Deep-sea species are normally exploited by purse seiners of foreign countries. The landings of artisanal fishermen largely comprise Sardinella eba.Landing data for Sardinella landed at Tombo and Goderich, and for Ethmalosa at Tombo, are presented in tabular form. Collection methods are described, with a definition of the unit of fishing effort, and a description of the gear used.The landing data are discussed with particular attention to fishing effort, catch per unit effort, and price per ton