The Subtropical Estuarine Complex of Paranagua Bay, Brazil
139
na acutifrons) are found in salinities as low as 15, they occur mainly in
euhaline areas under the influence of coastal waters. Marine stenohaline
species of warm coastal and shelf waters, like Paracalanus indicus, Clausocalanus furcatus, Temora stylifera, Oithona plumifera, Oncaea venusta,
Corycaeus amazonicus and C. giesbrechti, appear in the outer bay. Low densities of subtropical species ( Centropages brachiatus, Oncaea conifera) in
the outer bay (Montu and Cordeiro 1988) suggest the addition of cold
nutrient-rich coastal waters during winter.
The importance of bacteria (Kolm et al. 1987), harpacticoid copepods,
foraminifera (Disar6 1995) and mangrove oligochaetes and nematods
(Blankensteyn 1994) in microbenthic and meiobenthic associations of
Paranagua Bay is virtually unknown. Despite similar sediment characteristics in salt marshes, mangroves and non-vegetated flats, the composition
and abundance of the macrobenthic fauna can vary widely among suband intertidal bottoms in euhaline and polyhaline regions of the bay (Lana
1986, 1994; Blankensteyn 1994; Netto and Lana 1996, 1997b; Couto 1996;
Lana et al. 1997; FUNPAR 1997). While salinity and environmental energy
gradients appear to control large-scale distribution patterns in the bay,
plant architecture and food availability seem to be the main source of
small-scale macrofauna! variability (Lana and Guiss 1991, 1992; Lana et al.
1997). In contrast to maximum abundance of invertebrates in temperate
latitudes during late spring and early summer, benthic invertebrate populations in Paranagua Bay lack any pronounced seasonal pattern, with high
abundance both in summer and winter. Seasonal oscillations have been
attributed to variations in plant cover and biomass, rainfall, low temperature, or predation rates.
At least 200 species of fish (66 commercially important) and about 40
larval types have been described for Paranagua Bay (Correa 1987; FUNPAR 1997). On the basis of migratory behavior, the commercially important species, which reproduce mainly in spring and summer, can be divided into four categories. Marine species, like the mullets Mugilliza and M.
platanus (Mugilidae) and the sea catfish Netuma barba (Ariidae), visit the
estuarine system for spawning while others, such as the pompanos Trachinotus carolinus and T. falcatus (Carangidae), explore the bay as a feeding
and growing site. Estuarine and coastal species, like the weakfish Cynoscion leiarchus, C. acoupa and the white mouth croaker Micropogonias furnieri (Sciaenidae), migrate to oceanic waters for spawning and early development but return to the bay as juveniles and adults. Finally, the catfish
Cathorops spixii and Sciadeichthyes luniscutus (Ariidae), the snook Centropomus parallelus (Centropomidae), the southern king croaker Menticirrhus americanus (Sciaenidae), and the mullets Mugil curema and M. gaimardianus are resident estuarine species (Correa 1987).
139
na acutifrons) are found in salinities as low as 15, they occur mainly in
euhaline areas under the influence of coastal waters. Marine stenohaline
species of warm coastal and shelf waters, like Paracalanus indicus, Clausocalanus furcatus, Temora stylifera, Oithona plumifera, Oncaea venusta,
Corycaeus amazonicus and C. giesbrechti, appear in the outer bay. Low densities of subtropical species ( Centropages brachiatus, Oncaea conifera) in
the outer bay (Montu and Cordeiro 1988) suggest the addition of cold
nutrient-rich coastal waters during winter.
The importance of bacteria (Kolm et al. 1987), harpacticoid copepods,
foraminifera (Disar6 1995) and mangrove oligochaetes and nematods
(Blankensteyn 1994) in microbenthic and meiobenthic associations of
Paranagua Bay is virtually unknown. Despite similar sediment characteristics in salt marshes, mangroves and non-vegetated flats, the composition
and abundance of the macrobenthic fauna can vary widely among suband intertidal bottoms in euhaline and polyhaline regions of the bay (Lana
1986, 1994; Blankensteyn 1994; Netto and Lana 1996, 1997b; Couto 1996;
Lana et al. 1997; FUNPAR 1997). While salinity and environmental energy
gradients appear to control large-scale distribution patterns in the bay,
plant architecture and food availability seem to be the main source of
small-scale macrofauna! variability (Lana and Guiss 1991, 1992; Lana et al.
1997). In contrast to maximum abundance of invertebrates in temperate
latitudes during late spring and early summer, benthic invertebrate populations in Paranagua Bay lack any pronounced seasonal pattern, with high
abundance both in summer and winter. Seasonal oscillations have been
attributed to variations in plant cover and biomass, rainfall, low temperature, or predation rates.
At least 200 species of fish (66 commercially important) and about 40
larval types have been described for Paranagua Bay (Correa 1987; FUNPAR 1997). On the basis of migratory behavior, the commercially important species, which reproduce mainly in spring and summer, can be divided into four categories. Marine species, like the mullets Mugilliza and M.
platanus (Mugilidae) and the sea catfish Netuma barba (Ariidae), visit the
estuarine system for spawning while others, such as the pompanos Trachinotus carolinus and T. falcatus (Carangidae), explore the bay as a feeding
and growing site. Estuarine and coastal species, like the weakfish Cynoscion leiarchus, C. acoupa and the white mouth croaker Micropogonias furnieri (Sciaenidae), migrate to oceanic waters for spawning and early development but return to the bay as juveniles and adults. Finally, the catfish
Cathorops spixii and Sciadeichthyes luniscutus (Ariidae), the snook Centropomus parallelus (Centropomidae), the southern king croaker Menticirrhus americanus (Sciaenidae), and the mullets Mugil curema and M. gaimardianus are resident estuarine species (Correa 1987).