|Low nutrient availability is not the single factor limiting Artemia cyst productivity in salinas of NE-Brazil|
|Camara, M.R.; Tackaert, W. (1994). Low nutrient availability is not the single factor limiting Artemia cyst productivity in salinas of NE-Brazil, in: Koop, K. (Ed.) (1994). Ecology of Marine Aquaculture: a Workshop on Research in Aquaculture. pp. 59-76|
|In: Koop, K. (Ed.) (1994). Ecology of Marine Aquaculture: a Workshop on Research in Aquaculture. International Foundation for Science: Stockholm. 161 pp., more|
|Also published as |
- Camara, M.R.; Tackaert, W. (1994). Low nutrient availability is not the single factor limiting Artemia cyst productivity in salinas of NE-Brazil, in: (1994). IZWO Coll. Rep. 24(1994). IZWO Collected Reprints, 24: pp. chapter 4 [Subsequent publication], more
Aquaculture; Marine ecology; Artemia Leach, 1819 [WoRMS]; Brazil [gazetteer]; Marine
Artemia production in NE-Brazil began in 1977 after a successful inoculation of Artemia franciscana (San Fransisco Bay, California, USA) in solar salt ponds in Macau (RN state) and was followed by a rapid natural dispersion of this crustacean to all saltwork areas in the region. Artemia is basically produced in extensive conditions as an opportunistic by-product collected from salt evaporation ponds. This type of approach has, however, brought about very unpredictable results, as is reflected in a drastic decline of cyst production occurring from 1982 onwards. Low nutrient concentrations and a drop in primary productivity have been suggested as possible causes for this decline. In order to provide a better characterisation and understanding of these hypersaline environments, comparative ecological data were collected from artisanal salinas as well as highly mechanised salt operations. Artemia franciscana was present at all sites and was found to survive, mature, and reproduce at temperatures as high as 38°C. Cyst production in these biotopes was, however, negligible to low. In all studied habitats, nutrient levels (P-PO4; N-NO2; N-NO3) in medium to high salinity evaporation ponds showed little variation and were found to be low. Except for rain precipitation, little variation was found among biotypes for other parameters monitored (T°C; D.O.; pH; Salinity; Transparency).
On the whole, Artemia cyst production seemed to be more dependent on simple management procedures, such as routine inoculations (nauplii and adults), rather than only on the low levels of nutrients found. It is postulated that Brazilian Artemia has gradually lost its ability for cyst reproduction as a result of (genetic?) adaptation to the year-round favourable conditions of the environment. Management strategies, including re-inoculation of a strain which has previously shown good cyst production characteristics (e.g., San Fransisco Bay or "old Macau") and application of salinity shocks, are proposed in order to revive cyst production in NE-Brazil.