Unique Species

            Whale falls hold host to a large variety of species. The depth of the whale fall usually dictates the fauna found on whale carcasses. At very deep depths, whale falls share many organisms with cold seeps and hydrothermal vents (Bennett et al 1994). It is believed that whale falls present a stepping- stone for species in order to colonise other sites. 

            In mid depth to shallow, the species are usually endemic scavengers to the area and you see fewer vent and seep fauna. 

Figure 3. Greendland Shark

Vertebrates 

Sleeper shark- (Somniosus pacificus) is the pacific species. In the North Atlantic is also known as the Greenland shark (Somniosus microcephalus). Known to feed on fish, squid and carrion (Yang, 1999). The size of a whale carcass is an inviting high- energy meal, with minimum energy expenditure. 

Hagfish- There are several species of hagfish, most are predators, but also eat carrion. The main hagfish species associated with whale carcasses are (Myxine glutinosa) in the Atlantic,  (Eptatretus cirrhatus) New Zealand Hagfish and the Pacific hagfish (Eptatretus stoutii). The hagfish is a primitive fish due to its cartilidge skull and lack of boney vertebrate. 

 

Figure 5. Rat- tail or grenadier

Rattails- also known as grenadiers, are some the most abundant fish of the deep  sea. Most are avid predators of small fish, invertebrates and even small cephalopods. However many supplement their diet with carrion. (Priede et al 1990) The most notable are the Coryphaenoides.

Invertebrates 

Echinoderms- Starfish and brittlestars are the most common, but also urchins. Echinoderms are major scavengers and predators at shallower depths. 

Figure 6. Munidopsis spp.

Crustaceans- Munidopsis spp. Are a common sight at the edges of hydrothermal vents. They are commonly found grazing on the bacterial mats that cover the sediments. Galatheid squat lobsters are also found at cold seeps and have been discovered on several whale falls.

Osedax- annelid species, only occurs on mammal bones. The annelid uses its roots to burrow into the boot and bacteria in the roots breakdown the sulphides in the marrow and bone giving the worm sustenance. This is

Figure 7. Osedax spp

a prime example of symbiosis. The females are much larger than the males. The males are so small that they live with the females tube. The females tube contains numerous males. in this case the males are only sperm packages for the female and depend on the female for energy and safety. (Rouse et al 2004) 

Molluscs- several species of molluscs inhabited whale falls. The majority feed on the organic rich sediments that surround the carcass, however some contain chemosynthetic bacteria to provide energy for them, these include vesicomyid clams. Limpets and mussels (Idas spp) attached to whale bones (Smith et al 1998).

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