WhaleSwim Adventures offers an eight-night expedition to the South Pacific nation of Tonga, where travelers can frolic with humpback whales. The “Paradise Island Deluxe A” vacation includes six days in the water with the whales, along with the chance to snorkel in the local reefs and underwater caves. All meals, including a Tongan feast, and accommodations are included (recommended only for strong swimmers, from $3,444, excluding airfare; whaleswim.com).

For those seeking more of an adrenaline kick, Absolute Adventures—Shark Diver offers chartered trips from San Diego to Isla Guadalupe, Mexico, off the coast of Baja, where divers don wet suits and scuba gear before being lowered in cages to safely observe great whites. The package also includes an onboard videographer, gourmet meals and accommodation on the expedition yacht ($100,000 per week; sharkdivers.com).

Have only a few hours? There are also plenty of day trips that offer intimate glimpses of the local wildlife. On Australia’s one-day “Blue Mountains Wilderness, Wildlife Park” tour, visitors can feed kangaroos and cuddle koalas, as well as check out the Tasmanian devils and various bird species at Featherdale Wildlife Park ($130; sydneywildernesstours.com.au). Travelers to Dubai can bond with dromedaries on a camel trek into the desert (half-day trek from $90; nettoursdubai .com). After visiting up close and personal with the wildlife, you’ll never want to go to the zoo again.