Complex sentence: The animals are looked after by their owners and the Agisters employed by the Verderers of the New Forest--the Verderers are a statutory body with ancient roots, sharing the management of the forest with the Forestry Commission and National park authority.
Split into simpler sentences: The animals are looked after by their owners and by the Agisters employed by the Verderers of the New Forest. The Verderers are a statutory body with ancient roots, who share management of the forest with the Forestry Commission and National park authority.