Bottom farming

About 80 percent of Peruvian scallop farmers use bottom farming, as this method doesn’t need big investments like the hanging pearl net method. Scallops farming in Peru is a completely natural process and occurs in deeper water between 5 to 40 meters, 6 to 10 miles out of the coast. There are three main areas for scallop farming: i) the Sechura region (Piura) where around  75% of national production takes place, ii) the Guaynumá area where 20 percent of the national production takes place, principally by the company Acuapesca, iii) the Pisco area contributing the last 5 percent. There are no differences between farming methods between these three regions, and in all areas, bottom farmers can seed and harvest at any time of the year. Although, most farmers try to reach the most demanded sizes of 20-30/lb and some 10-20/lb shell off at around September in light of the upcoming Christmas period.

Key features
Average stocking density

Depends on climate and water conditions at any time

Average productivity

Depends on climate and water conditions at any time

# of crops per year


# of days per crop

About 1 year, depending on climate and water conditions

Harvesting season

All year round with commercial peak around September

Type of farmer

Small and medium-scale farmers

Potential risks
  • Climate and temperature changes
  • Entry of diseases
  • Entry of waste
  • Submarine currents
  • Natural predators

Type of farmers

Most scallop farmers operate in the northern part of Peru, in the Bay of Sechura, close to Piura city. This Bay of Sechura is divided by the Peruvian authorities into about 100 concessions or ‘designated’ farming areas. The government has given these concessions ‘in use’ for a period between 10 and 30 years to fishermen, companies and associations of farmers. One condition is that a concession holder must use the designated area for scallop farming. Moreover, there is a minimum production volume each year for each concession which are different in size. If a farmer doesn’t reach the minimum volume, depending on the actual natural conditions, the authorities might decide to withdraw the concession. Some bigger farmers like Iprisco have several concessions and use them all for their own production. However, a concession holder is also allowed to let the designated area (or part of it) to a third party. Consequently, it is possible that there are 20 smaller farmers operating on only one concession. Each ‘user’ is free to choose his way of farming: bottom or hanging.

About 30 percent are medium-scale farmers who need public processing plants for their exports. 50 Percent of all farmers do not export themselves nor have their own hatchery and production facility but sell their product directly to the bigger farmers and trading companies. Due to the concession method of the Peruvian authorities, there are associations of farmers. Some concessions are too big for only one concession holder and he might prefer to let it to several smaller farmers. These farmers work together in things like input supply, security, harvesting and trading. In lots of cases the concession holder takes care of these topics in the name of all the smaller farmers together, in exchange for a fixed amount of money before stocking.

Production and harvesting system

With scallop bottom farming, after stocking the larvae, there is nothing more to do then to wait for 8-14 months until the scallops to have reached commercial size. During harvest the scallops are being caught by hand and bag by divers and brought to small boats. From there, the bags with scallops are brought to shore without ice for immediate primary processing.

Target species and byproducts

Peruvian scallop farmers use monoculture. Sometimes there is some bycatch of mussels and other bivalves, but these are not fit for export purposes.

Stocking densities and productivity

Normally stocking is done manually. The larvae are deposited at the bottom of the sea, protected by rocks from strong currents. At this stage, the stocking density depends on various factors like the direction of ocean currents, seawater temperature at various depths, alga, salinity, water pollution, etc. In addition, it is important to do an analysis of the actual biomass in a specific part of the concession before stocking: higher biomass implies higher food availability, thus the stocking density can be high(er). Vice versa: lower biomass implies lower food availability which means low(er) stocking densities. Consequently, also, productivity per hectare depends heavily on the climate and conditions of the sea water. Sometimes one needs only 6 months to reach a 20-30 kg shell but also a grow-out time of 18 months is not rare. It all depends on the natural resources without any possibility of human intervention to speed up productivity.

Use of seed, feed and other inputs

There are two ways of getting the larvae: from natural resources or from hatcheries/laboratories for reproduction. Larvae collected from the natural environment are picked by hand by divers. These larvae have a size of about 200μm. In 2015 and 2016 there was a great lack of larvae due to overfishing of natural resources, especially from Isla de Lobos de Tierra. Farmers even wanted to invade national parks like Paracas for the larvae, which the Peruvian government ultimately refused. Consequently, scallop production dropped considerably during these years. Slowly these natural resources are recovering, but the authorities still control as much as possible of the catch of larvae in these areas. Larvae purchased from a hatchery have an average size of 700μm. These laboratories use mature scallops as broodstock for reproduction. The company Acuapesca has its own hatchery for its own farm, but also sells larvae to small and medium-scale farmers. Small private hatcheries that are operating without farms also exist. Moreover, the Peruvian government is investing in creating public hatcheries for the scallop farming industry. Public projects like CITE Sechura in cooperation with the University Cayetano Heredia are trying to supply larvae in a more sustainable way in near future.

No feed is used during farming, the sea takes care for all available feed. In periods of less natural biomass, there are fewer possibilities for scallop farming. In periods of lots of natural biomass, one can seed more larvae and reach higher production levels. As there are no fixed seasons of high or low biomass, it is necessary to do analysis of the sea water continuously. There is no input of medicines or probiotics.


Stocking, harvesting and trading is done year-round in all areas. There is a peak of harvesting in September due to the upcoming Christmas season.