First thing that hits me is fish. Albeit a very agressive "attacking" sort of fish. I used to have a shark website as part of my portfolio, and we had some t-shirts made up that were not a million miles away from that sort of image!
I guess the point I'm making, is that there's no immediate association here. There may be a few
SEO practitioners that are 'sharks', but that's where the comparison ends, for me at least.
If you did want to stick with the piranha, why not change the scale? Presently, he's a bit on the small side, why not have him gobbling up the text to his right? (as freshdames suggests)
You might also try increasing the slant on the italics for extra drama!
Good luck!
Paul