shiro-iruka means "Beluga Whale" in English.

shiro-iruka written with kanji is 白海豚.
These are jouyou kanji 常用漢字, taught in junior high, chuugakkou 中学校.
shiro-iruka written with katakana is シロイルカ.
shiro-iruka written with hiragana is しろいるか.
Romaji shi ro i ru ka
Kanji 海豚
Meaning White Dolphin
School Level 小1 小2,

Orthography Notes

  • 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: Beluga_whale