The phenomenon peaked in the late afternoon of Monday, 2nd, but there were still specimens dying between Tuesday and this Wednesday, 4th.
Thousands of freshwater shrimp died and accumulated on a small beach on the Tietê River, in Igaraçu do Tietê, in the interior of São Paulo. The phenomenon peaked in the late afternoon of Monday, the 2nd, but there were still specimens dying between Tuesday and this Wednesday, the 4th. The Environmental Company of the State of São Paulo (Cetesb) sent a team to the site and collected samples of the water and shrimp for analysis.
According to Juarez Sbeghen, responsible for the municipality’s inspection sector, the pitus, as freshwater shrimp are known, began to accumulate in the small beach around 5pm on Monday. “We had already seen fish deaths, which are quite common, but shrimp deaths had never happened. Technicians from our Department of the Environment and Cetesb are investigating what happened,” he said.
Initially, according to him, the shrimp only appeared dead on the beach. “We later found that they were also accumulating on the banks, along the river. Only at the beach we collected two trucks of shrimp mixed with sand. The material has already been sent to the Barra Bonita landfill, as per Cetesb’s instructions”, he says.
The Macrófitas Group, made up of representatives from civil society, boat operators on the Tietê and experts, created to discuss pollution in the river in the Barra Bonita region, is also investigating what happened. “It is noteworthy that there were only shrimp deaths, occasionally only on Igaraçu Beach, and no other species were affected”, he says in a note.
According to Macrófitas, the shrimp deaths in the Tietê River may be associated with organic pollutionthe reduction of oxygen dissolved in water, eutrophication, chemical discharges and sudden environmental variations. “These events reflect the fragility of the ecosystem and highlight the need for strict control of pollution sources and integrated management of the river”, he says.
Cetesb reported that its technicians inspected the little beach of Igaraçu do Tietê on the afternoon of Tuesday, 3rd, as soon as the complaint came to their attention, and collected samples that will be analyzed in the laboratory. The agency also said that it is investigating the possible causes of the occurrence and advises that the population does not fish or bathe in this location.
The little beach is close to the Barra Bonita hydroelectric dam. The dam operator, Auren Energia, says there is no relationship between the preventive maintenance of the lock at the Barra Bonita Hydroelectric Plant and the appearance of freshwater shrimp in Igaraçu do Tietê. As soon as it became aware of the situation, even though there was no connection with the operation of HPP Barra Bonita, the company informed Cetesb and made itself available to support environmental agencies in investigating the case.
Freshwater shrimp, from the genus Macrobrachium, known as pitu, have a similar flavor to marine shrimp. The species is native to the lake regions of the southeastern United States, but occurs as far south as Brazil, and its presence in running waters is common.
