ɐkˈoːɹdɪŋ tə sˌʌm ˈɔːθɚz, ɪɾ ɐpˈɪɹz təbi ðə kˈeɪs ðætðə spɹˈɛdɪŋ ʌv ðɪs spˈiːsiːz aʊtsˈaɪd ɪts nˈætʃɚɹəl ɹˈeɪndʒ hˈæzbiːn mˌeɪd pˈɑːsᵻbəl baɪ ðə plæŋktˈɑːnɪk lˈɑːɹvəl stˈeɪdʒ bˌiːɪŋ tɹænspˈoːɹɾᵻd ɐlˈɔŋ wɪð bˈæləst wˈɔːɾɚɹ ɪnðə hˈʌlz ʌv ʃˈɪps, ɔːɹ ðæt ˈɛɡ mˈæsᵻz mˌeɪhɐv bˌɪn tɹænspˈoːɹɾᵻd wɪð pɹˈɑːdʌkts ʌv mɚɹˈiːn fˈɑːɹmɪŋ.
According to some authors, it appears to be the case that the spreading of this species outside its natural range has been made possible by the planktonic larval stage being transported along with ballast water in the hulls of ships, or that egg masses may have been transported with  products of marine farming.