Nigel-Have look here:
The changes are supposed to come in on 2 January, so they will affect you.
I have written too.
The issue, as I see it, is that the proposals do not address the actual problem, namely high-speed motorized boat traffic.
Instead, they crowd more people into a smaller area for less time. Any manatees that are in the publicly accessed area will be mobbed!
Photographically, the restriction on early morning and late afternoon is the biggest issue. Strobes and flashes are probably a smaller problem photographically, although I also note that in the entire proposal document there is no scientific justification for restricting their use. As is so often the case, wildlife managers are going on a "gut" instinct that flashes are in some way harmful, rather than any properly researched argument.
In order for there to be continued positive manatee-human interactions, there needs to be robust enforcement, not restrictions.
The address to email your concerns to is : firstname.lastname@example.org