They were unable to determine the condition of around half of the features of all sites (for example habitat quality or number of species) due to insufficient evidence.
Nid oedd yn bosibl iddynt benderfynu ar gyflwr tua hanner nodweddion yr holl safleoedd (er enghraifft ansawdd cynefinoedd neu nifer y rhywogaethau) oherwydd nad oedd digon o dystiolaeth.