08/25/03 - Colorful fish & eels
After yesterday evening's second sub dive concluded, we steamed forth 86 nautical miles from our location at the northern Lophelia Banks to the proposed Marine Protection Area. We arrived shortly before dawn, giving us an hour to dip-net fish before the sky lightened too much for our artificial lights to successfully attract fish to the boat. We caught quite a few flyingfish, and one actually jumped right up onto the deck! Jeremy Potter caught a flat needlefish.
Ablennes hians is easily distinguished from other needlefish by the 15-20 dark bars on its sides. Its deep body is strongly compressed. If it weren’t for its elongated jaws, which form a long, fragile beak, it might at first glance be mistaken for a thin river eel. These fish are easily disoriented around artificial light -- perhaps accounting for our success in netting - and may leap from the water, becoming living javelins! The flat needlefish's habitat ranges from the Chesapeake Bay south to Brazil. It also is found worldwide in tropical areas.
The primary purpose of this morning's dive was to collect video of the MPA site. In stark contrast to the coral-littered floor of the Lophelia Banks, the ocean floor here is mostly sandy. The sand came from the erosion of the Appalachians, which at one time were as high as the Himalayans. As the continental plateau erodes, large slabs of rock push toward the shelf edge. Smaller pieces break off, forming boulders. Some of these boulders eventually fall over the edge of the continental shelf, creating hiding places for various bottom-dwelling life forms. With the exception of a few invertebrates (spiny oysters and a sea star), fish dominate this area of the sea. The video footage shows fish of all shapes and sizes, with brilliant colors and of great diversity. It looks more like what one would except to see in the tropics, not under the Atlantic.
Unfortunately, views from the sub also showed an inordinate quantity of discarded or lost fishing gear. An enormous ball of monofilament line sat on the ocean floor among the boulders sheltering the fish, and stray lines floated here and there. Another sad commentary: two beer cans that spoiled this wonderful place. Many aquatic species, both freshwater and marine, have paid with their lives when they got tangled in, or ingested human trash. When manmade substances are floating through the water column, aquatic animals can easily mistake them for food.
During this afternoon's sub dive we collected samples, including startling red and yellow fish, with colors so vibrant that they looked like a child's painting. Some were entirely red, some red with a lateral yellow stripe, and one was yellow with a pink lateral stripe. Additionally, we found a conger eel and three moray eels.
The moray family of eels includes 12 species. Morays have no
pectoral or ventral fins. Instead, their dorsal, tail and anal
fins form a single, continuous fin that begins behind the head,
encircles the tail and extends midway down the belly. Their heavy,
scaleless bodies are coated with a clear, protective mucous layer.
Morays constantly open and close their mouths, which is often
perceived as a threat. In reality this behavior is necessary to
move water through their gills for respiration. The conger eel's
dorsal, anal and tail fins also are continuous, but unlike morays,
they also have pectoral fins. Foraging at night and remaining
hidden in deep coral recesses during the day, these eels are rarely
|Previous Log||Next Log|