Yamato Kazakiri is a well-braved zoologist who becomes Zyuoh Eagle and later, alternatively, Zyuoh Gorilla the Red Ranger of the Zyuohgers to fight against the Deathgaliens. After inheriting Cetus' will alongside the Whale Change Gun, he becomes the second Zyuoh Whale (ジュウオウホエール Jūō Hoēru).
As a young boy, Yamato ran away from his dad one night only to end up lost and injured. However, he was rescued by Bud who gave him the King's Credential, through which he transferred his Zyuman Power in order to heal him, Ep. 6: Wild Present as a good luck charm.
Meeting the Zyumans
When his good luck charm (which he didn't know was a stolen King's Credential) fell from his hand and rolled through the woods, he discovered a mysterious giant cube (the Link Cube) which has a slot perfect for his charm, he put his charm in it and saw himself unconscious in Zyuland. He opened his eyes and saw humanoid animals (Zyumen), a shark, a lion an elephant and a tiger looking at him. They thought he was the thief of the King's Credential, but when he explained it was given to him by Bud (an eagle Zyuman), they decided to show him Zyuland. When the Zyumen returned to the Link Cube in order to teleport Yamato back to his world, only to see themselves teleported with him to an unusual dimension in the middle of a war. Their sixth sense reacted to the danger, and when they decided to protect Yamato's dimension, four of the six King's Credentials transformed into Zyuoh Changers to transform the Zyumen into the Zyuohgers. Yamato wanted to become a Zyuohger too and asked a fifth King's Credential for Zyuohger powers. The King's Credential allowed him to transform into Zyuoh Eagle and fight with the Zyumen. The five of them defeated the one who attacked Yamato's dimension, Deathgalien's Jagged, but Nalia made him grow giant, their Changers glowed to teach them how to summon the Zyuoh Cubes to fight the newly grown Jagged, and then their changers teached them how to form Zyuoh King, but Tiger and Elephant were out of the formation, to which Tiger responded "First come, first served?". They defeated the Deathgalien and the Zyumen revealed their identities to Yamato, and told him they had no place to live in, so he offered his home, to which Elephant, (now revelated to be named Tusk), refused. Ep. 1: The Exciting Animal Land
Sometime following their formation, the five Zyuohgers fought and defeated the Kuliner Yokai Wanyūdō while the Ninningers and ToQgers joined forces against the Kibaoni Army Corps and the Evil Army Shadow Line. Shuriken Sentai Ninninger vs. ToQger The Movie: Ninjas in Wonderland
When Sela and Leo were captured and forced to fight in the Battle Show organized by Team Cubaru's Amigard, Yamato got the idea to track them down by having Tusk follow their scent with his elephant nose. Catching up with them just in time, Yamato, Tusk and Amu interrupted their fight at the last minute and backed them up in defeating Amigard.
The Two Robos
With Tusk setting off to confront Amu for skipping her chores, Yamato along with Sela and Leo tracked a malicious presence to a beachfront. Expecting a Deathgalien, what they found was, to their surprise, something completely different as the cyborg monster ShiomanekingIcon-crosswiki emerged. Introducing himself as a member of ShockerIcon-crosswiki, Shiomaneking attacked the Zyuohger trio, believing that, as they had the ability to track him, they would make excellent bases to create new cyborgs from. Transforming to face the monster, the Zyuohgers were interrupted by the arrival of Kamen Rider Ghost, Takeru TenkujiIcon-crosswiki, who was pursuing the monster as well. Making a new ally, the Zyuohgers used their combined strength to defeat Shiomaneking alongside the Kamen Rider and, after Naria grew Shiomaneking, formed ZyuohWild 6*2*3 to quickly destroy him. Catching up with Tusk and Amu, the trio saw Amu resist her turning by Cubaru into the Tiger Moeba, allowing Tusk to return her back to normal.
Soon after, Yamato, pursuing another Shocker cyborg, Yamaarashi-RoidIcon-crosswiki, would bump into Takeru again, using this coincidence to pay Takeru back for his help while also meeting his friends AkariIcon-crosswiki and the GoemonIcon-crosswiki-possessed OnariIcon-crosswiki. Using their combined power, Zyuoh Eagle and Ghost soon enough defeated Yamaarashi-Roid and his Shocker CombatmenIcon-crosswiki. After destroying the Yamaarashi-Roid together, Yamato bid farewell to Takeru as he set off to return home. Appearance! The Mysterious Warrior! Continuing their search for the missing King's Credential, Yamato and the others were interrupted by the arrival of Team Azarudo's Yabiker, who was driving people into frenzies with his Mufflerapper horn. Leo was the first to find him, warning the others to cover their ears, only for Sela to fall victim to Yabiker's Pararira Noise due to her sensitive shark hearing. With Yabiker fleeing after Leo discovered an immunity to his power, the Zyuohgers prepared noise-cancelling head-phones to protect against Yabiker. However, Yamato along with Tusk and Amu were sent into a frenzy by Yabiker, who had Nalia provide him with an improved stereo, while Sela was ironically left unaffected due to the extra protection she sported. Yamato, Tusk and Amu were soon freed when Leo overcome Yabiker's Pararira Noise Ver. 2 with his naturally loud voice and, after the Zyuohgers defeated the Player, formed ZyuohWild to get back at him. Though outmatched by Yabiker's Yoroshiku Rod, ZyuohWild was backed-up by Cubes Lion and Shark and after Yamato used Cube Eagle to form ZyuohKing, the two giant robots were able to destroy Yabiker with their combined power. Ep. 8: Savanna's Melody
One night, Yamato noticed that Sela was out late and, on the following morning, found her shedding a tear as she looked upon a memento broach of her family. Confiding in Yamato, Sela revealed to him that it was the day of her parents' anniversary and that she wished to find the King's Credential in time to return to Zyuland and reunite with them and her younger brother. Yamato suggested to Sela that she write a letter to the family, telling her that, if she believed it would get to them, her feelings would reach them. At that moment, they were interrupted by the Deathgalien presence, setting out to be confronted by Team Cubaru's Hanayaida, who paralyzed all five Zyuohgers by using his Nightmare Perfume to trap them in a recurring dream. In this dream, the Zyuohgers were alerted to the appearance of a giant Hanayaida who they quickly destroyed in ZyuohKing before returning home as Sela began to write her letter before the sequence repeated. However, a voice got through to Sela, which she heard as a call for help. Informing the others, Sela felt a sense of a deja vu, followed by Yamato, leading them to realize that they were stuck in a never ending nightmare, with Yamato waking himself up by finding Sela's brooch before waking up the others.
Catching up with Hanayaida in reality, the Zyuohgers found that he was plotting to use the Cannibalulb plant to consume all life on Earth as they were trapped in his nightmare. Negating his hold on the rest of the populace, the Zyuohgers were constricted by the Cannibalbulb's vines but were saved from being devoured by the arrival of Cube Mogura, who Sela realized had called for help having been woken by the plant's roots before breaking free. Engaging Hanayaida, the Zyuohgers soon defeated him and, forming ZyuohWild to face him as a giant, used Cube Mogura's drill to destroy him. Back home, Yamato returned the broach to Sela, telling her that she could still write the letter though the anniversary was nearly over while reassuring the Zyumans that they would return home as they reflected on their seclusion from their families. However, Yamato along with his uncle avoided the question of his own parents. Ep. 9: A Day Does Not End
Starting a search for Bud, Yamato and the others were drawn to Team Cubaru's Hattena while Tusk was forced to work at Genkuro Oiwa's book store to pay off his bill, finding their opponent indestructible due to his regenerating body. The following day, Yamato and the others gave Tusk a helping hand in getting kids to listen to his reading of The Short-Nose Elephant before fighting Hattena again which led to them being robbed of their words by Hattena, thus being rendered mute, as part of Cubaru's plot to destroy Earth culture by disabling communication. Realizing in the process that Hattena's true form and weakpoint was his hat head, they tried to get the point across via charades before Oiwa stepped in and led the answer to Tusk who struck the hat, freeing all the stolen words and restoring communication with the Zyuohgers proceeding to defeat Hattena.
Bangray's grudge against Yamato intensifies as his next plan involves the creation of a Zyuoh Gorilla. This Zyuoh Gorilla captures Yamato as Bangray uses this opportunity to try and steal the Cube Whale from Yamato.
Chou Super Hero Taisen
Catching up with Amu, Yamato and the others fought against the army of ShockerIcon-crosswiki from the Game WorldIcon-crosswiki alongside various fellow Sentai Rangers and Kamen Riders.
Yamato is a novice zoologist, who as a child, helped Bud, a mysterious bird-man, in the forest. As token of gratitude, Bud gave Yamato a mysterious Cube. A caring person, he's the type that struggles with taking on too much. He is very strong willed and once he sets his mind on something, he'll never change it.
His respect for life and love of animals enables him to use the power of the Zyuoh Changers, something which only a Zyuman should be able to do. This love of animals is what enabled him to help Larry overcome his fear of humans. He also bears a great deal of gratitude towards Bud for saving him in the past.
However, Yamato is not without his weaknesses. He treasures the ones that are close to him, trying his best to look out for and protect them as much as he can. As such, he cannot bear to lose the friends that he has made. This trait is exploited by Bangray, who targets Yamato's old friend Daichi and then later the other Zyuohgers.
Yamato also bears somewhat of a grudge towards his father, Kageyuki Kazakiri, as he felt that his father spent too much time on work to focus on their family. This grudge is worsened when Yamato's mother passes away, as Yamato blames his father for not being there to save her in time. However, in the present time, once Yamato learns that he is only alive now because his father had earlier saved the one who would save him later on, he develops an inner conflict within himself as he struggles as to what he should do.