On the subject of observing Marine wild life my partner and I attended a really great course called ”WiSE” (WIldlife SafE) at Falmouth Marine School last March.
http://www.wisescheme.org/
The Course was run by Colin Speedie from MER Consultants and covered:
The Law relating to Marine Wildlife
Observing Marine Wildlife - How to find them and how to avoid disturbance
Seals and Seabirds
Cetaceans, sharks and turtles - identification and behaviour
Simple science - data recording and photo identification
A really great day and learnt loads on how to correctly observe with out causing stress.
I would highly recommend this course to all boats users to help protect our marine heritage.
Shaggy