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Published on: November 12, 2021
Algal toxins alter copepod feeding behavior.
Jiarong Hong1, Siddharth Talapatra, Joseph Katz
1Department of Mechanical Engineering, The Johns Hopkins University, Baltimore, Maryland, United States of America.
Plos One
|May 26, 2012
Summary
Copepods (Acartia tonsa) alter feeding behavior when exposed to harmful algal toxins. Neurotoxins from Karenia brevis strongly inhibit feeding, while cytotoxins from Karlodinium veneficum have less immediate impact.
Area of Science:
- Marine biology
- Ecotoxicology
- Zooplankton behavior
Background:
- Harmful algal blooms (HABs) pose ecological risks.
- Copepods are crucial grazers in marine food webs.
- Toxins from HABs can impact zooplankton feeding and survival.
Purpose of the Study:
- To quantify and compare the feeding behavior of copepods (Acartia tonsa) when exposed to nutritional prey versus toxic algae.
- To investigate the differential effects of neurotoxins (Karenia brevis) and cytotoxins (Karlodinium veneficum) on copepod feeding kinematics.
- To understand how algal toxins may disrupt predator-prey interactions and affect trophic control.
Main Methods:
- Digital holographic cinematography to record and analyze copepod feeding behavior.
- Distinguishing between 'sampling beating' and 'grazing beating' appendage modes.
- Quantifying durations and frequencies of beating modes under different dietary conditions.
Main Results:
- Acartia tonsa exhibits distinct feeding responses to nutritional prey, non-toxic algae, and toxic dinoflagellates.
- Exposure to toxic dinoflagellates significantly alters copepod feeding behavior, reducing grazing duration.
- Neurotoxins from K. brevis caused rapid diminishment of feeding, while cytotoxins from K. veneficum had less immediate impact.
Conclusions:
- Algal toxins differentially affect copepod feeding behavior, with neurotoxins showing a stronger inhibitory effect.
- These behavioral changes can influence the top-down control exerted by copepods on phytoplankton populations.
- Understanding toxin impacts is critical for predicting marine ecosystem responses to harmful algal blooms.
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