Yogi and the gang land on the property of Yogi's old friend, Mr. Cheerful, when Magilla runs out of bananas. A villain named Dr. Bigot plans to experiment on them with his Bigot ray and turn Mr. Cheerful and Yogi into bigots, discriminating against everyone else.
A friendly hobo (who happens to be Yogi's old friend) finds a lamp with a Greedy Genie who grants all his wishes; however, the genie convinces the man to lust for more, and is soon overcome with greed. The Genie later switches his target to Snagglepuss.
Yogi and the gang visit Ranger Smith and put a show for a bus full of orphan children visiting Jellystone Park. Unfortunately, Wally Gator doesn't have any talents and has to be a curtain puller. An entertainer named Hilarious P. Prankster, as a revenge for being refused by Yogi to be in the show, tricks Wally by offering to make him a comedian. As a result, Wally starts playing mean pranks on everybody and starts losing his friends, until they learn Hilarious is behind Wally's new hobby.
The long-nosed Commadore Phineas P. Fibber is picked up by the Ark. He teaches various animals to lie, and soon they start using their fibs on Captain Yogi to get into their way. Lies soon turn against them, however, when a tornado is coming and Yogi won't believe them.
Yogi gets homesick and the animals go back to Jellystone Park where there is a big party planned for him. However, the Gossipy Witch of the West (who works for Ranger Smith with various professions) finds and spreads rumors all over the park, including one that Yogi is engaged to Cindy and planning to leave the gang forever. At the same time, Chief Short (after seeing the ark and animals) is sure that a big flood is coming and investigates by dressing up as a giant chicken.
A messy man named I. M. Sloppy can't stand to see Yogi's crew cleaning up their ship. He uses his book of sloppy spells to turn himself into a nice gentleman named Mr. Neat and tricks the animals into cutting corners in their jobs.
Peter D. Cheater makes Snagglepuss, Quick Draw McGraw, and Wally Gator join his School where he teaches them the "art of cheating." Things get worse when he tricks Yogi into giving him the Ark.
After a storm, Yogi and his gang stop on an island and need to get more supplies. They meet Mr. Waste (he actually introduces himself as "Mr. Plenty") who encourages the animals to stay on his island and use everything as much as possible. The animals are happy thinking they found a paradise, but Atom Ant (who as an ant doesn't believe in wasting things) soon finds what Mr. Plenty is really up to.
The gang is stopping at an old town called McGrawsville when Quick Draw McGraw inherits it from his grandpappy. However, J. Wanton Vandal and his campers stop in the town and start demolishing antiques. It's up to Yogi and the gang to teach the kids the value of antique objects.
On the way to a birthday party for his friend the Sheik of Sharing, Yogi meets the Sheik of Selfishness. He gives Yogi a magic box, which can give Yogi anything he desires, but soon it makes Yogi act selfish.
The gang stops at "Smog City," a city covered in smog by Mr. Smokestack Smog's smog factory where he has convinced everybody that smog is good for them. He encounters Magilla Gorilla, Peter Potamus and Snagglepuss (who are looking for bananas for the ark) and tries to convince them into his way of thinking.
Jellystone Park is going to be declared the "Neatest Park in the West" and the animals help Ranger Smith clean it up. But a villainess named Lotta Litter tricks them into littering where she uses her power to impersonate anybody.
Two trapeze artists named the Envy Brothers use their "envy rings" on all the other circus acts to make them quit since they are jealous of the owner of the circus and want to trick him into signing the circus to them. However, their plan may fail when Yogi and his friends join the circus.
Wally Gator is sad because he is the only one of the animals who doesn't own a surfboard or any other beach gear. However, a pirate named Captain Swashbuckle Swipe decides to teach him the "easy way" (stealing). Yogi enlists the help of Fumbo-Jumbo the Masked Avenger: a goofy Zorro-like elephant to help recover their stuff.
Cindy Bear gets ownership of a dude ranch, and all the animals come to help her get it ready for the guests. But a bad guy named Mr. Hothead (who goes under the name Mr. Coolhead) uses his invention to make all the animals except for Yogi, Cindy, and Boo Boo lose their tempers. Since they can't work together, the boys won't finish their jobs in time and Mr. Hothead will trick Cindy into selling him her ranch. Will they learn to work things out in a calm way without losing their tempers?
Broadcast in 1972 as part of "The ABC Saturday Superstar Movie" series, "Yogi's Ark Lark" was an animated Hanna-Barbera made-for-TV movie intended to raise ecological awareness. It also served as the pilot for the cartoon series "Yogi's Gang." This one-hour feature was later turned into a two-part series finale of "Yogi's Gang" with new intro and concluding sequences created for each episode. To fit the feature into these new time frames, some of its sequences were shortened or edited out. Aside from its environmental message, "Yogi's Ark Lark" marked a milestone in Hanna-Barbera's history: a wide range of the studio’s characters were united in one story for the first time. This set the tone for future series and specials, such as "Laff-a-Lympics" and "Yogi’s First Christmas."
