@kingtank_101
The Domain is closing because it is no longer up to code for disability requirements. It has nothing to do with the animals, it's literally the law. It's because people with wheelchairs and ECV scooters cannot get down the hill, it's genuinely dangerous. This is the same reason why last year they updated the Africa to Americas boardwalk and this year they're doing the same to the Indo to Africa boardwalk. The zoo has a choice here: either fix the hill, which would be supremely expensive, rebuild the monorail, which they have considered but is a drastic solution when something simpler has presented itself, or close the area and eventually move the animals to the largely unused Old Eurasia/Zoomobile drive-thru section, which is what they're going to do. Moving them makes more sense, especially when the majority of day guests and passholders alike are not fond of the Domain for a number of very fair and understandable reasons:
Firstly, it is extremely remote. Most of the zoo "lands" flow into each other seamlessly: Indo to Africa, Africa to Americas, Tundra and Australasia to Eurasia, etc. The Domain is very much off the beaten path unless you take the Zoomobile to get there, which is not something an average day guest has access to without an upcharge.
Secondly, the exhibits are old and extraordinarily uninspired. Comparing the brand new outdoor orangutan exhibit or even Gorilla Rainforest from 20+ years ago to the ancient grizzly bear, moose and bald eagle exhibits is like night and day. Plus there are a lot of abandoned and unused exhibits and features down there that are embarrassing to look at, such as the overgrown raccoon exhibit left behind after they made the move across the street to the old lynx exhibit, or the Weston Pond viewing platform in various states of decay.
Thirdly and most importantly, there's the infamous hill, which speaks for itself. It's so steep that it's uncomfortable to go down, and it can be downright painful to climb back up. Which of course is another problem: it's a one-way. The only way into the Domain is to dive down into the pit, and the only way back is a slow and frustrating trek upwards on an incline that I swear gets steeper every year (or maybe I'm just old). I myself only do the Domain once a year for this specific reason, and according to the Master Plan the majority of guests agree, as the Domain was labelled as the least popular area in the zoo when visitors and staff were polled on the subject. And of course, there's the key problem that the hill makes the Domain inaccessible to disabled guests. I have a disabled member of my family who'd love to go see the grizzlies, but she can't because her body can't make the journey and it'd be dangerous going down there with a wheelchair or scooter, because if the brakes fail or something like that then that could be catastrophic.
Of course the Domain was built with the monorail in mind, but the monorail has not operated in nearly 30 years and there is no movement on any planned replacements. It's time for a change, it's time to put the premier Canadian zoo's Canadian animals in a place of honour rather than awkwardly shoving them into a hole, and it's time to redevelop the zoo so it can be traversed in full by all guests, including those with disabilities.
Judging by your comment you seem to imply you'd rather keep the zoo the same way it's been since the 70s while still adding new species, rather than take the smaller-than-we'd-like budget the zoo has to work with and use it to improve the lives of the animals currently in our care. The current game plan is to do the latter, and it's one I and many others on the Toronto forums wholly support because we love the animals at the zoo and we want to see them live their best lives. Would we like wild dogs and walruses and koalas and an endless list of other species? Sure. But I'd turn down every single new species in a heartbeat if it meant giving the orangutans the home they've always deserved or adding new indoor viewing for the red pandas and Savanna animals to help guests see them year-round or improving the lives of our tigers by extending their exhibits. That's where the zoo is coming from, and I think it might help you understand if you realize it's coming from a place of love and care rather than a place of laziness and an unwillingness to acquire new species. If everything changes then I'm going to miss my childhood zoo for sure, but if losing that means bettering the lives of the animals as well as the guest experience, then I think we all should be for it.
