• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Mariculture. Natural cod stocks going down. There has been much press coverage of the decline in natural cod stocks due to over fishing in the North Sea.

Extracts from this document...

Introduction

Fish- Beneath the Surface (An article for 'Future of Fish' magazine) Natural cod stocks going down. There has been much press coverage of the decline in natural cod stocks due to over fishing in the North Sea. I like my cod and chips and so was quite concerned about this. It may be too late to get the numbers back up to 1970's levels but less documented by the press, is the rapid growth of mariculture, the cultivation of marine organisms for food, which retailers say could 'revolutionise the fishing industry' (2). I visited the Manx Mariculture fish hatchery to investigate the principles behind fish farming and soon discovered that it was not without its problems. As my guide, Rick Fullerton, explained, a bacterial problem in the live feed meant that the hatchery faced a crisis in the year 2006 when only a few hundred cod were produced instead of the target 1 million. This is a common problem in mariculture and there is the potential for exciting new developments in the production of live feed which could eliminate this problem in the future. Use of live feed as an answer In order to kill bacteria, live feed may be disinfected or treated with UV rays (6). ...read more.

Middle

This is most likely because there is limited availability of carbohydrates in marine environments (9). If the diet does not provide enough energy, protein needed for growth will be broken down instead which increases the costs of fish farming. Protein is needed in the diet as it provides the 10 essential amino acids which the fish cannot synthesis. Fishmeal also contains minerals such as calcium, phosphorus and magnesium and vitamins including the B-complex (8). There are, however, ethical concerns over the use of fishmeal as some argue that for every tonne of farmed fish produced, 5 tonnes of fishmeal are used in the process. On the other hand, fishmeal can be seen to reduce pollution to the environment as there is increased nutrient uptake by the fish (8). Green issues Further environmental concerns which surround fish farming include the pollution caused by waste being discharged into the sea. However, made up of fish waste and undigested food, this is natural and it does not cause major problems or damage to marine environments (3). This likely to be accurate and precise information as Nick Fullerton is a professional with a degree in biology and has had many years experience in mariculture. The energy cost of running the hatchery which includes pumping water 24 hours day and the continuous monitoring probes must also be taken into account when considering the environmental implications of fish farming. ...read more.

Conclusion

http://aquanic.org/publicat/state/il-in/as-503.htm [Accessed 14 March 2007]. (11) Leonard N, Blancheton J. P., Guiraud J. P. (2000) Populations of heterotrophic bacteria in an experimental recirculating aquaculture system. Aquacultural engineering, 22(1-2), 109-120 (12) Wikipedia (2007) Environmental sciences. http://en.wikipedia.org/wiki/Dissolved_oxygen [Accessed 13 March 2007]. (13) Hayward G (1992) Applied Ecology. London: Thomas Nelson & Sons Ltd (14) Convention on Biological Diversity (2007) Jakarta Mandate Marine and Coastal Biodiversity - Mariculture. http://www.biodiv.org/programmes/areas/marine/mariculture.aspx. [Accessed 13 March 2007]. (15) Whipple A B C (1983) Restless oceans. USA: Time-Life Books Commentary 1. Biological methods and processes used. The problem of decrease in cod stocks together with difficulties with contamination of feed for 'mariculture' is outlined well (4). There is then a very good discussion of different types of live feed as answer to the problem of contamination (4). In addition some data is given to show just how effective live feed is but perhaps more of this data and evidence could have been provided as part of the discussion (3) (11 marks) 2. Applications and implications of the biology encountered There is a good discussion of the environmental and ethical implications of mariculture (4). In addition, the economics of live feed is looked at as a limitation (4). This is then followed by a discussion of the advantages of weaning the fish off live feed and converting to a diet of hard fishmeal pellets. Plenty of data and examples are given here (4). (12 marks) 3. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our AS and A Level Energy, Respiration & the Environment section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related AS and A Level Energy, Respiration & the Environment essays

  1. Marked by a teacher

    Effect of nitrate concentration on the growth of Duckweeds

    5 star(s)

    meant that enough water entered the root cells and generated the uptake of both the macro and micro nutrients needed for growth. This is why all the fronds in both the concentrations were dark healthy green coloured, as they were rich in water and all nutrients.

  2. Marked by a teacher

    Home Economics - Why is nutrition important to sports people?

    5 star(s)

    Regular checks of iron status are recommended. Rowers should include high sources of iron in the diet on a regular basis. Advice from a sports dietician should be sought if a low iron status develops. Fluid Needs Long training sessions on the water lead to significant sweat losses, particularly when undertaken twice a day.

  1. Field trip report Mangrove ecosystem

    If the ground increases in height from the 0-10m positions, record the difference as '+'; if the ground decreases in height, record the difference as '-'. For simplicity, the set-up employed in the surveying is shown below: 3. At 0m, 10m, 20m, 30m, 40m point of the transect line: a.

  2. Investigate the effect of bile salt concentration on the digestion of milk by the ...

    If the reactants are kept in the water bath their temperature will remain constant and so this eliminates the problem of reheating if the temperature of the reactants has dropped. Reliability of results The reliability of the experiment was improved due to the use of a data logger to accurately record the change in pH instead of using an indicator.

  1. Aspects of the Ecology of the Shingle beach at Greatstone

    salt and temperature levels DOG WHELKS AND BARNACLES Chi-Squared field data Copt Point 01.07.10. Introduction: We studied the middle shore of a beach at low tide, it was densely populated with rock. We studied the rock for dog whelks and barnacles to see if there was a relationship between the two species.

  2. Moscow, Russian Federation Summer-time pollution and summer smog problems

    Classification of summer smog pollutants Table 1. Maximum Permissible Concentrations/Values in mg/m3 (Russian Federation) (Mosecomonitoring 2010). Classification of hazard system is based on 4 classes, where 1 is the most hazardous and 4 is the least hazardous substance (Mosecomonitoring 2010).

  1. Weed study. Dandelions - descrption and characteristics. Investigation to dandelion distribution.

    So I collect my results in a systematic way. > Spoon - this was used to dig out the soil samples. Was very useful. However, was not accurate. I may have got some more or less soil, in each pot.

  2. Malaria Issue Report

    By 2010 the proportion of mosquitoes resistant to Deltamethrin was 37%.[11] Testing Malaria parasites in the blood can best be detected under a microscope, but, when this is not available malaria cases can also be quickly and accurately identified using a Rapid Diagnostic Test (RDT).

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work