Neotropic Cormorant Phalacrocorax Brasilianus Research Articles

Redescription and molecular characterization of Baruscapillaria spiculata (Nematoda: Capillariidae) parasitizing the Neotropic cormorant Phalacrocorax brasilianus from two Argentinian lagoons.

Two species of intestinal Capillariidae were hitherto known from the Neotropic cormorant Phalacrocorax brasilianus, Baruscapillaria spiculata (Freitas, 1933), and Baruscapillaria appendiculata (Freitas, 1933). The original descriptions are very short and brief, and further reports of both species are scarce and/or confusing. This paper provides a morphological redescription and molecular characterization, based on the partial 18S rDNA gene, of B. spiculata specimens parasitizing the Neotropic cormorant in two continental lagoons from Buenos Aires province, Argentina. Both morphological and morphometrical differences between B. spiculata and B. appendiculata are highlighted on the examination of available type material. Additionally, two previous reports of B. appendiculata from Mexico and Brazil are discussed. A phylogenetic analysis conducted on specimens of B. spiculata and 46 other capillariid isolates available from the GenBank demonstrated a sister-taxon relationship between our specimens and the type species of Baruscapillaria. But, at the same time, significant genetic distances between both taxa showed an interesting variability of the genus Baruscapillaria. The probable division of this genus into multiple genera could probably be confirmed through integrative studies including more species.

Ensamble de aves en una mitilicultura de Chiloé, sur de Chile

We evaluated the composition and seasonal variation in the diversity of an aquatic bird assemblage related to a mussel farm in southern Chile. Observations were carried out during spring 2008, and the summer, autumn and winter of 2009. Neotropic cormorant Phalacrocorax brasilianus, followed by kelp gull Larus dominicanus and imperial cormorant P. atriceps were the dominant species. We identified five dietary groups, of which piscivorous birds had the greatest representation. Finally, we discuss the need to evaluate the potential impacts generated by the intensive mussel farming on various components of the marine ecosystem in southern Chile.

Genetic and Morphological Evidences for the Existence of a New Species of Contracaecum (Nematoda: Anisakidae) Parasite of Phalacrocorax brasilianus (Gmelin) From Chile and Its Genetic Relationships with Congeners From Fish-Eating Birds

Contracaecum australe n. sp. is described from the Neotropic cormorant Phalacrocorax brasilianus in Chile based on morphology and the sequence analyses of multiple loci, i.e., mitochondrial cytochrome oxidase 2, mtDNA cox-2, the small subunit of the mitochondrial ribosomal RNA gene, rrnS, and the ITS-1 and ITS-2 regions of nuclear ribosomal DNA. Moreover, sequence analysis of the same genes was carried out on the morphospecies Contracaecum chubutensis Garbin et al. (2008) from Phalacrocorax atriceps. Further, genetic relationships are presented between C. australe n. sp. and C. chubutensis with respect to the related congeners from fish-eating birds previously characterized genetically on the same genetic markers, i.e., Contracaecum rudolphii A, B, C, D, and E, Contracaecum septentrionale, Contracaecum microcephalum, Contracaecum bioccai, Contracaecum pelagicum, Contracaecum micropapillatum, Contracaecum gibsoni, and Contracaecum overstreeti. Several phylogenetic analyses (MP, NJ, and BI) inferred from mitochondrial genes (cox-2 , rrnS) were congruent in depicting C. australe n. sp. and C. chubutensis as forming distinct clades, highly supported, from the remainder of the Contracaecum taxa considered; thus, it validates their specific status. Further, analyses of the ITS-1 and ITS-2 sequence data of C. australe n. sp. and C. chubutensis supported their distinction with respect to the 2 sibling species, C. rudolphii D and C. rudolphii E, previously detected from Phalacrocoracidae of Australia. Morphological analysis and the differential diagnosis of male specimens of C. australe n. sp. enabled the detection of differences in a number of characters, including spicule length, peculiar shape of male tail, paracloacal papillae disposition, and shape and bifurcation depth of interlabia. According to the genetic and morphological results obtained, the erection of a new taxon from fish-eating birds of the Austral region is given and its formal description is presented. Phylogenetic trees support both C. australe n. sp. and C. chubutensis as being included in the same clade with the previously detected species from cormorants, i.e., C. rudolphii A, B, C, and C. septentrionale. The finding of C. australe n. sp. and C. chubutensis parasites of Ph. brasilianus and Ph. atriceps, respectively, appears to support a host-parasite association between the C. rudolphii A, B, and C, C. septentrionale, C. chubutensis, and C. australe n. sp. and different species of cormorants belonging to Phalacrocorax.

Infection by Contracaecum rudolphii (Nematoda: Anisakidae) in the Neotropic cormorant Phalacrocorax brasilianus, and fishes from the estuary of the Valdivia river, Chile

Seasonal parameters of infection by the nematode Contracaecum rudolphii in the Neotropic cormorant Phalacrocorax brasilianus (Phalacrocoracidae) and their relation with feeding and infection in fishes from River Valdivia, Chile, were determined. The prevalences of infection in birds were similar during seasons, whereas mean intensity and percentages of adult gravid females were higher in spring and summer, respectively. For fishes no seasonal differences were found in infection. Cormorant diet varied seasonally in relation to fish prey consumed and this can be related to seasonal differences in infection parameters of birds. The high infection in birds should be considered as a potential risk for salmoniculture.