4
1 Introduction
meeting waters (Franklin 1786; Darwin 1845; Beebe 1926; Cushman Murphy
1944); it was also evident that some fronts were related to special bottom or coastal
configurations (Uda 1938). However, the ecological properties and functioning of
marine fronts has not been studied in detail until recently (Russell et al. 1999).
Box 1
Ancient reports of fronts: Outstanding biological activity attracted the
attention of ancient voyagers and scientists. In the past, this fact could have
been more notorious than nowadays because of a lesser impacted ocean
(fishing, contamination) and because of the use of slower and less disturbing
vessels (i.e. sailing ships).
In one day we passed through two spaces of water thus stained [by Cyanobacteria of
genus Trichodesmium], one of which alone must have extended over several square
miles… The line where the red and blue water joined was distinctly defined. The weather
for some days had been calm, and the ocean abounded, to an unusual degree, with living creatures… how do the various bodies which form the bands with defined edges keep
together? …what causes the length and narrowness of the bands? … We must believe that
the various organized bodies are produced in certain favourable places, and are thence
removed by the set of either wind or water
(Darwin 1845)
The front moved past us, and we lay for some time in a turbulent area which contrasted
strongly with the preceding glassy calm … The surface was seething, boiling, with life,
much of which was de profundis. Larvae of clawless lobsters, tinted jellyfish, nurse chains
of salps, small herringlike fishes, a silvery hatchetfish with its face bitten off, rudder-fishes
hanging head downward, luminous lantern-fishes with shining light-pores, red and purple
swimming crabs, other creatures which we could not name at sight, and much that was too
small even to see distinctly—all swarming about under the searchlight, while pink squids,
from a few inches to a foot or more in length, kept darting from below, causing the showers of fry from water to air and back again. A general holocaust was in progress. The little
fishes were eating invertebrates or straining out the plankton; the squids were pursuing
and capturing fishes of various sizes; and the blackfish were no doubt enjoying the squids
(Cushman Murphy 1944)
1 Introduction
meeting waters (Franklin 1786; Darwin 1845; Beebe 1926; Cushman Murphy
1944); it was also evident that some fronts were related to special bottom or coastal
configurations (Uda 1938). However, the ecological properties and functioning of
marine fronts has not been studied in detail until recently (Russell et al. 1999).
Box 1
Ancient reports of fronts: Outstanding biological activity attracted the
attention of ancient voyagers and scientists. In the past, this fact could have
been more notorious than nowadays because of a lesser impacted ocean
(fishing, contamination) and because of the use of slower and less disturbing
vessels (i.e. sailing ships).
In one day we passed through two spaces of water thus stained [by Cyanobacteria of
genus Trichodesmium], one of which alone must have extended over several square
miles… The line where the red and blue water joined was distinctly defined. The weather
for some days had been calm, and the ocean abounded, to an unusual degree, with living creatures… how do the various bodies which form the bands with defined edges keep
together? …what causes the length and narrowness of the bands? … We must believe that
the various organized bodies are produced in certain favourable places, and are thence
removed by the set of either wind or water
(Darwin 1845)
The front moved past us, and we lay for some time in a turbulent area which contrasted
strongly with the preceding glassy calm … The surface was seething, boiling, with life,
much of which was de profundis. Larvae of clawless lobsters, tinted jellyfish, nurse chains
of salps, small herringlike fishes, a silvery hatchetfish with its face bitten off, rudder-fishes
hanging head downward, luminous lantern-fishes with shining light-pores, red and purple
swimming crabs, other creatures which we could not name at sight, and much that was too
small even to see distinctly—all swarming about under the searchlight, while pink squids,
from a few inches to a foot or more in length, kept darting from below, causing the showers of fry from water to air and back again. A general holocaust was in progress. The little
fishes were eating invertebrates or straining out the plankton; the squids were pursuing
and capturing fishes of various sizes; and the blackfish were no doubt enjoying the squids
(Cushman Murphy 1944)