Page 25 - World Aquaculture Magazine - March 2011

World Aquaculture 23
and cages, especially in freshwater reservoirs, have been test-
ed, and preliminary culture results have shown promising
results. Although the growth potential of the tilapia culture
industry in RN is bright, commercial initiatives are still to
be consolidated.
It is interesting to acknowledge the aquaculture potential
of freshwater reservoirs throughout the state for growing
tilapia, carp, as well as other fish species. The three largest
dams in RN have a capacity for accumulated water of more
than 3 billion m3 and the total capacity in the state – over
300 reservoirs of various sizes – exceeds 5 billion m3. Such
freshwater reservoirs were constructed in RN to minimize
the severe effects of heavy droughts, a common feature in
hot and semi-arid northeastern Brazil, but their aquaculture
use is still emerging.
Marine fish
There is no commercial marine fish culture in RN. How-
ever, there are several families of marine fishes potentially
suitable for cultivation in the state’s marine and estuarine
waters. Among them are Carangidae, Centropomidae, Ger-
reidae, Lutjanidae, Mugilidae, Rachycentridae, Scombridae,
Serranidae and Sparidae. The Lutjanids, for example, are
relatively abundant in coastal waters and includes such spe-
cies of commercial importance as Lutjanus synagris, L. jocu,
L. buccanella, L. purpureus, L. analis and L. griseus. A further
step has already be taken regarding the Rachycentridae as re-
search on reproduction and larval rearing of cobia (Rachycen-
tron canadum) is currently underway at Aquatec Ltd. (www.
aquatec.com.br) in Barra de Cunhaú (6º22’S, 35º07’W), a
leading commercial shrimp hatchery in Brazil. Culture of co-
bia in earthen ponds is also underway at Camanor (www.ca-
manor.com.br) in Barra de Cunhaú and in Guamaré (5º06’S,
36º19’W), and at Universidade Federal Rural do Semi-Árido
(UFERSA) in Mossoró (5º11’S; 37º20’W).
Seaweed
RN has a high diversity of seaweed, which comprises at
least 51 taxa, distributed in 13 species of Chlorophyta (five
orders and seven families), eight species of Phaeophyta
(three orders and three families) and 30 species of Rhodo-
phyta (six orders and 11 families; Marinho-Soriano 1999).
The red seaweeds of the Gracilaria genus are particularly
abundant and harvested from natural beds by fishermen for
agar extraction. Among the different species tested in RN
for cultivation, Gracilaria spp. have been the most interest-
ing candidates (Marinho-Soriano et al. 2002, 2009, Bezerra
and Marinho-Soriano 2010).
Molluscs
Organic culture of edible oysters (Crassostrea brasiliana)
through the rack and tray method has been successfully car-
ried out at Primar Aquaculture (www.primarorganica.com.
br) in Tibau do Sul (6º11’S, 35º05’W). In addition, experi-
mental work on larval technology relative to Crassostrea
brasiliana has been conducted at Larvi Aquicultura e Pro-
jetos Ltd. near Macau (5º6’S, 36º38’W). Other potential in-
digenous shellfish for cultivation in RN are Mytella charru-
Aerial view of rustic shrimp farming ponds in RN. (Photo by
Alexandre A. Wainberg)
The red seaweeds of the Gracilaria genus are interesting
candidates for aquaculture in RN. (Photo by Eliane Marinho-
Soriano)
Oyster (Crassostrea brasiliana) spat collectors. (Photo by
Alexandre A. Wainberg)