Ecological threats to Artemia franciscana populations in the coastal saltworks of Rio Grande do Norte, NE-Brazil Marcos R. Camara UFRN.

Ecological threats to Ecological threats to Artemia franciscanaArtemia franciscana populations in the coastal saltworks of Rio populations in the coastal saltworks of Rio Grande do Norte, NE-BrazilGrande do Norte, NE-Brazil

Marcos R. Camara

UFRN

BackgroundBackground

The genus Artemia is a complex of sibling species and superspecies defined by the criterion of reproductive isolation.

Two bisexual species are represented in the New World: Artemia persimilis Piccinelli & Prosdocimi and

Artemia franciscana Kellogg.

BackgroundBackground

Artemia persimilis is restricted to some localities in Argentina and Chile.

Artemia franciscana is endemic to the Americas and the Caribbean, with various populations established in South American countries, either by deliberate inoculation or natural dispersal.

BackgroundBackground

Artemia franciscana is found in NE-Brazil as a result of inoculations made in Macau (RN) in 1977 with cysts from a SFB stock.

BackgroundBackground

Artemia franciscana cysts have been dispersed to neighboring saltworks by men (for

aquacultural purposes and to aid in salt production), by wind and by local waterfowl.

Electrophoretic evidence confirmed the proposed origin, from SFB cysts, of the Macau population (Gajardo et al., 1995).

Shrimp culture in NE-BrazilShrimp culture in NE-Brazil

The recent expansion of Litopenaeus vannamei culture in NE-Brazil has required increasing quantities of land, postlarvae and feeds, among other resources.

Brazilian yearly production of Brazilian yearly production of Litopenaeus Litopenaeus vannameivannamei postlarvae (PL) and estimated postlarvae (PL) and estimated consumption of consumption of ArtemiaArtemia cysts and biomass in the cysts and biomass in the period 1994-2002period 1994-2002

Year

199419951996199719981999200020012002

PL(x 106)

499565673

1,0001,5002,9685,0267,91514,698

Cysts(ton.)

0.40.50.61.01.52.95.07.914.6

Biomass(ton.)

7.58.510.015.022.544.575.4118.8220.5

Artemia in NE-BrazilArtemia in NE-Brazil

In order to cope with the growing demand for Artemia in NE-Brazil, harvesting pressure has dramatically increased and (re)inoculations are now common practices in the saltworks of RN.

Artemia in NE-BrazilArtemia in NE-Brazil

The (over)exploitation of cysts and biomass in a reduced harvesting area (several hundred hectares of saltworks have recently been converted to shrimp grow-out ponds) and the risk of unaccountable and non-intentional inoculations are threats to the sustainable use and biodiversity of Artemia franciscana populations in NE-Brazil.

What is biodiversity?What is biodiversity?

Biodiversity has been defined as the total complexity of all life, including not only the great variety of organisms but also their varying behavior and interactions.

From this viewpoint, no single objective measure of biodiversity is possible, only measures relating to particular purposes or applications.

A measure of biodiversity should quantify a value that is both broadly shared among the people for whom they are acting and considered as being in need of protection.

Biodiversity valueBiodiversity value

• One broadly shared value for conserving wholesale biodiversity lies in ensuring continued possibilities both for adaptation, and for future use by people in a changing world.

• Biologists, for example, have argued that this value in biodiversity is likely to be associated with the variety of different genes that can be expressed by organisms as potentially useful phenotypic traits or characters.

Biodiversity valueBiodiversity value

Because we do not know yet precisely which genes or characters will be of value in the future...

1. They must all be treated as having equal value.

2. The greatest value for conservation will come from ensuring the persistence of as

many different genes or characters as possible, as a form of insurance.

Biodiversity and sustainable use of Artemia in NE-Brazil A strategic approach is needed to assess current

Artemia practices in NE-Brazil. It should include:

1. Reduction of harvesting pressure in local saltworks.

2. Mitigation of the risks associated with non-intentional inoculations.

3. Genetic characterization of local Artemia franciscana populations.

Genetic diversityGenetic diversity

• A currency of value for conserving the wholesale biodiversity of Artemia franciscana populations in NE-Brazil.