Hints and Tips for the Zoo Tycoon Zoo at The Zoo Enclave

Hamburger stands are generally more efficient than hot dog stands: twice as filling and half as thirst inducing. They are also more profitable than pizza stands.
Sub Shops and Kids' Snack Stands sell both food and drink. You can save space and money by using these (sparingly) in place of multiple food/drink stands.
Paths will only stair up gentle inclines (one elevation), and then they only go straight. Curves only work on flat terrain. Beware of hill-creep (hills that extend past the fence) when building your exhibits, as it will cause existing paths to break and could interrupt traffic around your exhibits.
Restaurants have bathrooms and trashcans, and satisfy hunger and thirst. Save space and money by using these in place of standalone restrooms and food / drink stands. Drastically reduce the number of trashcans in your zoo, and thereby cut down on maintenance overhead.
The Swim Shack serves many more guests than the Swim with Dolphins attraction. Go with the former if you have to choose one.
Conserve space! Place a Swim attraction on the same plot of water terrain as a boat ride.
Use Fancy Family Restrooms exclusively as soon as they become available, and plan space for their eventual use in your early zoo construction. Unlike other restrooms, Fancy Family Restrooms actually increase guest happiness.

Build wide paths - at least two tiles wide for medium traffic, and three tiles wide for high traffic areas. Low traffic can be done on one tile wide.
Set buildings, especially restrooms and food, drink and gift stands, one tile back from the main path, and build a spur to the stands. Stands set right next to the path restrict traffic flow as guests wait their turns to make purchases.
Stick with one style of layout (grid, leaf, radial, etc). Changing the style mid-zoo confuses guests and can make them angry.
Make redundant paths: always offer multiple routes to every section of your zoo.
Use the cobblestone, brick, gold or boardwalk paths. These have higher aesthetic values and increase happiness.
Place water attractions (Swim Shack, Swim with Dolphins, Boat Ride) near food, drink and rest areas.

Don't build a path leading to your Compost Facility. Staff don't need it, and guests lose happiness when walking past.
Don't use the photo booth. It competes with your gift shop/stand unnecessarily as the photos count as souvenirs. If a guest has a photo, he won't buy a gift and vice versa. Gifts cost more, so encourage that.
Don't place buildings or objects directly on the main path. Items placed on top of path (including trashcans, benches, foliage, etc) block that tile, restricting traffic flow and upsetting guests.
Don't think more = better with trashcans. They actually lower guest happiness. If your zoo generates trash, then of course you'll have to use a few, but try to restrict their placement to a few strategic locations throughout the park.

Animals that can use low fences are: African Buffalo, African Warthog, American Bison, Black Rhino, California Sea Lion, Dromedary Camel, Emperor Penguin, Flamingo, Giant Anteater, Hippo, and Saltwater Crocodile.
You can use low fencing with other animals, provided you build their exhibits using the pit method.
Use the strongest fencing available whenever you can afford it. Longer lasting fences mean slower deterioration and less maintenance overhead.
For lower cost fencing, you can periodically "refresh" your fences. Simply place new fence over existing fence (the new fence will turn orange if you have it placed correctly; incorrect placement shows green) and the new structure is done. Use this technique if you want to cut down on maintenance overhead.

If you're running low on cash and need to refresh an exhibit, use the gate tool. Click on the gate tool in the construction menu and move it to the rotten section of fence. The rotten section will mend once the new gate is in place. Then move the gate back to the original location or to another section. This fixes your fence for free!
Zoo walls don't deteriorate. You can use them as free, no maintenance fencing for your outlying exhibits.
Maintenance workers do not generally repair shared internal exhibit fences without prodding. These are fences shared by two or more exhibits without direct access from outside the enclosures. Workers have to enter the exhibit to repair the fence, and they're not very responsible about it. If you opt for shared fencing, you will need to periodically pick up maintenance workers and drop them in front of sections needing repair. They will fix interior fencing at that point.

Fence values are as follows:

Whatever else you do or don't research, do complete the Staff Training research items. Employees are much more efficient with a little training.
Staff are paid for the month as soon as they are hired, and pay isn't prorated. If you hire an employee on March 30, you will pay them their salary for the entire month of March, and then pay them again on April 1, so always try to hire any staff at the beginning of a month to get your money's worth.
Staff are also paid for the entire month, regardless of when you fire them. If you're going to fire an employee, do it at the end of the month.
Depending on exhibit size, zookeepers can only handle up to 3 exhibits satisfactorily, and may not be able to handle even a single exhibit on their own if it's very large. Be sure to hire enough keepers to keep up with your exhibits!
Zookeepers with assignments work more efficiently than those without. Assign most of your keepers (roughly 80-90%) to specific exhibits, and then hire additional keepers without assignments to roam where necessary.
Zookeepers cannot swim. Remember this when building watery exhibits and be sure there is a land path to all shelters and/or islands. Otherwise, you'll end up with pockets of poo that can't be cleaned and very unhappy animals.
If you're using the pit method, be aware that zookeepers can climb up or jump down one elevation, but no more than that. Exhibits sunk one tile into the ground will be fine, but those sunk (or raised) two levels or more will need step-down elevations for zookeeper access.
Staff don't move quickly. In fact, they're usually a bit slow.

If assigning zookeepers to multiple exhibits, use only exhibits that are near each other (maybe just across the path), and place gates in close proximity for quicker access.
If you have a broken fence, animals can and will escape. Pick up a "monitoring" maintenance worker and place him in front of the fence section to get it repaired immediately. Or use the gate tool trick in the fencing section.

Maintenance workers cannot fix fencing they can't reach. Check your exhibits for any blockages and remove them. You can also pick up maintenance workers and place them directly in front of the sections in need of repair and- provided they've been assigned to fix fences on their task list - they'll start repairing.
Maintenance workers do not repair shared internal exhibit fences without prodding. These are fences shared by two or more exhibits without direct access from outside the enclosures. Workers have to enter the exhibit to repair the fence, and they're not very responsible about it. If you opt for shared fencing, you will need to periodically pick up maintenance workers and drop them in front of sections needing repair. They will fix interior fencing at that point.
Tour Guides are great for guest happiness, but you don't need to overload. 1 Guide for every 300 guests works just fine. By all means, add more if you've the money, but if funds are tight this ratio will suffice.
Overstaffing is just as bad as understaffing, especially if you don't assign staff to specific tasks. Everyone assumes someone else is taking care of everything, and most staff just end up wandering aimlessly about the park mouthing about "monitoring the zoo." Fiddle with staffing levels every so often to find and maintain the balance between the two.

Component	Percentage	Criteria
Animal Happiness	25%	25 points available. Scaled rating of: (Animal Happiness)/(Number of Animals)
Guest Happiness	25%	25 points available. Scaled rating of: (Total Guest Happiness)/(Number of Guests)
Animal Health	15%	15 points available. 100% healthiness earns total; 50% healthiness earns 7.5, etc
Species Diversity	10%	10 points available. Total award based on percentage of 44 available species represented in your zoo
Zoo Beauty	10%	10 points available. Overall zoo aesthetic calculation is unavailable
Zoo Value	10%	10 points available. Scaled rating of: (Cash on Hand)+(Sale Price of Total Zoo)/300
Zoo Research	5%	5 points available. Total award based on percentage of research

Earn the Zoo of the Year award and unlock the Elephant Seal Statue. (MM)
Earn the Excellence in Arctic Exhibit Construction and unlock the Iceberg. (MM)
Earn the Best Sea Lion Show and unlock the California Sea Lion Statue (MM)
Earn the Best Orca Show and unlock the Orca Statue (MM)
Earn the Best Dolphin Show and unlock the Bottlenose Dolphin Statue (MM)
Earn the Arctic Aquatic Care award and a benefactor will donate a pair of Emperor Penguins. (MM)
Earn the Best Zoo in the World award and a benefactor will donate a baby Giant Panda. (MM)

Successfully complete the pre-designed game scenarios to earn rewards for future zoos.

Win the Aquatic Show Park scenario and unlock the Show Grandstand 2 (MM)
Win the Shark World scenario and unlock the Photo Booth.
Win the Super Zoo scenario and unlock the Trio Statue.