One of the risks in diving is buddy separation, and a more serious risk is buddy abandonment. Whether you're diving locally around Vancouver or internationally anywhere in the world, you'd be wise to expect that if you're buddied with a stranger or if you're just one of several divers following a professional dive leader, there's a very real probability that if you experience a problem of some kind, you'll be abandoned by your buddy or group leader just when you need help the most.
As a rule of thumb, you should never consent to buddy with someone that you've never been diving with before.
But don't take my word for it.....here's an article below from Diver Magazine that tells a typical abandonment story.
One of the most frequent causes for buddy separation is the loss of buoyancy control. One diver rises in the water column, out of sight. This happens to me all the time. I watch the student rise out of sight, I wait, hovering in the area where we were separated, and most of the time they regain control and descend back down.
A good rule of thumb is that the diver who loses buoyancy control has the responsibility to regain control and drop back down.
If the diver goes all the way to the surface, then the rule is to stay there and establish positive buoyancy. A responsible buddy will meet you there in a minute or two.
Another common way that divers become separated when swimming side by side is one is swimming faster than the other. The rule there is that the faster swimmer must slow their pace, because the slower swimmer would become overexerted trying to keep up.
A third way that divers get separated is that each is following a different subject of interest rather than a single shared experience. They just swim apart in different directions.
All of these situations can happen on a single dive.
Incidentally, when I was an unskilled novice diver, I was abandoned underwater by my buddies (strangers) in Hanauma Bay, Hawaii, when my low pressure inflator hose started to free flow into my BCD at a depth of 40 feet on the first dive of the day. I didn't know what to do and held onto a coral head until I lost my grip and rocketed to the surface. My buddies just swam away. (These days, I'd disconnect the hose and continue the dive, inflating the BCD orally as needed. And I'd communicate this situation to my buddy). Luckily I didn't end up in the hospital, but I surfaced down-current from the boat and needed to be rescued. Back on the boat, the captain blamed me for leaving my buddies and having to get in the water to rescue me. He said there would be no refund (I hadn't asked for one!), even though the BCD continually reinflated itself to near bursting as it sat on the dive deck. He finally acknowledged the gear malfunction and encouraged me to take another scuba unit and reenter the water alone, because there would be no refund. Despite my lack of skill and experience with diving alone, I put on another BCD, re-entered the water, descended directly into the middle of a large school of small fish... and had my first ever face-to-teeth encounter with a feeding shark. I don't remember my fins touching the the ladder as I breached the surface and launched myself onto the boat deck. The captain looked at me like I was from another planet and insisted that there were no sharks in these waters. At this point he insisted that I was not going back into the water for the second dive and I wasn't getting a refund. And I replied... not with your equipment I'm not, not with these buddies and not off your boat. When my assigned buddies finally returned to the boat, their excuse for leaving me was that they assumed I wanted to dive alone. This is the reality when diving with strangers at tourist dive sites.
I've witnessed buddy abandonment many, many times as an instructor while teaching group Open Water courses and leading group dives.
I can't tell you how many times I've signalled a diver to ask where their buddy is only to get a shrug of the shoulders in response or a finger pointed toward the surface. But one day, when leading a group of certified divers who were all strangers, on the descent at a site with a steep slope, the response was a finger pointed downwards. I signalled everyone to resurface and emptied my BCD to chase after the missing diver, a middle aged woman who hadn't been diving in a couple of years. I caught up to her at 90 feet as she was tumbling and rolling down the slope. I stopped her tumble and found that the low pressure inflator hose was disconnected so she was unable to power inflate the BCD. (This failure to properly set up the scuba unit ought to have been discovered during the buddy pre-dive safety check). I reconnected the hose and we made our way safely back to the surface. Whew. She was terribly shaken up, but otherwise ok. And I set a policy to always personally double check everyone's gear before every dive.
Novice and inexperienced divers often don't know what to do when a problem suddenly happens, so I emphasize the development of buddy skills in the courses I teach. Very few certified divers have the skills, knowledge and capacity to properly plan a dive or help another diver in trouble. Fewer than 1 diver in 100 is trained in rescue skills. So even if that assigned buddy doesn't abandon you, he or she might not be able to help you. Stick with the professional dive leader/Divemaster until you've evaluated a potential buddy's skills.
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