By Amy Woodyatt and Sara Spary, CNN

(CNN) -- Bindi Irwin, the 22-year-old daughter of the late conservationist and television personality Steve Irwin, has announced she is expecting her first child.

Nearly five months after her wedding to Chandler Powell, Irwin shared the news of her pregnancy on Tuesday, writing on Instagram: "Baby Wildlife Warrior due 2021."

"Chandler and I are proud to announce that we're expecting! It's an honour to share this special moment in our lives with you," she wrote.

"Though I'm still in my first trimester, we really want you to be part of our journey from the beginning of this new life chapter," she added.

Irwin, a passionate conservationist like her late father, married Powell in March in the gardens of Australia Zoo in Queensland. The venue was opened by her grandparents in the 1970s and is still run by the Irwin family.

Her father, known as "the Crocodile Hunter," died in 2006 at the age of 44 when a stingray barb went through his chest during filming for a documentary.

Bindi's mother, Terri, welcomed the news on Twitter, saying she was "over the moon" at the couple's news.

"This is the best day ever! I am over the moon to announce that @BindiIrwin and @chandlerpowell9 are going to have a baby! Words cannot express the love that is filling my heart," she said via social media. "While I wish that Steve was here to share this beautiful moment, I know that he would be so proud," she added.

Powell marked the news with a statement posted to Twitter, saying that becoming a father "is the highlight of my life."

"Bee, you're going to be the most amazing mother," he added.