DOG catchers will be scouring the Kuomintang stronghold of Rennie's Mill for strays before clearance workers move in to tear down the Sai Kung slum area next month. Dogs have become pests since their former owners dumped them on the hillside after moving to high-rise public estates. Former residents have been rehoused in Hau Tak Estate in Junk Bay, where more than 1,500 rental units in two blocks have been reserved for them. But dogs are banned on public housing estates. The number of abandoned dogs has grown as the clearance D-day approaches, sparking off fears for the safety of clearance workers. It is estimated one-third of the 1,900 families there kept dogs, according to the RSPCA. But owners have ignored repeated calls to surrender their pets. The RSPCA could only collect a couple of dogs in a campaign last summer. So far dog-catcher patrols have netted 66 stray dogs. The first phase of the clearance is scheduled next month, covering most of the southern parts of the cottage area. About 30 families affected by the first phase have not yet accepted Government compensations. The second phase is due to begin in July. About 90 per cent of the Rennie's Mill households have accepted compensation or rehousing terms.