16:3And the second angel poured out his bowl into the sea, and it became blood like that of a dead man; and every living thing in the sea died.

And the SECOND ANGEL poured out his BOWL into the SEA,

This bowl follows the first bowl very rapidly. Mankind still is struggling with sores, and now this plague appears.

"Into the SEA" implies that whatever makes the sea become BLOOD is water soluble.

and it became BLOOD like that of a dead man;

The sea (oceans) became like a dead person's blood: putrefying, black, foul, and clotted blood (Dr. Ella Rust). Compare this to the Egyptian plague (Exodus 7:20-24 and Psalm 105:26-29-36). The Nile stunk and was not potable. BUT that plague was localized to Egypt.......this one is earth wide.

Chemically, sea water is almost identical to blood. Only the iron rich (red coloration) hemoglobin in the corpuscles carry the life-giving oxygen throughout the body (Leviticus 17:10-13). The BLOOD in this plague is not circulating nor is it being enriched with oxygen. Hence the result:

and EVERY LIVING THING in the SEA DIED.

Ponder the impact this has on the earth! Fisheries and maritime industries shutdown. The stench along the coasts (where many of the world's largest cities are located) is overwhelming. Scientists will be at a loss to eradicate the plague, and it can't be contained as it is EVERYWHERE.

Red Tide AlgaeThe "red tides" which occur frequently in the Gulf of Mexico and other parts of the world may be a small example of this plague. "Retides" are thought to be caused by dinoflagellata (one celled organisms - Karenia brevis).Red Tide

While science still has many unanswered questions about dinoflagellata, could this be a byproduct or relapse of a previous trumpet (Revelation 8:8-9)? Incidentally, the dead fish during the "red tide" contain a potent nerve poison. This poison's effect on humans is not presently known.

Symbolically, this has been interpreted as either 1) a massive navel battle or 2) moral death of the human spirit. However, this raises more unanswered questions than are raised by the literal interpretation.

This completes the "life cycle" of the seas (Genesis 1:21). If sea (water) is the container of spirits, then this BOWL along with the next bowl effectively removes the spirit habitation. As much as the devil has always tried to kill mankind before they can make a choice to become a believer, this plague may be God's way of killing demons (or their dwelling places, at least). Interestingly, when old earth and old heaven are removed, so is the sea (Revelation 21:1). This probably means God will not even give a chance to some evil leader like the devil to clean up the sea and possibly reintroduce demons. The new heaven and earth apparently are without seas.