has the information online, or the Monster Manual page 315 has it as well.
To quote the Monster Manual:
Spell-Like: Spell-like abilities are magical and work just like
spells (though they are not spells and so have no verbal, somatic
material, focus, or XP components). They go away in an antimagic
field and are subject to spell resistance if the spell the ability resembles
or duplicates would be subject to spell resistance.
A spell-like ability usually has a limit on how often it can be
used. A spell-like ability that can be used at will has no use limit.
Using a spell-like ability is a standard action unless noted otherwise,
and doing so while threatened provokes attacks of opportunity.
It is possible to make a Concentration check to use a spelllike
ability defensively and avoid provoking an attack of
opportunity, just as when casting a spell. A spell-like ability can be
disrupted just as a spell can be. Spell-like abilities cannot be used
to counterspell, nor can they be counterspelled.
For creatures with spell-like abilities, a designated caster level
defines how difficult it is to dispel their spell-like effects and to
define any level-dependent variables (such as range and duration)
the abilities might have. The creature’s caster level never affects
which spell-like abilities the creature has; sometimes the given
caster level is lower than the level a spellcasting character would
need to cast the spell of the same name. If no caster level is specified,
the caster level is equal to the creature’s Hit Dice.
The saving throw (if any) against a spell-like ability is 10 + the
level of the spell the ability resembles or duplicates + the creature’s
Some spell-like abilities duplicate spells that work differently
when cast by characters of different classes—for example, true seeing.
A monster’s spell-like abilities are presumed to be the sorcerer/
wizard versions. If the spell in question is not a
sorcerer/wizard spell, then default to cleric, druid, bard, paladin,
and ranger, in that order.
Emphasis on somatic is mine. Unless it specifies otherwise such as the Warlock from Complete Arcane where it says on page 7 "Because the somatic components required for warlock invocations are relatively simple..." it means the SLA does not have any hand gesture requirements whatsoever.
So the question comes down to: Where do these spell-like abilities come from? And also what kind of limitations are placed on the form change, if any? As the Alter Self spell mentions, the creature retains its SLAs when changing forms but if it has a breath attack for example and the new form doesn't have a mouth then the breath attack doesn't work.