I spend between 2 and 6 hours of each day in the water. By now my wetsuit has become my second skin. So, you might be asking yourself “What the heck does she do during all that time underwater?!” The answer is SCIENCE!
There are a few key things we do in the water, depending on our schedule. Most of our time is spent making behavioral observations on various species of fishes – namely herbivores of the surgeonfish/tang and parrot fish families. We pick out a fish, start our timer, follow it around for 3-5 minutes, and count how many bites of algae (or whatever else…) it takes during that time. We also identify the functional group (turf, macroalgae, cyanobacteria, etc.) and genus of the alga, to the best of our ability – easy, right? Not as easy as it sounds! I never thought counting could be so difficult.
First problem: Fish eat really fast! Some of the species we study take as many as 100 bites per minute! Look away for even just one second and you’ve missed a significant number of bites.
Second problem: Fish are indecisive and have short attention spans. Ok, I’m anthropomorphizing a bit, but seriously – one second they’re grazing over the sand, the next they’re on a turf-covered rock, and then they’re back on the sand again… and then they hide under a big head of Porites coral. This means memorizing multiple numbers of bites for different types of substrate and keeping them straight without losing your place or confusing them with each other. As before, look away for a second and the fish might not be there when you get back.
Third problem: Some fish like to travel in schools – and they all look the same. Once again, look away, and you’re trying to find one fish in an army of clones.
a school of brown tangs (Acanthurus nigrofuscus)
Fourth problem: Fish get scared… and hide. I can’t say I blame them. Think about what a scuba diver looks like from a fish’s perspective – I’d hide too if a massive floating mysterious creature with lots of hoses and equipment was coming at me making loud Darth Vader noises and emitting a cloud of bubbles! It takes a certain finess to stalk a fish and figure out what it’s eating from a distance.
Fifth problem: Counting for 2 hours straight is monotonous and repetitive. It’s very easy to fall into a “rhythm” and start counting seconds instead of actual bites. It’s also very easy to get halfway through an observation and go… “Wait… was I on 45 or 55?” or “…10, 11, 12, 1, 2, 3, 4 – Wait… crap! Those are hours on a clock…” That second example might be a personal problem… I’ll look into it.
I’m sure you get my point. Counting has never been more complicated.
Observations stop around 4, when the fish start spawning
When we’re not making behavioral observations, we’re conducting fish surveys (counting the number of each type of species over a given area) or collecting data from Emily’s cage experiments.
Sometimes at the end of our dives we just need a break. That’s when we find time to hang out with the locals.
Meet Rocket Girl, a local hawksbill turtle at Kahekili
A pin cushion sea star we found in one of the cages
Major props and photo cred to my mentor/dive buddy, Emily! She was the photographer for most of the photos in this post.
Emily and myself at sunset, after a long day of diving