In 2012 we lost Jean Jacques Peters, former engineer of Flanders Hydraulics Research (1964 till 1979) and international expert in sediment transport, river hydraulics and morphology. As a tribute to him we have created potamology, a virtual memorial archive whose aim is to preserve and disseminate his way of thinking and his morphological approach to river problems all over the world.This archive provides four modules, each with its specific information set relevant to Peters’ work. Where available and if not confidential, there will also be access to the full text. In dialogue with Peters’ family we continue to make his life’s work accessible.
Marine bioluminescence: measurement by a classical light sensor and related foraging behavior of a deep diving predator
Vacquié-Garcia, J.; Mallefet, J.; Bailleul, F.; Picard, B.; Guinet, C. (2017). Marine bioluminescence: measurement by a classical light sensor and related foraging behavior of a deep diving predator. Photochemistry and Photobiology 93(5): 1312-1319. https://hdl.handle.net/10.1111/php.12776
Bioluminescence is produced by a broad range of organisms for defense, predation or communication purposes. Southern elephant seal (SES) vision is adapted to low-intensity light with a peak sensitivity, matching the wavelength emitted by myctophid species, one of the main preys of female SES. A total of 11 satellite-tracked female SESs were equipped with a time-depth-light 3D accelerometer (TDR10-X) to assess whether bioluminescence could be used by SESs to locate their prey. Firstly, we demonstrated experimentally that the TDR10-X light sensor was sensitive enough to detect natural bioluminescence; however, we highlighted a low-distance detection of the sensor. Then, we linked the number of prey capture attempts (PCAs), assessed from accelerometer data, with the number of detected bioluminescence events. PCA was positively related to bioluminescence, which provides strong support that bioluminescence is involved in predator-prey interactions for these species. However, the limitations of the sensor did not allow us to discern whether bioluminescence (i) provided remote indication of the biological richness of the area to SES, (ii) was emitted as a mechanic reaction or (iii) was emitted as a defense mechanism in response to SES behavior.