Feeding currents in calanoid copepods: two new hypotheses.

Area of Science:

• Marine Biology
• Zoology
• Oceanography

Background:

• Calanoid copepods are crucial marine herbivores.
• Their feeding behavior involves complex interactions with planktonic algae at the centimeter-second scale.
• Understanding these interactions is key to comprehending their evolutionary adaptations.

Purpose of the Study:

• To investigate the feeding behavior and physiological adaptations of herbivorous calanoid copepods.
• To explore the role of feeding currents and sensory perception in algae capture.
• To develop new methods for observing copepod feeding in a controlled environment.

Main Methods:

• Direct, three-dimensional observation of free-swimming calanoid copepods and algae in a 6-litre experimental vessel.
• Analysis of feeding currents, including motion, viscous, and sensory cores.
• Formulation of hypotheses based on observed feeding behaviors and body orientation.

Main Results:

• Calanoid copepods generate feeding currents to perceive and capture algae.
• A 'reactive field of awareness' defines the area from which algae can be re-routed.
• Direct observation is essential for understanding feeding strategies.

Conclusions:

• Two hypotheses were formulated: 1) Calanoid feeding currents are species- and age-specific. 2) Ambient water motion may facilitate niche separation by interfering with feeding currents.
• The study highlights the need for advanced observational techniques in marine feeding studies.
• Further research is needed to validate the proposed hypotheses regarding feeding currents and niche separation.