Link
clip, not the complete show.
Apparently the Orca rammed the 3 meter white shark, then held it upside down until it died, then ate only its liver.
The film went on to explain what exactly was happening , and how the Orcas hunt rays and sharks with this specialist technique, a culture developed by a particular Pod, and what is happening to the Elasmos to make them so vulnerable.
Experiments and film in the docu show that most of not all Marine sharks and Rays are subject to Tonic immobility. If you turn them upside down they become comatose. Something happens in their brains. If they remain that way too long they can die. Turn them back upright and they immediately normalize. When they are comatose they don't need any anesthetic even for surgical proceedures (this was shown on a 2 meter long Lemon shark WOW!)
Potamotrygon (etc) are also prone to this....or are they? Is it to the same degree?
I have tube fed large Tiger and other Pots. in the past. They seemed to go catatonic when i turned them upside down, completely stopped thrashing their tails and became quite still.
When importing direct sometimes a ray would arrive dead and upside down.
Is this response enough to make MS222 etc unnecessary when treating your rays for something way that requires them to be still?
What are your experiences or thoughts on this?
