Proceedings of the International Workshop on age determination of oceanic pelagic fishes: Tunas, billfishes, and sharks, Miami, Florida, February 15-18,1982

Accurate and precise estimates of age and growth rates are essential parameters in understanding the population dynamics of fishes. Some of the more sophisticated stock assessment models, such as virtual population analysis, require age and growth information to partition catch data by age. Stock assessment efforts by regulatory agencies are usually directed at specific fisheries which are being heavily exploited and are suspected of being overfished. Interest in stock assessment of some of the oceanic pelagic fishes (tunas, billfishes, and sharks) has developed only over the last decade, during which exploitation has increased steadily in response to increases in worldwide demand for these resources. Traditionally, estimating the age of fishes has been done by enumerating growth bands on skeletal hardparts, through length frequency analysis, tag and recapture studies, and raising fish in enclosures. However, problems related to determining the age of some of the oceanic pelagic fishes are unique compared with other species. For example, sampling is difficult for these large, highly mobile fishes because of their size, extensive distributions throughout the world's oceans, and for some, such as the marlins, infrequent catches. In addition, movements of oceanic pelagic fishes often transect temperate as well as tropical oceans, making interpretation of growth bands on skeletal hardparts more difficult than with more sedentary temperate species. Many oceanic pelagics are also long-lived, attaining ages in excess of 30 yr, and more often than not, their life cycles do not lend themselves easily to artificial propagation and culture. These factors contribute to the difficulty of determining ages and are generally characteristic of this group-the tunas, billfishes, and sharks. Accordingly, the rapidly growing international concern in managing oceanic pelagic fishes, as well as unique difficulties in ageing these species, prompted us to hold this workshop. Our two major objectives for this workshop are to: I) Encourage the interchange of ideas on this subject, and 2) establish the "state of the art." A total of 65 scientists from 10 states in the continental United States and Hawaii, three provinces in Canada, France, Republic of Senegal, Spain, Mexico, Ivory Coast, and New South Wales (Australia) attended the workshop held at the Southeast Fisheries Center, Miami, Fla., 15-18 February 1982. Our first objective, encouraging the interchange of ideas, is well illustrated in the summaries of the Round Table Discussions and in the Glossary, which defines terms used in this volume. The majority of the workshop participants agreed that the lack of validation of age estimates and the means to accomplish the same are serious problems preventing advancements in assessing the age and growth of fishes, particularly oceanic pelagics. The alternatives relating to the validation problem were exhaustively reviewed during the Round Table Discussions and are a major highlight of this workshop. How well we accomplished our second objective, to establish the "state of the art" on age determination of oceanic pelagic fishes, will probably best be judged on the basis of these proceedings and whether future research efforts are directed at the problem areas we have identified. In order to produce high-quality papers, workshop participants served as referees for the manuscripts published in this volume. Several papers given orally at the workshop, and included in these proceedings, were summarized from full-length manuscripts, which have been submitted to or published in other scientific outlets-these papers are designated as SUMMARY PAPERS. In addition, the SUMMARY PAPER designation was also assigned to workshop papers that represented very preliminary or initial stages of research, cursory progress reports, papers that were data shy, or provide only brief reviews on general topics. Bilingual abstracts were included for all papers that required translation. We gratefully acknowledge the support of everyone involved in this workshop. Funding was provided by the Southeast Fisheries Center, and Jack C. Javech did the scientific illustrations appearing on the cover, between major sections, and in the Glossary. (PDF file contains 228 pages.)

Proceedings of the PICES/CoML/IPRC Workshop on Impact of Climate Variability on Observation and Prediction of Ecosystem and Biodiversity Changes in the North Pacific

Table of Contents [pdf, 0.09 Mb] Section I - Presentations and Discussions at Plenary Sessions Introduction and Overview of Workshop Objectives [pdf, 0.07 Mb] Plenary Session Presentations [pdf, 2.23 Mb] Reports of the Breakout Group Discussions [pdf, 0.43 Mb] Closing Plenary Discussion and Recommendations [pdf, 0.11 Mb] Section II - Extended Abstracts of Individual Presentations at Breakout Group Sessions Breakout Group 1: Physical/Chemical Oceanography and Climate [pdf, 6.14 Mb] Breakout Group 2: Phytoplankton, Zooplankton, Micronekton and Benthos [pdf, 28.14 Mb] Breakout Group 3: Fish, Squid, Crabs and Shrimps [pdf, 4.30 Mb] Breakout Group 4: Highly Migratory Fishes, Seabirds and Marine Mammals [pdf, 6.27 Mb] Appendix 1. Workshop agenda [pdf, 0.15 Mb] Appendix 2. List of participants [pdf, 0.13 Mb] (Document pdf contains 216 pages)

Southern California Baseline Studies and Analysis: 1975-1978. Master Table of Contents

This is only the table of contents for a series of technical reports done from 1975-1978. The papers were done on contract for BLM by a number of universities and consulting firms such as Science Applications, Inc., University of Southern California, Scripps Institute of Oceanography, Moss Landing Marine Laboratories, and various campuses of University of California and California State University. (PDF contains 36 pages)

Coastal brownfields and adaptation to climate change: Discussions on potential hazards from contaminated groundwater displacement due to saltwater incursion

Toxic-waste associated with coastal brownfield sites can pose serious risks to human and environmental health. In light of anticipated sea-level rise (SLR) due to global climate change, coastal brownfields require heightened attention. The primary intent of this study is to pose questions and encourage discussion of this problem among policy makers. Impacts from SLR on coastal zones are examined within a brownfield policy framework and, current coastal brownfield policy discussions with respect to SLR are also examined. (PDF contains 4 pages)

The dynamics of the fecundity of fishes, for example the roach, Rutilus rutilus (L.). [conclusions and figure/table captions only] [Translation from: Voprosy Ikhtiologii 3(1) 67-83, 1963]

The dynamics of the fecundity of roach, with emphasis on Rutilus rutilus (L.), were studied in waters in the European parts of the USSR. This translation provides conclusions, and figures and table captions only.

Synthesising co-management for Lake Victoria: discussions on models relating to concepts of sustainability and participative management

This book section aims to synthesise the results of the surveys related to the LVFRP by developing different strategies to implement a sustainable and participative co-management model.

A study of the reproductive biology of dace in the middle Ob [introduction , summary and table captions only] [Translation from: Trudy tomsk. gos. Univ. 125, pp.77-91]

The Siberian Dace (Leuciscus leuciscus baicalensis (Dyb)is an important trade fish in Siberian waters. In the Ob basin more than 30,000 centners are produced annually. Catches of dace fluctuate significantly both between different rivers and between years in the Tomsk region. Defining the stocks of dace in the waters of the Tomsk region and explaining the fluctuations over time seems to be a very important and relevant question for the workers of the fishing industry. An answer, however, requires an accurate knowledge of the biology of dace; its reproductive, feeding and migration habits and the conditions of wintering etc. In the following we examine one of the above questions i.e. the biology of the reproduction of dace. The study was carried out in the Middle Ob in May 1951. This tranlations provides the introduction, summary and table captions only of the original article.

From drawing board to dining table: the success story of the GIFT project

As compared to crops and livestock, the genetic enhancement of fish is in its infancy. While significant progress has been achieved in the genetic improvement of temperate fish such as salmonids, no efforts were made until the late 1980s for the genetic improvement of tropical finfish, which account for about 90 percent of global aquaculture production. This paper traces the history of the Genetic Improvement of Farmed Tilapia (GIFT) project initiated in 1988 by the WorldFish Center and its partners for the development of methods for genetic enhancement of tropical finfish using Nile tilapia (Oreochromis niloticus) as a test species. It also describes the impacts of the project on the adoption of these methods for other species and the dissemination of improved breeds in several countries in Asia and the Pacific.

Ghana coastal fisheries governance dialogue: Presentations, discussions and outcomes from a stakeholder forum on issues for reforming governance of Ghana’s coastal fisheries

This meeting, the second national Fisheries Governance Dialogue, aimed to help stakeholders in the fisheries sector generate a shared understanding of critical lessons and pathways for fisheries co-management success in Ghana. This was a direct response to the call from both fisheries communities and the government of Ghana for a radical change from the way fisheries resources are currently being managed. The meeting was attended by 60 men and women from stakeholder organizations and communities, and commenced with presentations on co-management experiences from local, regional and international participants. This was followed by panel discussions to extract lessons that specifically related to successfully implementing co-management in Ghana’s fisheries. Finally, breakout groups addressed in greater detail some issues of importance to fisheries governance reform in Ghana. While fisheries co-management is not a new concept in Ghana, participants heard that previous attempts to initiate these systems proved unsustainable. A number of lessons were drawn from these past experiences.

Holocene climate and El Nino history as recorded in the sediments of northern coastal Peru [abstract, table, and references]

EXTRACT (SEE PDF FOR FULL ABSTRACT): The history of the El Nino phenomena is recorded in both the fluvial and coastal sediments of northern Peru. The fluvial record was presented at the 1987 PACLIM Workshop and is discussed in detail elsewhere (Wells, 1987). However, the number of radiocarbon dated El Nino events has increased since Wells (1987) was published; this data is presented in Table 1.

Meteorological influences on North America quail populations [abstract, table, and figure]

EXTRACT (SEE PDF FOR FULL ABSTRACT): Comparative study of environmental influences on the population dynamics of three North American species of quail, California quail (Callipepla california), Gambel's quail (C. gambellii), and scaled quail (C. squamata) has lead to identification of differential sensitivity of these species to global weather patterns.

Reproduction, age and growth of the round scad Decapterus macrosoma Blecker 1851, Carangidae from Mozambique

Reproduction, age and growth of Decapterus macrosoma Blecker, 1851 were studied. The data were collected in Sofala Bank from commercial bottom trawlers and surveys. A total of 5,500 individuals were examined during the period 1979-1982. The species is caught in the same areas as D. russellii, but appears in lower quantities. Two main spawning periods a year, one in December-February and another one in June-September were found. Ageing was determined by counting daily growth rings in the otoliths. The parameters of von Bertalanffy's growth equation were L infinity=26 cm and K=0,6/year. Males and females seem to grow at the same rate.

Investigations on long distance transportation of fish. 5. Transportation of filleted and round seer fish (Scomberomorus sp.) from Kakinada to Calcutta by rail

Iced seer fish (Scomberomorus sp.) was transported by rail in expanded polystyrene insulated plywood boxes from Kakinada to Calcutta in round and fillet forms. While both withstood the rigors of transportation squarely, the fillets fetched only half the price of round fish in the auction conducted at the Calcutta market.

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.