Assessment of Artisanal Fisheries in the Peruvian Amazon
Florida International University
August 5, 2009
Acknowledgements: I would like to extend my thanks to The Explorers Club Youth Activity Fund and The Florida International University Honors College for supporting my research project with grants. The FIU Honors College study abroad program in the Amazon was a wonderful learning and life experience that I am truly grateful for.
Abstract: During July 2009, fishing habits and catches of local fishermen on the Orosa River in the Peruvian Amazon were studied. Fish were caught for immediate consumption as well as for preservation and later use and/or sale to larger urban centers. Nine fishermen were surveyed and interviewed. Their catches were measured, weighed and identified. A total of 23 species of fish were recorded from gill net catches with favored fish species being Brycon and Prochilodus (Characidae). Initial work for construction of a demonstration fish pond at the Madre Selva Biological Station was also completed during the period of the study.
Introduction: This research project focused on the fishing habits of the Yagua Indian and the mixed or mestizo fishermen in the communities of Comandancia and Santo Thomas, close to the Madre Selva Biological Station in the state of Loreto, Peru. Both communities are located on the whitewater Orosa River, a southern tributary of the Amazon. An assessment of the local fisheries was the ultimate goal, although field conditions resulted in the collection of less data than desired. Nevertheless the data and information collected provide a baseline for future research in this area and may give valuable insight into the population status of certain species of fish in the Orosa River. Furthermore, it may be useful in providing recommendations for fish species to be raised in the aquaculture pond that is currently under construction at the Madre Selva Biological Station.
Figure 1: (below left) Map of Peru showing area of project in northeastern Peru
Figure 2: (above right) Map of Loreto province, northeastern Peru, showing location of the Orosa River and the Madre Selva Biological Station.
Due to the widespread availability of river transport along the waterways of the Amazon, particularly during high water months, local and regional economies are linked to national and even international networks of trade. Motorized boats ranging from dugout canoes to large
Figure 3: Motorized wooden boats typical of the Amazon and its tributaries in northeastern Peru.
river launches link remote communities with larger urban centers such as Iquitos which is accessible from ports in Brazil, other areas of Latin America and even the United States. It is not surprising then, that the people of Comandancia and Santo Thomas have largely abandoned traditional techniques of hunting and fishing with blow-guns, bows, arrows and spears in favor of more efficient shotguns and modern nylon gill nets. More effective hunting/fishing methods combined with long-range transportation means that increasing amounts of wild game and fish are sold to markets in larger towns and cities such as Yanashi and Iquitos, in addition to supporting the dietary requirements of the locals. Another measure of the “modernization” of the Amazon was the surprising sight of generators, satellite phones, radios and televisions in many previously remote communities.
The use of gill nets in local communities has become the dominant fishing method as there are absolutely no fishing regulations. They are relatively cheap, available, resistant to
Figure 4: Nylon-mesh gill net being tended in the early morning by a fisherman in a home-made dugout canoe. Net floats are made from flip-flop material.
degradation and require no bait. Also, because nylon is nearly invisible in water, it is highly efficient at snaring fish. The nets are used either as drift gill nets or as fixed gill nets. Most fishing activity takes place in the early morning or late afternoon when the sun is still low on the horizon. At any other time during the day the sun’s radiation and heat make any activity on the river very difficult. The preferred time is early, from 5:00 to 7:00 am, when the mosquitoes are not as bad as in the afternoon. Another consideration for fishing times is that many fish that by day stay in deeper channels feed in shallow water by night. It is important for local fishermen to remove such fish from their nets before diurnal foraging fish, such as piranhas, become active and start feeding on trapped fish.
Drift gill nets require two canoes to be deployed successfully; a net up to 50 meters long is stretched perpendicular to river flow and allowed to drift down river. Since the bottom of the river is littered with fallen tree trunks and roots, the nets are kept toward the top of the water column. Larger mesh sizes up to five inches are used as the target fish are the local favorites: Brycon sp. (“sabalo”) and Prochilodus nigricans (“bocichico”). At the time this data was
Figure 5: “Sabalo” (Brycon sp.), a favored fish (center) with Trrporthys angulatus (“sardine”) above, and Liposarcus pardalus (“carachama”) below in the bottom of a fisherman’s canoe.
collected these fish averaged 36 cm in length and 0.75 kg in weight and were being sold locally for about three soles per fish, or in the Iquitos market for about 10 soles (one US dollar is equal to three Peruvian soles). Drift gill nets are most effective during lower river levels when fish are confined to the center of the river. The market price drops with declining water levels since fish are easier to catch and more end up at market. Because the water levels were still on the decline during the project period, this technique was only observed twice.
The preferred local method for catching fish during higher water levels is through the use of fixed gill nets. This method is convenient as it requires only one person to set and check the net. The net is usually set at dusk and drawn at dawn, however some nets appear to be left in for longer periods of time. A survey of the nets conducted in the morning hours next to Santo Thomas (the Mestizo community) revealed twelve gill nets along the banks of the community. On the other hand only three nets were found next to Comandancia, a Yagua Indian community. Some nets in both communities were covered with algae which suggests that they had been left in the water for extended periods of time. No nets were found more than half a kilometer from either community as gill nets appear to be checked daily and need to be in comfortable canoeing distance from the fisherman’s household. Furthermore, the proximity of the nets to the community prevents outside fishermen from stealing fish from them.
Fixed gill nets are usually deployed in the bays formed by vegetated river edges or between flooded tree trunks. The mesh size on these nets is smaller than that of drift gill nets and
Figure 6: Gill net showing young piranhas (Serrasalmus sanchezi) caught while feeding on another fish tangled in the gill net.
ranges from two to three inches. Even though the mesh size is uniform in size and shape, the nets do not exhibit the selectivity of those used in areas where there are only a few species of fish. Because there is a range of different species of fish with different body shapes, more species are being trapped. Small and large fish with spiny fins such the family of the armored catfish (Doradidae) can be easily entangled in these nets and do not have to be snared by the gills. Small piranhas are often snared by the front of their dorsal fin while feeding on other trapped fish. Once again the nets cover an area from the water’s surface to about 2 meters deep to avoid being tangled in anything that might be on the bottom of the river. The length of the nets varies from fifteen to fifty meters depending on the location.
Data on caught fish was collected in the morning hours when the fishermen would check their nets. For eight mornings, I kayaked the river around 5:30 am and looked for fishermen checking nets. Fishermen always agreed to have their catches measured, weighed and photographed. Sometimes there was no one out on the river, and heavy rain prevented me from going out some mornings. At other times fishermen with whom I arranged to go fishing did not show up. These factors limited the amount of data I was able to collect. In total I collected data from nine fishermen and documented 23 different species of fish being caught in gill nets. No fish caught was too small for the fishermen to keep. A small catfish weighing in at 9 grams and even an angelfish were considered fish for consumption.
Table 1: Species of fish caught in gill-nets by local fishermen on the Orosa River, July 2009.
Interviews with the fishermen revealed that smaller or bonier fish are consumed the day they are caught since they saw no point in preserving such small amounts of meat. These small fish are usually chopped up and used in a stew or a stir fry. The fact that they consume even the smallest fish indicates that fish are a large part of the local diet. This may also be an indication of overfishing on the river which creates the need to keep and consume even “second-rate” fish. Larger fish can be eaten or preserved depending on the needs of the family. To preserve bigger fish such as sabalo or bocichico, the fish are scaled and gutted, and two incisions are made on either side of the fish on the lateral line. The fish are then salted and sun dried if the weather conditions are right; otherwise they are pickled in salt broth (both methods are illustrated in the following photos, with sabalo in salt broth, and paco salted and dried). The amount of time fish remain preserved depends on the humidity. Preserved fish can be sold to the market in Iquitos or to local communities for later consumption.
Figure 7: Brycon sp. (“sabalo” being preserved by local fishermen on the Orosa River by soaking in salt brine.
Figure 8: Salted and dried “paco” (Piraractus brachypomus) being sold in the market-place in Iquitos, Peru.
Data collected and interviews with fishermen both indicate that fewer of the preferred target fish are being caught, especially during periods of high river levels. The fishermen prefer fish such as Characiformes (from the tetra family) because they are easier to handle and process and have more meat. They view the catch of fish from other taxa of fish as a growing problem though not for conservation reasons. Many species of spiny catfish can cause painful and infection-prone stings, and piranhas, even though they also belong to the tetra family, seem to have more teeth than meat, and can easily take a chunk of flesh from a careless fisherman, thus preventing further work.
Table 2: Catch weights, number of fish, and number of species from nine gill nets sampled.
Figure 9: Salted fish drying in sun at Comandancia village.
Construction and use of fish ponds such as the one currently being constructed at the Madre Selva Biological Station for demonstration purposes could help alleviate various problems currently faced by fishermen in the area. For starters, ponds could be stocked only with desirable species of fish, which could be harvested and sold during high river levels when the market price is at its peak. This would improve the economic situation of the local people in addition to taking pressure off the fisheries when fish are in the process of laying eggs. Restrictions on the use of gill nets would likely be impossible to enforce and would only put the local people in a tougher situation as fish play a large and important role in supporting their dietary requirements. Local fishermen also complained about commercial fishermen entering the river with large quantities of nets and drastically reducing local fish stocks. There is generally no legal mechanism for preventing commercial fishermen from harvesting fish on navigable rivers, even if they are doing so in a community’s traditional fishing area. Fish ponds would not face this problem as they are considered private property as much as a house or a canoe.
Ground work on the fish pond at Madre Selva Biological Station began on July 4th when the first steps were taken toward clearing the area for the dam and the teaching aquaculture pond itself. The location chosen was a small creek that winds through seasonally flooded forest about 100 m behind the kitchen and dining facilities at the station. The channel of the creek itself ranged from 1.5 meters to 2.0 meters deep, and from 2 meters to 5 meters in width. Away from the creek bed itself, low lying ground floods annually to 1 or 2 meters in depth, depending on the year. Initially machetes were used for clearing small undergrowth including spiny palms and small trees. Vines reaching from tree to tree were cut wherever possible to make chainsaw work on the bigger trees safer and easier for the station crew. This proved to be difficult and even dangerous work which puts into perspective the difficulties locals have to endure when clearing forest for new farmland. Humidity of up to 95% near ground level meant that even the best conditioned individual would be drenched in sweat after only 10 minutes of work. An abundance of ants and thorny vines forced us to evaluate every step and swing of the machete. In the end, all this time consuming work resulted in clearing only a fraction of the area an average family needs for farming purposes.
Figure 10: (left) Initial appearance of site selected for construction of an experimental fish pond (note seasonal creek that flows only after heavy rains).
Figure 11: (right) Seventy kilogram block of wood used for driving supporting posts for construction of the fish pond dam.
Following the initial clearing work and determination of the actual location of the dam, 4” x 4” hardwood posts were cut from naturally fallen trees and driven into the ground to form supports for the dam. Posts were placed in parallel lines two meters apart (for both the lines and the posts). This work was initiated on July 16th. A homemade pile driver consisting of a tripod of long poles, a 70 kg block of wood along with rope and cable were used to drive the posts into the ground. Boards nailed to the posts form a “coffer” that would then be packed with clay and excavated from the pond side of the dam. This formed the core of the dam, with fiberglass gunny sacks filled with clay built up on both sides of the “coffer” for added support. Eight-inch diameter PVC tubing set into the base of the dam allowed water levels to be lowered at will, and two “overflow” areas were designed to allow excess water to spill through screened areas in the event of heavy rains.
Figure 12: Pile-driver setup using a tripod of long poles, cord, pulley and heavy block of wood.
The actual length of the finished dam will be 100 meters. After our student group departed on July 22nd, field station crew continued work on the dam. The remaining supporting posts were driven in and boards for the retaining wall were cut and hammered in place. The dam was near completion on August 12th when clay soil bags were packed around the wooden core of the dam. Actual flooding of the pond will likely take place in early September, 2009 when the PVC drain pipe is blocked and water flowing through the creek is retained by the dam. Once the water reaches acceptable levels and the dam is checked for any possible leaks fish can be introduced.
Figure 13: Core area of future fish pond cleared of brush and debris. Depth of creek bed is about 1.5 meters lower than the surrounding soil surface.
Summary: As a result of this project valuable data and information regarding the fishing habits of the Yagua Indian and the mixed or mestizo fishermen in the communities of Comandancia and Santo Thomas were collected. Nevertheless, a complete assessment of the artisanal fisheries in the Peruvian Amazon would require more time and individuals involved in collecting of catch data. Ideally a group of three people would comfortably collect data from up and down river locations on a given morning. Furthermore, other fishing methods such as spearing are still utilized from time to time and need to be surveyed. Spearing of Arapaima gigas (paiche – the largest freshwater fish in the Amazon) has moved this fish to the endangered species list. Farming this highly valued fish in the new pond at Madre Selva Biological Station is viable and would aid in marketing the concept of the fish pond to local communities. Future data collection and initiation of fish pond construction in these local communities is something I remain deeply interested in researching. Adaptation of fish ponds in the region would be a great step toward sustainable development in the Amazon.