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Hnízdní biologie plameňáka růžového (Phoenicopterus ruber) v zoo Ohrada / Nesting biology of the Pink Flamingo (Phoenicopterus ruber) in the zoo OhradaŠENKÝŘOVÁ, Marie January 2013 (has links)
Flamingos belong to the Phoenicopteridae family. They are occurred from India, through southern Europe to South Africa, flamingo cover Caribbean and southern half of South America at the Western Hemisphere. They consist mainly monogamous couples and their nesting is highly synchronized. They lay usually one egg, even if there are the records about laying two eggs. Incubation of the Greater flamingo (Phoenicopterus ruber) takes 26-32 days. The thesis was performed in Zoo Ohrada Hluboká nad Vltavou, where observation of nesting behavior at Greater flamingos (Phoenicopterus ruber roseus) was the main focus of observation. It was used the method of the direct observation, add a notes of zoo-keeper. Birds were recognition by color rings with a three-letter code. The main aims were the observation nesting activities which were compared at different times, between males and females and between individuals. Evaluating the parameters of the breeding to improve breeding was other aim. There were determined, that nesting activities were different among individuals, among couples and also among sex of individuals. Display of nesting activities also depended on the situation, in which individuals found, if it had an empty nest, egg or chick, or if the egg were lost and had to lay new one. It was determined, that the nesting activities of individuals varies accord the season. They are too high synchronization in the period of laying eggs and hatching chicks. Observing individuals did more non-nesting activities.
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Factors influencing Kemp's ridley sea turtle (Lepidochelys kempii) distribution in nearshore waters and implications for managementMetz, Tasha Lynn 15 November 2004 (has links)
Post-pelagic juvenile and subadult Kemp's ridley sea turtles (Lepidochelys kempii) (20-40 cm straight carapace length) utilize nearshore waters of the northwestern Gulf of Mexico as nursery or developmental feeding grounds. This study utilizes 10 years of entanglement netting data to characterize long-term abundance and distribution of Kemp's ridley sea turtles at index habitats in this region. Netting surveys were conducted during April-October 1993-2002, primarily at Sabine Pass, Texas and Calcasieu Pass, Louisiana. Additionally, this study takes an ecosystem-based approach to understanding factors influencing Kemp's ridley in-water abundance and distribution via the development of a conceptual model incorporating data on nesting dynamics, environmental conditions, prey availability, and predation pressure.
Overall monthly mean ridley catch-per-unit-effort (CPUE) peaked in the beginning of summer (April-June), probably in response to rising water temperatures and seasonal occurrence of blue crab prey. Annual mean ridley CPUE across all study areas peaked in 1994, 1997, 1999 and 2002, suggesting a 2-3 year cycle in abundance that may be related to patterns in clutch size or hatch success at the Rancho Nuevo, Mexico nesting beach. However, ridley CPUE in nearshore waters remained relatively constant or decreased slightly even as number of hatchlings released from Rancho Nuevo increased exponentially. Annual declines in Texas strandings since 1994 and subsequent increases in Florida counterparts since 1995 suggest a shift in ridley distribution from the western to eastern Gulf in recent years.
Significant declines in ridley CPUE at Sabine Pass since 1997 coincided with a concurrent reduction in blue crab size, but a similar trend was not detected at Calcasieu Pass. Kemp's ridley occurrence at study sites was not significantly related to shrimping activity/by-catch. There also were no biologically significant relationships between Kemp's ridley CPUE and abiotic factors, nor were ridleys deterred from utilizing areas frequented by bull sharks. Overall, nesting dynamics and prey availability were conceptual model components appearing to have the greatest influence on nearshore ridley occurrence.
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