DAY 10 – MARCH FOCUS ON NORFOLK ISLAND’S REEF

Today’s focus on Norfolk Island’s reef is a photo essay. This series of photographs demonstrates how disease affects a coral bommie by gradually killing the coral and creating an environment that allows algae to gain a foothold and to eventually take over.

I first photographed this montipora coral bommie in January 2022 when I first saw the unmistakeable signs of white syndrome on one side. I have returned regularly to record the disease as it has spread, quickly at first, but then more gradually, until a few days ago when I took the last photograph in the series (below) to show you what it looks like now, one year on. Dead coral is overgrown with a luxuriant algal growth, leaving no toehold for coral recruitment (coral babies) on the dead substrate.

The new disease is bright white, but as algae takes over it gradually merges into the brown, as you can see in the series.

To be able to see these things happening, you need to be in the water over an extended period of time, looking at the same things and photographing them, time and time again. Recording these events is the only way to combat ‘shifting baseline syndrome’, a phenomenon that I mentioned in my introduction to this series: The camera doesn’t lie – looking back over three years of observations.

Coral reef researcher Professor Callum Roberts from the University of Exeter in the UK often talks about shifting baseline syndrome, saying, ‘[it] renders each new generation blind to past losses, setting their personal baseline of normality by what they first find.’

In other words, if you were new to our reef and swam past the bommie today, you would probably not give it a second glance.

If we retain the status quo with our water quality – as in allowing high levels of nutrients into our overland waterways and groundwater streams – this kind of transition is going to keep happening again and again. However, if we grasp the nettle and get serious about how we look after our water – for example, by examining everything we use in or near our water systems, whether it is to wash our hair and clean our toilets, what we spray on and feed our plants, what animals we allow near our waterways, how we dispose of our waste, and how we maintain our septic systems – then conditions may improve leading to a reduction in algal growth. This would then allow space for new baby corals (planulae) to settle and start growing, thereby regenerating the reef.

We need to decide how much our reef means to us.