Tarmac Group 1964, now group managing director, Martin acquired key quarrying assets, including Cliffe Hill Granite, Rowley Regis Granite and Hillhead Hughes. In 1968, Martin engineered the three way merger between Tarmac, Derbyshire Stone and the Scottish Asphalt company, William Briggs, creating the country's "largest roadstone and construction group". The group was briefly known as Tarmac Derby but the Derby name was later dropped. Further acquisitions were to come. Permanite, Britain's biggest roofing felt manufacturer, and Limmer, a quoted asphalt company, were bought in 1971, while the 1973 purchase of Mitchell Construction (which had foundered on the Kariba Dam) strengthened the construction
Cetacean surfacing behaviour present, particularly when they do not adhere to the regulations about approach. As an increase in SABs is beneficial to the whale watching tours’ participants, the tours may be encouraged to approach cetaceans closer than recommended by guidelines. There is a lack of understanding about the long-term effects of whale-watching on the behaviour of cetaceans, but it is theorised that it may cause avoidance of popular sites, or a decrease in the energy budget for individuals involved. Cetacean surfacing behaviour Cetacean surfacing behaviour or breaching is a group of behaviours demonstrated by the Cetacea infraorder when they come to the