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A theodolite control program for the acquisition of MLS flight check aircraftMatthews, John V., Jr. January 1983 (has links)
No description available.
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Ακριβής συγχρονισμός ρομποτικού θεοδόλιχου (RTS) και GPS με πειραματικές και αναλυτικές μεθόδουςΚαριζώνης, Μιχάλης 12 August 2011 (has links)
Τα τελευταία χρόνια, υπάρχει μια αλματώδης εξέλιξη στην τεχνολογία των τοπογραφικών οργάνων και των γεωδιατικών εφαρμογών. Τα νέα όργανα συνδυάζουν διαφορετικές τεχνολογίες που βοηθούν το χρήστη να διορθώνει αυτόματα οποιαδήποτε σφάλματα προκύπτουν, κυρίώς όσον αφορά στο χρόνο. Χαρακτηριστικό παράδειγμα αποτελεί ο συνδυασμός ρομποτικού θεοδόλιχου (RTS) με δέκτη GPS προσαρμοσμένο επάνω του.
Όμως, τα καινούρια αυτά όργανα αφ’ενός έχουν υψηλό κόστος και αφ’ετέρου δεν είναι ακόμα ευρέως διαδεδομένα. Στην παρούσα διπλωματική εργασία γίνεται έρευνα για το πως μπορούν να συγχρονιστούν οι καταγραφές δύο διαφορετικών οργάνων (RTS και GPS), τα οποία καταγράφουν την ίδια κίνηση ταυτόχρονα.
Η διερεύνηση του συγχρονισμού προκύπτει από επεξεργασία μετρήσεων μιας σειράς είκοσι πειραμάτων, που αποτελούνται από μετακίνηση στήλου επάνω σε ράγα. Στη συνέχεια αναπτύσσεται μοντέλο επεξεργασίας των πειραμάτων, ώστε να βρεθεί ο βέλτιστος τρόπος συγχρονισμού των οργάνων μέσω της εύρεσης των πιο αξιόπιστων πειραμάτων. / In recent years, there is a rapid development in technology, surveying and geodiatikon applications. The new instruments combine different technologies that help the user to automatically correct any errors occur, notably at the time. An example is the combination of robotic theodolite (RTS) with a GPS receiver adapted on it.
But the new institutions on the one hand they have high costs and on the other hand is not yet widespread. This thesis research on how to synchronize the recording of two different organs (RTS and GPS), which record the same movement simultaneously.
The investigation of synchronization resulting from processing a series of twenty measurements experiments, consisting of a column moving on track. Then a model processing of experiments is developed to find the best way to synchronize the instrument by finding the most reliable experiments.
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Razões trigonométricas: uma abordagem do cotidianoVassallo, Victor Hugo 14 March 2017 (has links)
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Previous issue date: 2017-03-14 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Este trabalho foi desenvolvido a partir da necessidade do estudo das Razões Trigonométricas. Em geral, sabemos que no ensino básico a Matemática se apresenta de forma descontextualizada. Propomosaquiumaabordagemhistóricadesteassuntoeaformacomo é apresentada nos livros didáticos. A partir daí, apresentamos uma série de atividades que envolve construções realizadas com régua e compasso, utilização de um software de geometria dinâmica e a montagem de um teodolito. O objetivo desta proposta baseia-se na possibilidade de se trabalhar este material em uma turma da 1a série do ensino médio mesmo em uma escola com poucos recursos, mostrando que é possível estudar matemática relacionando-a às necessidades que permeiam a humanidade há séculos. / This work was developed from the necessity of the study of Trigonometric Reasons. In general, we know that in the basic education the Mathematics presents itself in a decontextualized way. We propose here a historical approach to this subject and the way it is presented in textbooks. From there, we present a series of activities that involve constructions performed with ruler and compass, use of dynamic geometry software and the assembly of a theodolite. The objective of this proposal is based on the possibility of working this material in a class of the 1st grade of high school even in a school with few resources, showing that it is possible to study mathematics relating it to the needs that have permeated humanity for centuries.
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A geometria plana no ensino fundamental: estudo prático sobre o teodolito / The plane geometry in elementary school: pratical study of the theodoliteAmorim, Jose Alves de 14 June 2016 (has links)
Este trabalho teve como finalidade o estudo prático de construção de figuras geométricas utilizando instrumentos disponíveis na própria escola. A situação problema apresentada buscou verificar como pode ser possível determinar a medida de regiões inacessíveis através de cálculos e relações geométricas. Para alcançar o objetivo proposto, ou seja, a utilização prática deste instrumento de medida foi realizada a construção de um Teodolito caseiro, com materiais de baixo custo e que estavam à disposição na própria escola. Por fim, as medidas e os cálculos realizados pelos alunos foram discutidos em sala de aula, analisando possíveis dificuldades e conhecimento adquiridos durante o processo de ensino aprendizagem. / This work aimed to study the practical construction of geometric figures using tools available at the school. The problem situation presented aims to evaluate how it can be possible to determine the extent of inaccessible areas by calculation and geometric relationships. To achieve the proposed objective, the practical use of this measuring instrument, building a Theodolite \"homemade\" was held, with low-cost materials that were available at the school. Finally, the measurements and calculations performed by the students were discussed in class, analyzing possible difficulties and knowledge acquired during the teaching-learning process.
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A geometria plana no ensino fundamental: estudo prático sobre o teodolito / The plane geometry in elementary school: pratical study of the theodoliteJose Alves de Amorim 14 June 2016 (has links)
Este trabalho teve como finalidade o estudo prático de construção de figuras geométricas utilizando instrumentos disponíveis na própria escola. A situação problema apresentada buscou verificar como pode ser possível determinar a medida de regiões inacessíveis através de cálculos e relações geométricas. Para alcançar o objetivo proposto, ou seja, a utilização prática deste instrumento de medida foi realizada a construção de um Teodolito caseiro, com materiais de baixo custo e que estavam à disposição na própria escola. Por fim, as medidas e os cálculos realizados pelos alunos foram discutidos em sala de aula, analisando possíveis dificuldades e conhecimento adquiridos durante o processo de ensino aprendizagem. / This work aimed to study the practical construction of geometric figures using tools available at the school. The problem situation presented aims to evaluate how it can be possible to determine the extent of inaccessible areas by calculation and geometric relationships. To achieve the proposed objective, the practical use of this measuring instrument, building a Theodolite \"homemade\" was held, with low-cost materials that were available at the school. Finally, the measurements and calculations performed by the students were discussed in class, analyzing possible difficulties and knowledge acquired during the teaching-learning process.
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Měření pozice pohybujících se objektů pomocí robotické totální stanice / Position measurement of moving objects using a robotic total stationHoreličan, Tomáš January 2021 (has links)
Práca sa zaoberá objavujúcim sa nekonvenčným využitím moderných teodolitov, tiež známych ako Robotické Totálne Stanice (RTS), ako sledovací a navádzací systém, určením presnej pozície dynamicky sa pohybujúceho objektu. To sa týka najmä situácií, kde nie je možné využiť konvenčné polohovacie systémy akým je napríklad GNSS. Kinematicky určená poloha objektu kontinuálne sledujúcou RTS môže byť následne v reálnom čase využitá pre autonómnu navigáciu malých bezpilotných leteckých prostriedkov (UAV) poskytnutím referenčného súradnicového systému a okamžitej polohy v ňom. Podstatná časť práce je venovaná návrhu a realizácii vhodných experimentov, ktoré overia spoľahlivosť určovania presnej polohy objektu v presnom časovom okamžiku. Boli preverené stanice série S7 a S9 od spoločnosti Trimble a stanica S9 HP, ktorá disponuje frekvenciou kontinuálneho merania až do 10 Hz bola napokon využitá pre experimenty. Lokálny čas ovládacieho panelu TSC7, ktorý zabezpečuje komunikáciu so stanicou bol pomocou protokolu PTP synchronizovaný s lokálnym časom mini-počítača Raspberry Pi, ktorý následne poskytoval referenčné meranie skutočnej polohy objektu v čase. V závere sú zhrnuté výsledky experimentov.
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Boat preference and stress behaviour of Hector's dolphin in response to tour boat interactionsTravis, Georgia-Rose January 2008 (has links)
Dolphins are increasingly coming into contact with humans, particularly where tourism is involved. It has been assumed that such contact causes chronic stress on dolphin populations. This study examined relatively naive populations of Hector's dolphins and their interaction with various watercrafts. Dolphins in New Zealand have been observed using theodolites and boat-based observations over the last two decades, particularly on the east side of the South Island at Akaroa, which is situated on the coast line of Banks Peninsula. This research was undertaken using shore-based theodolite tracking to observe boat activity around the coast of Lyttelton and Timaru and their associated Harbours. Observations were made mostly over two periods each of six months duration and included the months October through to March during the years 2000-2001 and 2001-2002. Observations made during a third period in 2005 were also incorporated for some of the analyses. Field investigations using a theodolite included more than 376 hours/site/season and recorded dolphin behaviour both with and without the presence of tour boats. Of primary interest were the tours, which ran regular trips to observe Cephalorhynchus hectori in their natural habitat. Hector's dolphins at both Lyttelton and Timaru were consistently observed with particular boat types and not with other types of water craft. Dolphins at Timaru exhibited a greater range of behaviours than those at Lyttelton. Stress-related behaviours such as an increase in swimming speed to open ocean and grouping behaviour were only observed in the presence of boats. Other potential stress behaviours, such as head slaps and repeated tail slaps, were only performed in the absence of boats. Observations implied that some generic dolphin behaviours, which often indicate stressed individuals may not apply to Hector's dolphins, and therefore question the assumption that all dolphin species behave in similar ways. We suggest that low-level tourist boat activity is not placing undue stress on the population. In addition to theodolite observations, tour boat based observations of Hector's dolphin were undertaken and behaviour at each site recorded for a focal animal. Tour boat-based observations concentrated on determining any preference to bow, stern, portside and starboard sides of the vessel. Dolphins consistently showed a preference in direction of approach and departure from tour vessels with a strong tendancy to the bow of the boat, and least with the stern. These results were similar irrespective of site or vessel. Behaviour data were also collected from tour boat vessels over 48 trips/season/site and the data divided into transitional behaviour groups, which included stress behaviours, association / interaction behaviour and neutral behaviour. Behavioural count and time data were collected to reflect the number of times and duration of behaviour occurrence, particularly in relation to transitional behaviours. Determining the presence of stress in Hector's dolphins varied between the data sets and indicated that time is a necessary factor when attempting to determine whether an individual or a general population is genuinely stressed. Quadrant preference and swimming direction in relation to the Black Cat were observed over six years, and both count and time data were collected with regard to behaviour. The results were consistent with preference in quadrant being expressed towards the bow of the boat and least with the stern. The count data suggested no significant impact on Hector's dolphin behaviour in the presence of the Black Cat over time, where time data indicated there was a transition over the years from neutral behaviour in the second year of tour boat activity, to positive behaviour in the third year of boat-activity and finally avoidance behaviour in the seventh year of tour boat activity at Lyttelton Harbour in response to the presence of the Black Cat.
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Entwicklung, Kalibrierung und Erprobung eines kameraunterstützten Hängetachymeters / Development, calibration and testing of a camera assisted suspended tacheometerKnoblach, Stefan 08 December 2009 (has links) (PDF)
Trotz aller technischen Weiterentwicklungen in der Vergangenheit unterscheiden sich moderne elektronische Tachymeter in ihrer Grundkonstruktion nicht wesentlich von ihren analogen Vorgängern. Ihnen allen ist gemeinsam, dass eine Visur um den Nadir nicht möglich ist. Dies bedeutet, dass Punkte, welche sich in einem Zenitwinkelbereich zwischen ca. 170 und 230 gon befinden, nicht direkt gemessen werden können.
Gegenstand der vorliegenden Arbeit war daher die Entwicklung eines Systems, mit welchem tachymetrische Messungen auch in einem Zenitwinkelbereich zwischen 170 und 230 gon möglich sind. Das Konzept basiert auf dem aus dem Markscheidewesen bekannten Hängetheodolit. Um Messungen im Bereich des Nadirs durchführen zu können, wird ein Tachymeter ähnlich einem Hängetheodolit in hängender Position montiert. In dieser Position ist der zur Horizontierung dienende interne elektronische Neigungskompensator jedoch nicht funktionsfähig. Die Horizontierung wird daher extern überwacht. Zu diesem Zweck wird das Tachymeter über eine geeignete Aufhängevorrichtung mit einem Neigungssensor verbunden. Die Kombination aus in hängender Position montiertem Tachymeter und externem Neigungssensor wird als Hängetachymeter bezeichnet.
Bei der Kombination des Systems mit einem externen Neigungssensor kann eine geringe Abweichung zwischen der Stehachse des Tachymeters und der Lotachse des Neigungssensors fertigungsbedingt nicht vermieden werden. Zur Bestimmung dieser Abweichung wurden geeignete Verfahren entwickelt und auf ihre Genauigkeit untersucht.
Die mit dem Tachymeter ermittelten Messwerte werden durch Instrumentenabweichungen beeinflusst und müssen um diese korrigiert werden. Auch sind die Messwerte um die mit dem externen Neigungssensor ermittelte Stehachsenneigung zu korrigieren. Die Achsenabweichungen des Tachymeters müssen in hängender Position bestimmt werden. Es kann nicht generell vorausgesetzt werden, dass diese mit den in aufrechter Position bestimmten Werten übereinstimmen.
Zur Steuerung des Hängetachymeters wurde eine Software entwickelt, in welche die Kalibrierung der Sensoren, die Auswertung und Korrektur der Messwerte, deren Speicherung und Weiterverarbeitung sowie der Datenexport integriert wurden.
Eine Kombination des Hängetachymeters mit einer Okularkamera ermöglicht die automatische Zielerkennung und -verfolgung nichtsignalisierter Punkte auch bei Messungen nahe dem Nadir. Zur Realisierung eines Autofokus wurde das Hängetachymeter mit einem Schrittmotor kombiniert, welcher über den Fokussierring des Tachymeters die Fokussierlinse bewegt. Eine Autofokusfunktion wurde auf Grundlage des Bildkontrastes entwickelt.
Die Kalibrierung der Okularkamera basiert auf einer Modellierung des Abbildungsprozesses durch lineare Funktionen. Hierbei wurde die Abhängigkeit der Kalibrierwerte von der Position der Fokussierlinse (Position des Schrittmotors) aufgezeigt.
Die zur optischen Zielerkennung eingesetzten Bildverarbeitungsalgorithmen gliedern sich in eine manuelle Punktanzielung im Bild, die Messung punktförmiger Muster durch Kantendetektion und Ellipsenanpassung und Bildzuordnungsverfahren nach der Methode der kleinsten Quadrate.
Um die Leistungsfähigkeit des Hängetachymeters zu bestimmen, aber auch um die Güte der Kalibrierung zu testen, wurden mehrere Genauigkeitsuntersuchungen durchgeführt. Abschließend wurde das Hängetachymeter auch erfolgreich in der Industrievermessung eingesetzt und eine automatische Kalibrierroutine ohne Interaktion des Benutzers entwickelt. Die erreichten Genauigkeiten des Systems liegen im Bereich der Genauigkeiten des eingesetzten Tachymeters. / Despite all technical enhancements in the past modern electronic tacheometers do not differ significantly to their analogue predecessors. All have in common that aiming around the nadir is not possible. This means that points situated in the zenith angle region between ca. 170 to 230 gon cannot be measured directly.
Therefore the subject of the present work was the development of a system that makes measurements in the zenith angle region between 170 and 230 gon possible. The concept is based upon the suspended theodolite which is known in mine-surveying. To carry out measurements in the region of the nadir a total station is mounted in a hanging position similar to a suspended theodolite. However the function of the tilt compensator which is used for levelling of the instrument is not supported in this position. Hence inclination is monitored externally. For this purpose the tacheometer is connected to a clinometer by an appropriate suspension arrangement. The combination of a tacheometer mounted in a suspended position and an external clinometer is called suspended tacheometer.
Combining the system with an external clinometer a marginal variation occurs between the vertical axis of the tacheometer and the plummet axis of the clinometer due to production conditions. To quantify this variation an appropriate method was developed and its accuracy tested.
Measurements conducted by the tacheometer are influenced by the variations of the instrument and must therefore be adjusted. Moreover these measurements must be adjusted by the inclination detected by the external clinometer. The axis variations of the tacheometer must be determined in suspended position. It cannot be generally presumed that these measurements comply with the ones determined in upright position.
To actuate the suspended tacheometer a software was developed. This software also offers integrated functions for calibration of the sensors, analysis and adjustment of the measurements and their storage and processing as well as export of data.
A combination of the suspended tacheometer with an ocular camera makes automatic target detection and tracking of non-cooperative signals possible also when measuring near the region of the nadir. To realize an autofocus the suspended tacheometer was combined with a stepper motor which moves the focus lens. Based on the image contrast an autofocus function was developed.
The calibration of the ocular camera is based on modelling the mapping process by linear functions. Here the dependency of calibration values on the position of the focus lens (position of the stepping motor) was demonstrated.
Image processing algorithms used for optical target detection can be divided into manual target detection in the image, measurement of point-shaped patterns by edge detection and ellipse adjustment and image allocation operations (Least squares matching).
To determine the efficiency of the suspended tacheometer as well as to test the performance of the calibration several accuracy tests were performed. Also the suspended tacheometer was successfully deployed in industrial surveying. An automatic calibration routine without participation of a user was developed. The achieved accuracies of the system correspond with the accuracies of the inserted tacheometer.
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Entwicklung, Kalibrierung und Erprobung eines kameraunterstützten HängetachymetersKnoblach, Stefan 20 October 2009 (has links)
Trotz aller technischen Weiterentwicklungen in der Vergangenheit unterscheiden sich moderne elektronische Tachymeter in ihrer Grundkonstruktion nicht wesentlich von ihren analogen Vorgängern. Ihnen allen ist gemeinsam, dass eine Visur um den Nadir nicht möglich ist. Dies bedeutet, dass Punkte, welche sich in einem Zenitwinkelbereich zwischen ca. 170 und 230 gon befinden, nicht direkt gemessen werden können.
Gegenstand der vorliegenden Arbeit war daher die Entwicklung eines Systems, mit welchem tachymetrische Messungen auch in einem Zenitwinkelbereich zwischen 170 und 230 gon möglich sind. Das Konzept basiert auf dem aus dem Markscheidewesen bekannten Hängetheodolit. Um Messungen im Bereich des Nadirs durchführen zu können, wird ein Tachymeter ähnlich einem Hängetheodolit in hängender Position montiert. In dieser Position ist der zur Horizontierung dienende interne elektronische Neigungskompensator jedoch nicht funktionsfähig. Die Horizontierung wird daher extern überwacht. Zu diesem Zweck wird das Tachymeter über eine geeignete Aufhängevorrichtung mit einem Neigungssensor verbunden. Die Kombination aus in hängender Position montiertem Tachymeter und externem Neigungssensor wird als Hängetachymeter bezeichnet.
Bei der Kombination des Systems mit einem externen Neigungssensor kann eine geringe Abweichung zwischen der Stehachse des Tachymeters und der Lotachse des Neigungssensors fertigungsbedingt nicht vermieden werden. Zur Bestimmung dieser Abweichung wurden geeignete Verfahren entwickelt und auf ihre Genauigkeit untersucht.
Die mit dem Tachymeter ermittelten Messwerte werden durch Instrumentenabweichungen beeinflusst und müssen um diese korrigiert werden. Auch sind die Messwerte um die mit dem externen Neigungssensor ermittelte Stehachsenneigung zu korrigieren. Die Achsenabweichungen des Tachymeters müssen in hängender Position bestimmt werden. Es kann nicht generell vorausgesetzt werden, dass diese mit den in aufrechter Position bestimmten Werten übereinstimmen.
Zur Steuerung des Hängetachymeters wurde eine Software entwickelt, in welche die Kalibrierung der Sensoren, die Auswertung und Korrektur der Messwerte, deren Speicherung und Weiterverarbeitung sowie der Datenexport integriert wurden.
Eine Kombination des Hängetachymeters mit einer Okularkamera ermöglicht die automatische Zielerkennung und -verfolgung nichtsignalisierter Punkte auch bei Messungen nahe dem Nadir. Zur Realisierung eines Autofokus wurde das Hängetachymeter mit einem Schrittmotor kombiniert, welcher über den Fokussierring des Tachymeters die Fokussierlinse bewegt. Eine Autofokusfunktion wurde auf Grundlage des Bildkontrastes entwickelt.
Die Kalibrierung der Okularkamera basiert auf einer Modellierung des Abbildungsprozesses durch lineare Funktionen. Hierbei wurde die Abhängigkeit der Kalibrierwerte von der Position der Fokussierlinse (Position des Schrittmotors) aufgezeigt.
Die zur optischen Zielerkennung eingesetzten Bildverarbeitungsalgorithmen gliedern sich in eine manuelle Punktanzielung im Bild, die Messung punktförmiger Muster durch Kantendetektion und Ellipsenanpassung und Bildzuordnungsverfahren nach der Methode der kleinsten Quadrate.
Um die Leistungsfähigkeit des Hängetachymeters zu bestimmen, aber auch um die Güte der Kalibrierung zu testen, wurden mehrere Genauigkeitsuntersuchungen durchgeführt. Abschließend wurde das Hängetachymeter auch erfolgreich in der Industrievermessung eingesetzt und eine automatische Kalibrierroutine ohne Interaktion des Benutzers entwickelt. Die erreichten Genauigkeiten des Systems liegen im Bereich der Genauigkeiten des eingesetzten Tachymeters. / Despite all technical enhancements in the past modern electronic tacheometers do not differ significantly to their analogue predecessors. All have in common that aiming around the nadir is not possible. This means that points situated in the zenith angle region between ca. 170 to 230 gon cannot be measured directly.
Therefore the subject of the present work was the development of a system that makes measurements in the zenith angle region between 170 and 230 gon possible. The concept is based upon the suspended theodolite which is known in mine-surveying. To carry out measurements in the region of the nadir a total station is mounted in a hanging position similar to a suspended theodolite. However the function of the tilt compensator which is used for levelling of the instrument is not supported in this position. Hence inclination is monitored externally. For this purpose the tacheometer is connected to a clinometer by an appropriate suspension arrangement. The combination of a tacheometer mounted in a suspended position and an external clinometer is called suspended tacheometer.
Combining the system with an external clinometer a marginal variation occurs between the vertical axis of the tacheometer and the plummet axis of the clinometer due to production conditions. To quantify this variation an appropriate method was developed and its accuracy tested.
Measurements conducted by the tacheometer are influenced by the variations of the instrument and must therefore be adjusted. Moreover these measurements must be adjusted by the inclination detected by the external clinometer. The axis variations of the tacheometer must be determined in suspended position. It cannot be generally presumed that these measurements comply with the ones determined in upright position.
To actuate the suspended tacheometer a software was developed. This software also offers integrated functions for calibration of the sensors, analysis and adjustment of the measurements and their storage and processing as well as export of data.
A combination of the suspended tacheometer with an ocular camera makes automatic target detection and tracking of non-cooperative signals possible also when measuring near the region of the nadir. To realize an autofocus the suspended tacheometer was combined with a stepper motor which moves the focus lens. Based on the image contrast an autofocus function was developed.
The calibration of the ocular camera is based on modelling the mapping process by linear functions. Here the dependency of calibration values on the position of the focus lens (position of the stepping motor) was demonstrated.
Image processing algorithms used for optical target detection can be divided into manual target detection in the image, measurement of point-shaped patterns by edge detection and ellipse adjustment and image allocation operations (Least squares matching).
To determine the efficiency of the suspended tacheometer as well as to test the performance of the calibration several accuracy tests were performed. Also the suspended tacheometer was successfully deployed in industrial surveying. An automatic calibration routine without participation of a user was developed. The achieved accuracies of the system correspond with the accuracies of the inserted tacheometer.
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Utilisation de l’habitat et pressions anthropiques sur une population de rorquals à bosse (Megaptera novaeangliae) de Guadeloupe par suivi terrestreProulx, Bruno 10 1900 (has links)
Le sanctuaire Agoa est une aire marine protégée dans la zone économique exclusive (ZEE) des Antilles françaises qui fut créée en 2010 pour la conservation des mammifères marins et de leurs habitats. Il est connu que le rorqual à bosse fréquente les eaux des Antilles de décembre à mai pour la reproduction et la mise bas. Par contre, peu d’information existe sur l’abondance, le comportement, la distribution et les pressions anthropiques sur cette espèce aux Antilles et encore moins dans le sanctuaire. Cette maîtrise s’intéresse principalement à connaître cette espèce dans un secteur précis de cette aire marine et les liens qu’elle entretient avec certains utilisateurs humains de son habitat. Le tout vise à informer les intervenants en place, autant institutionnels qu’utilisateurs, vers une mise en place de mesures de conservation adaptées.
Un suivi terrestre hivernal de plus de 300 heures, en 2012 et 2013, a permis de déterminer l’utilisation de l’habitat et les pressions anthropiques sur une population de rorquals à bosse fréquentant le sud de la péninsule de la Pointe-des-Châteaux en Guadeloupe. Il s’agit du premier suivi terrestre de cette espèce aux Antilles françaises et un des premiers dans l'arc caribéen. La zone d’étude couvre environ 264 km2 et serait une des zones les plus fréquentées de l’archipel guadeloupéen par l’espèce. À l’aide d’un théodolite, la trajectoire de 107 groupes différents (137,8 heures, 699 remontées) a été décrite.
Les résultats montrent que la zone d’étude est principalement fréquentée en mars et avril, avec une abondance maximale au début du mois d’avril. La forte présence de baleineaux, particulièrement au mois de mars, pousse à croire que cette zone est utilisée comme pouponnière. Le comportement n’est pas aléatoire dans la zone d’étude et les trajectoires convergent vers certaines zones ayant possiblement un lien avec la bathymétrie. De plus, la zone marine à proximité de la Pointe-des-Châteaux pourrait potentiellement être un lieu de convergence des groupes. Ceux-ci se déplacent à vitesse réduite en direction ENE en général, à l’exception des femelles accompagnées de baleineaux qui prennent une orientation tout autre, c’est-à-dire vers le ONO, et ce à plus grande vitesse. Bien que la pression d’observation soit considérée comme modérée, une forte proportion des remontées se trouve dans les corridors de navigation présents dans la zone d’étude. De plus, le corridor de navigation des navettes entre Saint-François et La Désirade comporte le plus grand risque relatif de collision mortelle.
Une réduction de vitesse des embarcations fréquentant le corridor des navettes diminuerait significativement le risque de collision mortelle. Ces pistes de réflexion mèneront sans doute à d’autres études plus poussées afin de continuer à en apprendre sur l’écologie de cette espèce fascinante. / The Agoa sanctuary, a marine protected area (MPO) covering the exclusive economic zone (EEZ) in the French Caribbean, was created in 2010 to protect marine mammals and their habitats. It is known that the Caribbean islands are used from December to May by humpback whales (Megaptera novaeangliae) as a reproductive area. However, sparse information exists on the abundance, the behaviour, the distribution and the anthropogenic pressures on this species in the Caribbean and even less in the sanctuary. This thesis focuses on increasing scientific knowledge about this species’ use of a part of the Agoa Sanctuary and their interactions with human users of the MPO. Such knowledge may inform stakeholders’ (institutional and individual) decision-making towards implementation of appropriate conservation measures.
A land-based survey of more than 300 hours, in 2012 and 2013, was carried out to determine the habitat use of, and anthropogenic pressures on, a population of humpback whales frequenting the surrounding water of the Pointe-des-Châteaux peninsula in Guadeloupe. This is the first land-based survey of this species in the French West Indies and one of the first in the Caribbean. The study area of approximately 264 square kilometres is one of the most visited areas by this species in the Guadeloupe archipelago. Using a theodolite, 107 trajectories (i.e. groups of whales) were recorded, representing 137.8 hours and 699 surfacings.
Results show that the abundance was higher in March and April with a peak in the first week of April. The high proportion of calves in this population, mainly in March, suggest that the study zone is a nursing area. Overall movement patterns are not random and may possibly be dictated by the bathymetry. Furthermore, trajectories seem to converge close to the Pointe-des-Châteaux. The average movement is slow and oriented in the same direction as the dominant current to the west of the Pointe-des-Châteaux (i.e. ENE), except for mother and calf groups that swim faster in the opposite direction (i.e. WNW). Even if the anthropogenic pressure may be consided as moderate, a high proportion of surfacing is located in some of the main maritime traffic corridors. In addition, the shuttle corridor between Saint-Francois and Désirade island has the greatest relative risk of fatal collision.
A reduced speed for the shuttle corridor would lower significantly the collision risk. These findings may lead to more extensive studies to better understand the ecology of this fascinating species.
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