She's ready to go! Bo Derek and a team of boaters, experts and tourists from WildAid went diving with manta rays and whale sharks late last month off the coast of Cancun, Mexico.
"It was such a personal, incredible encounter with nature," Derek, 61, told PEOPLE. "I'm just so thrilled I got to be a part of it."
Derek has been on the board of WildAid for more than 15 years, taking trips around the world with the organization to help reduce the demand on wildlife trafficking. But this was her first encounter with whale sharks.
"Seeing them has been on my bucket list since I was a little girl," Derek, who's been Scuba diving since she was 15, shared. "You get out there in the water and the creatures are just feeding, slowly, gracefully moving around gorging on these fish eggs. It reminded me of that scene in the first Jurassic Park when the family is out with the grazing dinosaurs — even though they're these gigantic creatures they just slowly pass by you. It was very beautiful and peaceful."
The actress said she wasn't frightened by the creatures — which according to National Geographic can grow to nearly 33 ft. and 20.6 tons — but you couldn't be "careless" while near them. "I knew they were peaceful, but you worried you might be in the wrong place — if they moved too quickly you might get based by a gigantic tail."
The area in which the group went diving has the largest aggregation of whale sharks on the planet, according to Wild Aid.
"The entire experience was overwhelming, mind-blowing," Derek said.
Of all the images from the trip, this was the one that stunned Derek the most.
"Manta rays do this very graceful barrel roll but usually complete it so their back is to the surface again," Derek explained. "This one went halfway, stopped and started sinking. I followed him down as far as I could … he was just so still, and I wasn't disturbing him. It was just the two of us in this deep, dark water. I was so thrilled when we got up and found out the photographer had captured the moment, he was so excited, too."
While the animals were beautiful, the concept of the trip was equally as poetic to Derek.
"Not many years ago, these same boat captains were fisherman who were killing these animals," she explained. "Here now as we evolve as humans and being more respectful of nature and the animals around us, these same men are taking tourists out to have these peaceful encounters. It's a very hopeful sign we're going to coexist, in some respects."
Issues with human/animal interaction are happening "all over the world," Derek said. "America isn't exempt. There are threats on all animals. That's why this dive was so encouraging — it's a success story."
Dives like these are a program WildAid has been running for 10 years, offering donors chances to experience wildlife up close with expert assistance. "All of this serves as an opportunity to raise awareness for sharks and other endangered species," a rep for WildAid told PEOPLE.
"Everyone who goes out there is well-versed and educated on how to be respectful and not to interfere," Derek said of the dive. "The group was of a like mind. I was around some really great people."
Derek's next trip with WildAid will be to Indonesia, to its largest marine preserve. "It's going to be incredible, another once-in-a-lifetime experience," she said.