Im a Clownfish! Hear Me Roar!!!!

by | Jan 12, 2012 | Fish, Science | 1 comment

So, during my daliances in the scientific literature I came across a title of a new paper that I just had to read. This manuscript, published in BMC Evolutionary Biology, entitled, Interspecific variation of calls in clownfish: degree of similarity in closely related species” opened my eyes to something that I am sure not very many hobbyists have thought of, that being fish actually calling to each other. I guess that they, like me, presume fish do not vocalize. Well, I was most assuredly wrong. The research published by Colleye et al. sheds light on this fascinating phenomenon.


In the manuscript it is detailed that clownfish are in fact quite prolific callers and do so aggressively to defend their territory and keep other clowns away. Using sonography and recording the morphological features of members of 14 different clown species, the reserachers showed that the characteristics of calling such as the frequency of the sound pulse, the pulse duration and the timing of the pulses closely correlate to fish size. In fact the correlation is so strong that it is actually possible to estimate the size of the fish making the call from the sound it is creating. Between the three acoustic criteria studied, only the pulse period differed to any extent between clown species. Thus, based on these facts, it would appear that calls are generated by clowns to keep other smaller clowns away from their territory, since only size, not species, can be inferred from the sound.

In an interesting twist, separate species of clown that frequently cohabit within a single anemone (as in the case of Amphipirion sandaracinos and A. chrysopterus or A. periderion and A. clarkii) have sufficient pulse period differences that each species is able to distinguish between calls, and thus determine the species of the caller as well as estimating the size. This greatly reduces apparent aggression within the territory between the two species since the calls of a larger clown of the opposite species can effectively ignored. The same cannot be said for other sympatric (living in close proximity) species which cannot distinguish between calls. From this, it can be conferred that the sound producing mechanism is highly conserved and its use to defend territory, and mates, has helped define individual species by preventing diversification through interbreeding.
Finally- from a purely personal viewpoint, over my years of fish keeping I have had several very large A. clarkii. Once in a while I would notice these guys snapping their jaws, making a cracking sound. At the time I thought they were just being odd… apparently not. This is exactly the type of behavior this article examines. Who would have thought my clowns were actually shouting!

  • Paul Whitby

    Paul Whitby is originally from the UK, but now resides in Oklahoma USA. While in the UK, he received his Doctorate in the microbiology of fish diseases, specifically diseases of fish with high economic importance and has published several articles in this field as well as medical microbiology. Currently he is an Associate Professor at the University of Oklahoma where he specializes in the microbiology of pediatric infectious diseases. Paul is the current President of the Central Oklahoma Marine Aquarium Society (COMAS) and has had several articles published in Reefs Magazine, Reef Keeping magazine and Reefs.com and ReefBuilders. He has published several articles on COMAS, the development of a captive propagation program to conserve coral species, pests and parasites in marine aquaria as well as numerous reviews. In October 2007 his SPS dominated display tank was selected as Reef Keeping Magazine's Tank of the Month. Paul has presented several marine aquarium related seminars at local clubs and conferences including Oklahoma's CRASE, Reef Fest, ReefStock, NERAC, IMAC west and others. In association with his good friend Ed Brookshire, Paul owns Highdefcorals.com He has been keeping saltwater aquariums for over 22 years and has owned a variety of tanks ranging from under 30 to in excess of 600 gallons. His current system, including filtration, is over 1,000 gallons.

    View all posts

1 Comment

  1. RARECLOWNSNJ

    Paul, great article and awsome information.

    This further throw a kink in the theory of white bonnet clowns and theilli.

    The loudest i have ever heard was my large akinydnos female 5inches, It would sound like a pistol shrimp.

    Reply

Submit a Comment

Your email address will not be published. Required fields are marked *