Batter Runner proceeds to second with R1 on first.

[lawump]

Professional mechanics:

No signal and no verbal (a/k/a "spoken") statement given when the catch is a "can of corn". [It only takes giving a catch signal and saying "catch" once on a can-of-corn on the professional level to hear some player/coach/manager say "no ****" (or something similar) to you.]

It is okay to say, "Jim, got a catch". [Where "Jim" is your partner.]

Both umpires should be watching the ball. However, the umpire(s) who have responsibility for any runner(s) should glance at the runners. "Watch the ball, glance at the runner(s)!" I teach several clinics a year with a former instructor at one of the umpire schools and he has told me that that phrase is repeated every day for six weeks at school.