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Many studies have shown that the distribution of cetaceans can be closely linked to habitat, but the underlying function of the preferred habitats often remains unclear. Only when behavioural observations are made in relation to habitat types can functional mechanisms behind the habitat use be revealed. Within the range of a bottlenose dolphin (Tursiops truncatus) population off NE Scotland, dolphins show clear preferences for several discrete areas. If the observed patterns of distribution are related to foraging, we predict that behaviour patterns shown by dolphins would reflect this relationship. In this study we identify behaviours of dolphins at the water surface that were related to feeding events, evaluate whether the patterns of distribution were related to foraging and whether they were related the local submarine habitat characteristics. To investigate whether visible surface evidence of foraging behaviour varied spatially, we analysed data collected from 104 regular boat-based surveys made within the Moray Firth, NE Scotland, between 1990 and 2000. To determine whether underlying bathymetry had any influence on the surface behaviour of dolphins, a land-based observation study was carried out in the populations core region of use. The results of this study show that feeding behaviour by dolphins was significantly higher in areas used intensively by dolphins. Furthermore, there were clear relationships between feeding events and the submarine habitat characteristics; certain forms of feeding occur primarily over steep seabed gradients, and in deeper waters during June and July. These results quantitatively support the hypothesis that the distinctive patterns of distribution shown by these dolphins are related to foraging behaviour or opportunities, and that submarine habitat characteristics may be a significant factor in the foraging efficiency of dolphins. Future work should focus on collecting detailed information on the distribution patterns of prey within the study area to allow direct comparisons between predator and prey distributions.

This article discusses cetologist and natural historian Roy Chapman Andrews' research expeditions in the Pacific, observations of whale species and the Asian whale industry's use of whale by-products, and his successful attempts to turn natural history into a profitable business. Late 19th century science was subsidized by wealthy philanthropists and foundations which influenced the direction of research programs; Andrews incorporated scientific modernization into the whaling industry.

Archaeocete whales of the subfamily Dorudontinae (Cetacea, Basilosauridae) show strong evidence of having replaced upper and lower 1st deciduous premolars with permanent teeth late in their dental eruption sequence. This situation is rare in modern mammals, many of which have no teeth in the 1st premolar position or which retain a deciduous tooth in the 1st premolar position that is not replaced. Evidence for replacement of deciduous 1st premolars in dorudontine archaeocetes comes from both juvenile and adult specimens of Doruclon atrox from Egypt and Zygorhiza kochii from North America. Replacement of deciduous 1st premolars by permanent teeth may have been precipitated by a general delay in skeletal maturation found in cetaceans, which allowed dental development to proceed for a longer period of time than is generally available for most mammals.

The North Atlantic northern right whale (Eubalaena glacialis) is considered the most endangered large whale species. Its population has recovered only slowly since the cessation of commercial whaling and numbers about 300 individuals. We applied mark-recapture statistics to a catalog of photographically identified individuals to obtain the first statistically rigorous estimates of survival probability for this population. Crude survival decreased from about 0.99 per year in 1980 to about 0.94 in 1994. We combined this survival trend with a reported decrease in reproductive rate into a branching process model to compute population growth rate and extinction probability. Population growth rate declined from about 1.053 in 1980 to about 0.976 in 1994. Under current conditions the population is doomed to extinction; an upper bound on the expected time to extinction is 191 years. The most effective way to improve the prospects of the population is to reduce mortality. The right whale is at risk from entanglement in fishing gear and from collisions with ships. Reducing this human-caused mortality is essential to the viability of this population.

The existence of the finless porpoise, found in Japan and other parts of Asia, is being threatened by being caught incidentally in fishing nets. A new study seeks to determine the abundance of porpoise in Japan's Omura Bay, which is increasingly suffering from water pollution, and the effects of human activities on the species. Aerial surveys suggest that there are just 187 finless porpoise in the bay, raising concerns about their future viability.