Re: Inking in Aplysia

June 26, 2002
From: Dr.Stephen R Hoskins

Dear Bill,
Concerning my message about inking in Aplysia, here is a reference I have just found.

• Nolen, T.G. & Johnson, P.M. (2001) Defensive inking in Aplysia spp: Multiple episodes of ink secretion and the adaptive use of a limited chemical resource The Journal of Experimental Biology, 204: 1257–1268


Hoskins, S.R., 2002 (Jun 26) Re: Inking in Aplysia. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from

Thanks Stephen,
I had a look at this paper. It recounts some pretty horrifying lab experiments where the Sea Hares are suspended on hooks and 'stimulated' in various ways to show that inking is not necessarily an all or nothing event - that is the ink gland is not always completely emptied each time. This they suggest means the Sea Hare is not completely defenseless if 'attacked' before it can replenish its ink supplies. The authors refer to earlier work they have done suggesting that the ink is a defence against lobster and large sea anemone attack. I will have to check these references out, but what puzzles me is whether lobsters and sea anemones can be considered important predators or even potential important predators of sea hares. I am still to be convinced that inking is a real defence behaviour in Sea Hares and not just a form of incontinence brought about by extreme stress.
Bill Rudman

Rudman, W.B., 2002 (Jun 26). Comment on Re: Inking in Aplysia by Dr.Stephen R Hoskins. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from


Ink glands

Related messages

  1. Is Sea Hare ink poisonous to fish?
    From: Nicole Chilson, January 15, 2007
  2. How to make dye from the Sea Hare ink.
    From: Ralph Bowen, August 3, 2006
  3. Dolabrifera dolabrifera - Dissection diagram for ink gland?
    From: Kathryn Clark, June 17, 2006
  4. Aplysia californica - ink
    From: Malvina Papanastasiou, March 23, 2006
  5. Separating Ink Components of Aplysia dactylometa?
    From: Scott Schwartz, March 6, 2006
  6. Re: Inking in Aplysia
    From: lorrie creach, October 24, 2005
  7. Pharmacokinetic peptides in Dolabella auricularia
    From: Sallie Dugan, July 29, 2004
  8. Sea Hare color purple
    From: Patricia, October 24, 2003
  9. Allergic to Sea Hare Ink?
    From: Martin Masters, August 13, 2003
  10. Do frightened Aplysia secrete ink involuntarily?
    From: Dr. Stephen Hoskins, September 24, 2002
  11. Re: Inking in Aplysia
    From: Edwin Cruz-Rivera, June 27, 2002
  12. Re: Effect of secretions on Aplysia
    From: Cathryn Clarke, June 26, 2002
  13. Effect of secretions on Aplysia
    From: Stephen Hoskins, June 22, 2002
  14. Ink Glands in Octopus and Sea Hares
    From: Nadine Schoene, March 21, 2002
  15. Sea Hares and Inking
    From: Melanie, March 22, 2001
  16. Sea Hare Self Defense
    From: Tina Paget, February 21, 2001
  17. Siphon Withdrawal Reflex in Sea Hares
    From: Steve Potts, December 15, 2000
  18. Tyrian Purple
    From: Mary Townsend, August 28, 2000
  19. Turtles eating Sea Hares
    From: Michael D. Miller, May 5, 2000
  20. What Preys on Sea Hares?
    From: Claire, March 7, 2000
  21. Slugs that squirt ink
    From: Orso Angulo Campillo, November 25, 1999
  22. A new review of Sea Hare defence mechanisms
    From: Bill Rudman., August 14, 1999
  23. Re: Opaline Gland
    From: Assaf Zvuloni , June 28, 1999
  24. Re: Sea Hares - attack and defence
    From: Assaf Zvuloni, June 23, 1999
  25. Sea Hares - chemical defence
    From: Tom Nolen, February 22, 1999
  26. palatability of sea hares: personal experience
    From: Patrick Krug, Ph.D., September 9, 1998
  27. Re: Sea Hares - attack & defence
    From: Conxita Avila, May 19, 1998
  28. Re: Sea Hares - attack & defence
    From: P.M. Johnson, April 21, 1998
  29. Sea Hares - attack & defence
    From: P.M. Johnson, April 17, 1998

Show factsheet and all related messages