Birdo

"Clearly this is a test for me. Yes, the powers-that-be want me to go out on my own. Once I overcome many hardships, I shall be one step closer to superstardom!"

- Birdo

Birdo, self-nicknamed Birdetta and Birdie, is a recurring character in the Mario series. In fact, there have been multiple characters known as "Birdo," similar to the multiple Yoshis that have appeared throughout history. The concept of a Birdo character was not solidified until the same pink Birdo began appearing in various spin-off titles. The central Birdo character (that appears in the Mario Kart series, the Mario Party series, and the various sports titles) wears a red bow and a diamond ring. She also has some sort of relationship with Yoshi, as they are default partners in various competitions.

Super Mario Bros. 2
The first appearance of Birdo is in Super Mario Bros. 2, where she appears as a boss character in many levels, serving the evil villain Wart as he enslaves all of the creatures of Subcon. In her standard pink form, Birdo spits eggs; in her red form, she also spits fireballs, and in her grey form (green in the remakes), she only shoots fireballs. The standard pink version appears as an enemy in World 4-3, the green one serves as the boss in World 6-1 and 6-2, the red type appears before boss battles, one in World 5-3 before Clawgrip's fight, another in World 6-3 before Tryclyde's fight, and two in Wart's castle, one of which spits out the key once it is defeated.

The credits of Super Mario Bros. 2 mistakenly label Birdo as Ostro, and vice versa, a different enemy that has nothing to do with Birdo. However, this is fixed in Super Mario Advance. To defeat Birdo in Super Mario Bros. 2, the player has to jump on her eggs and throw them back at her. However, if Birdo is green, the player is required to throw Mushroom Blocks instead. Most Birdos hold Crystal Balls, but one Birdo in World 7-2 holds a key, which is needed to get to the Mask Gate leading to Wart.

Super Mario Advance
In Super Mario Advance, a remake of Super Mario Bros. 2, there is also a robotic Birdo boss named Robirdo, who takes over Mouser's position as the boss of World 3. Super Mario Advance is also notable for being one of the last games to give Birdo understandable voice acting, as further games would simply allow her to emit honking noises. In this game, Birdo spoke clear sentences such as, "This is as far as you go!" and "Well, hello there!". She is portrayed by Jen Taylor.

BS Super Mario USA
In the Satellaview special BS Super Mario USA, Birdo first received a speaking role, though it is mostly lost due to the broadcast nature. Taking place sometime after Super Mario Bros. 2, Birdo and the variant friends again serve Wart and invade Subcon. Birdo is fought in the same way as in the predecessor, though this time Birdo may appear randomly and invincibly fly at the player. She can also throw multiple eggs in the air and sometimes can throw bigger ones. Like Wart and Mouser, Birdo appears frequently as a card on the screen and can cast spells to switch the player character or change enemies into bombs. In the end, Birdo and her companions lose again against Mario and friends, although it is said that they would receive better treatment in the future. The voice actors for the three Birdos are all okama, a Japanese term for men who act and dress like females. This only furthers the franchise-long running joke about Birdo's ambiguous gender.

Wario's Woods
Birdo makes her first reappearance in the Mario series since Super Mario Bros. 2 in Wario's Woods, a puzzle game released for both the NES and the SNES. Birdo serves as a primary heroine in the game as she assists Toad and Wanda throughout the game. Throughout the game, the trio go up against Wario as he sends out the brainwashed monsters of Wario's Woods to attack the Mushroom Kingdom.

Although Birdo is not playable (as she appears only in the top right corner of the screen), she aids Toad (the main hero) by providing him with encouragement and as a look out for Wario throughout the rounds. Birdo will also shout instructions and encouragement to Toad from the corner. If Toad takes too long to complete a level, Wario would grab Birdo, replace her, and cause trouble for Toad. After Wario’s timer is up, Birdo returns, and continues to help Toad. The round ends once Toad defeats all the enemies. The instruction manual for this game calls Birdo "Catherine", which is her original Japanese name.

Super Mario RPG: Legend of the Seven Stars
Birdo appears as a boss in Super Mario RPG: Legend of the Seven Stars. Birdo is first seen as an egg named Shelly who is found in Nimbus Castle (while the stronghold was under the control of the usurper queen Valentina). The egg is cared for by a Shy Away, who intended to use the newborn Birdo as a weapon. When the Shy Away sees Mario, he quickly abandons his post and flees, leaving Shelly exposed. Mario could then speak to the Birdo inside Shelly, who would request for Mario to play with her. If Mario complies, a battle between his party and Shelly would begin.

Although Shelly never attacks or performs any malicious moves toward Mario and friends, the group could gradually split the egg open to reveal Birdo. She then would introduce herself and start attacking. After suffering more attacks from Mario and company, Birdo would also raise her attacking methods, beginning to shoot out the explosive Eggberts rather than normal eggs.

Depending on a turn, in which Birdo shoots out, Eggberts would actually fling the explosive eggs back into Birdo's nest, where they could be attacked so that they would explode and deal massive damage to Birdo herself. Despite the pain and anger she shows ambiguous signs of going through, Birdo eventually gives up mid-battle due to the fact that she found Mario and his friends too cute to destroy. After being defeated, she gives the key to Mario. Birdo remains within Shelly and Mario gets to the back door of Nimbus Castle.

Mario Tennis (Nintendo 64)
Birdo eventually appears in Mario Tennis for the Nintendo 64, making her sports game debut. She appears next to Yoshi, and the two are seen to be very affectionate. In this game, Birdo competes as a speed player, and is one of the new girls. In the intro of Mario Tennis, Birdo is seen entering the court after Paratroopa, and she faces off against Princess Peach in the tournament. Later, she is seen with Paratroopa and Yoshi, when Bowser interrupts the fun. Her own court can be unlocked when the player wins the Star Cup with Birdo in doubles. Also, when the player chooses Daisy in the double tournament mode, Birdo would be her default partner. This is the first game to ever give Birdo understandable voice acting. She is portrayed by Jessica Chisum.

Mario Tennis: Power Tour
Birdo appears as a non-playable character in Mario Tennis: Power Tour for the Game Boy Advance. She is seen in the background of the game when Ace and Clay get off the plane to get to the Peach Dome tennis court.

Mario Tennis Open
Though Birdo herself does not physically appear in Mario Tennis Open, one can unlock a suit of her for customizing their Mii with. It can be unlocked by winning a match against an Ace computer in Exhibition mode. Her racket is also purchasable for use by Miis.

Mario Golf: Toadstool Tour
Birdo appears as a playable character in the game Mario Golf: Toadstool Tour. In this game, she appears from the start. Her medium size makes her a balanced character. When playing as Birdo and getting a nice shot, her swing consists of a rainbow. This is actually very similar to the Yoshi golf swing. This game is the first game in which Birdo uses a rainbow ability. This is also the first game to feature Kazumi Totaka, Birdo's current voice actor.

Mario Golf: World Tour
Birdo appears as an unlockable playable character in Mario Golf: World Tour. She is unlocked after 55 Star Coins are collected in Challenge Mode.

Super Smash Bros. Melee
In Super Smash Bros. Melee, Birdo reappears as her two-dimensional Super Mario All-Stars sprite on the Super Mario Bros. 2-based stage. Sometimes, Birdo comes out from the side of the stage and shoot eggs, hurting any player who comes in contact with them. Like in Super Mario Bros. 2, these eggs could be jumped upon and picked up by the playable characters. Birdo can easily be destroyed by a strong attack, however. She also appears as one of the two trophies that must be collected in order to unlock the Mushroom Kingdom II stage (the other trophy is a Pidgit).

Super Smash Bros. Brawl
In Super Smash Bros. Brawl, one of the names that can appear whenever players press the random button when they're naming their custom stage is "BIRDO". Also, a pink Birdo appears as a trophy. Unlike in Super Smash Bros. Melee, however, this trophy is not two-dimensional. It can be unlocked when the player clears All-Star on Hard difficulty.

Super Smash Bros. for Nintendo 3DS / Wii U
While Birdo does not appear in the 3DS version, she does make an appearance in the Wii U version as a trophy. It depicts her winking and standing near a Birdo Egg. The trophy also features information about her appearances in Super Mario Bros. 2 and Doki Doki Panic.

Despite having appeared in many other games, Super Mario Bros. 2 is the only title listed in Birdo's game appearances. Other characters usually have two titles listed.

Mario Kart: Double Dash!!
Birdo's first appearance in the Mario Kart series is in Mario Kart: Double Dash!! as Yoshi's default partner. After the player unlocks the second wallpaper, Birdo is teamed up with Peach. Birdo's special item is the Birdo Egg, which differs from Yoshi's attack in that it has pink spots instead of green. The egg is also different from Birdo's original pure white eggs. Birdo's unlockable kart is called the Turbo Birdo, which features average speed and acceleration, while also having above average weight. Her emblem appears throughout the Dry Dry Desert course, and the staff ghost uses Birdo and Yoshi in the Turbo Yoshi. Yoshi and Birdo are also the staff ghost of Yoshi Circuit, using the Turbo Yoshi kart.

On Mushroom City and Yoshi Circuit, there are signs posted that read "Ribbon". In much smaller letters in the center, it reads "Birdo watching", a pun of birdwatching. They feature a picture of Birdo posing. Yoshi Circuit and the posters reappear in Mario Kart DS, and are Birdo's only appearance in the game.

Mario Kart Arcade GP 2
Birdo is not playable in Mario Kart Arcade GP 2, but she makes a cameo in signs and in the crowd when the player receives a trophy.

Mario Kart Wii
Birdo later appears in Mario Kart Wii as a middleweight, unlockable character. Birdo has an equal balance of weight, top speed, and acceleration. However when she goes off-road, she loses a moderate amount of speed. She is unlocked when the player defeats 250 other players in online racing, or when the player does Time Trials on 16 different courses. Birdo shares the medium-sized group of karts and bikes, but all in her own favorite colors. Birdo's egg emblem appears throughout the Dry Dry Ruins course, similar to how it appears in Mario Kart: Double Dash!!s Dry Dry Desert. Birdo receives a small weight and off-road boost, while her best bonus is the mini-turbo stat. Birdo's mini-turbo is tied with Diddy Kong's, while being inferior to that of Koopa Troopa, Dry Bones, Wario, and Dry Bowser. Birdo is the only playable female character to not receive a speed bonus. Birdo is also the only playable character, besides Miis, that isn't used as a staff ghost.

Mario Kart 8
Despite Birdo herself not physically appearing in Mario Kart 8, a picture of her along with Peach and Daisy appears on some of the "Women of Racing Organization" ads seen on N64 Royal Raceway.

Mario & Luigi: Superstar Saga
In Mario & Luigi: Superstar Saga, Birdo helps the heroes by disguising herself as Princess Peach when Cackletta and Fawful visit the Mushroom Kingdom. When Cackletta attempts to steal the princess's voice, she gets Birdo's instead. Then, when the Beanish witch tried to use the "pure" voice to awaken the Beanstar, it went berserk. All of this is not revealed until later in the game, when Toadsworth and Peach explained the situation to the Mario Bros. As they spoke, Birdo appears and starts wildly chasing two of Lady Lima's assistants, after winking at them flirtatiously.

Sometime later, Birdo replaces Bowser as Popple's "Rookie" out of her mad love for the Beanish crook. Oddly, she is now an enemy of the Mario Bros., even though she had been a helper before in the game. Birdo is a powerful opponent, as one of her attacks involves sucking in Mario or Luigi into her snout. If Birdo is successful in this, it will not only hurt the unfortunate Mario Bro. she sucked up, but will also restore her own HP. The only way to dodge this attack is to hit Birdo with a hammer as her target is drawn near. She can also spit out flaming eggs in a wild, sporadic way. Mario and Luigi must time their jumps to avoid the eggs and the resulting flame each of them creates after their impact. Birdo can also inhale Popple to place him inside one of four protective but deadly egg shields. One egg holds Popple; the other three each contain Designbomb-like enemies that will rush forward after their egg is broken open and need to be jumped over. The main difference between Birdo's and Popple's first Rookie's attack patterns, however, is that Birdo won't counterattack the Mario Bros. if they attack Popple first, making them both easier to defeat. Birdo, however, becomes stronger after Popple has been beaten, as she turns red and says "You may have defeated my darling, but that's as far as you go!" In this state, her attack power is much higher and she now targets both bros. with her egg attack instead of just one and does it much faster.

After Popple and Birdo fail in their attempt to destroy the Mario brothers, Popple blames it all on Birdo and even goes as far as to fire his latest apprentice. Birdo responds by furiously knocking him away through a wall and ending their relationship. She then gives a short speech about her new dedication to strive towards super-stardom, expresses her anger at Mario and Luigi, and runs away. Although Cackletta stole Birdo's voice, she is still able to speak when Mario and Luigi battle her and Popple. This appears to be an error in the game, but Birdo may have gotten her voice back after Cackletta used it on the Beanstar.

Mario Superstar Baseball
In Mario Superstar Baseball, Birdo makes her first appearance on the baseball field. She is a balanced character, who has a slightly above average batting stat, but is lacking in all other areas. Her special pitch/hit is the Weird Ball, when the player purchases the Weird Ball in the store from the Challenge Mode, Birdo is able to use her special move. She is found on Yoshi's team as a unlockable sub-captain, and could also be chosen as a captain in Exhibition Mode. Her alternate names are: Birdo Models, Birdo Beauties and Birdo Bows. Birdo shares good chemistry with Yoshi, Shy Guy, and Petey Piranha. Also she doesn't share a bad chemistry with the rest of the characters.

Mario Super Sluggers
In the sequel, Mario Super Sluggers, Birdo takes up her role as a team captain, but still does not have her own stadium. Compared to the predecessor, Birdo gets a good boost in her batting and fielding skills, along with a small speed increase, while still being a weak pitcher. Her Star moves include the Cannon Swing and Suction Ball. Birdo has good chemistry with Daisy, Yoshi, Petey Piranha, Shy Guy, and oddly enough, Toadette, and bad chemistry with Tiny Kong, Princess Peach, Baby Peach, and a Blooper. Birdo also appears in the Challenge Mode, where she is stuck in a nearby tree, and the rainbow bridge that leads to her is currently down, so the player will have to tackle Bowser Jr. to restore it. He'll challenge the player to a minigame of "Hit Piranha Plants." After Bowser Jr. is defeated, the player can climb the rainbow bridge and speak with Birdo to add her to the team.

Mario Party series
In Mario Party 7, Birdo is a secret guest of Toadsworth, who resides on the Duty Free Shop. She is one of the two new characters, the other being Dry Bones. They join up to go on a luxury cruise around the world. This is the first game in the Mario Party series with Birdo as a playable character. She is unlocked with 1,000 mileage points on the Duty Free Shop. In this Mario Party installment, Birdo's emblem is her red bow, and her default partner is Yoshi in the "Team Mode" (their team orb being the Egg Orb).

More recently, MC Ballyhoo and Big Top invited Birdo and her friends to the Star Carnival during the events of Mario Party 8. In this game she appears as a playable character from the start and her automatic partner is Yoshi. Their team name is "Egg Explosion". When Birdo emerges victorious from the Star Battle, she is crowned the Superstar and wins a year's worth of candy. This applies to the other characters, too.

She also appears in the Japan-exclusive arcade game, Mario Party Fushigi no Korokoro Catcher, as a playable character.

She returns as a playable character in Mario Party 9.

Birdo appears in Mario Party: Island Tour as a non-playable character. Here she is a judge in the minigame The Choicest Voice.

Mario Hoops 3-on-3
Birdo is an unlockable character in Mario Hoops 3-on-3, playing alongside characters from the Final Fantasy series. She is unlocked when the player finishes the Hard Mushroom Cup with a bronze rank. Here she is an all-around type and her Special Shot is the Egg Shot. She begins by spinning around twice. Later, Birdo catches the ball in her snout, jumps, and spits it out toward the basket as an Egg. To perform this move, the player must tap out an upside-down triangle twice. Once again, Birdo still does not have her own stadium, but she appears along with Yoshi in one of the screens of the Mario Stadium.

Itadaki Street DS
She is also playable in the Japanese game Itadaki Street DS, a crossover with Dragon-Quest. To unlock Birdo, the player needs to defeat her in Luigi's Stage Level 1. Birdo's head and clothings are collectibles that can be equipped on customizable characters.

Mario & Sonic at the Olympic Games
Birdo, along with Donkey Kong and many others, were originally going to appear as playable characters in Mario & Sonic at the Olympic Games, but were scrapped from the final product for unknown reasons.

Mario & Sonic at the Olympic Winter Games
Although Birdo is not a playable character in the Wii version of Mario & Sonic at the Olympic Winter Games, she appears as a VIP member: a character who watches the player in certain events, and if found, awards them with 100 points. It's possible for the player's Mii to wear a Birdo costume, once Birdo is found in an event her character suit is available in the shop for 100 points. She also has a sticker available for use on the player's equipment. In the Adventure Tours mode on the DS version she is seen in Cubyrinth. Yoshi loses his skidding table but luckily Birdo has found the item. When the player goes to her she says she has found a skidding table. Yoshi tells her that the table belongs to him, but she says otherwise. Birdo claims that the skidding table is for an elite athlete, so Yoshi must prove himself before she can give him the item. She challenges him to a Ski Cross Race. Once defeated, she gives up the skidding table and stays in Cubyrinth, available for rematches.

Mario & Sonic at the London 2012 Olympic Games
Birdo appears as one of the rivals to defeat in the Wii version of Mario & Sonic at the London 2012 Olympic Games. She is found in the London Party mode and must be faced in the 100m Freestyle event, and later in Badminton with a blue Birdo. Despite Birdo being a recurrent character in many games, this is the first one to give her a theme.

Mario & Sonic at the Sochi 2014 Olympic Winter Games
Birdo appears in Mario & Sonic at the Sochi 2014 Olympic Winter Games as a rival in the Legends Showdown mode. Birdo is found in Area 1, and faces off against the player, alongside three other Birdos, in Ice Hockey.

Captain Rainbow
In the game Captain Rainbow, Birdo is a damsel-in-distress. She lives on Mimin Island, in the so-called Kawaii Ouchi, or Cute Home. It is located on a remote place of the island. The Cute Home represents Birdo's personality and her likings: the interior consists of mostly pink and red equipment decorated with many heart and ribbon emblems.

In the game, Birdo is imprisoned for using the female bathroom, as the robot jailer does not believe her when she insists she is a girl. She gets quite upset about this, and asks Nick to go to her Cute Home and find something that will prove she is not lying. Nick finds a mysterious object under Birdo's pillow (which is blurred out, though it is implied to be a vibrator), it serves its purpose and Birdo is released.

Birdo develops a crush on Nick, and calls him her "boyfriend". Nick accompanies her in her walks near her Cute Home, and she helps him carry a fallen Star to the altar on the top of Mimin Island. If Nick lets Birdo's wish be granted, she flies into the sky with the Star and disappears.

Fortune Street
Birdo returns as a playable character in the Wii follow-up to Itadaki Street DS, Fortune Street. She is available from the start. Her non-playable character rank is a D.

Paper Mario: Sticker Star
"Heart of a woman, heart of a man.... Both feel love's grace...."

- Birdo

Birdo makes her Paper Mario series debut in Paper Mario: Sticker Star. Here, she appears in the level of W4-1: Snow Rise, on a giant swing as Mario comes to a cliff and hits a nearby tree. She will perform to him a short serenade and then give him the Goat statue.

Birdo later shows up at the parade at the end of the game. She is shown in the three-minecart-chain with two Shy Guys for the Bowser's Snow Fort section of the parade.

Kirby series
Birdo makes an appearance as spectator in the minigame: "Megaton Punch" from Kirby Super Star.

Yakuman DS
She is one of the opponents to defeat in the Japanese game Yakuman DS. She can be found on the easy challenges.

Physical description
Birdo is a member of the species of the same name. Like all Birdos, she is a dinosaur with a funnel-shaped snout and a body structure that is similar to a Yoshi, though slightly shorter and with a row of spikes on the tail, not the head.

Birdo is mostly pink, with a rounded white belly, red tail spikes and purple spots on her cheeks. She has purple eyes, each of which is framed by three long, thin eyelashes. She does not have hair, and instead wears a big red bow atop her head, which is usually her emblem. On her left hand is a large diamond ring set in gold, the origins of which are unknown.

Birdo commonly wears purple eye makeup. In her team name, "Birdo Bows", from Mario Super Sluggers, she wears lipstick, which is odd because she doesn't use lipstick during the game, nor in most of her other appearances. In the Japanese commercial for Super Mario All-Stars, she wears a white stole, a very expensive black dress adorned with a black necklace with many pearls, and a very elegant fan. Overall, however, Birdo’s looks have not changed as drastically as many other characters have through the ages.

Personality and traits
Birdo displays great determination and confidence in all aspects of her life. In Mario & Luigi: Superstar Saga, Birdo revealed her goal of becoming a Superstar. Birdo has tackled a wide variety of sports and was the first known Birdo to emerge in the public spotlight in Mario Tennis.

Birdo perceives herself to be very beautiful and feminine. Birdo often strikes eccentric poses to show off her appearance. Also, she is portrayed to be very friendly, and enjoys being with the whole Mario crew. This is shown when losing a round of 18 in Mario Golf: Toadstool Tour, where she never fails to be adorable. She also exudes charm and elegance. Additionally, Birdo always wears a massive diamond ring on her finger. In Mario Party 7 and Mario Party 8, when Birdo gets a Star, she shows off this ring during one of her poses.

Always looking for love, Birdo has had a variety of crushes and relationships throughout her life. Birdo is very flirtatious and affectionate with others, even when she doesn't know them very well, as evidenced in Birdo's relationship with Popple in Mario & Luigi: Superstar Saga. In the same game, Birdo expresses her high opinion of love and romance, explaining her flirtatious nature and drive to find love. The effect of these whirlwind romances on Birdo have only been hinted at in her Egg Shot move in Mario Hoops 3-on-3, which sends broken hearts flying; this is a stark contrast to Princess Peach's Heart Shot.

Powers and abilities
In addition to eggs, Birdo can shoot fireballs from her snout, though this ability is only displayed in Super Mario Bros. 2 and its subsequent remakes. Birdo has also shown the ability to utilize her snout in a manner similar to a vacuum, using it to suck things closer to herself or even swallow them; Birdo displays this ability in both Mario Superstar Baseball and Mario & Luigi: Superstar Saga, the latter of which also has her leeching away the health of those she sucks up. On occasion, Birdo has enveloped people, including herself, in large eggs, in order to increase defense. She is often classified as all-around in sports games, where she has a great deal of strength. She also has shown this strength when angered in Mario & Luigi: Superstar Saga, when, after discovering that Popple did not actually love her, she knocked him right through a wall, indicating she has super-strength.

In Mario Golf: Toadstool Tour, hitting a nice shot while playing as her will cause a rainbow to form similar to Yoshi, but rainbow abilities have since then not been seen. Birdo also has some hints of heart based power similar to Princess Peach as shown in Mario Golf: Toadstool Tour in her victory cut-scene and Mario Hoops 3-on-3 in her special shot. However, they are not as strong or as useful as Peach's hearts. This often has comedic results, such as when they only succeed in charming Birdo's Golf trophy into the air for a short time until it fell down again, to its owner's great surprise.

Gender
According to the North American instruction manual of Super Mario Bros. 2 (pg. 27) : "He thinks he is a girl and he spits eggs from his mouth. He'd rather be called “birdetta.”" This statement applies to all translations of the title. The official guide continues to refer to Birdo as a "he" as well. In Japan, Birdo is portrayed as a male who believes she is a female and prefers to be called by a nickname, "Cathy", rather than her real name "Catherine". As recently as Super Smash Bros. Brawl, Birdo's Trophy description describes the character as "gender indeterminate", and uses the pronoun "it" rather than gender-specific pronouns such as "he" or "she". However, Nintendo of America and Nintendo of Europe usually refer to Birdo as a girl.

The confusion surrounding Birdo's gender has also been addressed in a light-hearted matter, such as when Popple pauses before settling on calling Birdo a "dame" in Mario & Luigi: Superstar Saga, and is also shown in the U.S. manual of Mario Golf: Toadstool Tour, where all the female characters have a pink dot behind them, including Birdo. In Super Mario Advance, though, the Birdos in that game had female voices, but the pitch level of the voices varied, depending on Birdo's color. The pink Birdo had the highest pitched voice, while the green Birdo had the lowest pitched voice in that game; the red Birdo's voice had a pitch level that's in between.

In the game Captain Rainbow, Birdo is heard with a deep, male voice which gets high-pitched when she gets angry or excited. Additionally, in the game's second trailer, Little Mac from Mike Tyson's Punch-Out!! speaks about Birdo, calling her a "young lady," only to take a short break and ponder. His final verdict is "Depending on one's view point, she is a young lady." In the game, Birdo's indeterminate gender also forms the basis for a side quest to find proof that she is a girl (which is found, but censored).

Relationship with Yoshi


She has a special relationship with Yoshi, since they are often partners in sports and party games.

In Mario Kart: Double Dash!!, the two are partners and share a similar Special Item. On the official Japanese site for Mario Kart: Double Dash!!, the description for Catherine states "Catherine appears to be Yoshi's girlfriend... or does that mean boyfriend!?" (「ヨッシーの彼女に見えて実は彼氏!?」)

In Mario Tennis for the Nintendo 64, they share a tennis court and are default partners; the two are seen to be very affectionate. In the Mario Baseball series, they share good chemistry with each other, and she is the Sub-Captain of Yoshi's team. The two also share the same Special Orb in Mario Party 7.

Mario Kart: Double Dash!! information

 * Partner: Yoshi
 * Personal Kart: Turbo Birdo
 * Special Item: Birdo Egg
 * Bio: "Birdo decked out in her favorite bow and ready to race!"
 * Bio 2: "You might be asking yourself who Birdo is. Of course, you'll be pondering this on the side of the road after Birdo's giant egg has crushed your kart."

Super Mario Advance information

 * Bio: " Watch out for Birdo's special egg attack. The best way to deal with Birdo is to catch the eggs and toss her right back. "

Mario Golf: Toadstool Tour information

 * Bio Quote: "I love to golf and now I want to play other golfers! Are you in?"
 * Range Marker: 209y.

Trivia

 * In Super Paper Mario, there is a Sammer Guy named Squatting Birdo, an obvious reference to Birdo and her species. Also, like a few other Sammer Guys, Squatting Birdo recognizes his namesake as an almost deity-like creature, and his ramblings when first encountered suggest that Birdos are flightless birds rather than dinosaurs. This may have been a reference to the confusion between Birdo and the ostrich-like Ostro in Super Mario Bros. 2. Birdos did indeed fly in The Super Mario Bros. Super Show!, however.