Potential Applications of Low Altitude Remote Sensing for Monitoring Jellyfish

Abstract

Jellyfish (cnidarian) are conspicuous in many marine ecosystems when in bloom. Despite their importance for the ecosystem structure and function, very few sampling programs are dedicated to sample jellyfish because they are patchily distributed and easily clogged plankton net. Although satellite remote sensing is an excellent observing tool for many phenomena in the ocean, their uses for monitoring jellyfish are not possible due to the coarse spatial resolutions. Hence, we developed the low altitude remote sensing platform to detect jellyfish in high resolutions, which allow us to monitor not only horizontal, but also vertical migration of them. Using low altitude remote sensing platform,we measured the jellyfish from the pier at the Chesapeake Biological Laboratory in Chesapeake Bay. The patterns observed included discrete patches, in rows that were aligned with waves that propagated from deeper regions, and aggregation around physical objects. The corresponding areas of exposed jellyfish on the sea surface were <TEX>$0.1{\times}10^4pixel^2$</TEX>, <TEX>$0.3{\times}10^4pixel^2$</TEX>, and <TEX>$2.75{\times}10^4pixel^2$</TEX>, respectively. Thus, the research result suggested that the migration of the jellyfish was related to the physical forcing in the sea surface.