Sound production is a widespread phenomenon in fishes; however, the importance of acoustic signals and their potential to influence reproduction has not been determined. This dissertation examines fish acoustic courtship signals to investigate whether sound has a role in reproductive success. The pre-spawning sounds of several fishes were recorded and analyzed. The male advertisement call of two species of Belizean toadfish, Sanopus astrifer and Batrachoides gilberti, were found to significantly differ. These data, coupled with data in the literature suggest an influence of habitat characteristics on the calling behavior of toadfishes. Additionally, acoustic playback experiments were employed to investigate the role of male courtship sounds in the Malawi cichlid species, Tramitichromis intermedius. Playback results indicated that male sounds may initiate egg-laying behavior in females, but may not be behaviorally relevant to conspecific males. A discussion of confounding factors in aquarium playback experiments is presented. Technical aspects of fish sound recording, playback, and analysis were also examined to provide information for future fish bioacoustics studies. It was determined that digital cameras are a useful method of recording fish sounds to describe metric characteristics; however, temporal parameters are more accurately captured by hydrophones, which are optimal for use in scientific description of fish sounds. Underwater speakers commonly used in fish playback experiments were tested for fidelity when producing a low-frequency pulsed fish sound. The Electro-Voice UW30 speaker was found to perform the best playback at low sound pressure levels (<120 dB re 1 μPa) and at short distances (< 15 cm). The Clark Synthesis AQ339 speaker performed the best playback at higher sound pressure levels (>120 dB re 1 μPa) and at greater distances than the UW30. Many fish sounds have been described in the literature; however, there is no standardization of sample size used in species descriptions. A method is presented that can be used to estimate the level of inclusiveness of sound variability in sound descriptions, and to approximate sufficient sample sizes of recordings. The courtship calls of Dascyllus albisella and Batrachoides gilberti were examined to illustrate this method and to provide a benchmark for future sound descriptions.

Memoria para optar al Título Profesional de Ingeniero Forestal / La creciente expansión de la población urbana ha implicado en una fuerte presión de esta sobre los distintos componentes del medioambiente, especialmente del medio biótico, restringiendo y desplazando a las formas de vida que lo componen. La vegetación presente dentro de las zonas urbanas es uno de los elementos biofísicos más importantes presentes en ellas, aportando no solo con detalles estéticos, sino que también con un sinnúmero de funciones y servicios ambientales que benefician tanto al medioambiente como a la población. El presente estudio tiene como objetivo evaluar el efecto del grado de senescencia de la vegetación urbana en la presencia de la especie Veniliornis lignarius (carpinterito), especie de pájaro carpintero catalogada como la más pequeña del país. En enero del presente año (2017), se realizó un muestreo de 203 puntos aleatorios en polígonos que contenían por lo menos un 25% de cobertura vegetal en comunas urbanas y adyacentes a la Cordillera de los Andes en la Región Metropolitana, aplicando el método de los cuartos y la técnica del Playback para una caracterización de la vegetación urbana y el registro de presencias o ausencias de carpinteritos respectivamente. Con los datos se creó un índice de senescencia para cada punto de muestreo, variable que fue sometida a un proceso de regresión logística binaria junto con las generadas por el método de los cuartos (densidad, volumen, área basal y altura), evaluando cual o cuales de estas fueron significativas en la predicción de la presencia de carpinteritos dentro del área de estudio. La única variable con un efecto significativo en la presencia de carpinteritos es el grado de senescencia de la vegetación urbana, en donde a mayor senescencia mayor es la probabilidad de presencia de la especie. La muestra representada por las ausencias de carpinteritos se concentra principalmente en arboles clasificados como “maduros”, mientras que la muestra de las presencias tiende a distribuir a los individuos en las clasificaciones “maduros”, “Senescente 1” y “Senescente 2”. / The increasing expansion of the urban population has implied a strong pressure of this on the different components of the environment, especially of the biotic resource, restricting and displacing the forms of life that take part of this. The vegetation present in urban areas is one of the most important biophysical elements present in them, contributing not only with aesthetic details, but also with a number of environmental functions and services that benefit, the environment and the population equally. The objective of this research is evaluate the effect of the different senescence levels of the urban vegetation, in the presence of the species Veniliornis lignarius (carpinterito), that is the smallest woodpecker species in the country. In January of 2017, was sampled 203 random points in polygons that contain at least 25% of vegetation cover in urban areas, nearby to the Andes Mountains in the Region Metropolitana, applying the quarter method and the Playback technique, for a characterization of the urban vegetation and the record of presences or absences of carpinteritos. With the data, a senescence index was created for each sampling point, this index was subjected to a binary logistic regression process, together with those generated by the quarter method (density, volume, basal area and height), to evaluate which of these were significant in the prediction of the presence of carpinteritos. The only variable with a significant effect on the presence of carpinteritos is the senescence levels of the urban vegetation, where the greater senescence is the probability of presence of the species. The sample represented by the absence of carpinteritos is mainly concentrated in trees classified as "Mature", while the presence sample tends to distribute to individuals in the "mature", "Senescent 1" and "Senescent 2" classifications.

LIPANSKÁ, B. 2011: Effect of alarm calls on tit's behavior on feeder. MSc Thesis. Faculty of Science, Charles University in Prague. Alarm calls of the Great tit (Parus major) used in the context of ground-predators or perching-raptors consist of high-frequency tonal syllables and of series of churring syllables with broad-frequency range. The function of some acoustical parametres of these complex calls was tested in playback experiment on feeder. As the most effective appeared to be alarm calling of two birds simultaneously. More important for warning function of the calls were broad-frequency range syllables. The length of series of these syllables had an opposite impact than in some north-American chickadees (genus Poecile). The Blue tit (Cyanistes caeruleus) responds to Great tit's alarm calls, but its reactions are weaker. This difference can be caused by its lower competition ability against the Great tit. Key words: antipredation behavior, alarm calls, tits, playback experiment

ABSTRACT In this dissertation I offer a critical review of ‘sound art’ in Johannesburg between 2005 and 2009. The term ‘sound art’ was coined by Dan Lander in 1989. According to Christoph Cox, Dan Lander’s lament that sound art lacked “any substantial discourse” in 1989 still applied in 2007. My intention in this research is to start such a critical discourse for sound art in Johannesburg. I argue that sound art is a distinctive practice in the city, involving the body politic and underground, surface and edge as characterised by Achille Mbembe and Sarah Nuttall in their recent major work on Johannesburg. First I briefly consider the history of sound art, referring to Brandon Labelle’s view that this history parallels that of site-specific art. I then suggest that the popularity of sound art under review became popular for a number of reasons; what Walter Ong’s termed “a shift in the sensorium”, the immediacy and inexpensiveness of working with sound, and the rise of the home computer. I also locate the sonic practices constituting sound art in audio culture as a whole, focussing on the structure, materiality, recording, playback and transmission of the sonic event in the sonic landscape. Sound, silence, noise and music are all part of this focus. I finally examine sound in terms of space, time, body and network in the work of Frances Goodman, Siobhan McCusker, The Trinity Session, Teamuncool, Gerhard Marx and my own sound work involving sampling, Happy Station (2008) and Slice Me Nice (2009).

When watching interactive branched video, the viewer is given the opportunity to tailor the storyline of the video playback. This type of video puts the users in control of their viewing experiences and provides content creators with great flexibility how to personalize the viewing experience for individual viewers. When it comes to regular linear videos, the concept of having a playback bar visually presenting the playback is a well established implementation used for most (if not all) video players, but for interactive branched videos, that is not the case. Instead, most branched video implementations are typically custom-made on a per-video basis (e.g., see custom-made Netflix and BBC movies) and do not use a playback bar. With the goal to fill this void, a branched video player with a generalized playback bar that visualizes the tree-like video structure was developed in 2018 by students of the Information Technology program at Linköping University and will be made public with a publication in the near future. Within the preparatory work prior to making this branched video player public, this project included a three-phase user study, where we evaluated the playback bar and its implemented features and compared the video player with alternative designs. With this thesis, we highlight the value of a branched video playback bar and provide interesting insights into how it, and other design customization features, may best be integrated into a branched video player. Furthermore, we present an improved version of the video player in which the new implementations are based on, and motivated by, the results from the user study. Finally, we describe how further investigations may be done to evaluate the improved version of the video player.

A long-standing goal of computer-based entertainment is the creation of a story where a user is in control of portions of the storyline. These non-linear stories give a user an opportunity to adapt the story to his or her interests, schedule and needs. The Internet has made non-linear video a reality. Different approaches have been taken to create and play non-linear video stories. They suffer from lack of simplicity, smoothness, and television-like experience in story creation and presentation. Flexible Storylines provide a way to easily create and present non-linear video stories. The creation of these stories is done using a time-line based editor that mimics the way video stories are composed by film makers. The viewing experience of flexible stories is very similar to viewing a normal video with an introduction of the choice to see more or less of the current topic. This provides a highly variable experience with a simple, smooth and non-intrusive form of user interaction. We also provide a mechanism that lets a story flow smoothly despite the introduction of user interaction.

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Magister en Ciencias Biológicas mención Ecología Facultad de Ciencias / Life-history attributes could be used to predict species responses to habitat fragmentation or sensitivity. We compared the incidence and sensitivity to fragmentation of four understory birds (Rhinocryptidae family). Rhinocryptids inhabit deciduous forests of Central Chile and our study was conduced in a landscape mosaic of pine (Pinus radiata) plantations and native forest fragments. Sensitivity was positively and strongly correlated with rhinocryptid incidence. Understory structure was the main factor that predicted rhinocryptid presence and abundance. The least sensitive species, Andean (Scytalopus magellanicus fuscus) and the Ochre-flanked Tapaculo (Eugralla paradoxa), were positively associated to dead pine branches and negatively to forest fragment size. Rhinocryptids reduced their abundance in mature forest, but they were willing to cross between different habitat types. However, one of the most sensitive species, Chestnut-throated Huet-Huet (Pteroptochos castaneus), did not move from forest fragments to pine with poor understory when we displayed playback trials. Overall, rhinocryptid species are affected by fragmentation depending of their life-history attributes. The less sensitive species profited from habitat and landscape transformations. We conclude that rhinocryptids could persist in this landscape, as changes in habitat conditions do not become deleterious, such as understory structure.

Nosso objetivo foi desenvolver um método para atestar a presença ou ausência de seis espécies de aves (Basileuterus leucoblepharus, Batara cinerea, Carpornis cucullatus, Chiroxiphia caudata, Pyriglena leucoptera e Trogon surrucura) em fragmentos florestais. Foi determinado o horário do dia e época do ano em que o play-back é mais eficiente em atestar a presença dessas aves. Os testes ocorreram na Reserva Florestal do Morro Grande (Cotia, SP). Três horários foram testados (manhã, meio do dia e tarde) ao longo de um ano. O teste G verificou a variação de eficiência entre os diferentes horários, e o teste de Rayleigh a variação anual. A manhã e o meio do dia apresentaram-se mais eficientes que a tarde para B. leucoblepharus, C. caudata e T. surrucura. A única ave a apresentar uma época do ano mais eficiente foi B. cinerea. Para avaliar sua eficiência, a capacidade do método em atestar a presença das aves em 13 fragmentos foi correlacionada com sua abundância nos mesmos. Os testes ocorreram quatro vezes em cada área nos momentos de maior eficiência. Os resultados indicam que C. caudata seja recenseada pelo menos duas vezes por fragmento. Três visitas é o mínimo para B. cinerea, B. leucoblepharus, P. leucoptera e T. surrucura. Para C. cucullatus deve-se ser repetir quatro vezes. O método foi criado para gerar rapidamente dados de presença e ausência em grande quantidade de fragmentos. Essa informação pode auxiliar estudos sobre dinâmica de metapopulações destas espécies. / In order to provide rapid access to presence/absence data of six species of birds (Basileuterus leucoblepharus, Batara cinerea, Carpornis cucullatus, Chiroxiphia caudata, Pyriglena leucoptera and Trogon surrucura) inside forest fragments, an efficient playback method was developed. The broadcast of these birds’ vocalizations was carried out at the Morro Grande Forrest Reserve (Cotia, SP). Playback tests were executed three times a day (sunrise, noon and before sunset) during one year. Daily and seasonal variations in the efficiency of the play-back were tested with G-statistics and the Rayleigh test. Sunrise and noon were more efficient than the period before sunrise to B. leucoblepharus, C. caudata and T. surrucura. The only species to show an annual period of higher rate of response was B. cinerea. To evaluate the real efficiency of the method, 13 forest fragments were surveyed for presence of these birds. The data was compared to the abundance of the birds in these areas. Each fragment was surveyed four times. At least two surveys are needed for C. caudata. Three surveys are the minimum effort to access the distributional pattern of B. leucoblepharus, B. cinerea, P. leucoptera and T. surrucura. Due to its rarity, C. cucullatus must be censused not less than four times. The method developed in the current study was created to provide a rapid access to the patch occupancy patterns of these six species in a large number of fragments. That kind of data may be very useful in studies about metapopulation dynamics and conservation ecology.