Aplysia californica algal preference

January 3, 1999
From: Christine Nguyen

Dear Bill,
         My name is Christine Nguyen and I am a marine biology student at Long Beach Polytechnic High School in California. For an individual research project, I am going to survey the amount of sea hares in one particular area of a tidepool in relationship to the percentage of different types of algae by using a 4 meter quadrat to then determine the sea hares' food preference in the different types of algae. I'm not finding much luck in finding information regarding algae preference, so do you have any recommendation as far as how I should go about starting my project as well as any information regarding the food preference of sea hares through research?

Your help is greatly needed and appreciated.
Thank you for your time.
                                             Christine Nguyen


Nguyen, C., 1999 (Jan 3) Aplysia californica algal preference. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/432

Dear Christine,
I guess the sea hare you are looking at is Aplysia californica. I'm afraid I am not an expert on Californian sea slugs but if you have access to either of Kandel's books, or the article which I list below you will get some background reading. Aplysia californica is now an important research animal in behaviour and learning studies and so there are many published articles on it. have a look at the website I mention in a message below of the NIH-Aplysia Resource Facility in Miami, Florida. I think the site has just been updated. It is at: http://www.rsmas.miami.edu/groups/sea-hares/. In their online newsletter Slimelines Vol 2, they discuss research on feeding Aplysia californica. However they are feeding their animals on a red algae which doesn't occur in California.

In their natural environment, Aplysia californica change their food as they grow. They normally settle out of the plankton onto red algae (often Laurencia) and then gradually move higher up the shore where they feed on brown and green algae. This is a pattern followed by species of Sea Hare throughout the world. I suspect any study you do would need to take into account the size of the Sea Hares you are counting. Since they change their food preference as they grow you would have to separate them into size groups to make any sense of your observations. However it is not just a simple change of diet once a certain size is reached because they will eat other than the preferred food if it is not available. If you look at the website on the group who are breeding Aplysia californica they feed their animals on a red algae Gracilaria for their whole life - and its a species of algae that the Sea hare would never find naturally.

Concerning the identification of algae. I am sure there must be a good book which you could use. My suggestion is that you get in touch with your local Natural History museum or see if a Botany or Biology dept at a local University can't give you some help. Surfing the web can be very useful but so can making contact with local experts.

Please let me know how your study turns out,
and if anyone in California who reads this can give Christine advice please do.

Best wishes,
Bill Rudman.

Kandel,ER (1979): Behavioural Biology of Aplysia. San Francisco, W.H.Freeman&Co.463pp.

Kandel,ER (1976): Cellular Basis of Behaviour. An introduction to behavioural neurobiology. W.H.Freeman & Co., San Francisco. 727 pages.

Stallard,MO; Faulkner,DJ (1974): Chemical constituents of the digestive gland of the sea hare Aplysia californica - I. Importance of diet. Comp. Biochem. Physiol. 49 B, 25-35.

Rudman, W.B., 1999 (Jan 3). Comment on Aplysia californica algal preference by Christine Nguyen. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/432

Related messages

  1. Aplysia californica? from Peru
    From: Leonidas Mulluhara, June 3, 2010
  2. Re: Sea of Cortez Mystery Slug
    From: Jennifer Beatty, April 5, 2007
  3. Sea of Cortez Mystery Slug
    From: Jennifer Beatty, April 4, 2007
  4. Juvenile Californian Sea Hare & friends
    From: Kevin Lee, December 12, 2006
  5. Aplysia californica from California
    From: Shannon Fabre, May 17, 2006
  6. Aplysia californica from Sea Of Cortez
    From: Gerald Hinkler, April 15, 2006
  7. Aplysia californica at Puerto Penasco, Mexico?
    From: Parker Tastrom, March 22, 2006
  8. Juvenile Aplysia californica from Monterey, CA
    From: Clinton Bauder, July 8, 2005
  9. Can Aplysia californica eat kale?
    From: John Lopez, March 5, 2005
  10. Information on Aplysia californica
    From: Michael Navarro, February 8, 2005
  11. Aplysia californica from Santa Barbara Island
    From: Chris Grossman , June 30, 2003
  12. Re: Aplysia gigantea or A. californica?
    From: Jun Imamoto, March 3, 2003
  13. Aplysia californica inking
    From: Bill Rudman, March 3, 2003
  14. Aplysia gigantea? A. californica? from Japan
    From: Jun Imamoto, February 5, 2003
  15. Which slug is used for medical research?
    From: John H. Garrett III, September 17, 2002
  16. Keeping Aplysia in aquaria
    From: Jessica Helm, August 29, 2001
  17. Re: Keeping Aplysia in aquaria
    From: Tom Capo , August 29, 2001
  18. Photos of Aplysia californica
    From: Daniel Geiger, August 1, 2001
  19. Mass mortality of Aplysia californica
    From: Jose Luis Ochoa, March 24, 2001
  20. Sea Hare classification - A. californica
    From: Rachel Frank, December 31, 2000
  21. Aplysia for brain studies
    From: Alvin Wong, September 2, 2000
  22. Information on Aplysia californica
    From: Luiza Zonzini, April 20, 2000
  23. Re: HUGE Sea Hare
    From: Ron Velarde, December 15, 1999
  24. Re: HUGE Sea Hare
    From: Diane, December 10, 1999
  25. Is this a sea slug? It's HUGE!!
    From: Diane, December 9, 1999
  26. Sea Slugs from South California
    From: Lonnie, July 13, 1999
  27. re: Need to know what we saw
    From: Eileen Steger, July 12, 1999
  28. Re: Sea Hares - mating chains
    From: Sigrid Schmalzer, July 12, 1999
  29. Re: Sea Hares - mating chains
    From: Sigrid Schmalzer, July 9, 1999
  30. Need to Know what we saw
    From: Eileen Steger, July 8, 1999
  31. Photos of Aplysia californica
    From: Daniel Geiger, March 12, 1999
  32. Urechis caupa or Aplysia californica
    From: barbara hansen, February 26, 1999
  33. Photo request for Aplysia californica
    From: Panayotis Matsinopoulos, August 3, 1998

Show factsheet and all related messages