Bacteria Rivers in the Salt Water Biome

[DonSchaeffer]

https://youtu.be/Trk8IlEC6p4

[Bruce Taylor]

I think you've recorded part of a bacterial swarm ring, a phenomenon we often see on slides. The conventional explanation is that chemical gradients form under the coverslips (differences in levels of dissolved gases, for instance), and the bacteria congregate--by aerotaxis, or chemotaxis--in the zones that are favorable to their particular requirements. Here's another record of the phenomenon from one of my old videos: https://www.youtube.com/watch?v=Q7Kf-QahX6A

[75RR]

Here's another record of the phenomenon from one of my old videos: https://www.youtube.com/watch?v=Q7Kf-QahX6A

Was just wondering where the predators were - to take advantage of this 'bacterial shoaling' when they appeared. So all was as it should be ...

[Bruce Taylor]

Here's another record of the phenomenon from one of my old videos: https://www.youtube.com/watch?v=Q7Kf-QahX6A

Was just wondering where the predators were - to take advantage of this 'bacterial shoaling' when they appeared. So all was as it should be ...

Yup. At about the 30 second mark, we see some little litostomes (probably Acineria uncinata) browsing at the edge of the ring. You'll sometimes see larger bacterivores plunging through such swarms, like whales scooping up krill.

[DonSchaeffer]

That is a really interesting series of responses, very valuable to me. Thanks.