The Acti looks sweet, but I need a more "disposable" camera since it will be exposed to such a risky and harsh salt water environment. I have extensive experience with GoPro and have invented a cable system which remotely triggers some of their earlier cameras. One cool part of my project is that the IP camera's alarm I/O is able to trigger as many other GoPro cameras as I want, even one attached underwater. My seal video someone linked earlier in this thread was taken with a GoPro.
See, that's where our thoughts differ. One could go with a camera, cheap straight from China with no warranty at all or get something with a reliable warranty like ACTi or Axis so when something goes wrong, you can get it replaced, so safe for 3 years. For normal use for most people here, that may not matter, but for your high risk scenario, the value prop of a good warranty may be worth it.
It's a vandal proof PTZ, the orca can't damage it, I'm sure it's in the specs for IK10 vandal proofing as that's the highest number, sorry Nigel, no 11. In contrast, the Dahua IR PTZ are not vandal proof, a trade off for having IR. Orcas are just large vandals. What are Orca's doing by you anyway, I thought their natural habitat is SeaWorld.