At least 32 species have been observed in the mobile scavenger stage and the enrichment opportunist stage which are whale fall specialists and many have never been observed in any other ecosystem (Smith and Baco, 2003). The specialists extend across a wide range of taxonomic and functional groups which appear to be specially adapted to fit a certain niche within a whale fall community. They include: whale bone feeders, bacterial grazers, and chemoautotrophic endosymbionts (Smith, 2006).

A particularly interesting group of bone feeders is the genus Osedax (figure 5) which was discovered in 2002. The genus encompasses seven species of annelid bone eating worms (Rouse et al., 2004) which exclusively bore into the lipid rich bones of mammal carcasses (figure 6) predominantly in the sulphophilic stage of whale decomposition (Braby et al., 2007; Treude et al., 2009).

The limpet Ilyarachna profunda is an example of bacterial grazer in a whale fall ecosystem and Bathymodiolin mussels are chemoautotrophic and use endosymbiosis with bacteria in order to provide nutrition for survival and growth.

Osedax japonicus. ©Norio Miyamoto/Naturwissenschaften

Figure 5. Osedax japonicus. ©Norio Miyamoto/Naturwissenschaften

Osedax spp. attached and boring into a whale bone. ©2004 MBARI

Figure 6. Osedax spp. attached and boring into a whale bone. ©2004                                                   MBARI.

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