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The Influence Of Topographic And Dynamic Cyclic Variables On The Distribution Of Small Cetaceans In A Shallow Coastal System, Marijke N. De Boer, Mark P. Simmonds, Peter J.H. Reijnders, Geert Aarts
The Influence Of Topographic And Dynamic Cyclic Variables On The Distribution Of Small Cetaceans In A Shallow Coastal System, Marijke N. De Boer, Mark P. Simmonds, Peter J.H. Reijnders, Geert Aarts
Mark P. Simmonds, OBE
The influence of topographic and temporal variables on cetacean distribution at a fine-scale is still poorly understood. To study the spatial and temporal distribution of harbour porpoise Phocoena phocoena and the poorly known Risso’s dolphin Grampus griseus we carried out land-based observations from Bardsey Island (Wales, UK) in summer (2001–2007). Using Kernel analysis and Generalized Additive Models it was shown that porpoises and Risso’s appeared to be linked to topographic and dynamic cyclic variables with both species using different core areas (dolphins to the West and porpoises to the East off Bardsey). Depth, slope and aspect and a low variation …
The Effects Of Temperature And Daylength On The Rosa Polyphenism In The Buckeye Butterfly, Precis Coenia (Lepidoptera: Nymphalidae), Kelly C. Smith
The Effects Of Temperature And Daylength On The Rosa Polyphenism In The Buckeye Butterfly, Precis Coenia (Lepidoptera: Nymphalidae), Kelly C. Smith
Kelly C Smith
In North Carolina, Precis coenia that emerge during the Summer months exhibit a ventral hindwing (VHW) with well-defined reddish-brown and brown pattern elements on a light tan background. During late Summer and early Fall, however, individuals begin to appear with poorly defined or obscured pattern elements on a dark reddish-brown background. The present study shows that the Fall (rosa) color morph can be induced by either low rearing temperatures or short daylengths. The effect of such conditions seems to be cumulative throughout the larval life, although animals are much more sensitive during the last 24 hours of larval life and …