Turkish heritage speakers in Germany: vocabulary knowledge in German and Turkish

In the present chapter, first, the migration background of Turkish heritage speakers in Germany will be described. Secondly, the available literature on Turkish heritage speakers with a focus on vocabulary will be discussed. Finally, the results of a recent study on heritage speakers will be presented. The present study supports the findings of previous studies which aim to answer the question whether there is a vocabulary gap in bilinguals, such that bilinguals have smaller vocabularies than monolinguals. A deficit or gap is attested for bilinguals in a number of studies when they are compared with monolingual control groups (for a detailed overview see Thordardottir 2011). However, this gap seems to be an artefact of the methodology since bilinguals use their two languages in different domains (Grosjean 1982, 2001, 2015) and almost never develop a vocabulary in both of their languages that is comparable to monolinguals. We therefore need to include both languages in an investigation of a potential bilingual vocabulary gap. However, even when both languages are investigated, a deficit in vocabulary knowledge, especially productive vocabulary is attested in many studies (for a detailed discussion see Daller and Ongun, 2017). Because the literature presents somewhat inconclusive results, in this study, we wanted to test whether or not the productive vocabulary of a bilingual individual group also shows a gap when compared to monolingual controls. The present study is based on picture descriptions of 23 heritage speakers and two control groups for German (n=18) and Turkish (n=30). We take both languages into account to obtain a fine-grained picture of the bilingual proficiency of the heritage speakers in our sample. A vocabulary gap can be identified for Turkish but not for German. When the children’s total conceptual vocabulary (Pearson, Fernández and Oller, 1993) is considered, however, there is no vocabulary gap for this group of bilinguals