kobito-iruka means "Tucuxi" in English.

kobito-iruka written with kanji is 小人海豚.
These are jouyou kanji 常用漢字, taught in junior high, chuugakkou 中学校.
kobito-iruka written with katakana is コビトイルカ.
kobito-iruka written with hiragana is こびといるか.
Romaji ko bi to i ru ka
Kanji 海豚
Meaning Small Person Dolphin
School Level 小1 小1 小2,

Orthography Notes

  • hito ひと becomes bito びと in this word because of a change in pronunciation called rendaku.
  • iruka is a jukujikun 熟字訓 reading for 海豚 in this word. That is: those kanji are only read that way when they come together like that.

Further Reading

Wikipedia: コビトイルカ