The Peruvian anchovy fishery is constituted by the species Engraulis ringens (Engraulididae:

Clupeiformes) and is locally known as ‘anchoveta peruvana’. The species distribution extends from northern

Peru to central Chile (50S – 250S. Lat.) along the west coast of South American. A marine coastal species

distributed within 30 km off the coast. These fishes are seen in huge shoals mainly in surface waters and

during day time may descend down to 50 m

Nair, J Rajasekharan

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CMFRIWinter School onImpact of Climate Changeon Indian Marine FisheriesLecture NotesPart 1Compiled and Edited byE. Vivekanandan and J. JayasankarCentral Marine Fisheries Research Institute (CMFRI),(Indian Council of Agricultural Research)P.B. No. 1603, Cochin - 682 018, Kerala(18.01.2008 - 07.02.2008)CMFRI - Winter School on Impact of Climate Change on Indian Marine Fisheries 52Peruvian anchovy fishery; Factors affecting the resourcePERUVIAN ANCHOVY FISHERY:FACTORS AFFECTING THE RESOURCEJ. Rajasekharan NairCollege of Fisheries, Kerala Agricultural University,Panangad P.O., Kochi – 682 506, Kerala.IntroductionThe Peruvian anchovy fishery is constituted by the species Engraulis ringens (Engraulididae:Clupeiformes) and is locally known as ‘anchoveta peruvana’. The species distribution extends from northernPeru to central Chile (50S – 250S. Lat.) along the west coast of  South American. A marine coastal speciesdistributed within 30 km off the coast. These fishes are seen in huge shoals mainly in surface waters andduring day time may descend down to 50 m.Bionomics The anchovy is a very efficient filter feeder. The early larvae (apterolarvae) consume phytoplankton,late larvae (pterolarvae) and juveniles mainly feed on small zooplankton. The adults are entirelyphytophagous, more than 90% of the dietconsisting of diatoms. The species breeds throughout the year along the Peru coast with two peaks.The first peak is shown during the southern summer in January -February and the major one during latewinter in August– September. The absolute fecundity ranges from 10,000 to 20,000 for the fish length rangeof 10 to 15 cm. The longevity is three years and the growth potential is around 20 cm. The growth is 8.0 cmStandard Length in six months, 10.5 cm SL in 12 months and 12.0 cm SL in 18 months. The interestingaspect is that the fish is recruited to the fishery at around 8.0 cm SL from the sixth month onwards. Threefishery stocks are identified, one off Peru and two off Chile. The Peru stock is the most productive.HydrographyThe southeast Pacific FAO fishing region constitutes the west coast of South America along thecoasts of Ecuador, Columbia, Peru and Chile. Off the coasts of Peru and northern Chile lies one of therichest marine environments on earth – the Peruvian upwelling region – a typical west coast upwellingzone. This is the region of the cold Peru or Humboldt Current. The Peru Current carries cool, nutrient richCMFRI - Winter School on Impact of Climate Change on Indian Marine Fisheries 53Peruvian anchovy fishery; Factors affecting the resourcewaters to the north. The upwelling caused by the offshore drift of the surface waters (due to the trade windsand the Coriolis force) brings the cool (10 – 220C) nutrient rich waters of the Peru Current to the surface.These waters are rich in phosphates and nitrates. This is the cause of an enormous growth of phytoplankton(up to more than 500 mg C/m2/day) and subsequent zooplankton growth. This area supports huge populationsof small cool-water pelagics like the Peruvian anchovy and the South American pilchard (Sardinops sagax).From December to February, the warm tropical water shifts southwards along the coasts of Ecuador andColumbia and extends in a small strip, along the coast of Peru (El Viejo). In certain abnormal years thewater that is upwelled is much warmer and hence low in nutrients due to heavy warm-water incursion. As aresult there is a sharp reduction in the primary production and plankton biomass. This phenomenon ofunusually strong warm-water incursion is known as El Nino (the boy child – Christ child as the phenomenonoccurs during Christmas time). More recently it has come to be referred to as the El Nino Southern Oscillation(ENSO) event. Hence the inter-annual productivity varies greatly and with this the catches of the smallpelagic resources namely the Peruvian anchovy. Also these fishes migrate southwards and to the deeperwaters during ENSO times.Fishery The sediment core studies have shown that the Peruvian anchovy dominated the Central Peru coastsfor more than 2000 years. From 1840s the major industry along the Peru coast has been the mining of birddroppings – ‘Guano’ from the rocky islands, for use as fertiliser. Large populations of the fish eating guanobirds like cormorants             (Phalacrocorax bougaivilli), boobies (Sula variegata) and pelicans (Pelicanusthagus) are characteristic of the upwelling zones. Nearly 20 - 30 million birds have been estimated to roostalong the ‘Bird Islands’ of Peru and Chile coasts before the start of the fishing industry.After the Second World War a small Peruvian anchovy fishery started, mainly for export as cannedfish. The high oil content and hence less palatability coupled with the huge demand for an alternate cheapprotein source (fish-meal) for the giant poultry and pig industry of the developed world kick-started ahighly successful anchovy fishery. In 1949, seven fish meal plants started in Peru. The fish landings increasedto an average of 1.0 million tonnes (m t) per year during 1955 – 1959. Anchovy trawlers and purse-seinerslocally known as ‘Bolicheras’ are the crafts used for the fishery. From around 100 vessels and 30 fish-mealplants in 1954-’55, the industry grew to around 2000 vessels and 175 plants in 1968-69. This was the boomperiod for the now ‘Industrial Fishery’. The fishery peaked at 13.0 m t in 1970. Many scientists unofficiallypeg the landings at 15.0 m t in 1970. Southeast Pacific area ranked first among the Pacific fishing areas. Thetotal biomass was estimated to be 23.0 m t in 1970 and around 9.0 to14.0 m t in 1971.The climate-dependent dynamics of Peruvian anchovy is affected by strong El Nino events. The1972-’73 ENSO event led to the drastic decrease in the anchovy landings. The catches dropped to around2.0 – 4.0 m t. After the 1975-’76 event, the landings further decreased to 1.0 – 2.0 m t. The landings furthercrashed to 1.0 m t after the 1977-’78 event. The 1982-’83 ENSO, the severest of them all led to an all timelow of 0.5 – 0.1 m t catches in 1983 and 1984 with a total biomass of less than a million tons. Theenvironmental conditions stabilised after this. Thus after a protracted period     (1974 to 1985) of highlyfluctuating low landings the fishery started to recover. In 1986 it exploded back to 5.0 m t. The fisheryfluctuated between 2.0 to 5.0 m t till it reached a peak in 1994 (12.0 m t). The strong ENSO event of 1996-’97 led to a collapse in 1998 (1.8 m t), the fishery coming back strongly the next year with a catch of 8.7 mt, the year-class strength being independent of the parental population.Factors affecting the resourceThe question was whether it was over fishing or environmental changes or a combination of bothwhich led to the repeated collapse of the anchovy fishery.Environmental conditionsDrastic reduction in primary production and plankton biomass due to the El Nino events had a majorimpact on the biology of the Peruvian anchovy. The following causes are attributed:CMFRI - Winter School on Impact of Climate Change on Indian Marine Fisheries 54Peruvian anchovy fishery; Factors affecting the resourcea) Larvae fail to survive and get recruited to the fishery due to lack of phytoplankton food. Theresultant drop in catches is felt immediately because the anchovies are recruited when six monthsold.b) The adults could have starved to death for lack of diatom blooms. The interesting feature of the1975-’76 ENSO was the bloom of Gymnodinium splendens leading to unfavourable food conditionsand adult mortality.c) The anchovy is a cool water species concentrated in the low temperature zones (16 - 180 C) of thePeruvian upwelling area. During the ENSO years the shoals remain in the cool pockets within theupwelling zone. The temperatures may go up to 28 – 29 0 C. When these cool pockets are over-ridden by the warm waters as in the 1982 – ’83 ENSO, the fishes die en masse. The other alternativeis for the shoals to migrate to cooler deeper waters (below 100 m) or to the southern Peruvian orChilean coasts. In the deeper waters the low productivity will not sustain such huge populationsleading to mass mortality. In the southern waters the established South American pilchard populationsheavily compete with migrating anchovies again leading to large scale mortality.OverfishingVulnerability to these harsh environmental conditions may have been enhanced by the heavy fishingpressure of the late 1960s up to 1970. In fact studies have shown that even before the impact of 1972-’73ENSO, there was a recruitment collapse in the stocks, the total biomass estimated to be 9 – 14 m t in 1971.In 1966 the Maximum Sustainable Yield (MSY) was estimated to be 8.0 m t, which was revised as 9.5 m tin 1970.Predation and CompetitionAnother interesting aspect is the heavy predation on the anchovy populations by the guano birds.Nearly 80 – 95% of their diet consists of the anchovies.  So the huge bird populations (estimates as high as30 million) before the industrial fishery has now dwindled to as low as 5 million, mainly due to the fluctuationsin the anchovy populations. Another major predator is the Chilean jack mackerel (Trachurus murphyi),whose population increases during the El Nino years due to enhanced spawning success.   During El Ninoyears other predators like the yellowfin tuna, dolphinfish and Chilean bonito migrate southward to theCMFRI - Winter School on Impact of Climate Change on Indian Marine Fisheries 55Peruvian anchovy fishery; Factors affecting the resourceanchovy domain. So the trophic dynamics is greatly affected by these events. Competition with the SouthAmerican pilchard especially when the anchovies migrate southwards is another major factor. The pilchardpopulations are not much affected by the El Nino. The inverse relationship between the two tandem fisheriescan be clearly seen in the figure. After the 1972-’73 ENSO, the pilchard stock began to increase and animportant fishery developed over the next 15 years coinciding with the decline and rebuild of the anchovyfishery.Management  In 1963, the Instituto del Mar del Peru (IMARPE) was established with a strong FAO backing tostudy the fishery and to advise the Government. In 1965 a five-day week fishing was established. In 1966three months of closed season (veda) was put in place during January to March. Catch quotas were fixed asper the MSY levels (8.0 – 9.5 m t). So a second closed season was envisaged after around six months fishingwhen the quota would be taken. But many of these measures were hard to implement. It is now estimatedthat only less than 1500 vessels are required to catch around 10 m t of anchovies.The Peruvian anchovy fishery is one example to understand how the climate and environment influencethe fisheries. Another interesting parallel is the story of a warm-water species (Sardinops melanosticta –Japanese pilchard) and the impact of cool-water incursion into its domain in the Northwest Pacific fishingarea.

Peruvian anchovy fishery:

factors affecting the resource

 -Winter School on

Impact of Climate Change on Indian Marine Fisheries held at CMFRI, Cochin 18.1.2008 to 7.2.2008

Peruvian anchovy fishery: factors affecting the resource -Winter School on Impact of Climate Change on Indian Marine Fisheries held at CMFRI, Cochin 18.1.2008 to 7.2.2008

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