Hail Your Majesty!

Ever wondered who’s King of the sub-Saharan African waters? Who enjoys the luxury of having hundreds of attendants giving him a great spa while he chills and relaxes in the cooling waters? Hail to King Hippopotamus! Unlike many other animals that clean and groom themselves, or engage in allogrooming which “is performed by one animal upon another animal of the same species”[1], the hippopotamus (Hippopotamus amphibius) relies on an entourage of fish to give it a good cleaning and grooming session every now and then. In return, the hippo rewards its attendants with a sumptuous feast of algae, parasites, and dead skin scraped from its hide and dung! Here’s a peek at the royal spa:


 (If unable to view, please double-click the screen.)

While symbiotic relationships between hippos and fish have long been documented, Deeble and Stone (2001) made a bonus discovery when they started taking photographs beneath the surface of Kenya’s Mzima Springs for the first time. They found that different species of fishes are highly specialized in cleaning specific body parts of the hippopotamus. The genus Labeo, under the family of carps, is the main cleaner, using its large mouth to scour the hippo’s hide, teeth and palate. Barbel fish (Barbus) gets the “dirtier” job of cleaning the hippo’s feet—the cracks in its soles and gaps between the toes—as well as its hind. The smaller Cichla fish feeds among the tail bristles while tiny Garra tends to the master’s wounds.

But the hippopotamus does prove itself to be a thoughtful master after all. As observed from the video, it would proactively move to spots where the fishes are more densely populated, and would also open its mouth and spread its legs so as to facilitate the whole cleaning process. Little aggression is observed and the hippo seems tolerant of the large number of fishes nibbling off its body. As gross as it may sound, these fishes actually get a lot of nourishment from feeding on the hippo’s dung and on the waste from its skin. It is no wonder that fishes aren’t the only animals willing to serve this great king. Studies have shown that many birds have also been observed to help groom the hippo by feeding on insects and parasites from its back. The more commonly observed bird species include the Common Sandpiper (Tringa hypoleucos), African Pied Wagtail (Motacilla aguimp), Red-billed Oxpecker (Buphagus erythrorhynchus) and Yellow-billed Oxpecker (Buphagus africanus) (Olivier and Laurie, 1974). The high incidence of open wounds on hippos’ backs, a result of high levels of intraspecific aggression, provide a rich food source for these birds, but it is indeed interesting how hippos are aggressive to its own kind, yet a gentle giant to others!   

 Hippo

 Picture taken from: http://www.nwf.org/News-and-Magazines/National-Wildlife/Animals/Archives/2004/In-Heaven-With-Hippos.aspx (see Ref 4)

 


References:

 [1] “A Dictionary of Ecology”, by Michael Allaby. Encyclopedia.com, 2004. URL:http://www.encyclopedia.com/doc/1O14-allogrooming.html (accessed on 04 Apr 2010)

[2] “Fish Cleaning Hippo” by National Geographic. Youtube videos, 20 Jul 2008. URL:http://www.youtube.com/watch?v=6-zv9Jh-6Ck (accessed on 04 Apr 2010)

[3] “In Heaven With Hippos”, by Heidi Ridgley. National Wildlife Magazine, 06 Jan 2004. URL: http://www.nwf.org/News-and-Magazines/National-Wildlife/Animals/Archives/2004/In-Heaven-With-Hippos.aspx (accessed 04 Apr 2010)

[4]“Kenya’s Mzima Spring Comes Alive”, by Mark Deeble and Victoria Stone. National Geographic Magazine, Nov 2001. URL:http://ngm.nationalgeographic.com/ngm/data/2001/11/01/html/ft_20011101.fulltext.2.html (accessed 03 Apr 2010)

[5] “Mizma Springs — Haunt of the Hippo”, by Tomas Hroch. Eng.Hrosi.org, Sep 2007. URL: http://eng.hrosi.org/?id=34 (accessed on 03 Apr 2010)

[6] Olivier, R.C.D. & Laurie, W.A., 1974. General Notes- Birds Associating with Hippopotamuses. Auk, 91(1): 169-170

[7] Olivier, R.C.D. & Laurie, W.A., 2008. Habitat Utilisation by hippopotamus in the Mara River. African Journal of Ecology, 12(4): 249-271

[8]  Zubkowicz, R., 2005. Selected Problems of Organising Exhibition Areas for common Hippopotamus (Hippopotamus amphibius)- Zoological Data. Annals of Warsaw Agriculture University – SGGW, Horticulture (Landscape Architecture), 26: 211-218