The leeches of the Lagoa de Antela

Among the forgotten pieces of the history of the Lagoa de Antela are the leeches (sambesugas): the blood-sucking worms that, in the 19th century, doctors across Europe used for bloodletting. The lagoon was one of the most prized breeding grounds in Spain, and its loss figures among the harms the neighbours attributed to the draining.

Why so many leeches were wanted

The French physician François Joseph Victor Broussais argued in the 19th century that all diseases began in the gastrointestinal tract and were cured by removing the "harmful" blood with leech bloodletting. His theory triumphed so thoroughly from France that demand soared and the resource was over-exploited in several places in the peninsula, among them the Lagoa de Antela ^[1]. The "leech fever" peaked in 1832 and France came to import more than 57 million specimens ^[1].

A study by the University of Santiago de Compostela, in collaboration with that of Cádiz, published in the journal Medical History by Damián Copena and María Gómez-Martín, analyses this Spanish-French trade, from collection and regulation to commercial relations with France up to 1860 ^[1].

The Antela factory

According to that work, a factory was set up at the Lagoa de Antela that left "for the French as much profit as tuna could in the Conil tuna traps". The French paid four reales per pound for leeches (thirty to forty dozen), and in the north-west of the peninsula the reference place for collection was Ourense. Copena sums up that it was a very lucrative activity for the French and not so much for the Galicians ^[1].

Regulation and ban

The over-exploitation led the Government, on the basis of information from the Subdelegation of Medicine, Surgery and Pharmacy of Santiago de Compostela, to consider it necessary to control the populations. A two-year pause and an exclusive catching season were established, with a ban on collecting leeches in March, April and May, the breeding period. The measure finally applied only in Galicia, the most affected area ^[1].

The source attributes to Copena that in 1827 Galicia became the first territory to ban extraction, and the same article places in 1839 the ban on catching the annelid, complemented by measures to increase populations ^[1]. According to the study, in Galicia catches did not exhaust the resource, and from 1850 the peninsula ceased to be a supplier and began importing leeches; from 1860 the therapy was replaced by others with a scientific basis ^[1].

The lost breeding ground

The SGHN records, from Eduardo Rico Boquete’s study of the draining projects (2008), that on 26 March 1848 the resident José Pinal submitted a petition to the provincial political government denouncing the harm of draining part of the lagoon, among them the destruction of the "breeding ground of the best leeches Spain possessed" ^[3]. When the 19th-century projects multiplied, the neighbours opposed them partly because they lost grazing, fishing and leech-gathering land ^[2].

The false malaria endemic

To justify the draining, from the 18th century it was spread that Antela was a "pool of infections and great stenches" and the idea circulated that it caused endemic malaria, which the source calls false ^[2]. Canon Bedoya, in 1831, asked that the "sad water" of the lagoon should not close off to A Limia the way to the "fields of its happiness" ^[2]. The full history of the projects is in The draining of the Lagoa de Antela.

Gciencia recalls that, according to the anthropologist Olalla López Costas, malaria (the "tertian fevers") was common in Galicia until the 19th century, linked to shallow stagnant water, and that some theories place malarial fevers among the reasons for draining the Lagoa de Antela. In his Memoria sobre el desagüe de la laguna Antela ó de la Limia (1831), Bedoya asked that the intermittent fevers he attributed to the "harmful pool" cease to be so common ^[4].

Links

• Lagoa de Antela
• The original lagoon
• The draining of the Lagoa de Antela

Sources

1. Gciencia, «As sambesugas, as ‘curandeiras’ do século XIX que se cultivaron na Lagoa de Antela» (sobre Copena e Gómez-Martín, Medical History). https://www.gciencia.com/medioambiental/sambesugas-curandeiras-seculo-xix-se-cultivaron-lagoa-antela/
2. Gciencia, «A falsa endemia de malaria e outros intentos para desecar a lagoa de Antela». https://www.gciencia.com/medioambiental/falsa-endemia-malaria-outros-intentos-desecar-lagoa-antela/
3. Sociedade Galega de Historia Natural, «Intentos de desougamento da Lagoa de Antela». https://sghn.org/intentos-desougamento-lagoa-antela/
4. Gciencia, «Cando a malaria era unha doenza común en Galicia». https://www.gciencia.com/retro/cando-a-malaria-era-unha-doenza-comun-en-galicia/