Objective
The project aims to develop an integrated survey system of work based on improved hydroacoustic measurement methods and techniques which will reduce, as far as possible, all important sources of bias to be entered in the results of acoustic surveys. Therefore the accuracy and utility of the calculated biomass estimates of the target species will be considerably increased.
The measurement methods and techniques applied in hydroacoustic surveys may give considerable bias either in the negative or the positive direction in the results of calculated absolute biomass estimates of the target species of small pelagic fish. The development of an integrated survey system of work is underway which is based on improved hydroacoustic measurement methods and techniques which will reduce, as much as possible, important sources of bias to be entered in the results of acoustic surveys. Therefore, the accuracy and utility of the calculated biomass estimates of the target species will be considerably increased. Target strength (TS) measurements were performed during standard acoustic surveys and in experiments conducted on control populations confined at different fish densities in cages. Aim of the above measurements was to study the effect of diurnal changes in TS of the target populations and find out the relationships between the TS in situ and that under control conditions.
The measurement methods and techniques applied in hydroacoustic surveys may give considerable bias either in the negative (underestimation) or positive (overestimation) direction in the results of calculated absolute biomass estimates of the target species of small pelagic fish. A number of sources bias can be readily identified: uncertainties concerning species identification based on echo traces of mixed aggregations; very variable backscattering coefficients even within species and within similar fish concentrations; and inefficiency of fishing samples to provide reliable estimates of fish length distributions of target species and species composition of the target biomass. The most striking feature of biased acoustic estimates is their large variability in space and time. It is very difficult to assess whether observed differences of biomass estimations in space and time are real differences which are governed by natural factors such as changes in fish behaviour patterns, seasonal immigration and emigr tion, and fluctuations in the size of the resources, or are differences which are attributed to consistent errors in measurements which give rise to biases.
Fields of science (EuroSciVoc)
CORDIS classifies projects with EuroSciVoc, a multilingual taxonomy of fields of science, through a semi-automatic process based on NLP techniques. See: The European Science Vocabulary.
CORDIS classifies projects with EuroSciVoc, a multilingual taxonomy of fields of science, through a semi-automatic process based on NLP techniques. See: The European Science Vocabulary.
- agricultural sciences agriculture, forestry, and fisheries fisheries
- social sciences sociology demography human migrations
You need to log in or register to use this function
We are sorry... an unexpected error occurred during execution.
You need to be authenticated. Your session might have expired.
Thank you for your feedback. You will soon receive an email to confirm the submission. If you have selected to be notified about the reporting status, you will also be contacted when the reporting status will change.
Programme(s)
Multi-annual funding programmes that define the EU’s priorities for research and innovation.
Multi-annual funding programmes that define the EU’s priorities for research and innovation.
Topic(s)
Calls for proposals are divided into topics. A topic defines a specific subject or area for which applicants can submit proposals. The description of a topic comprises its specific scope and the expected impact of the funded project.
Data not available
Calls for proposals are divided into topics. A topic defines a specific subject or area for which applicants can submit proposals. The description of a topic comprises its specific scope and the expected impact of the funded project.
Call for proposal
Procedure for inviting applicants to submit project proposals, with the aim of receiving EU funding.
Data not available
Procedure for inviting applicants to submit project proposals, with the aim of receiving EU funding.
Funding Scheme
Funding scheme (or “Type of Action”) inside a programme with common features. It specifies: the scope of what is funded; the reimbursement rate; specific evaluation criteria to qualify for funding; and the use of simplified forms of costs like lump sums.
Funding scheme (or “Type of Action”) inside a programme with common features. It specifies: the scope of what is funded; the reimbursement rate; specific evaluation criteria to qualify for funding; and the use of simplified forms of costs like lump sums.
Data not available
Coordinator
71003 Iraklion - Crete
Greece
The total costs incurred by this organisation to participate in the project, including direct and indirect costs. This amount is a subset of the overall project budget.