Five Sisters Waterfall in Belize. (Shutterstock)

BELIZE CITY, Belize -- During a family vacation through the parks of the Canadian Rockies a few years ago we all laughed at a sign which advised visitors to "Keep your eyes out!" for local wildlife. I was reminded of that physically impossible yet theoretically sound advice as soon as I arrived in Belize.

Nearly 40% of the land and approximately 13% of the marine areas of this tiny country, which rubs elbows with Mexico, Guatemala and a 321-km stretch of the Caribbean, are protected by assorted governmental and private organizations. This means that Belize, roughly the size of Massachusetts, offers crucial habitats for a mind-boggling array of species -- many of them on the top of most wildlife watcher's must-see lists.

With my eyes out (and my fingers crossed) I headed to Belize in search of three of them: Harpy eagles, jaguars and whale sharks.

Take a bald eagle and give it flamboyantly long feathers around its head, which flare out into a regal, fluttery collar whenever the mood strikes. Now make this fancy-dress predator more than metre tall. Give it talons the size of grizzly bear claws. Oh, and render it nearly extinct. Now you've got a harpy eagle.

An American bird conservation charity, the Peregrine Fund, has been captive-breeding harpy eagles and reintroducing them into Belize for years. Some of the birds now live on the banks of the 45-km-long spring-fed Crab-Catcher Lagoon in central northern Belize.

An afternoon motorboat ride from a dock just south of Orange Walk City took me through the meandering arms of the lagoon. The sun was bright, the water was clear and the muscular mangroves and jungle vegetation pushed insistently at the banks as if trying to join their friends on the other side.

The clean water and lush greenery in this area provides the perfect habitats for more than 400 types of bird and I easily spotted exotic species. Up on a thick tree branch perched a black-collared hawk with its distinctive rust and black coloring. Ospreys circled over head while limpkins (which look like herons but actually belong to their own distinct species) tippy-toed through the shallows.

A night safari using a hand-held light similar to the spotters mounted on cop cars yielded tiny impossibly fluffy American pygmy kingfishers who seemed to be playing a game of "if I can't see you, you can't see me" as my boat inched directly under their perches.

While slipping silently through the misty waterways during a dawn canoe trip I nosed into the bank and witnessed a feathered feeding frenzy as five rarely seen Yucatan Jays gorged greedily on swarming army ants in numbers that made the ground undulate, Indiana-Jones-style.

"I take people out here all the time who are dying to see Yucatan Jays and we never see one," said my guide Rubin, handily summing up the perils of looking for a specific creature.

During just four guided excursions into the Crab-Catcher Lagoon system I saw 49 types of birds for the first time in my life -- including those Yucatan jays. But no sign of my coveted harpy eagle, which would have made it an even 50.

The Rio Bravo Conservation and Management Area, which occupies 105,000 hectares in the northernmost section of the country hard up against the Guatemalan border, is the second largest single protected area in Belize and encompasses 4% of the country's land mass. It's estimated that the RBCMA is home to 200 species of trees, 390 species of birds, 70 species of mammals and -- most importantly -- all of the big cats that are native to Central America, including what some consider to be the healthiest population of jaguars in the region.

As I eagerly walked along jungle trails I knew that even in a cat-rich environment like the RBCMA my odds of seeing one were slim. Jaguars are not just shy, they're practically anti-social. If you see one, it's because it wanted you to see it.

One morning I went to an archeological zone in the forest where University of Texas professors and students are cataloging, but not fully excavating, a Mayan city believed to have been settled in 400 BC. Jungle cats are drawn to the tranquil spot, too, and I came across a tantalizingly fresh scratch mark and scent patch on the outskirts of the ancient city. Somehow I resisted the urge to call out, "Here, kitty, kitty!"

Encouraged, I joined a night drive along dirt roads in the RBCMA. Armed with an ultra-bright flashlight I caught a glimpse of furry movement out of the corner of my eye. What I'd hoped was a young jaguar (I would have even settled for a jaguarundi) turned out to be a grey-tailed fox which, incredibly, climbs trees. A bit further down the road a hard-to-spot Yucatan banded gecko, vividly striped and just a few inches long, appeared.

Still, no jaguar. Perhaps to make me feel better, my guide, Vladimir, told me that in more than 10 years of service in the RBCMA he's seen a jaguar just 20 times. A whale shark is neither a whale nor a shark. At up to 18-metres long it's the largest fish in the world. Decades ago fishermen in southern Belize began noticing large numbers of whale sharks during the mullet snapper spawning season, which occurs near the full moons between March and July.

Not realizing that whale sharks are toothless and feed exclusively on plankton and other nutritious particles in the water (like snapper spawn) gulped into their mouths which can approach 1.5 metres across, the fishermen were terrified. Researchers and scuba divers were thrilled.

Given their size, it's astonishing how rarely whale sharks are seen and interested scuba divers will go to unusual lengths to be in the right body of water at the right time. Many of those hopefuls converge on Gladden Spit Marine Preserve off the coast of southern Belize during the spring and early summer full moons when diving companies in Placencia and Hopkins gladly take them 50 km by boat from the mainland to the spit.

Diving in search of whale sharks means hanging out in open deep blue sea with no reef to amuse you or provide a navigational point of reference. It's like being in a monochromatic bottomless well, or deep space. This makes it easy to lose your bearings as your group of divers swims in search of huge schools of mullet snapper. Find the snapper, the theory goes, and you find the whale sharks.

Like all theories, it doesn't always work that way. Three dives yielded plenty of mullet snapper but zero whale sharks. On my fourth and final dive my group, again, found the fish. Then a pod of bottlenose dolphins found us, swimming above, below and around us for the duration of the 55 minute dive. By the way, it's absolutely possible to grin with a scuba diving regulator in your mouth.

I may not have seen a harpy eagle or a jaguar or a whale shark during my time in Belize but I didn't go home empty-handed either. That's the thing about keeping your eyes out. You never know what you might see.

If you go to Belize

STAY AND PLAY

-- Lamanai Outpost Lodge ($170 per person double occupancy including transfers to and from Belize International Airport, all meals, two standard activities per day and all taxes, lamanai.com) sits on the banks of Crab-Catcher Lagoon and offers bird watching trips as part of one of the most diverse and well-crafted activities menus I've ever seen (from cooking with women in a nearby village to tagging crocodiles).

-- La Milpa Field Station is a solar-powered outpost offering 16 new comfortably appointed cabins built out of local hardwoods with thatch roofs and private bathrooms ($208 double occupancy including three simple but delicious meals a day, pfbelize.org/lamilpa_tours.html). Transfers from Belize City or Orange Walk Town are available. Feel good about your stay knowing that proceeds go to the non-profit conservation group Programme for Belize. See pfbelize.org/index.html.

-- Hamanasi Adventure and Dive Resort -- hamanasi.com -- is a Green Globe certified boutique resort with a dive shop. Summer rates are $195-$325 double occupancy in oceanfront rooms or wonderfully secluded jungle suites on stilts. Rates include continental breakfast. Seasonal two-tank whale shark dive trips are $200 per person.

-- Have dinner at Chef Rob's Gourmet Cafe, in the town of Hopkins. The menu changes everyday. Recent dishes include shrimp bisque ($6), lamb stew in dark beer with Island spices ($18) and grilled pork with balsamic reduction sauce ($17). Cap it off with a nip of "30 Days of Torture," rum infused with orange, lime and anise.

-- Hedge your wildlife bets with a visit to the Belize Zoo ($10, belizezoo.org) about 50 km outside of Belize City. This lovingly run and creatively constructed not-for-profit zoo houses rescued or abandoned wild animals. You're guaranteed a jaguar sighting (his name is Junior Buddy and he's uncannily curious) and you'll also see a pair of harpy eagles along with dozens of other native creatures.