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21	The Whistle caller concept - Signature whistles as call-over signals for Bottlenose dolphins (Tursiops truncatus) under human care Rylander, Tilde January 2021 (has links) Dolphins use stereotyped, individually distinctive, frequency modulated whistles, referred to as signature whistles, in order to broadcast their identity. In this study, we trained six dolphins at Kolmården Zoo, Sweden, to be called over, either upon hearing their own signature whistle (SW) or upon hearing a biologically irrelevant ”trivial” sound (TS), with the aim to prove the Whistle caller concept. The Whistle caller concept is based on the fact that dolphins occasionally use other dolphins’ signature whistles in order to address specific group members and convene. Our hypotheses were that (1) dolphins call-over trained using their SW would learn the behaviour faster than dolphins trained using TSs, and (2) dolphins trained with their SW would be able to discriminate between different SWs better than dolphins trained with a TS would be at discriminating between different TSs. Three out of three dolphins were successfully call-over trained using their SW, and two out of three dolphins using their assigned TS. When discriminating between different sounds, two of the dolphins trained using their SW performed significantly better than one of the dolphins trained using a TS. However, there were large intra-group differences in the results, indicating that we cannot eliminate the possibility that these results stem from individual differences in these dolphins’ ability to learn new behaviours overall, rather than an understanding of the sounds they heard. We suggest that future studies focus on (1) male-female differences in discrimination success when applying the Whistle caller concept, (2) how the characteristics of the trivial sounds affect discrimination success, and (3) the option of calling more than one animal at a time by sending out several SWs in succession. Bottlenose dolphin Tursiops truncatus Dolphin communication bioacoustics signature whistle zoo animals animal training animal welfare the Whistle caller concept Natural Sciences Naturvetenskap Behavioral Sciences Biology Etologi Zoology Zoologi
22	Diving deeper into the dolphin's Umwelt : acoustic, gustatory, olfactory and magnetic perception Kremers, Dorothee 11 December 2013 (has links) (PDF) The Umwelt concept of Jakob von Uexküll considers animals as subjects that inhabit their own subjective universe which is determined by the animal's sensory perception and cognitive abilities. Dolphins present an interesting species to investigate its Umwelt because cetaceans underwent a drastic change in lifestyle in the course of evolution because these mammals returned from a terrestrial life back into the water. Although bottlenose dolphins are intensively studied there are still many knowledge gaps. Here we studied some aspects of the dolphins' Umwelt by asking: (1) how their nocturnal acoustic Umwelt is arranged; (2) what the production of vocal copies can tell us about the dolphins' perception of their environment; (3) whether they are able to perceive tastes (4) or odours; (5) whether they are sensitive to magnetic stimuli. We found that the dolphins' nocturnal Umwelt was characterized by a temporally patterned vocal activity that also included vocal copies of sounds that the dolphins had heard during the day. This is a striking separation between auditory memory formation and vocal copy production and the copies might be a vocally expressed nocturnal rehearsal of day events. Thus, vocalizations can serve as possible indicators of events or objects that are meaningful to the dolphins. Regarding dolphins' perceptive abilities, we found that they were sensitive to both gustatory and olfactory food-related stimuli. They might use this ability to locate and/or evaluate prey. Further, dolphins responded to a magnetic stimulus, suggesting that they are magnetosensitive, what could be useful for navigation. So far, chemo- and magnetoreception have not been considered seriously as potentially functional in dolphins. The results obtained during this thesis fill some of the gaps that still exist in the knowledge of the dolphin's Umwelt and therefore contribute to a better understanding of this species. Moreover, they illustrate that even already intensively studied species may still hold important facets of their biology to reveal and that research should broaden the view and remain unbiased when studying a topic. [SDV:BA] Life Sciences/Animal biology Perception Audition Sense of taste Sense of smell Magnetoreception Tursiops truncatus Cetaceans
23	The Social Structure and Mating Strategies of Bottlenose Dolphins (Tursiops truncatus) in the St. Johns River Ermak, Jessica Lea 01 January 2014 (has links) Across populations, bottlenose dolphins (Tursiops sp.) exhibit a fission-fusion pattern of associations, in which group size and composition change fluidly throughout the day. Beneath this seemingly ephemeral social structure, considerable variation exists across study sites. While females typically have moderate bonds with one another within a large social network, male-male bonds are variable, though males typically take one of two strategies; some males encounter females individually for opportunities to breed while others cooperate within a first-order alliance to collectively herd females. In addition, multi-tiered alliances in which two first-order alliances cooperate to defend or assist in the theft of a female have been documented within Shark Bay, Australia. However, these patterns do not apply to all study sites, as intersexual bonds are strong within several bottlenose dolphin populations. Given the variation in the presence and complexity of male alliances, greater documentation of social structure and male mating strategies across study sites is needed to draw conclusions as to the ultimate factors behind alliance formation. As such, chapter one documents the inclusion of a new study site in the St. Johns River (SJR) in Northeast Florida where males form first and second-order alliances. In addition, variables from the SJR are included within a meta-analysis in chapter two, the first systematic examination of what variables correlate with alliance presence and complexity, with the conclusion that male-male competition best describes the patterns seen in male alliance formation. Chapter three builds upon this conclusion by examining seasonal trends in tooth rake marks, a proxy for aggression, across the sexes and males of two different mating strategies, ultimately highlighting the potential for non-reproductive aggression. Together, this work provides greater insight as to the social structure and mating patterns of bottlenose dolphins, as well as to the ecological pressures that result in complex sociality. Thesis University of North Florida UNF social structure half-weight index male alliance tooth rake mark Tursiops truncatus Biology Marine Biology
24	Reproductive Biology of the Female Bottlenose Dolphin (Tursiops Truncatus) Muraco, Holley Stone 11 December 2015 (has links) The goal of this long-term study was to better understand the reproductive biology of the female bottlenose dolphin (Tursiops truncatus) and provide a hypothesis for how dolphins may communicate reproductive readiness to one another. Utilizing conditioned dolphins in aquaria, this dissertation examined several previously unknown aspects of dolphin reproduction, including ovarian follicular dynamics during the luteinizing hormone surge, urinary prolactin levels, estrus behavior, vaginal fluid arboriform arrangement, in-situ vaginal and cervical anatomy during estrus, reversed-phase high-performance liquid chromatography (RP-HPLC) of urine samples to identify proteins and peptides that may be used in chemical communication, and a review and anatomical analysis of dolphin vibrassal crypts. The diffusely seasonal dolphin estrous cycle is not controlled by photoperiod and has a 10-day follicular and 20-day luteal phase. A brief ovulatory LH surge is followed by ovulation within 48 hours. An ethogram of 20 reproductive behaviors was developed, and all occurrences of reproductive behavior were analyzed during conceptive estrous cycles. A novel form of standing heat estrus, termed immobility, was observed, and estrus dolphins displayed genital nuzzling, active and passive mounting with other females, and an increase of standing heat intensity as LH levels rose. Prolactin plays a role in pregnancy maintenance, mammary development, allo-mothering behavior, lactation, and lactational anestrus. Dolphins are similar to sows where weaning causes a return to estrus, and in the boar effect, where days to ovulation are shortened in the presence of a mature male. Dolphin vaginal fluid showed crystallization arrangements with large open mesh patterns, conducive to sperm transport, during the estrogenic follicular phase, and closed mesh during the luteal phase. RP-HPLC analysis revealed that urine contained large amounts of peptides and proteins with peaks that change throughout the estrous cycle and with changes in social grouping. Remnant vibrissae from dolphin follicular crypts were sectioned, and it was hypothesized that trigeminal nerve endings could act similarly to those found in the nasal mucosa of terrestrial species and respond to chemical stimuli. This study provides new data to better understand the reproductive biology of a holaquatic mammal. neonate nursing mammary gland follicles cryopreservation cervix uterus ovaries anatomy crypts vibrassae lutenizing hormone progesterone estrogen testosterone semen urine biology tursiops truncatus bottlenose dolphin pheromone prolactin endocrinology ultrasound estrus ovulation behavior reproduction dolphin
25	Development and testing of mycoinsecticides based on submerged spores and aerial conidia of the entomopathogenic fungi Beauveria bassiana and Metarhizium anisopliae (Deuteromycotina: Hyphomycetes) for control of locusts, grasshoppers and storage pests / Mycoinsecticides for pest control / Biologische Schädlingsbekämpfung / Mykoinsektiziden für Schädlingsbekämpfung Kassa, Adane 14 July 2003 (has links) No description available. 630 Landwirtschaft Veterinärmedizin Agricultural Sciences Biologische Schädlingsbekämpfung Lagerschädlinge Sitophilus zeamais Prostephanus truncatus Formulierung Applikation Massenproduktion Submerskonidien Submerssporen Luftkonidien gefriertrocken sprühtrocken Metarhizium anisopliae Beauveria bassiana Mykoinsektiziden Formulierung Pulverformulierungen Heuschreckenarten Locusta migratoria Hieroglyphus daganensis Cryptocatantops haemorrhoidalis Biological control entomopathogenic fungi submerged spore submerged conidia aerial conidia Beauveria bassiana Metarhizium anisopliae production formulation mycoinsecticides locusts grasshoppers Locusta migratoria Hieroglyphus daganensis Cryptocatantops haemorrhoidalis Sitophilus zeamais Prostephanus truncatus storage pest spray-drying Freeze-drying dustable powder formulation 83.66 (Agrarwirtschaft) YEK 400 Schädlingsbekämpfung

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