Skip to main content

Thank you for visiting You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

Cleaner fish really do clean


The cleaning of client fish by cleaner fish is one of the most highly developed interspecific communication systems known. But even though it is a seemingly obvious mutualism1,2, several quantitative studies3,5 have failed to show any benefit for the clients, leading to the hypothesis that cleaner fish are ‘behavioural parasites’ that exploit the sensory system of the clients6 to obtain food, rather than to increase the client's fitness. The cleaner fish Labroides dimidiatus eats parasitic gnathiid isopods, which decline in number on the client fish Hemigymnus melapterus daily between dawn and sunset7,8. I find that the cleaner fish reduces parasite abundance, resulting in a 4.5-fold difference within 12 hours, supporting the hypothesis that cleaning behaviour is mutualistic.

This is a preview of subscription content, access via your institution

Relevant articles

Open Access articles citing this article.

Access options

Rent or buy this article

Prices vary by article type



Prices may be subject to local taxes which are calculated during checkout

Figure 1: Gnathiids on caged fish on reefs with and without cleaner fish.


  1. Trivers, R. L. Q. Rev. Biol. 46, 35–57 (1971).

    Google Scholar 

  2. Hammerstein, P. & Hoekstra, R. F. Nature 376, 121–122 (1995).

    Article  ADS  CAS  Google Scholar 

  3. Losey, G. S. Symbiosis 4, 229–258 (1987).

    Google Scholar 

  4. Grutter, A. S. J. Exp. Mar. Biol. Ecol. 196, 285–298 (1996).

    Google Scholar 

  5. Grutter, A. S. Oecologia 111, 137–143 (1997).

    Google Scholar 

  6. Losey, G. S. Anim. Behav. 27, 669–685 (1979).

    Google Scholar 

  7. Grutter, A. S. Mar. Biol. Prog. Ser. 130, 61–70 (1996).

    Google Scholar 

  8. Grutter, A. S. Mar. Biol. (in the press).

  9. Clements, K. C. & Stephens, D. W. Anim. Behav. 50, 527–535 (1995).

    Google Scholar 

  10. Dugatkin, L. A. Cooperation Among Animals (Oxford Univ. Press, 1997).

  11. Paperna, I. & Por, F. D. Rapp. Comm. Int. Mer. Medit. 24, 195–197 (1977).

    Google Scholar 

Download references

Author information

Authors and Affiliations


Rights and permissions

Reprints and Permissions

About this article

Cite this article

Grutter, A. Cleaner fish really do clean. Nature 398, 672–673 (1999).

Download citation

  • Issue Date:

  • DOI:

This article is cited by


By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.


Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing