What’s the difference between a nudibranch and a sea slug?

Until I read a gorgeous new book on nudibranchs by Tim Nicholson I didn’t think there was a difference. Not so. All nudibranchs are sea slugs but not all sea slugs are nudibranchs.

Sea slug is the common name for any marine gastropod without a visible shell (slug-like rather than the snail-like) including sea hares & nudibranchs. A nudibranch is 1 type of gastropod among many.

Book review is at https://news.scubatravel.co.uk/whats-the-difference-between-a-nudibranch-and-a-sea-slug.html

Just discovered the beautiful drawings of Jessica Eggers jessieggers.com #scubadiving #art #oceans

Just finished Helen Scales excellent book Spirals in Time. I'm now desperate to see the Pinna nobilis giant mussel sea silk weavings in Sardinia #scubadiving #molluscs #marinebiology #ocean

On Nov14, governments are meeting to consider placing international trade restrictions on over 50 vulnerable species of sharks at CITES. PADI are asking you to sign a letter urging your government to vote yes to protect the sharks.

https://e-activist.com/page/114810/petition/1

Two of my old friend Tim Nicholson's photos feature in new issue of #isleofman stamps (#nudibranch and squat lobster) #underwaterphotography

A boring sponge

Not just any old sponge that is a bit tedious, but the Red Boring Sponge.

It's called the boring sponge as it drills into coral and sea shells. The sponge breaks down dead and diseased (and sometimes live) coral.

In "normal" conditions they play an important part in the reef, recycling calcium carbonate. But if the coral is struggling due to high temperatures or pollution, the boring sponges can erode the reef faster than the corals can replace it. #scubadiving

Acropora coral amongst xenia in the Red Sea

If you've dived in the Red Sea you will have seen pulsating soft coral repetitively "grabbing" at the water. They are so common that we take them for granted. But only one family of coral does this - the Xeniidae.

#scubadiving #underwaterphoto
#coral

Love these cartoons by Christian Talbot and Sophie Hodge