When I was young, my mother noticed that we kids were saying "seagles" (pronounced like "eagles"), when we saw gulls. After growing up I became a nature eco-tourist and a "birder". Now it seems so strange to hear so many adults pronouncing a word that is almost the same thing that I grew out of saying as a child. Virtually all gulls are marine though some nest near fresh water during their breeding seasons. But even they frequent salt-water environments during their non-breeding seasons. Winter is a great time to see inland gulls flying along the Texas Gulf Coast. Even though these species, at certain times of the year, spend much of their time inland, I have never in my life heard anyone say "land gull". So "sea" is extraneous when referring to gulls. My birder and college-educated friends never call them anything but "gulls". There is no such thing as a "Western Seagull", "Herring Seagull", "Laughing Seagull", "Sooty Seagull", "Franklin's Seagull" or "Bonaparte's Seagull". They are all gulls. I suppose, though, that if you walked up to the average bloke and said "Take a look at that gull", he either wouldn't know what you were talking about or would have thought that you had trouble pronouncing the English word that meant a female child.
