Imagine a world with no seafood. There will be virtually nothing left to catch form the world's oceans in less than a generation if current trends continue according to a major scientific study. Writing in the journal Science, an international team of researches predicts there will be almost no fish and shellfish left to harvest by 2048. Over harvest, pollution and habitat loss are the primary culprits for this grim prediction of a fishless future.
The extensive research incorporates scientists from many institutions in Europe and the Americas and draws on a variety of data. Worldwide overfishing is a major problem according to the researchers. "Every year it's estimated that human beings remove 150 million metric tons of life from the seas, stated Joshua Reichert, environment-program director at Pew Charitable Trusts in Philadelphia.
Nearly 30 percent of the species hauled from the sea have collapsed, meaning they have declined to less than 10 percent of their original yield. Larger ships, bigger nets, and modern technology for locating fish all combined to increase the global catch, but since 1994 the ocean harvest has fallen by 13 percent. The indiscriminate netting of fish in some countries has hastened this collapse.
State waters stretch for nine miles offshore in Texas and the fishery remains productive. In deep South Texas state game wardens are kept busy year round protecting local waters in the Gulf and Rio Grande from illegal commercial fishermen from Mexico.
According to Captain Ken Baker, in the past four years wardens based out of the Brownsville office have confiscated 358,000 feet of long line and more than 25,000 feet of illegal gill net along with seven Mexican shark boats. That is approximately 75 miles of long line or enough to stretch all the way form Brownsville to Raymondville and back again.
Up the river at Falcon Lake, Captain Chris Huff and his wardens have seized 202,775 feet of net from September 2005 to July 2006. "We have had several big operations down on Falcon and continue to hammer them on a daily basis," Huff said.
"Our state waters are in good shape right now, with the exception of red snapper, which we share out into the Gulf," said Larry McKinney Director of Coastal Fisheries. "One of the reasons we are in good shape is that we closely regulate our commercial fishery here in Texas."
The primary reason for decline in red snapper continues to be bycatch from shrimp trawlers. As much as 80 percent of every year class of Gulf red snapper is killed in shrimper's nets according to the Coastal Conservation Association (CCA). Legal action is being pursued by CCA seeking significant bycatch reduction from the Gulf of Mexico shrimp fleet and calling for bycatch quotas, closed areas and reduction in shrimping effort.
"Basically, for every pound of shrimp we bring in we catch about four pounds of other species," McKinney said. The bycatch issue is a worldwide problem as huge oceanic factory ships with miles of net encircle not only the species targeted such as mackerel, but also indiscriminately ensnare and kill other species by the thousands. This greatly reduces species diversity and hastens the demise of interdependent creatures.
However fishing pressure is not the only problem, as pollution and habitat loss also threaten the state and the world's fishery. The damage to estuaries and reefs due to dredging and contaminants destroys valuable nursery habitats for fish and excessive nutrient loading is fueling harmful algal blooms. Mercury levels in many species such as tuna and billfish are deemed too high for regular consumption.
A major concern in the Gulf of Mexico is the "Dead Zone" off the coast of Louisiana and Texas. This summer the area grew to some 6,700 square miles, roughly the size of the state of New Jersey according to the National Oceanic and Atmospheric Administration (NOAA).
The "Dead Zone" is an area in the Gulf of Mexico where seasonal oxygen levels drop too low to support most marine life. It is caused by a vast outflow of nutrients such as nitrogen and phosphorous from the Mississippi and Atchafalaya rivers. The tremendous nutrient loading, primarily from fertilizer runoff, promotes excessive algal growth which decays and settles on the bottom. The decaying algae consume oxygen faster than it can be replenished from the surface, leading to decreased levels of dissolved oxygen.
According to NOAA, research indicates that nearly tripling the nitrogen load into the Gulf over the past 50 years has led to the heightened hypoxia problem. Researches blame the 1.6 million metric tons of nitrogen, much of it from farm fields that washes down the Mississippi each year. The hypoxia begins in late spring, peaks in midsummer and dissipates in the fall, but while it lingers it becomes a killing zone for many marine species.
Dead zones are becoming more common worldwide in areas where coastal waters are swamped with nutrients, particularly nitrogen from sewage and fertilizer. The oxygen depleted waters are rendered unsuitable for fish and shellfish and millions may die.
Over the past few decades harmful algal blooms have increased throughout the worlds coastal waters. In the United Sates only a few regions were previously affected, but now virtually every coastal state has reported major blooms. South Texas has had several bouts of persistent brown tide and the more toxic red tide.
The increase in toxic tides is not fully understood, but excessive nutrient loading associated with coastal development fuels their growth. In 1986 a red tide bloom killed an estimated 22 million fish from Galveston to the Rio Grande and, a series of blooms have followed including one in the upper Laguna Madre this year.
There is hardly a global problem that isn't made worse by out of control population growth, and depletion of the ocean's resources is directly impacted by soaring population. The world population is approaching seven billion and rising with more and more people relying on the sea for nutrition. The United States has topped 300 million and is growing faster than any other industrialized country. The US added 100 million people in just the last 39 years and the next 100 million are predicted to come even faster, sometime around 2040.
More than half of Americans live within 50 miles of the Atlantic, Pacific, Gulf and Great Lakes coasts according to the Center for Environment and Population. This concentration of development along the nation's coastlines continues unabated and has caused an increase in pollution from improperly treated sewage, fertilizer runoff from suburban lawns and golf courses and affected water quality in sensitive estuarine environments.
"We are cutting up a smaller and smaller pie among more and more people," McKinney said. "We are trying to work toward seeing we have enough fresh water coming in and trying to protect water quality for our coastal environment."
Not everyone is convinced that the ocean's fisheries are on the verge of collapse, but the study's findings that nearly 30 percent of fish species have already collapsed due to overfishing, pollution and habitat loss is at the very least a dire warning signal.
Most agree that that there is still time to save marine life, but to protect the world's fishery will require prompt action on a global front. While ocean life is still diverse enough for the ecosystem to recover global protections must be increased. New marine reserves, better management to prevent overfishng and tighter controls on pollution could make the difference as to whether the next generation has a viable ocean fishery.
Copyright 2007 Richard Moore