The depth at which an Emperor Penguin can dive is dependent on the extent to which sunlight can penetrate the ice water according to research. The extent of at which light can penetrate the ice water is also dependent on the degree of ice cover on the ocean. As a result of this, <em>as the depth of dive of an Emperor Penguin increases, visibility also decreases as light penetration reduces. In order words, lack of sunlight would reduce visibility as the diving depth of the Emperor Penguin increases.</em> That is why most deep dives have been found to occur in spring time when light penetration is high as a result of sunlight availability.
On day one the levels of oestrogen and progesterone are low, having dropped quickly at the end of the last cycle. Low oestrogen level causes FSH release from the pituitary gland.
