Habitat
Steller narrated, that the north-eastern littoral of Bering Island is covered with numerous rocks and rough cliffs, and during low tide becomes exposed for up to five verst [about 5 kilometres].
"It [the animal] never goes on the dry land, also never moves far away from the shore. At low tide it keeps away from shore, so that it will not strand. As soon however as the flood is back it comes again near shore and ingests its food."
And Steller:
They probably drank the fresh water to "balance their electrolytes".
One mayor question remains unanswered:
Was the Seacow able to dive,
or was it too buoyant?
Steller wrote on this
*)in de Bestiis - translated by Miller:
"Half of the body, the back and sides, projects above the water
... it has to live, not in the depths of the sea, but it is always compelled in feeding to expose half of its body to the cold.".
" ... its back is at all
times visible above the water, because more sea grass [kelp] grows in the shallow water than in the deep".
If we assume that the animal was unable to submerge at all due to its low specific weight, this floating way of life would have had a number of benefits and disadvantages
*)after Domning 1978, P. 130f:
Benefits | Disadvantages |
The animal could graze comfortably the algae in the safe
shallow water, reduction of wave drag, reduction of heat loss, sea gulls could remove parasites
| Deeper plants are unavailable, in subzero air temperatures problems of drying of the skin
|
It is hard to believe that evolution should have neglected these
serious disadvantages.
"The value of total submergence under adverse condition would probably have been too great for diving ability to have been totally lost; nonetheless the evidence indicates to me that for Hydrodamalis ... floating was the preferred posture for normal activity."