The authors of a new study published in the Proceedings of the Royal Society B, have found that tiny crustaceans engage in risky behaviors when under the influence of a particular type of toxic algae.
These minuscule crustaceans, called copepods, are about 1 to 2 mm in length and are widespread in aquatic ecosystems worldwide. When copepods consume the toxic algae known as Alexandrium fundyense, their behavior changes dramatically. The copepods in the study did not die from consuming the toxic algae, in fact they reproduced, but they appeared to become inebriated.
The authors of the study initially expected the copepods to swim at a slower pace, but the opposite happened. The copepods increased the speed at which they swam and their swimming path became predictable. Because they swam in such predictable patterns, such as straight lines, they increased their risk of predation by 25 to 56 percent.
“First, they have a higher probability of encountering predators simply because they are covering more ‘new ground,'” lead author Rachel Lasley-Rasher told Discovery News. Swimming fast also meant that the copepods would likely create more disturbance in the water which in turn could attract potential predators, according to National Geographic.
Alexandrium fundyense is an algae popularly associated with the harmful algal blooms (HABs) known as red tide.
Copepods are a critical link within aquatic food webs as they provide sustenance to animals higher in the food chain. Alexandrium fundyense is an algae popularly associated with the harmful algal blooms (HABs) known as red tide.
Lasley-Rasher expressed concern over the increased predation of the copepods under the influence of toxic algae. If too many of the copepods were to be eaten by fish, or shrimp, there would not be enough of them to keep the algae in check, Lasley-Rasher told National Geographic. Another concern was that the toxins from the algae could bioaccumulate in the bodies of animals that fed on the copepods. Toxic algae is poisonous and can kill marine animals.