Population viability and conservation of grey parrots psittacus erithacus on the island of Príncipe, Gulf of Guinea

Parrots are among the most endangered birds in the world, owing to the international pet trade, and habitat degradation. Grey Parrot Psittacus erithacus, the most traded wild-caught species, has suffered a steep decline across its vast African range. This PhD investigates Grey Parrot’s ecology to understand the mechanisms by which harvest and habitat loss affect populations. The island of Príncipe was chosen as a study area owing to its healthy Grey Parrot population, its tradition of parrot harvest and the disturbed-to-pristine range of habitats. Parrot densities were exceptionally high (mean±SE: 53±3 parrots km-1), and their distribution within the island was shown to change significantly between pre- and post-breeding season. The presence of nest tree species was the best predictor of densities in the former (F=2.99, p=0.07), while slope and food tree species were in the latter (F=3.0, p<0.05 and F=8.04, p<0.01). Variation in habitat use across seasons highlights the importance of opportunely timed surveys, and the need of preserving a matrix of habitats. Three simple and inexpensive methods were tested, which may be useful where more precise methods cannot be used. Simple encounter rates were shown to be a workable proxy for actual densities: a relationship was found between the two (R2=0.8, df=9, p=0.01). Long watches proved to be far less accurate and suitable only in limited cases (i.e. enough vantage points overlooking small areas and numerous encounters). Counts along flyways were suggested to be a good monitoring method, although further testing is required. Nest densities were found to be very high (mean±SE: 16.8±7.9 and 72.4±26.2 nests km-2 in secondary and primary forest respectively) compared to those elsewhere. The habitat characteristics measured didn’t affect productivity, suggesting that cavity characteristics may be more important. The best demographic data available on the species, were used to build a Population Viability Model to investigate its population dynamics in the face of harvest and habitat loss. In Príncipe, Grey Parrots were shown to have increased rapidly after a trade ban was put in place, highlighting the recovery potential of the species. Harvest alone was shown to be harmless only when small quotas (e.g. 600 chicks year-1) are yielded from large populations, while habitat loss lowered the predicted maximum population size. The interaction of these threats can be much more unpredictable. The effects of harvest are worsened if poorly regulated or techniques that include the harvesting of adults are used. Extinctions were predicted to occur with significant delay (≥40 years), and the conservation implications were discussed. Finally, the contribution of this thesis to the understanding of Grey Parrots ecology and conservation is highlighted and research priorities identified

Multi-view video acquisition with synchronized IP cameras

En este proyecto se propone integrar la captura de múltiples cámaras sincronizadas en la Smart Room de la UPC. La integración y el sincronismo se validarán mediante una aplicación de navegación en tiempo real espacio(cámara)-tiempo de las imágenes adquiridas para la generación de efectos de producción. Si es necesario, se recurrirá a algoritmos de código abierto de interpolación espacio temporal de OpenCV para la interpolación de imágenes intermedias en espacio y/o tiempoThe media world has changed as we know it. A few years ago we could not imagine having interactive televisions. We can now surf the web from the TV and save our favourite program to enjoy later. In this project we propose a new way to display our favourite events. With this system, the client can watch an event from the point of view that you want to live. The customer is no longer passive and becomes a participant of the action is happening. The main objective is to create a simple application for the user to choose the camera from which to observe the event. It is for this reason that synchronization is the cornerstone of the project. We studied different possibilities to carry out this idea and to solve the problems that have arisen. We find problems when performing streaming with two cameras, but will find a solution to this inconvenience. On the other side we can control the cameras and configure the parameters of interest. It is a fairly comprehensive and complex project and we could not get a final product for the customer by the time limitation. Therefore it will have to make further improvements. It has proved to be an interesting work, where I have learned many useful things for future projects. Besides all the work that I do can be helpful for other projects with these cameras. It could also be a final product that may interest companies that offer live events on Internet.El mundo multimedia ha cambiado mucho desde surgió. Hace unos años era impensable pensar que tendríamos una televisión interactiva, que podríamos navegar por la red y que incluso, podríamos gravar nuestros programas favoritos para verlos más tarde. Con este proyecto queremos ofrecer una nueva forma de visualizar los eventos importantes. Con este sistema el cliente puede escoger el punto de vista desde el que quiere ver un suceso como por ejemplo, un partido de fútbol. El cliente deja de ser un elemento pasivo a ser partícipe de la acción que está sucediendo en ese momento. Por lo tanto, el objetivo principal es crear una aplicación simple desde la cual la persona pueda seleccionar la cámara que más le interese. Por este motivo, la sincronización es muy importante en este proyecto. Hemos estudiado las diferentes opciones para realizar esta idea y los problemas que irán surgiendo. Encontraremos problemas sobre todo en la parte de streaming con dos cámaras y conseguiremos una manera de solucionarlo. Por otro lado, podremos controlar perfectamente las cámaras que usaremos y configurarlas con los valores que creamos mejores. Ha resultado ser un trabajo muy completo y a la vez, muy complejo y no se ha podido llegar a obtener una aplicación por la falta de tiempo. Aunque creemos que se podrán hacer mejores más adelante. Ha sido un proyecto interesante i del cual he aprendido muchas cosas útiles que me ayudarán en futuros proyectos que realice. Además, se puede aprovechar este trabajo para futuros proyectos que se realicen con estas cámaras. Como última conclusión, indicar que podría ser un producto que podría interesar a las empresas que se dedican a difundir eventos en directo por internet.El món multimèdia ha canviat molt des de que va sorgir. Fa uns anys era impensable pensar que tindríem una televisió interactiva, que podríem navegar per la xarxa i, fins i tot, gravar els nostres programes favorits per veure’ls més tard. Amb aquest projecte volem oferir una nova forma de visualitzar els esdeveniments importants. Des d’aquest sistema el client pot escollir el punt de vista que desitgi per veure un succés com, per exemple, un partit de futbol. El client deixa de ser un element passiu a ser partícip de l’acció que està succeint en aquell moment. Per tant, l’objectiu principal és crear una aplicació simple des de la qual la persona pugui seleccionar la càmera que més li interessi en aquell moment. Per aquest motiu, la sincronització és molt important en aquest projecte. Hem estudiat les diferents opcions per realitzar aquesta idea i els problemes que aniran sorgint. Trobarem problemes sobretot amb la part d’streaming amb dues càmeres i trobarem una manera per arreglar-ho. Però per una altra banda, podrem controlar perfectament les càmeres que utilitzarem i configurar-les amb els valors més adients. Ha resultat ser un treball molt complet i a la vegada, molt complex i no s’ha pogut obtenir una aplicació o producte final per la falta de temps. Encara que es podran fer millores més endavant. Ha sigut un projecte interesant i del qual he après moltes coses útils que m’ajudaran en futurs projectes que realitzi. A més a més, es podrà aprofitar aquest treball per a futurs projectes que es realitzin amb aquestes càmeres. Com a última conclusió, indicar que podria ser un producte que podria interessar a les empreses que es dediquen a difondre esdeveniments en directe per internet

What can the abundance of Grey Parrots on Príncipe Island tell us about large parrot conservation?

While populations of the Endangered Grey Parrot Psittacus erithacus have collapsed across its range, the species remains remarkably abundant on the island of Príncipe, Gulf of Guinea. We examine how aspects of its ecology interplay with local environmental conditions, to inform conservation strategies for this species and other large parrots. On Príncipe, parrots breed in large trees of common species, with nest densities (42 ± 34 km-2) greatly exceeding those for any comparably sized parrot. Productivity is high (1.9 chicks per cavity), probably reflecting the absence of nest competitors and predators. Food sources are abundant and much of the island is inaccessible to trappers, so many nests are successful each year. Historically harvest has involved taking only chicks from trees in a few traditional patches. These conditions have combined to allow Grey Parrots to thrive on Príncipe, while elsewhere nest trees are timber targets, nest competition and nest predation are likely to be more intense, trapping is indiscriminate, and few areas remain unexploited by trappers. Preservation of large trees as breeding refugia, and vigilance against the indiscriminate trapping of adult birds, are identified as key conditions to stabilize and recover mainland Grey Parrot populations and indeed large parrots generally, given their very similar ecological traits and anthropogenic circumstances

2D Fractional Supersymmetry for Rational Conformal Field Theory. Application for Third-Integer Spin States

A 2D- fractional supersymmetry theory is algebraically constructed. The Lagrangian is derived using an adapted superspace including, in addition to a scalar field, two fields with spins 1/3,2/3. This theory turns out to be a rational conformal field theory. The symmetry of this model goes beyond the super Virasoro algebra and connects these third-integer spin states. Besides the stress-momentum tensor, we obtain a supercurrent of spin 4/3. Cubic relations are involved in order to close the algebra; the basic algebra is no longer a Lie or a super-Lie algebra. The central charge of this model is found to be 5/3. Finally, we analyse the form that a local invariant action should take.Comment: LaTex, 20 pages. Revised in response to referees' Comment

Conditional accuracy in response interference tasks: Evidence from the Eriksen flanker task and the spatial conflict task

Two well-known response interference tasks are the Eriksen flanker task and the spatial conflict task. The tasks are logically equivalent, and comparable effects of current and previous stimulus type (congruent or incongruent) have been shown with regard to reaction time (RT). Here, we investigated whether interference and sequential trial effects also had comparable effects on accuracy. We specifically tested whether these effects interacted with the speed of responding using conditional accuracy functions (CAFs). The CAFs revealed that in both tasks congruency and sequential trial effects on accuracy are found only in trials with fast responses (< 600 ms). Sequential trial effects on accuracy were weaker for the flanker task than for the spatial conflict task. In very fast trials (< 400 ms) response activation by distracting flankers led to below-chance performance in the flanker task, but response activation by incongruent spatial location did not lead to below-chance performance in the spatial conflict task. The pattern of results hints at subtle differences in processing architecture between the tasks

External coding and salience in the tactile Simon effect

Previous studies have demonstrated a tactile Simon effect in which stimulus codes are generated based on the stimulated hand, not on limb position in external space (the somatotopic Simon effect). However, given evidence from visual Simon effect studies demonstrating that multiple stimulus codes can be generated for a single stimulus, we examined whether multiple stimulus codes can be generated for tactile stimuli as well. In our first experiment using four stimulators (two on each side of the hand), we found novel evidence for a hand-centered Simon effect, along with the typical somatotopic Simon effect. Next, we examined whether the potential salience of these somatotopic codes could be reduced, by testing only one hand with two stimulators attached. In Experiments 2\u20134, we found a strong hand-centered Simon effect with a diminished somatotopic Simon effect, providing evidence that stimulus salience can change the weighting of somatosensory stimulus coding. Finally, we also found novel evidence that the hand-centered Simon effect is coded in external, not somatotopic, coordinates. Furthermore, the diminished somatotopic Simon effect when testing on one hand only provides evidence that salience is an important factor in modulating the tactile Simon effect