Dear Colleagues,
The following article has recently been
published:
Bisi TL, Dorneles PR, Lailson-Brito J, Lepoint
G, Azevedo AF, Flach L, Malm O, Das K. (2013) Trophic Relationships and
Habitat Preferences of Delphinids from the Southeastern Brazilian Coast
Determined by Carbon and Nitrogen Stable Isotope Composition. PLoS ONE
8(12): e82205. doi:10.1371/journal.pone.0082205
Abstract:
To investigate the foraging habitats of delphinids in
southeastern Brazil, we analyzed stable carbon (d13C) and nitrogen
(d15N) isotopes in muscle samples of the
following 10 delphinid species: Sotalia guianensis, Stenella
frontalis, Tursiops truncatus, Steno bredanensis, Pseudorca
crassidens, Delphinus sp., Lagenodelphis hosei,
Stenella attenuata, Stenella longirostris
and Grampus griseus. We also
compared the d13C and d15N values among four populations of S.
guianensis. Variation in carbon
isotope results from coast to ocean indicated that there was a significant
decrease in d13C values from estuarine dolphins to oceanic species. S. guianensis from Guanabara
Bay had the highest mean d13C value, while oceanic species
showed significantly lower d13C values.
The highest d15N values were observed for P. crassidens and T.
truncatus, suggesting that
these species occupy the highest trophic position among the delphinids studied
here. The oceanic species S. attenuata, G. griseus and L. hosei had the lowest d15N
values. Stable isotope analysis showed that the three populations of S.
guianensis in coastal bays had
different d13C values, but similar d15N results. Guiana dolphins from Sepetiba
and Ilha Grande bays had different
foraging habitat, with specimens from Ilha Grande showing more negative d13C
values. This study provides further information on the feeding ecology of delphinids occurring in
southeastern Brazil, with evidence of distinctive foraging
habitats and the occupation of different
ecological niches by these species in the study area.
Best regards,
Tatiana.
-------
Dra. Tatiana Lemos
Bisi
Laboratório de Mamíferos Aquáticos e Bioindicadores “Profa. Izabel
Gurgel” (MAQUA)
Faculdade de Oceanografia
Universidade do Estado do Rio
de Janeiro
Rua São Francisco Xavier, 524 sala 4002, bloco E, 4o
andar
Maracanã, Rio de Janeiro - RJ CEP 20.550-013
Tel: +55 21-2334-0065 /
2334-0795
email: tbisi@yahoo.com.br