In this study we analyzed the production of fundamental frequency contours by bilingual Brazilian speakers living in Spain. His production in Spanish L2 was compared with that of native Spanish speakers and his production in Portuguese L1 with that of monolingual speakers of Brazilian Portuguese. The analysis is qualitative, based on the visual observation of patterns in temporarily normalized f0 contours. Statements were compared in three modalities, declarative, total interrogative and pronominal interrogative, elicited in two styles of elocution - read separately and inserted into a narrative. In the analysis we observed evidence favorable to the presence of two phenomena that are related to bilingualism: learning, in the form of patterns produced in Spanish L2 similar to those observed in the speech of native Spanish, and linguistic erosion, which is manifested in the appearance of patterns produced by bilinguals in their L1 that are similar to those found in native Spanish. The two phenomena occur gradually and variably among the speakers analyzed. We identify patterns in the production of f0 contours by bilinguals and propose a preliminary classification of variable behaviors in terms of incorporating native Spanish characteristics into L2 production (learning) and the transfer to Portuguese of Spanish intonation characteristics (erosion). In the discussion of the results, we point out a possible relationship between the occurrence of learning and erosion and the experience of speakers with L2, especially the time of residence in Spain and formal study of Spanish and the amount of use of L1. We propose, based on the Speech Learning Model (SLM-r), to understand the differential manifestation of the two processes in the three enunciation modalities studied as a result of the interaction between the different tonal repertoires of Spanish and Brazilian Portuguese.