Computer methods for determining Mnemiopsis leidyi motility characteristics

Abstract

The paper considers capacities of common computer programs for analyzing the behavioral reactions to light of ctenophores, marine planktonic animals, under laboratory conditions. We showed that most image analysis programs do not automatically determine body contours of translucent objects, such as ctenophores. We developed a new method for determining basic motility characteristics of Mnemiopsis leidyi using ImageJ, Davinci Resolve video filters, and scripts written by the us. The developed method allows automatic calculating of such parameters as average and maximum speed, changes in direction of movement (locomotion vectors), and the percentage of time animals spend in certain regions of interest (ROI). The average speed of ctenophore movement was estimated in millimeter scale with high precision. The method is applicable for studying the behavior of various translucent marine animals. Computer scripts are available by request from the authors.

Keywords

• Mnemiopsis leidyi
• ctenophore
• migration
• motility characteristics
• image analysis tools
• ImageJ