The water has gone green. Happens occasionally. The sea in Port St Charles, Barbados turns an emerald colour from its normal blue. It’s still quite clear. Just eerie.

Didn’t stop Jack – he went diving to hang out with his new best friends under Quest – the moray eels. There are loads of them. Some are cream and blue with spots, others darker brown. They all hang out with their heads poking out and their bodies wrapped up behind them. Jack takes them blue runner fish heads to eat. They’re the remains of the fish he catches at sunset.

Some of the eels are too small to swallow the poor fish heads, though they give it a good go. They tend to guard their prize for a while, and then rather sheepishly skulk away into a different hole. Jack waits for the eel to leave, picks up the head and offers it to another moray.

The big ones are large enough to swallow them, though they clearly needs some digestion afterwards. There’s a big bump in their bodies. Some have to lie down for a while. One moray came straight out of its hole and swam around us the other day after swallowing its meal. The eel was beautiful, undulating its long body under a proud blue mohawk. Saying that – it was unnerving. The green water added to the strange effect.

The eel had a right expedition. We followed it as it swam from rock to coral outcrop. It was only towards the end I realised the eel was likely playing with us. Eels are known, despite their bared-teeth fang look, to be playful. Some divers compare their behaviour to dogs. There are long-standing reports of eels being affectionate with humans. Even recognising individual divers. Of course, there are also reports of eels biting your extremities off. Not so dissimilar to dogs.

Our own experience of interacting carefully with morays – is of the former. We hope to keep it that way. To be honest, I haven’t seen a single moray being unreasonably aggressive. I haven’t stuck my finger in its mouth either though.

Back to the water. Perhaps a phytoplankton bloom turned it green. This greening event has happened a few times now – and it usually heralds the arrival of the jellies. Then, a week or so later, the green water goes back to blue.

I took a sample of sea water and looked at it under the microscope. The microscope was one of the things snuck onto Quest as ‘technical ballast’ before we left. Lives in the wine chest. Definitely not used enough.

I had a look to see if there were plankton worth seeing in the water column. Got excited about some silica-type strands too – until I realised they were scratches on the microscope slide. Hmm. Definitely rusty.

Meanwhile, Jack took some more fish heads down. Off to see his mates. The Morays.