Thursday, June 14, 2012

Fishing and the Environment

The Relative Importance of Fishing and the Environment
in the Regulation of Fish Population Abundance
June 26-28 2012



Thursday, May 10, 2012

Sustainable Yield in Fisheries

It is very difficult to achieve this goal. Typically, fisheries undergo stocks permanently at different temporal and spatial scales of exploitation that exceeds the biological capacity and ecological recovery of the species. On the other hand, the fishery always begins without further study of the population which will be exploted. When these studies exist, and these are more intensive, the population has already changed to another phase, ie, the response is delayed (Figure 1).

Figure 1. Evolution of changes in a fishery.

One factor that clearly shows these effects are average sizes of the populations subjected to exploitation. Body sizes of fish as well as the quality and quantity of their eggs, are subject to biological changes. Drastic natural events, and fishing pressure, can severely affect the exploited stocks (Figure 2). 
Figure 2. Some changes in a fish population during its inappropiate exploitation.
Generally, these changes can be observed after several years of inappropiate fishing pressure, but in some cases may occur over short periods due to a combination of several factors. Fisheries also have problems due to these changes, yields may decrease while the exploited population undergoes various changes (Figure 3). It is necessary to apply the ecosystem approach to fisheries management, through a comprehensive and multidisciplinary study taking in account all parts involved.

Wednesday, May 2, 2012

Wrong fisheries management decisions


In marine ecosystems there is an important connection between what happens in the surface layers of the sea and the dynamics of bottom-dwelling organisms. One of the key relationships identified for this relationship is called 'biological pump', which represents the exchange of matter and energy between the surface and bottom. 

On the other hand, it is important to consider that for many years has exerted strong pressure and human impact on the seabed and its ecological connections, one of those impacts identified is through the trawl fishery. This type of extractive activity removes most of the sediment surface and generates enormous disturbance on benthic communities at different scales of space.  Although in some parts of the world it is banned, this type of fishery is still practiced in some marine areas. This is critical particularly in countries with large fisheries associated with highly productive upwelling systems. The Peruvian marine ecosystem hosts a large population of fish (and other resources) of global economic importance, the main target species is the Peruvian anchovy, and therefore, its pelagic ecosystem has been a long time ago one of the most studied.  However, there are still some environmental aspects that have not been sufficiently addressed and that represent key issues for the comprehensive study and understanding of this ecosystem. It is also necessary to integrate this research in relation with the impact of the fishery on the Peruvian sea, which is generated at different scales of space and time.

Another major fisheries that also needs further research emphasis aims to Peruvian hake fishery (Merluccius gayi peruanus) This species has more than three decades of exploitation and the focus of study has pointed mainly to the study of the fishery, that is, fishing patterns, 'classical' population dynamics, among other issues arising from monitoring fishing only. However, this resource and other demersal species accompanying this vast habitat, have not undergone to thorough analysis on aspects of trophic ecology, community interactions, or determinations of its importance in the flow of matter and energy within the marine system.

Additionally, the northern coast of Peru, where is the hake fishery (Figure 1, mainly off Paita), is regularly affected by oceanographic fluctuations, especially the Cromwell Current, which conditions both biology and ecology of most organisms living in these waters.

 Figure 1.Port of Paita, Peru (click to enlarge)

This area also represents part of a biogeographical ecotone because it is an intersection point between the Panamanian province and the Peruvian province. However all this must be adequately protected for its continuity in time and their use by future generations. Special care should be given to trawling taking place in these marine areas. This method of fishing is, from a strictly scientific point of view, an inappropriate method for some marine populations and this should be strictly regulated. Although there is information, most people engaged in this fishery usually do not understand the consequences of their activity. On the contrary, it is common to ignore the recommendations of the scientists who warn of these dangers. This gets worse when there are misunderstandings about the fisheries data. One reason is the lack of criteria for fisheries ecology! When we limit the study of a exploited population to assess only fishing data, we have many problems, it is critical consider many other factors driving the patterns of distribution and concentration of marine resources. Conduct multidisciplinary approaches that allow more rigorous analysis, and conclusions more robust, is essential in fisheries management.

One of the most difficult things to do is "talk" to the fishery itself, and ensure that their members can understand the message. Understand the criteria and scientific decisions is one of the most difficult goals to achieve in fisheries management!  Normally, scientists are ridiculed because they simply do not say what industrial fishery want to hear (Figure 2); however, the fishery may be facing serious signals in exploited populations and their actual level of abundance and distribution, and be blind to this and still continue their activities and believe that everything stays the same or even better.  

 Figure 2. Perception of changes of fishing quotas (click to enlarge)
The misconception that the catch of some big fish in an exploited population of fish mean recovery of this population have long been demonstrated as misinterpretations of the real state of a fishery. Catch Per Unit Effort (CPUE) and the "false image" that gives this index about the real distribution and abundance (Figure 3) of the resource has also been observed in other cases such as the Atlantic cod fishery (Figure 4).

 Figure 3. Misinterpreting the reality of a fishery and its impact on fish stocks (click to enlarge).

 Figure 4. Collapse of Atlantic cod stock. (click to enlarge) Source: Millenium Ecosystems Assessment

Only considering an integrated management of our fisheries and being responsible with their full implementation and continuity, we get some 'sustainability' in exploited fish stocks...and remember to use the fisheries ecology please!

Thursday, March 1, 2012

International Conference on Fisheries and Aquatic Sciences

 
Get information here

1st Annual World Congress of Mariculture and Fisheries, Dalian, China

Further information here

142nd Annual meeting of the American Fisheries Society

Get information here

6th World Fisheries Congress, 2012

Get information here

Ecosystem Approach to Fisheries

Several perturbations (include the human impact) may alter significatively the structure of the ecosystem and how these components functioning over time.




Wednesday, January 25, 2012

Thursday, December 29, 2011

Effects of climate change on advective fluxes in high latitude regions, May, 2012

IMBER workshop sponsored by ESSAS and ICED on "Effects of climate change on advective fluxes in high latitude regions" (W4, 14 May 2012)

Convenors:
Ken Drinkwater (Institute of marine Research, Norway)
George Hunt (University of Washington, USA)
Eugene Murphy (British Antarctic Survey, UK)
Jinping Zhao (Ocean University of China, PR China)
This 1-day workshop will briefly review the advection of water masses within and between polar and sub-polar regions and their driving mechanisms. It will also review the role of advection on the ecology of these high latitude regions, including heat and nutrient fluxes as well as the advection of flora and fauna (Click here for more details about workshop's background). The major objective of the workshop, however, is to develop likely scenarios of these advective fluxes under climate change. Comparative studies of the responses in the Arctic and Antarctic regions are also of interest. To achieve these objectives we plan to bring together atmospheric scientists, climatologists, biogeochemists, physical and biological oceanographers, ecologists, and fisheries scientists who will use a combination of conceptual, statistical and numerical models studies. The workshop will also receive input from the ESSAS-sponsored Theme Session on “Arctic-Subarctic Interaction” to be held at the Ocean Sciences Meeting in Salt Lake City in February 2012 and the ICED Sentinel meeting on “Southern Ocean Ecosystem Change and Future Projections” to be held in Hobart in early May 2012. The workshop will consist of a few focused invited talks with significant discussion time to address the main topic, the expected future high latitude circulation patterns and their ecological effects.
The primary outcomes of the workshop aim to be:
  1. a paper on the future physical, chemical and biological fluxes in high latitude regions under climate change;
  2. identification of the gaps in our knowledge about these advective processes and development of recommendations for future research to address these gaps;
  3. discussions on the formation of a Working Group under IMBER to compare the structure and function of sub-polar and polar ecosystems for the Arctic and Antarctic.

Wednesday, December 21, 2011

World Oceans Summit, Cepella, Singapore

The world’s oceans are the setting for increasing economic activity and will continue to be so for years to come. Only in recent years have scientists begun to understand the significant impact of this growing industrialisation on the ecosystems of the seas and, by extension, on the broader biosphere we all inhabit. Now is the time to engage the global business community and change the nature of the debate...

Further information here

2012 Ocean Sciences Meeting, USA

2012 Ocean Sciences Meeting

20-24 February 2012
Salt Lake City · Utah · USA

This joint meeting is an international gathering of more than 4,000 attendees and is being sponsored by The Oceanography Society, the American Society of Limnology and Oceanography and the American Geophysical Union.


Further information here

Tuesday, December 13, 2011

Second International Symposium: Effects of Climate Change of the Word's Oceans

Second international symposium on "Effects of Climate Change on the World's Oceans" (co-sponsored by IMBER)
ESSAS and ICED workshop on "Effects of climate change on advective fluxes in high latitude regions" (W4, 14 May 2012)
Early registration and abstract submission deadline: 15 December 2011
More info...

Wednesday, November 30, 2011

POGO-SCOR Visiting Fellowships

This programme is jointly funded by POGO and the Scientific Committee on Oceanic Research (SCOR) and is designed to promote training and capacity building leading towards a global observation scheme for the oceans. The Programme has been a success for ten years, with a total of 125 fellowships awarded since 2001.  The fellowship program is open to scientists, technicians, graduate students (PhD) and post-doctoral fellows involved in oceanographic work at centres in developing countries and countries with economies in transition. Its main purpose is to advance sustained ocean observations and their applications.  Priority is given to applicants in early stages of career development. The fellowship is not intended for pure, "blue skies" research; it offers the opportunity to visit other oceanographic centres for a short period (1 to 3 months) for training on any aspect of oceanographic observations, analyses, and interpretation.

The Selection Criteria involve a number of factors including:
  1. Quality of the application;
  2. Relevance of the application to the priority areas identified in the Fellowship Announcement (Argo Floats; Fixed-Point Time-Series Observations; Large-scale, Operational Biological Observations including Biodiversity; Emerging Technologies for Ocean Observations; Data management; Coastal observations/ Coastal Zone Management; Ocean and coastal modelling)
  3. Evidence that the training will lead to capacity-building with potential lasting impact on regional observations; and,
  4. The need to maximise regional distribution of the awards....

    More information here

POGO Visiting Professorship Programme

Introduction

In collaboration with the Nippon foundation, POGO established the NF-POGO Visiting Professorship Programme, which ran for 3 years (2004-2007). This initiative metamorphosed into the Centre of Excellence Programme, which allows scholars from developing countries to receive training from world-class scientists for ten months at the Bermuda Institute of Ocean Sciences.

POGO continues to run a Visiting Professorship programme, which generally funds one Professor every year. The Professorship allows short visits (2 weeks to 3 months) of distinguished scientists from advanced oceanographic institutes to institutes in developing countries and economies in transition, to provide training and mentoring, to develop collaborations and enhance networking. Follow this link to read about past POGO Visiting Professorships.

The goal of the visiting professorship is capacity building in the host institution, leading to enhanced sustained ocean observations to address societal issues of the day. Development of highly-trained scientific professionals is the priority. Promoting contacts, collaborations and networking among institutions of developing and developed countries is another goal.

This programme is seen as a complement to the POGO-SCOR Visiting Fellowship Programme.

More information here

Friday, October 21, 2011

Oceanology International 2012, London

Call for Papers

Oceanology International is the global forum where industry, academia and government share knowledge and connect with marine technology and ocean science, improving their strategies for measuring, exploiting, protecting and operating in the world's oceans. As the premier event of its type, Oceanology International attracts more engineers, technical specialists and senior industry figures than any other marine science and ocean technology event in the world.
 
The conference will comprise 6 one day sessions running throughout the event (two per day) 
 
Conference Chairman: Professor Ralph Rayner
 
Session Chairs:
Marine Survey: Andy Hill, BP
Maritime Security: Rob Balloch, Sonardyne
Navigation and Positioning: Ed Danson, C & C Technologies
Ocean Observation and Forecasting: Zdenka Willis, NOAA
Oil and Gas: Colin Grant, BP
 
Offshore Renewables session is organised in association with Renewables UK 
 
Absracts are invited on the following topic areas:
 
 
More information here

Explanation for glowing seas suggested

Proposed bioluminescence mechanism: When a dinoflagellate is mechanically agitated, an electrical impulse travels around its vacuole membrane. This impulse opens up proton channels that allow protons to flow from the vacuole into the scintillons, where they activate light-emitting luciferase proteins. The result: A flash of light. Credit: Zina Deretsky, National Science Foundation
It has long been known that distinctive blue flashes -- a type of bioluminescence -- that are visible at night in some marine environments are caused by tiny, unicellular plankton known as dinoflagellates. However, a new study has, for the first time, detailed the potential mechanism for this bioluminesence.

The study, which was partially funded by the National Science Foundation, is reported by Susan Smith of Emery School of Medicine, Thomas DeCoursey of Harvard University and colleagues in the Oct. 17, 2011 issue of the (PNAS).
A key aspect of the potential mechanism for in dinoflagellates proposed in the PNAS study involves voltage-gated proton channels--channels in membranes that can be opened or closed by chemical or electrical events.
J. Woodland Hastings, a member of the Smith and DeCoursey research team and an author of the PNAS article, suggested the presence of voltage-gated proton channels in dinoflagellates almost forty years ago. But the Smith and Decoursey team only recently confirmed them by the identification and subsequent testing of dinoflagellate genes that are similar to genes for voltage-gated proton channels that had previously been identified in humans, mice and .
According to the study, here is how the light-generating process in dinoflagellates may work: As dinoflagellates float, generated by the movement of surrounding water sends around an internal compartment within the organism, called a vacuole--which holds an abundance of protons. (See accompanying illustration.) These electrical impulses open so-called voltage-sensitive proton channels that connect the vacuole to tiny pockets dotting the vacuole membrane, known as scintillons.
Once opened, the voltage-sensitive proton channels may funnel protons from the vacuole into the scintillons. entering the scintillons then activate luciferase--a protein, which produces flashes of light, that is stored in scintillons. Flashes of light produced by resulting luciferase activation would be most visible during blooms of dinoflagellates.
This research illuminates the novel mechanisms underlying a beautiful natural phenomenon in our oceans, and enhances our understanding of dinoflagellates--some of which can produce toxins that are harmful to the environment.
Provided by National Science Foundation (news : web)
 

No simultaneous warming of Northern and Southern hemispheres as a result of climate change for 20,000 years

Svante Björck's study thus goes 14 000 years further back in time than previous studies have done.
"What is happening today is unique from a historical geological perspective", he says.
Svante Björck has gone through the global climate archives, which are presented in a large number of research publications, and looked for evidence that any of the climate events that have occurred since the end of the last Ice Age 20 000 years ago could have generated similar effects on both the northern and southern hemispheres simultaneously.
It has not, however, been possible to verify this. Instead, he has found that when, for example, the temperature rises in one hemisphere, it falls or remains unchanged in the other.
"My study shows that, apart from the larger-scale developments, such as the general change into warm periods and ice ages, climate change has previously only produced similar effects on local or regional level", says Svante Björck.
As an example, let us take the last clear , which took place between the years 1600 and 1900 and which many know as the Little Ice Age. Europe experienced some of its coldest centuries. While the extreme cold had serious consequences for agriculture, state economies and transport in the north, there is no evidence of corresponding simultaneous temperature changes and effects in the southern hemisphere.
The climate archives, in the form of core samples taken from marine and lake sediments and glacier ice, serve as a record of how temperature, precipitation and concentration of atmospheric gases and particles have varied over the course of history, and are full of similar examples.
Instead it is during 'calmer' climatic periods, when the climate system is influenced by external processes, that the researchers can see that the climate signals in the archives show similar trends in both the northern and southern hemispheres.
"This could be, for example, at the time of a meteorite crash, when an asteroid hits the earth or after a violent volcanic eruption when ash is spread across the globe. In these cases we can see similar effects around the world simultaneously", says Svante Björck.
Professor Björck draws parallels to today's situation. The levels of greenhouse gases in the atmosphere are currently changing very rapidly. At the same time, global warming is occurring.
"As long as we don't find any evidence for earlier changes leading to similar simultaneous effects on a global scale, we must see today's as an exception caused by human influence on the earth's carbon cycle", says Svante Björck, continuing:
"this is a good example of how geological knowledge can be used to understand our world. It offers perspectives on how the earth functions without our direct influence and thus how and to what extent human activity affects the system."
Svante Björck's results were published this summer in the scientific journal Climate Research.
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