Q 115

The SRD lists the octopus (small animal, not the giant variety) as having a grapple modifier of +2, but I can't figure out why. As far as I can tell, it should get +1 from it's BAB, +1 from it's Strength modifier, and -4 for being small-sized. It does have Improved Grab, but that ability doesn't seem to grant a bonus to the grapple check, and the creature doesn't appear to have any racial bonus to grapple checks. Is this because of an unlisted bonus I'm not seeing, or is it ignoring the size penalty?