It's a High Seas "feature". The ~1_val~ bit is customizable by the server. Hybrid doesn't send any value for ~1_val~ though, it just appends the "a fish" text to the line (the way old clients wanted it). That's why it shows up.
It can and likely will be fixed server-side soon, but you could alter your client localization files (Cliloc.enu) with
UOFiddler, for example, and remove ~1_val~ if it really bothers you. The cliloc entry number is 1008124. (1008125 was changed too.)
Note that modifying the Cliloc.enu file will prevent official client patches from modifying it. It's wise to keep a back-up of the original file.