Why is Japari Park pretty much rundown and abandoned?... Even the creators of the FRANCHISE didn't have enough money left to keep Japari Park running!
In Episode 3, it almost makes sense that Crested Ibis mistook Lucky's knowledge quips for Kaban-chan praising/insulting her, after all: Lucky and Kaban-chan are voiced by the same voice actress, Mirai's...
Why is Tsuchinoko so secretive and prone to hiding? Her original species is a cryptid.
The series' CGI isn't of the highest quality for sure, but the way Professor and Assistant hold their spoons in episode 7 looks particularly awkward... until you realize it's similar to how birds pick things up with their talons.
The reason the owls asked Kaban to cook for them is because they are tired of eating Japari buns. Considering that they apparently demand large quantities of Japari buns for helping other Friends (remember how Beaver needed to pay three months' worth of Japari buns to them?), it's no wonder that they are the only Friends in the entire show who don't want to eat Japari buns anymore.
How could Gray Wolf write manga if almost none of the Friends know how to read? In the final episode, it's revealed that her manga have no dialogue and she does the narration, similar to a kamishibaiya.
Why at the end of episode 11 are the PPP group missing, instead with a barely concealed Lucky Beast making a weird sound? Because that's the sound Lucky Beast makes when he communicates through other Lucky Beasts, as shown when Brown Bear is carrying Lucky Beast away from Kaban, whom Lucky Beast has realized is going back to try and save Serval. Lucky Beast sought out their help and they went running to the mountain, as shown in the next episode.
Kaban seems to take over the role of the park guide from the mobile game, even having a very similar hat. It's not similar, it's the same hat, having lost one of its feathers and gotten slightly banged up, and Kaban is a Friend version OF the original park guide!
Why was the first human Friend "born" in the Savannah Area? Because humans originally came from Africa!
Friends regenerate from all but the most grievous wounds. This includes their costumes. Kaban's gloves and leggings regenerating during the 1 month timeskip which hints that she may not have "returned to nature" after all.
It is rather logical for Serval and Caracal to be friends. The closest relatives of the Serval have been proved to be the African golden cat and the caracal; for this fact, they're even placed in the same genus.
Why does Crested ibis have Reflectionless Useless Eyes despite her species not being extinct? It's not because her species came very close to going extinct — infamously hitting a worldwide population of 7 at it's low point. It's because the Crested ibis — or rather, the Japanese Crested ibis — did go extinct... in Japan. The last Crested ibis died in Japan in 2003, with the 7 remaining ibises being found in a remote part of China.
When the penguins are rehearsing, they hum together instead of singing. This makes perfect sense when one considers what real penguins sound like.
Tsuchinoko, a cryptid, is an archaeologist.
When Bottlenose Dolphin speaks underwater, her mouth doesn't move. This may seem like faulty animation... until one realizes that cetaceans don't breathe through their mouths (or else they would drown when they eat).
It is more likely the second plane was a P-3 Orion, which is a maritime ISR (Intelligence/Surveillance/Reconnaissance) platform. Under the assumption it was intended to provide a 'Bomb Damage Assessment' but ultimately crashed alongside the B-2, whatever took out the pair is no less fearsome.
The Kanji on the rock on the stone at the top of the volcano (visible in the bomber picture above) are "五合目" which is a reference to a famous station close to the top of Mount Fuji. If the volcano is Mt. Fuji post-eruption, that means Japan — er, Japari park is Japan after a rather epic geological event.
The geography of Season 1 Japari park is compatible with the East Fuji area, although its later revealed to be on an island that resembles Kyushu more. Japari Park is also said to be located in Okinawa.