Of all the animals of prey, man is the only sociable one.
Every one of us preys upon his neighbour, and yet we herd together.
The Beggar's Opera: John Gay

Wednesday, 7 July 2010

Happy shrimp come out to play

Typical. You wait ages for a crustacean story then two come along at once. This time it's shrimps, who are, it seems, so whacked-out on Prozac they've lost their instincts for self-preservation.

'Portsmouth University researchers looked at the effect of the anti-depressant fluoxetine, also known as Prozac, on the behaviour of shrimps. The shrimps are widely found in British coastal waters, close to treatment plants where the water may be contaminated with Prozac.

The researchers found that the crustaceans, which are usually happiest when hiding under rocks or clumps of seaweed, were drawn out into the open. It is thought that just as in people, Prozac is altering levels of the brain chemical serotonin. But, while in people this lifts mood, in shrimps, it draws them towards light - and into harm's way.'

Despite the media reaction, eagle-eyed readers will have noticed that we are looking at hypothetical conclusions drawn from what was presumably a lab experiment - there's no hard evidence to back it up in the wider natural habitat, at least as yet; just a lot of 'ifs' and maybes'.

But it's a worrying business contemplating what may be pouring into the seas - even if these researchers are wrong and the shrimps are still morose and depressed, they are likely to be getting a potent cocktail including, among other things, oestrogen and caffeine (sounds like the ideal drink for hen nights in Portsmouth - perhaps they could call it 'Sex and the City?').

'Previous studies have shown that caffeine is released into our waterways after surviving the sewage treatment process. The hormones from the contraceptive Pill and HRT have been blamed for feminising fish, leading to male fish producing eggs.'

According to Marine zoologist Alex Ford, 'Effluent is concentrated in river estuaries and coastal areas, which is where shrimps and other marine life live - this means that shrimps are taking on the excreted drugs of whole towns.'

Trouble is, all that effluent provides just the sort of nutrient-rich environment shrimp and shellfish love. Seafood salad, anyone?


  1. "...this means that shrimps are taking on the excreted drugs of whole towns.'"

    Better avoid any shrimp caught near Canvey Island then, unless you want to find yourself on the run from the police in a rural area, hotly pursued by Kay Burley in a newscopter!

  2. Hadn't considered that one, JuliaM; maybe it's not the Prozac at all that's got them heading for the bright lights:

    'Hey guys, let's parteeee!'

  3. Given the plans of the barmy burghers of Brussels, I foresee a new breed of maneating killer shrimp heading to our shores (and movie screens) in due course...

  4. JuliaM, well spotted, but I rather wish you hadn't...