Invited speakers: Egil Ona (Institute of Marine Research, Norway) Klas Ove Möller (University of Hamburg, Germany)
Monitoring zooplankton communities in the oceans presents important spatial sampling challenges, not the least of which is our reliance on samplers and sensors to yield precise and unbiased measures of what we cannot see directly. Traditional net samplers have limited spatial and sample-volume resolution with respect to many ecological processes under investigation. This is especially problematic given the inherent patchiness, differential avoidance, and fragility that some zooplankton display. Both acoustical and optical systems provide a means of reducing or overcoming some of these challenges.
Acoustical methods are presently used to study zooplankton in situ at scales relevant to ecologically important behaviourally- and physically-driven dynamic processes, such as predator–prey interactions, vertical migrations, and aggregation dynamics. Although acoustics is a remote-sensing technique and therefore requires direct sampling to confirm species identification, rapidly evolving processing methods for multifrequency and broadband data continue to enhance the precision and accuracy of remote species classification. Optical systems such as the VPR, ISIIS LOPC, and others are emerging as powerful tools for documenting the distribution, abundance, species identification, and behaviour of zooplankton on fine- to basin-scales, demonstrating particular advantage by their ability to image fragile taxa. Moreover, optical approaches such as the ZooScan/ZooImage are improving the rate and manner that samples are processed.
The primary aim of this session is to assemble zooplankton scientists from a wide range of disciplines to explore the advantages and limitations of acoustics and optics in zooplankton ecology. Demonstrations of the combined use of optics, acoustics and nets in a multi-sampler/sensor context are of particular interest.