No , it ’ s not a nudibranch ! Paul Naylor explores the multi-faceted life of the sea hare
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Portrait of a sea hare
Sea hare Aplysia punctata
No , it ’ s not a nudibranch ! Paul Naylor explores the multi-faceted life of the sea hare
I
like to think of the sea hare as the ‘ dark horse ’ of the sea slug world , like a person who seems strait-laced until you hear they have a surprising back story ! Sea hares are not nudibranchs , and while they lack the glamorous appearance of so many of that group , they have plenty of remarkable habits to intrigue us , starting with defence . Unlike the nudibranchs , they
A crab attacking this sea hare got a faceful of purple slime
have a shell but it is small , insubstantial and hidden inside their bodies , so offers them no protection . They need another way of deterring predators . This comes in the form of repellent fluids , a whitish foultasting slime and a vivid purple fluid that , when attacked by an animal such as a crab , are released to produce an unpleasantly sticky deterrent screen .
Sea hares have distinctive flap-like lobes on their back and a pair of broad head tentacles that look just like ears and give them their sea hare name . Colouration is highly variable , from brown to olive-green or dark red ; it is thought to be determined by the type of seaweed they have been eating . Another difference from the nudibranchs is that they are generally vegetarian , although they probably consume small animals stuck to the seaweed as they graze .
All sea slugs are hermaphrodites , simultaneously capable of being both male and female . The particular claim to fame of sea hares is that they often do more than fertilise each other in a pair and form a mating chain . Within it , each individual can act as a male for the one in front , and as a female for the one behind . Occasionally , the chain is a complete ring , so all of them get the full experience . This impressive
" An egg string can contain over 100,000 eggs "
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