Just popping out to pick up the kids: The MALE fish who looks after his babies for weeks on end in his mouth

If you don't like being left alone with the kids, spare a thought for this very modern male fish who is left to look after its babies - in its mouth.
The Cardinal Fish is a mouthbrooder, where the males carry all the eggs in their mouth for weeks, unable even to eat until they have hatched.
Every few minutes the fish spits some of the eggs out to move them around before sucking them back in but lucky photographer Nicolas Terry was there to see some of them actually hatch.
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Thoroughly modern: The Cardinal Fish is a mouthbrooder, where the males carry all the eggs in their mouth for weeks, unable even to eat until they have hatched

Rarely seen: Every few minutes the fish spits some of the eggs out to move them around before sucking them back in but lucky photographer Nicolas Terry was there to see some of them actually hatch

Mr Terry, 51, a retired policeman, took the shots on a night dive at Mosman, New South Wales in Australia.
'Located underneath rocks the Cardinal Fish hides to hatch out its eggs and this fish was no exception,' he said.

 

'I have been taking underwater photos at the site both during the day and night and this was the first time I ever came across a Cardinal Fish with eggs ready to hatch.
'I thought to myself "what a great find" so I settled on the sand and watched this little fish.
'I saw every so often it would spit out the eggs and suck them back in and a few eggs floated off and I then saw these eggs had tails and were hatching. I was very excited to find this and be able to capture the moment.'

Ready to pop: Mr Terry, 51, a retired policeman from the UK, took the shots on a night dive at Mosman, New South Wales in Australia

Mouthbrooder: Females release an egg mass close to the chosen male after the he fertilises the eggs, he will take them into his mouth to carry them during the incubation period, until the fry are ready to hatch

Normally the female will release an egg mass close to the chosen male and after the male fertilises the eggs, he will take them into his mouth to carry them during the incubation period, until the fry are ready to hatch.
As he incubates the eggs the male Cardinal Fish will open its mouth to rotate the egg mass from time to time, to keep them clean and aerated.
At times it will partially expel the eggs before sucking them back in. It is estimated that up to 30 per cent of the eggs are accidentally eaten.

Under threat: The Cardinal Fish could be vulnerable to global warming. Hotter seas are killing off coral and higher water temperatures mean they need to breathe more - difficult when your mouth is completely full of eggs

Despite using this method of breeding for the past 50 million years, the Cardinal Fish could be vulnerable to global warming.
They tend to stay in the same place under corals, but warming seas are killing off and bleaching the coral.
On top of this, increasing water temperatures mean they need to breathe more; difficult when your mouth is completely full of eggs.