Manta Ray (CR 1)

Large Animal
Alignment: Always neutral
Initiative: +0; Senses: low-light vision, Listen +7, and Spor +5

AC: 12 (-1 size, +3 natural), touch 9, flat-footed 12
Hit Dice: 4d8 (18 hp)
Fort +4, Ref +4, Will +2
Speed: Swim 30 ft.
Space: 10 ft./5 ft.
Base Attack +3; Grapple +9
Attack: Ram -1 melee*
Full Attack: Ram -1 melee*
Damage: Ram 1d6+1
Special Attacks/Actions: -
Abilities: Str 15, Dex 11, Con 10, Int 1, Wis 12, Cha 2
Special Qualities:
Feats: Alertness; Endurance
Skills: Listen +7, Spor +5, and Swim +10
Advancement: 5-6 HD (Medium-size)
Climate/Terrain: Warm aquatic
Organization: Solitary or school (2-5)
Treasure/Possessions: None

Source: Monster Manual

*If threatened, a manta ray uses its sise and weight to ram opponents. This is treated as a secondary attack.

Skills: A manta ray has a +8 racial bonus on any swim check to perform some special action or to avoid a hazard. It can always choose to take 10 on a swim check, even if distracted or endangered. It can use the run action while swimming, provided it swims in a straight line.