Net and Longline Fishermen

Net fishermen also fish for a range of finfish close to shore in small vessels (5 to 7 m), using gill nets that sometimes stretch over a kilometer in length. Once they have set their nets and are waiting for a couple hours to retrieve them, they will often fish with hook and line for bottom dwelling fish such as flounder (Paralychthys adspersus).

Longline fishermen tend to use larger vessels (10 to 15 m in length with inboard diesel motors), targeting shark, mahi-mahi (Coriphaena hippurus), and swordfish (Xiphias gladius). They often spend days at sea and go out as far as 80 miles offshore, depending on where the optimal water temperature and currents are found.

This group of fishermen is impacted by changes in the water temperature and depth of the thermocline, as tropical species move in closer to the Peruvian coast, making them more accessible to the fishermen. Mahi-mahi, for instance, feed on the eggs of flying fish (Cypselurus heterurus), and the flying fish are one of the first species to migrate with the warmer waters toward the coast, luring the mahi-mahi with them. During the early phases of the 1997 event, the abundance of mahi-mahi stretched down into northern Chilean waters, initially providing a steady source of income for the small-scale fishermen. However, as this ENSO began to increase in strength, an overabundance of these fish flooded the markets (both for internal consumption and for export), leading to a drop in prices. At one point, some fishermen stopped going to sea as the prices for their catch fell to very low levels ($ 1 per kilo); it was not worth their expenditures on fuel, ice, and materials.

The largest vessel of the artisanal fleet (approximately 30 gross registered metric tons) uses purse seine nets and is dedicated to the capture of anchovy, which is sold to the fishmeal plants. This group has a relative advantage during some ENSO events, as the anchovy move closer to shore in search of the nutrient-rich upwelled water, because the industrial fleet is not permitted to fish within 5 miles of the shore. This can lead to conflict and informal negotiations between the two sectors. With the total disappearance of anchovy during extreme ENSO events such as that of 19971998, some of these fishermen have modified their boats with permission and some minor subsidization from the government enabling them to trawl for langostinos, among other species that migrated down from Ecuador.

Many artisanal fishermen live in remote coastal rural villages and lack the infrastructure, such as ice machines and refrigeration systems, that enables them to store their products until the market situation improves. This makes them reliant on middlemen for the sale of their product, and often for ice, fuel, and other fishing supplies. This reliance is exacerbated during ENSO, as the temperature of the water, as well as of the air, can be several degrees Celsius above normal. Because their catches tend to spoil much faster due to the heat, they are more desperate to offload and sell their catch as soon as they reach shore.

The tendency for increased spoilage is problematic down the production chain. While it is difficult to blame directly on ENSO, there is a tendency for a sharp increase in gastrointestinal problems during the warm weather, again, due in part to a lack of refrigeration in many parts of the country, and the accelerated growth of bacteria because of adverse climatic conditions. An extreme example of the apparent linkage between ENSO and human health is the Pan-American cholera pandemic that began off the coast of northern Peru and spread across the continent in 1991. Facilitated by the 1992 ENSO, cholera destroyed the Peruvian market for artisanal fish and rapidly spread throughout South America. (Epstein, 1993). Vibrio cholera, which has been isolated from phyto- and zooplankton, is directly influenced by changes in water temperature and chemistry.

Another, perhaps equally important impact results from the increase in precipitation along the northern coast of Peru, where normally arid coastal communities can be inundated by the torrential rains. While fishermen may have an abundance of products to sell, the roads and bridges may be washed out by these rains and swollen rivers, and, thus, there is no way to get their products to market. Again, as most fishing ports lack refrigeration, the products spoil due to the interruption in transportation.

Additionally, the sea level along the coast of Peru during an ENSO warm event may rise as much as 30 cm. The sea-level height is increased as a result of the eastward shift in ocean currents and the thermal expansion of the water that results from the increased ocean surface temperatures. This, in turn, can result in many more days with dangerous storm surges as waves from storms of "typical severity" have a stronger impact on the coast. ENSO-related storms, therefore, make it too risky for the small boats to navigate out of port.

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