POPULATION DYNAMICS

Author: SANCHO RUBIO MARIA CRISTINA.
Year: 2002.
University: ZARAGOZA [www.unizar.es].
Place of defense: FACULTAD DE MEDICINA.
Place of preparation: UNIVERSIDAD DE ZARAGOZA.

Summary: BE TREATED FOR A STUDY CROSS DESCRIPTIVE. THE GOAL IS AWARE THE DISEASES OF A SHOW OF IMMIGRANT POPULATION TO BE ACUDIDO TO A REFERENDUM ON DEMAND FOR A PRIMARY CARE CENTER FOR THE YEAR 2001-2002. MEANT TO KNOW THE POWER PATOLOGIA MAS PREVALENTE FOR IDENTIFYING THE PROBLEM OF HEALTH AND THE ESTABLISHMENT OF PLANNING PROGRAMS AND HEALTH PREVENTION.

Author: ALONSO GUTIÉRREZ FERNANDO.
Year: 2004.
University: POLITÉCNICA DE MADRID [www.upm.es].
Place of defense: E.T.S. INGENIEROS DE MONTES.
Place of preparation: E.T.S. INGENIEROS DE MONTES.

Summary: It has been revised and updated bibliographic information available on the species. From these data are estimated at about 600 people, grouped into four broad geographic clusters, which survive in the Iberian Peninsula. To learn about the habitat preferences of the species in the Iberian sampling has been conducted on 134 points in the province of Cuenca. We have identified 38 populations Austropotamobius italicus, located primarily in small streams, isolated from the rest of the water system, and occupy stretches of very long, so their risk of extinction is high. There have been detected significant differences in the characteristics of the watershed and riparian habitat and river between streams occupied by crabs and those that are absent from the appearance of afanomicosis, suggesting that the mechanisms of dispersion this disease are responsible for the current distribution. About 40% of the population comes from localized reintroductions. Three populations were selected for the study of population dynamics and the evaluation of the effectiveness of electric fishing as sampling system, which took place 57 inventory over an annual cycle. The effectiveness of the electric fishing can be seen high in the sampled environments. This removes the bias towards sample sizes associated with other high sampling systems, although it has detected a selection of sizes not previously described. Among the disadvantages are detected the possible violation of the assumptions about the constancy of the likelihood of capture individual, the risks associated with the capture hand, the high rate of loss of tweezers and slow sampling. We have found significant variations in the age structure and growth, biomass and density of the populations studied. This occurs both between streams, as even in a very short distance within the same stream. The stations set within each band proved to be homogeneous with respect to these variables. The water temperature and conductivity are associated with differences in growth. Finally, it proposes a series of measures for the conservation of the species, structured in a recovery plan that includes strategies based on the conservation and recovery of the populations, research and testing, outreach, education and training and promoting commercialization of dead crabs.

Author: QUILES LUCAS JOSÉ ANTONIO.
Year: 2005.
University: LAS PALMAS DE GRAN CANARIA [www.ulpgc.es].
Place of defense: FACULTAD DE CIENCIAS DEL MAR.
Place of preparation: FACULTAD DE CIENCIAS DEL MAR.

Summary: The objectives in this Report are summarized in: A-Deepening the knowledge of biological shrimp soldier (Plesionika edwardsii) in Gran Canaria. B-description of an innovative technique of fishing in the Canaries' train shrimp floating masses "and their maneuvers fishing. C-identify specific selectivity of fishing gear in the interval batimérico prospectado. D-Determination of the size selectivity for the masses in the target species. E-estimate the extent of underwater platform useful, equivalent to Habitat waited for the species in the fishery island. F-Evaluation stock Plesionika edwardsii of Gran Canaria. G-Estimated fisheries potential of setock island shrimp soldier. H-Recommendations for interim measures for management of a fishery usual, under the hypothesis of biological and economic viability of this new fishery. The most significant results were obtained: L8 = 26.87 mm LC, k = 0.53 years - 1 and t0 =- 0030 for the total; L8 = 27.79 mm LC k = 0.47 years - 1 and to = -0050 males; L8 = 26.77 mm LC, k = 0.89 years -1 and t0 =- 0030 for females. The minimum size of maturity (TMM0, 05) was estimated at 15.6 billion LC and the stature of maturation (TMM0, 50) in 20.4 mm LC. The size of the 505 art retention was 20.12 mm LC. The potential fishing or maximum sustainable yield stock this island is estimón in 11690 kg annually. The total power of fishing on (PPR) that can be applied to capture 11690 kg annual shrimp soldier in Gran Canaria was estimated at 12, which translates into 12 boats with power units on (uppr)) 1, or any other combination of uppr that adds 12.

Author: MERINO CABRERA GORKA.
Year: 2006.
University: POLITÉCNICA DE CATALUÑA [www.upc.edu].
Place of defense: Sala 002 Edifici C-1.
Place of preparation: EDIFICI D1 Campus NORD.

Summary: The presented thesis resumes the techniques investigated for the construction of a bioeconomic model adequate to Mediterranean Fisheries. It is composed by a target species described by a global production model and a pool of secondary species. The population dynamics output are landings that after a market submodel become revenues. These revenues are transformed into net profits after the discounting of a detailed cost structure. One of the particularities of Mediterranean fisheries is the heterogeneity of its fleets, and as a consequence, a vessel level economic analysis is suggested. The GAMEFISTO model presents a game theoretic approach for the prediction of effort dynamics as its main novelty. This approach is based on Nash equilibrium (Nash, 1951) and the technical differences between the vessels of a fishery. Game theory is a tool to analyze the strategic interactions between the agents of a given exploitation. For natural resources this interaction is referred to the fact that what one user extracts will not be available for the other users (stock externality) and to the fact that one users landings will determine the sell price for the others. Fishermen in the actual Mediterranean management scheme can decide whether go fishing or not and the presented model describes such a decision. Fishing effort is expressed as days fishing and the presented model is proposed to explain the observed effort and catch trends in Mediterranean fisheries. The document starts with an introduction where the particularities of Mediterranean fishing systems and its problems are highlighted. These particularities suggest some variations on the traditional methodology of bioeconomic analysis that are reviewed in chapter I. Chapter II describes a game theoretic approach from the simplest models towards more complex ones to describe the total effort as a sum of a finite number of agents decisions. The effect of increasing the number of agents, the price dynamics and population dynamics effects are introduced to propose a realistic effort dynamics model. Chapter III reviews some parameter estimation techniques for the exploited species and the main novelty of genetic algorithms is introduced. Chapter IV is a detailed description of GAMEFISTO model. Chapter V presents a real case study analyzed with the proposed methodology. The first part of this chapter is a validation of game theory and genetic algorithms as useful techniques to implement in the current simulation knowledge of Mediterranean fisheries and in the GAMEFISTO model. The second pare of this chapter is a simulation exercise for the period from 2004 to 2014 of the Blanes red shrimp fishery with the GAMEFISTO model. Chapter VI contains a discussion and some considerations about the outcome of the analyzed fishery and the proposed methodology. Chapter VII is a list with the main conclusions of the present work.