140
P. Lana eta!.
More than 300 bird species have been recorded for the coastal plain ofParanagua Bay. Pelecaniformes, Ciconiiformes, Anseriformes, Falconiformes,
Charadriiformes and Coraciiformes comprise about 90 o/o and Passeriformes approximately 10 o/o of the bird fauna. Residents comprise 52.6 o/o of
the species, the others are migratory species from the northern hemisphere
or from sub-antarctic and antarctic regions of the southern coast of South
America. Frigate birds (Fregata magnificens), brown boobies (Sula leucogaster) and common gulls (Larus dominicanus) are the most frequent and
abundant forms in estuarine waters ( V. Moraes and R. Krul, pers. comm.).
The gray dolphin Sotalia fluviatilis is the most common marine mammal in the bay, followed by scarce records of the franciscana Pontoporia
blainvillei. Both are neritic species that appear throughout the year in
coastal waters of Parana State. Other neritic species, like Tursiops truncatus
and Steno bredanensis, occur at lower densities in adjacent shelf waters.
Oceanic odontocetes, including Delphinus capensis, Stenella frontalis and,
less frequently, Kogia simu, Ziphius cavirostris and Orcin us orca, have been
recorded stranded along the coast of Parana State and in the euhaline sector of the bay (F. Rosas, pers. comm.). Several pinnipeds, like Arctocephalus
tropicalis in winter and the rare Arctocephalus australis and Mirounga leonina, visit the bay and adjacent coastal waters, while large whales (i.e.
Balaenoptera edeni, Eubalaena australis, Megaptera novaeangliae) have
been recorded along the Parana coast.
10.4 Trophic Structure and Energy Flow
Detrital material from phytoplankton and from riverine and terrestrial
sources is associated with salinity gradients, while detrital material from
marshes, mangroves and other wetlands is associated with a lateral gradient. The pronounced variability of POC:Chl-a ratios, with peaks in
autumn/winter and low values in warm rainy periods, suggests that plant
debris from mangroves and marshes as the dominant source of organic
detritus (Brandini 1985) is replaced by phytoplankton in summer (Machado et al. 2000). Among others, phytoplankton productivity in Paranagua
Bay is controlled by light, nutrient and seston gradients. In contrast to
nutrient-rich but turbid waters in oligohaline and low-nutrient, hightransparency waters in euhaline areas (Brandini et al. 1988), maximum
productivity rates and low carotenoid:chlorophyll-a ratios indicate that
light and nutrients provide optimal conditions for algal growth in mesohaline areas of the bay, though photoinhibition may occur at high irradiance
levels during summer (Brandini 1985). In general, the grazing impact of
P. Lana eta!.
More than 300 bird species have been recorded for the coastal plain ofParanagua Bay. Pelecaniformes, Ciconiiformes, Anseriformes, Falconiformes,
Charadriiformes and Coraciiformes comprise about 90 o/o and Passeriformes approximately 10 o/o of the bird fauna. Residents comprise 52.6 o/o of
the species, the others are migratory species from the northern hemisphere
or from sub-antarctic and antarctic regions of the southern coast of South
America. Frigate birds (Fregata magnificens), brown boobies (Sula leucogaster) and common gulls (Larus dominicanus) are the most frequent and
abundant forms in estuarine waters ( V. Moraes and R. Krul, pers. comm.).
The gray dolphin Sotalia fluviatilis is the most common marine mammal in the bay, followed by scarce records of the franciscana Pontoporia
blainvillei. Both are neritic species that appear throughout the year in
coastal waters of Parana State. Other neritic species, like Tursiops truncatus
and Steno bredanensis, occur at lower densities in adjacent shelf waters.
Oceanic odontocetes, including Delphinus capensis, Stenella frontalis and,
less frequently, Kogia simu, Ziphius cavirostris and Orcin us orca, have been
recorded stranded along the coast of Parana State and in the euhaline sector of the bay (F. Rosas, pers. comm.). Several pinnipeds, like Arctocephalus
tropicalis in winter and the rare Arctocephalus australis and Mirounga leonina, visit the bay and adjacent coastal waters, while large whales (i.e.
Balaenoptera edeni, Eubalaena australis, Megaptera novaeangliae) have
been recorded along the Parana coast.
10.4 Trophic Structure and Energy Flow
Detrital material from phytoplankton and from riverine and terrestrial
sources is associated with salinity gradients, while detrital material from
marshes, mangroves and other wetlands is associated with a lateral gradient. The pronounced variability of POC:Chl-a ratios, with peaks in
autumn/winter and low values in warm rainy periods, suggests that plant
debris from mangroves and marshes as the dominant source of organic
detritus (Brandini 1985) is replaced by phytoplankton in summer (Machado et al. 2000). Among others, phytoplankton productivity in Paranagua
Bay is controlled by light, nutrient and seston gradients. In contrast to
nutrient-rich but turbid waters in oligohaline and low-nutrient, hightransparency waters in euhaline areas (Brandini et al. 1988), maximum
productivity rates and low carotenoid:chlorophyll-a ratios indicate that
light and nutrients provide optimal conditions for algal growth in mesohaline areas of the bay, though photoinhibition may occur at high irradiance
levels during summer (Brandini 1985). In general, the grazing impact of