I consider myself a marine scientist because I am actively researching and publishing in the field of underwater acoustics.
Albeit part of this research is conducted in a lab or in a large test pool, or in fresh-water (lakes), part is also conducted in the sea, hence "marine".
But the correct definition is that I am an underwater scientist. "Marine" is quite reductive, in my opinion.
Then there is the point of defining a "scientist".
In my opinion the Wikipedia definition is almost right, albeit it gives too much weight to the "advanced degree" as a criterion for defining a scientist.
In some academic environments (UK, Germany, US) a doctorate is considered a mandatory degree for working in the scientific community.
In countries such as Italy, were the education standards were much higher, the Doctorate was unknow until 1987, when the first-generation of PhD candidates got their title: I was among them.
So for many years Italian scientists did not hold a doctorate title, simply because there were no doctorate courses here.
The normal "laurea" degree provided a comparable level of knowledge, if not better, than a PhD obtained in US or UK. Unfortunately this is not true anymore, our academic system has been severely "normalised" and realigned to the international standards (which are much lower).
In Italy people holding a "laurea" degree (which used to last 5 years in a single continuous course) are usually referred to be "doctors". Of course no one doubts that people as Fermi, Rubbia, Volterra, Montalcini, Parisi are scientists, but they have got no PhD degree.
So I would relax this requirement, many top-level scientists never got a PhD, and still impacted significantly on science and even won a Nobel prize.
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