The BACOMA cod-end. History and recent developments in BACOMA cod-end regulations and a proposal for abetter specification of the BACOMA cod-end for Baltic Sea cod fishery

To improve the cod stocks in the Baltic Sea, a number of regulations have recently been established by the International Baltic Sea Fisheries Commission (IBSFC) and the European Commission. According to these, fishermen are obliged to use nets with escape windows (BACOMA nets) with a mesh size of the escape window of 120 mm until end of September 2003. These nets however, retain only fish much larger than the legal minimum landing size would al-low. Due to the present stock structure only few of such large fish are however existent. As a consequence fishermen use a legal alternative net. This is a conventional trawl with a cod-end of 130 mm diamond-shaped meshes (IBSFC-rules of 1st April 2002), to be increased to 140 mm on 1st September 2003, according to the mentioned IBSFC-rule. Due legal alterations of the net by the fishermen (e.g. use of extra stiff net material) these nets have acquired extremely low selective properties, i. e. they catch very small fish and produce great amounts of discards. Due to the increase of the minimum landing size from 35 to 38 cm for cod in the Baltic, the amount of discards has even increased since the beginning of 2003. Experiments have now been carried out with the BACOMAnet on German and Swedish commercial and research vessels since arguments were brought forward that the BACOMA net was not yet sufficiently tested on commercial vessels. The results of all experiments conducted so far, are compiled and evaluated here. As a result of the Swedish, Danish and German initiative and research the European Commission reacted upon this in June 2003 and rejected the increase of the diamond-meshed non-BACOMA net from 130 mm to 140mm in September 2003. To protect the cod stocks in the Baltic Sea more effectively the use of traditional diamond meshed cod-ends with-out escape window are prohibited in community waters without derogation, becoming effective 1st of September 2003. To enable more effective and simplified control of the bottom trawl fishery in the Baltic Sea the principle of a ”One-Net-Rule“ is enforced. This is going to be the BACOMA net, with the meshes of the escape window being 110 mm for the time being. The description of the BACOMA net as given in the IBSFC-rules no.10 (revision of the 28th session, Berlin 2002) concentrates on the cod-end and the escape window but only to a less extent on the design and mesh-composition of the remaining parts of the net, such as belly and funnel and many details. Thus, the present description is not complete and leaves, according to fishermen, ample opportunity for manipulation. An initiative has been started in Germany with joint effort from scientists and the fishery to better describe the entire net and to produce a proposal for a more comprehensive description, leaving less space for manipulation. A proposal in this direction is given here and shall be seen as a starting point for a discussion and development towards an internationally uniform net, which is agreed amongst the fishery, scientists and politicians. The Baltic Sea fishery is invited to comment on this proposal, and recommendations for further improvement and specifications are welcomed. Once the design is agreed by the Baltic Fishermen Association, it shall be proposed to the IBSFC and European Commission via the Baltic Fishermen Association.

Reconstructing an 83-Year Time Series of Daily Sea Surface Temperature at Pacific Grove, California

Daily sea surface temperatures have been acquired at the Hopkins Marine Station in Pacific Grove, California since January 20, 1919.This time series is one of the longest oceanographic records along the U.S. west coast. Because of its length it is well-suited for studying climate-related and oceanic variability on interannual, decadal, and interdecadal time scales. The record, however, is not homogeneous, has numerous gaps, contains possible outliers, and the observations were not always collected at the same time each day. Because of these problems we have undertaken the task of reconstructing this long and unique series. We describe the steps that were taken and the methods that were used in this reconstruction. Although the methods employed are basic, we believe that they are consistent with the quality of the data. The reconstructed record has values at every time point, original, or estimated, and has been adjusted for time-of-day variations where this information was available. Possible outliers have also been examined and replaced where their credibility could not be established. Many of the studies that have employed the Hopkins time series have not discussed the issue of data quality and how these problems were addressed. Because of growing interest in this record, it is important that a single, well-documented version be adopted, so that the results of future analyses can be directly compared. Although additional work may be done to further improve the quality of this record, it is now available via the internet. [PDF contains 48 pages]

Green Guide to the Cayman Islands 2: Climate change and the sea around us

This Green Guide provides a brief summary of the alarming evidence of changing climate in the Cayman Islands. As we illustrated in our first Green Guide (2008), our lives on these three magical islands are intimately connected to the land and the surrounding sea. Our economy depends on keeping our islands healthy, because our coral reefs, our beaches, our natural heritage, all draw many thousands of overseas visitors to our shores. It is our responsibility, as stakeholders sharing this beautiful environment, to do what we can to minimise our impact upon it... [PDF contains 32 pages]

Bestandserfassung und -überwachung des atlanto-skandischen Herings. EU-Studie "Hydroacoustic Surveys of Atlanto-Scandian Herring in the Norwegian Sea, 1998-2000 (ASH-II)"

The atlanto-scandian herring consists of two major stocks, i.e. the Icelandic summer spawner and the Norwegian spring spawner. Both stocks have recovered well after complete collapse in the seventies and allow for a controlled fishery. The total allowable catch of the Norwegian spring spawner is currently 1.3 mill. t. The resumption of the fishery is accompanied by an annual and multi-national survey with Norwegian, Faeroe Islands, Icelandic and Russian contribution. In 1998 the EU will contribute to the survey with the Swedish vessel ”Argos” and in 1999 with the ”Walther Herwig III” under Dutch, Swedish and German participation. About half of the survey costs are covered by the EU by means of a funded study, the other half is contributed by the participating nations.

Detailed experimental iced-storage characteristics of Barents Sea cod (Gadus morhua)

Im August 1997 wurde an Bord des FFS „Walther Herwig“ ein Eislagerversuch mit Kabeljau aus der Barebtssee durchgeführt. Die Fische wurden in täglichem Abstand auf ihre chemischen, physikalischen, sensorischen und mikrobiologischen Eigenschaften hin untersucht. Die analytischen Daten wurden jeweils mit den Tagen in Eis korreliert. Es erwies sich, daß die Werte vom Fischtester VI sowie RT Frischetester, von Dimethylamin- und Trimethylaminoxidstickstoff, die Qualitätseinstufung anhand des EUQualitätsbewertungsschemas, die sensorische Bewertung von gegarten Filetproben und die Gesamtkeimzahl auf der Haut am besten mit den im Eis verbrachten Tagen korrelierten. Die guteKorrelation zwischen sensorischen und instrumentell ermittelten Daten läßt in gewissem Umfang einen Ersatz von Sensorikdaten durch instrumentell ermittelten zu.

Die Ostsee-Fischereikommission setzt stärker auf biologische Vorsorge. Ergebnisse der Internationalen Ostsee-Fischereikommission (International Baltic Sea Fishery Commission - IBSFC) vom 7. bis 11. September 1998 in Warschau

Die Tagung setzte den während der vorigen Jahrestagung zu beobachtenden Kurs einer Schwerpunktverlagerung generell fort. Diese ist durch die stärkere Berücksichtigung des Vorsorgeansatzes im Fischereimanagement auf der Grundlage wissenschaftlicher Empfehlungen des ACFM (Management-Komitee für Fischerei) des ICES gekennzeichnet. Damit traten die in der Vergangenheit fischereipolitisch dominierten nationalen Managementinteressen weitestgehend in den Hintergrund und trugen somit zu einer sachlichen Tagungsatmosphäre bei. Wichtigste Tagungsthemen waren die Ausnutzung der nationalen Quoten für 1997 und 1998 (1. Halbjahr), die Festlegung der zulässigen Gesamtfangmengen (TAC) für die internationalen Fischereien 1999, aber auch Strategien zur Nutzung der lebenden Ressourcen der Ostsee unter den Bedingungen des Vorsorgeansatzes im Fischereimanagement. An den Beratungen nahmen Ländervertreter und Experten Estlands, der EU, Lettlands, Polens und der Russischen Föderation sowie Beobachter des ICES (Internationaler Rat für Meeresforschung) und der HELCOM (Helsinki-Kommission) teil.

Sea-level rise in Hawaii: Implications for future shoreline locations and Hawaii coastal management

Management of coastal development in Hawaii is based on the location of the certified shoreline, which is representative of the upper limit of marine inundation within the last several years. Though the certified shoreline location is significantly more variable than long-term erosion indicators, its migration will still follow the coastline's general trend. The long-term migration of Hawaii’s coasts will be significantly controlled by rising sea level. However, land use decisions adjacent to the shoreline and the shape and nature of the nearshore environment are also important controls to coastal migration. Though each of the islands has experienced local sea-level rise over the course of the last century, there are still locations across the islands of Kauai, Oahu, and Maui, which show long- term accretion or anomalously high erosion rates relative to their regions. As a result, engineering rules of thumb such as the Brunn rule do not always predict coastal migration and beach profile equilibrium in Hawaii. With coastlines facing all points of the compass rose, anthropogenic alteration of the coasts, complex coastal environments such as coral reefs, and the limited capacity to predict coastal change, Hawaii will require a more robust suite of proactive coastal management policies to weather future changes to its coastline. Continuing to use the current certified shoreline, adopting more stringent coastal setback rules similar to Kauai County, adding realistic sea-level rise components for all types of coastal planning, and developing regional beach management plans are some of the recommended adaptation strategies for Hawaii. (PDF contains 4 pages)

Building a sustainable community of coastal leaders to deal with sea level rise and inundation

Sea level rise and inundation were stated to be the highest priorities in the community-developed Ocean Research Priorities Plan and Implementation Strategy in 2005. Although they remain stated priorities, very few resources have been allocated towards this challenge. Inundation poses a substantial risk to many coastal communities, and the risk is projected to increase because of continued development, changes in the frequency and intensity of inundation events, and acceleration in the rate of sea-level rise along our vulnerable shorelines. (PDF contains 4 pages) There is an increasing urgency for federal and state governments to focus on the local and regional levels and consistently provide the information, tools, and methods necessary for adaptation. Calls for action at all levels acknowledge that a viable response must engage federal, state and local expertise, perspectives, and resources in a coordinated and collaborative effort. A workshop held in December 2000 on coastal inundation and sea level rise proposes a shared framework that can help guide where investments should be made to enable states and local governments to assess impacts and initiate adaptation strategies over the next decade.

Enforcement of associated protected measures in particularly sensitive sea areas

The distinguished character of Particularly Sensitive Sea Areas (PSSAs) is that every application for PSSAs must be accompanied by Associated Protected Measures (APMs) which can make PSSAs efficient in practice.1 That is why APMs are regarded as the core feature of every PSSA.2 APM is “an international rule or standard that falls within the purview of an international maritime organization (IMO) and regulates international maritime activities for the protection of the area at risk.” So far, APMs have been approved by IMO as following: -Compulsory or recommended pilotage -Mandatory ship reporting -An area to be avoided -Traffic separation schemes -Discharge prohibition or regulations -Mandatory no anchoring areas -Deep water routes -Emission control areas (PDF contains 5 pages)

Looking for safe harbor in a crowded sea: Coastal space use conflict and marine renewable energy development

Technological advances in the marine renewable energy industry and increased clarity about the leasing and licensing process are fostering development proposals in both state and federal waters. The ocean is becoming more industrialized and competition among all marine space users is developing (Buck et al. 2004). More spatial competition can lead to conflict between ocean users themselves, and to tensions that spill over to include other stakeholders and the general public (McGrath 2004). Such conflict can wind up in litigation, which is costly and takes agency time and financial resources away from other priorities. As proposals for marine renewable energy developments are evaluated, too often decision-makers lack the tools and information to properly account for the cumulative effects and the tradeoffs associated with alternative human uses of the ocean. This paper highlights the nature of marine space conflicts associated with marine renewable energy literature highlights key issues for the growth of the marine renewable energy sector in the United States. (PDF contains 4 pages)

Improving reporting of uncertainties in sea level rise assessments

Sea level rise (SLR) assessments are commonly used to identify the extent that coastal populations are at risk to flooding. However, the data and assumptions used to develop these assessments contain numerous sources and types of uncertainty, which limit confidence in the accuracy of modeled results. This study illustrates how the intersection of uncertainty in digital elevation models (DEMs) and SLR lead to a wide range of modeled outcomes. SLR assessments are then reviewed to identify the extent that uncertainty is documented in peer-reviewed articles. The paper concludes by discussing priorities needed to further understand SLR impacts. (PDF contains 4 pages)

Predicting the effects of climate change on sea turtle nesting habitat in Florida

Rising global temperatures threaten the survival of many plant and animal species. Having already risen at an unprecedented rate in the past century, temperatures are predicted to rise between 0.3 and 7.5C in North America over the next 100 years (Hawkes et al. 2007). Studies have documented the effects of climate warming on phenology (timing of seasonal activities), with observations of early arrival at breeding grounds, earlier ends to the reproductive season, and delayed autumnal migrations (Pike et al. 2006). In addition, for species not suited to the physiological demands of cold winter temperatures, increasing temperatures could shift tolerable habitats to higher latitudes (Hawkes et al. 2007). More directly, climate warming will impact thermally sensitive species like sea turtles, who exhibit temperature-dependent sexual determination. Temperatures in the middle third of the incubation period determine the sex of sea turtle offspring, with higher temperatures resulting in a greater abundance of female offspring. Consequently, increasing temperatures from climate warming would drastically change the offspring sex ratio (Hawkes et al. 2007). Of the seven extant species of sea turtles, three (leatherback, Kemp’s ridley, and hawksbill) are critically endangered, two (olive ridley and green) are endangered, and one (loggerhead) is threatened. Considering the predicted scenarios of climate warming and the already tenuous status of sea turtle populations, it is essential that efforts are made to understand how increasing temperatures may affect sea turtle populations and how these species might adapt in the face of such changes. In this analysis, I seek to identify the impact of changing climate conditions over the next 50 years on the availability of sea turtle nesting habitat in Florida given predicted changes in temperature and precipitation. I predict that future conditions in Florida will be less suitable for sea turtle nesting during the historic nesting season. This may imply that sea turtles will nest at a different time of year, in more northern latitudes, to a lesser extent, or possibly not at all. It seems likely that changes in temperature and precipitation patterns will alter the distribution of sea turtle nesting locations worldwide, provided that beaches where the conditions are suitable for nesting still exist. Hijmans and Graham (2006) evaluate a range of climate envelope models in terms of their ability to predict species distributions under climate change scenarios. Their results suggested that the choice of species distribution model is dependent on the specifics of each individual study. Fuller et al. (2008) used a maximum entropy approach to model the potential distribution of 11 species in the Arctic Coastal Plain of Alaska under a series of projected climate scenarios. Recently, Pike (in press) developed Maxent models to investigate the impacts of climate change on green sea turtle nest distribution and timing. In each of these studies, a set of environmental predictor variables (including climate variables), for which ‘current’ conditions are available and ‘future’ conditions have been projected, is used in conjunction with species occurrence data to map potential species distribution under the projected conditions. In this study, I will take a similar approach in mapping the potential sea turtle nesting habitat in Florida by developing a Maxent model based on environmental and climate data and projecting the model for future climate data. (PDF contains 5 pages)

Coastal plant growth and CO2 enrichment: Can the productivity of black needle rush keep pace with sea level rise?

The rate of sea level change has varied considerably over geological time, with rapid increases (0.25 cm yr-1) at the end of the last ice age to more modest increases over the last 4,000 years (0.04 cm yr-1; Hendry 1993). Due to anthropogenic contributions to climate change, however, the rate of sea level rise is expected to increase between 0.10 and 0.25 cm year-1 for many coastal areas (Warrick et al. 1996). Notwithstanding, it has been predicted that over the next 100 years, sea levels along the northeastern coast of North Carolina may increase by an astonishing 0.8 m (0.8 cm yr-1); through a combination of sea-level rise and coastal subsidence (Titus and Richman 2001; Parham et al. 2006). As North Carolina ranks third in the United States with land at or just above sea level, any additional sea rise may promote further deterioration of vital coastal wetland systems. (PDF contains 4 pages)

Rents drain in fishery: the case of Lake Victoria Nile Perch fishery

Many fisheries are potentially very valuable. According to a recent report by the World Bank and the FAO (2008), global fisheries rents could be as high as US$ 40-60 billion annually on a sustainable basis. However, according to the report, due to the “common property problem”, most fisheries of the world are severely overexploited and generate no economic rents. The Lake Victoria Nile perch fishery could be among the most valuable fisheries in the world. Unfortunately, also this fishery has fallen prey to the common property problem with excessive fishing effort, dwindling stocks and declining profitability. As a result, there is a large and growing rents loss in this fishery (compared to the optimal) reducing economic welfare and economic growth opportunities in the countries sharing this fishery. As in other fisheries, the biological and economic recovery of this fishery can only come though improved fisheries management

Managing Nile perch using slot size: is it possible?

The fishery of Lake Victoria became a major commercial fishery with the introduction of Nile perch in 1950s and 1960s. Biological and population characteristics point to a fishery under intense fishing pressure attributed to increased capacity and use of illegal fishing gears. Studies conducted between 1998 to 2000 suggested capture of fish between slot size of 50 to 85 cm TL to sustain the fishery. Samples from Kenya and Uganda factories in 2008 showed that 50% and 71% of individuals processed were below the slot size respectively. This study revealed that fish below and above the slot has continued being caught and processed. This confirms that the slot size is hardly adhered to by both the fishers and the processors. The paper explores why the slot size has not been a successful tool in management of Nile perch and suggests strategies to sustain the fishery