Road surface layers of smaller stones, until the road surface was composed of small stones compacted into a hard, durable surface. "Road metal" later became the name of stone chippings mixed with tar to form the road surfacing material tarmac. A road of such material is called a "metalled road" in Britain, a "paved road" in Canada and the US, or a "sealed road" in parts of Canada, Australia and New Zealand. A granular surface can be used with a traffic volume where the annual average daily traffic is 1,200 vehicles per day or less. There is some structural strength if the
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