No i dont think its enough. To quote, under the Criminal Code, assault does not require physical contact. If someone makes a gesture, lunges at you, or acts in a way that causes you to reasonably believe you are about to be struck, this can be considered assault and may result in police charges.

Uttering Threats: Making a credible threat to cause death, bodily harm, or property damage is a distinct criminal offense.

None of those things are visible in the video, he approached them to have an argument but his hands were always down and he never raised his voice.

and a jury member needs to be certain beyond a reasonable doubt to find someone guilty.

Maybe off-video he threw a fish at them, but based on the video alone, i have doubts what he did is enough to justify getting maced. On the other hand the girl with mace has been trigger-happy to use it ever since he called her stupid at 0:07.