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The Fine-Scale Habitat Use Of Risso’S Dolphins Off Bardsey Island, Cardigan Bay (Uk), Marijke N. De Boer, Sonja Eisfeld, Mark P. Simmonds
The Fine-Scale Habitat Use Of Risso’S Dolphins Off Bardsey Island, Cardigan Bay (Uk), Marijke N. De Boer, Sonja Eisfeld, Mark P. Simmonds
Mark P. Simmonds, OBE
The main objectives of this study were (1) to estimate the population size of Risso’s dolphins off Bardsey Island using mark-recapture techniques (De Boer et al., 2013); and (2) to study habitat-use in relation to fine-scale oceanographic features. This work provides preliminary information on the habitat-use of Risso’s dolphins and will benefit future studies, along with the development of effective conservation measures for this species throughout the region.
Photo-Identification Methods Reveal Seasonal And Long-Term Site-Fidelity Of Risso’S Dolphins (Grampus Griseus) In Shallow Waters (Cardigan Bay, Wales), Marijke N. De Boer, Josephine Clark, Mardik F. Leopold, Mark P. Simmonds, Peter J.H. Reijnders
Photo-Identification Methods Reveal Seasonal And Long-Term Site-Fidelity Of Risso’S Dolphins (Grampus Griseus) In Shallow Waters (Cardigan Bay, Wales), Marijke N. De Boer, Josephine Clark, Mardik F. Leopold, Mark P. Simmonds, Peter J.H. Reijnders
Mark P. Simmonds, OBE
A photo-identification study on Risso’s dolphins was carried out off Bardsey Island in Wales (July to September, 1997-2007). Their local abundance was estimated using two different analytical techniques: 1) mark-recapture of well-marked dolphins using a “closed-population” model; and 2) a census technique based on the total number of iden-tified individual dolphins sighted over the study period. The mark-recapture estimates of 121 (left sides; 64 - 178, 95% CI; CV 0.24) and 145 dolphins (right sides; 78 - 213, 95% CI; CV 0.24) closely matched the census technique estimates (population size of 90 - 151). It was found that the dolphins …
Interactions Between Short-Beaked Common Dolphin (Delphinus Delphis) And The Winter Pelagic Pair-Trawl Fishery Ff Southwest England (Uk), Marijke N. De Boer, James T. Saulino, Mardik F. Leopold, Peter J.H. Reijnders, Mark P. Simmonds
Interactions Between Short-Beaked Common Dolphin (Delphinus Delphis) And The Winter Pelagic Pair-Trawl Fishery Ff Southwest England (Uk), Marijke N. De Boer, James T. Saulino, Mardik F. Leopold, Peter J.H. Reijnders, Mark P. Simmonds
Mark P. Simmonds, OBE
During offshore and onshore studies (2004 to 2009), the interactions between pair-trawls and short-beaked common dolphins (Delphinus delphis) were studied to better understand the impact of bycatch. A ‘hotspot’ area where pair-trawls overlapped with high dolphin abundance was identified. We made comparisons between boat-based data collected in absence and presence of pair-trawlers. The relative abundance and group-size of dolphins was significantly higher in the presence of pair-trawlers. Dolphins were observed associating with towing and hauling procedures. Significantly, more carcasses occurred in areas with hauling-activity than those without. Body-temperatures obtained from carcasses found near operating pair-trawlers indicated that bycatch mostly occurred …
The Reproduction And Ecology Of Hypericum Edisonianum: An Endangered Florida Endemic, Warren G. Abrahamson Ii, Sam P. Vander Kloet
The Reproduction And Ecology Of Hypericum Edisonianum: An Endangered Florida Endemic, Warren G. Abrahamson Ii, Sam P. Vander Kloet
Warren G. Abrahamson, II
The reproduction and ecology of the narrow endemic and Florida endangered shrub Hypericum edisonianum (Edison’s St. John's Wort) was investigated through field and greenhouse studies. Hypericum edisonianum exhibits a number of traits common to rare and geographically limited plant species including heavy reliance on clonal propagation to maintain local stands; passive seed dispersal resulting in a near-parent seed shadow; limited numbers of genetically unique individuals in its isolated seasonal-pond habitat; and likely self-incompatibility. In the field study, most flowers were produced by a small subset of the monitored ramets. Indeed, three ramets belonging to a single genetic individual accounted for …