Anthropogenic contaminants in the marine environment often biodegrade slowly, bioaccumulate in organisms, and can cause reproductive, immune, and developmental effects on wildlife; however, their effects on cetacean health and behavior have not been extensively studied. This study aims to expand knowledge concerning concentrations and biological effects of endocrine disrupting contaminants and essential and non-essential inorganic elements in stranded cetaceans. We evaluated tissue samples and pathology data from 66 odontocetes that stranded in the southeastern United States during 2012– 2017. Using mass spectrometry blubber samples were analyzed for five endocrine disrupting contaminants (atrazine, bisphenol-A, diethyl phthalate, nonylphenol ethoxylate, triclosan), and liver samples were analyzed for 12 inorganic elements (As, Cd, Co, Cu, Mg, Mn, Fe, Pb, Hg, Se, Tl, Zn). Results from this study demonstrate that exposure to certain contaminants may be associated with subtle or sublethal cellular changes in free-ranging marine mammals that could contribute to health declines or stranding. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2019. / FAU Electronic Theses and Dissertations Collection

As human impact on marine ecosystems continues to grow, so too does the need for sound conservation and management strategies that are informed by science. Cetaceans, the whales, dolphins and porpoises, epitomise this challenge, because they are hard to study, they have been heavily exploited in the past, and because some of their habitats, behaviours and life-history strategies make them acutely vulnerable to human activities. Unfortunately, research on free-ranging cetaceans in remote areas is costly, and financial resources are limited. The approach used in this thesis to acquire inexpensive quantitative information on cetacean populations and behaviour was to seek out platforms of opportunity. Tourism and environmental education projects provided access to remote areas of importance to cetaceans. The topic was explored in two main areas. First, studies were conducted to investigate the use of ships of opportunity in estimating distribution and abundance, namely of Antarctic baleen whales. The second area of interest was the effect of boats on killer whales in the northeast Pacific. Platforms of opportunity proved valuable for collecting data to model the role of measurement error on abundance estimation. Measurement error was found to be a potential source of bias in four distance estimation experiments. Platforms of opportunity could be used to train observers on protocols, and to learn to use range- finding photogrammetric equipment well before conducting dedicated surveys, which would eliminate this source of bias, as well as estimating abundance in some cases. Abundance and distribution of three whale species were modelled using data collected aboard Antarctic tourist ships. Spatial modelling techniques were used to model distribution of minke, fin and humpback whales using line-transect data collected from a survey that could not be randomised. Strong gradients in animal density were predicted, which could be used to inform future surveys. In the meantime, rough estimates of abundance were obtained, and this approach shows promise for other areas where lack of resources makes systematic surveys prohibitively expensive. A government-funded environmental education project provided logistical support for two studies that dealt with effects of boats on killer whale behaviour. One quantified the extent to which a particular style of whalewatching was disruptive to whale behaviour, and commercial whalewatchers agreed to halt this activity. The other found that a protected area conferred benefit to killer whales, even though it protects only a fraction of the whales' habitat for a fraction of the year. The thesis contains four case studies that illustrate how inexpensive methods may be used to obtain practical quantitative information to aid decision-making about conservation and management of wild cetaceans that interact with (i.e., whalewatching), compete with (i.e., fishing) or are exploited by (i.e., whaling) humans.

The most recent study on cetaceans in Algoa Bay, South Africa, was conducted over 14 years ago. Consequently, knowledge of the cetacean species visiting this bay is currently based on incidental observations and stranding data. A number of developments in recent years: a deepwater port, proposed oil refinery, increased boating and fishing (commercial and recreational), a proposed Marine Protected Area, and the release of a whale-watching permit, all of which may impact these animals in some way, highlight the need for a baseline study on cetaceans. Therefore, the aim of this study was to determine the spatial and temporal distribution, and habitat preference of cetaceans in Algoa Bay. Boat-based surveys were conducted monthly between March 2009 and July 2010. At each sighting the GPS location, species, group size and composition, and behaviour were recorded. Using GIS, the sighting data was related to data layers of geographical variables such as sea surface temperature, depth and sea-floor substrate. Approximately 365 hours of search effort were completed over 57 surveys, with a total of 346 sightings. Species observed were: southern right whales (Eubalaena australis), humpback whales (Megaptera novaeangliae), Bryde’s whales (Balaenoptera brydei), Indian Ocean bottlenose dolphins (Tursiops aduncus), Indo-Pacific humpback dolphins (Sousa chinensis), and longbeaked common dolphins (Delphinus capensis). Southern right whales were observed during austral winter, utilising the shallow, protected areas of the bay as a mating and nursery ground. Humpback whales were also recorded extensively during winter, in more offshore waters, with a significant number of mother-calf pairs sighted. Bryde’s whales were recorded in offshore waters during summer and autumn, where they were primarily observed travelling and foraging. Bottlenose dolphins were the most prolific species sighted. They were recorded year-round throughout the inshore waters of the bay, with large group sizes (up to 500 animals), and displayed a wide variety of behaviours. Humpback dolphins were observed in extremely shallow and inshore waters (mean bottom depth of 6.6 m) along the south-west corner of the bay, in small groups of approximately three individuals. Common dolphins were the least observed species, and were mainly observed foraging in large groups of up to 800 individuals. The results of this study indicate how cetaceans utilise the bay in significantly different ways. Geographical and anthropogenic factors have influenced the spatial and temporal distribution of these animals and have resulted in habitat preferences, as well as potential key habitats, in the bay. Thus, this study has provided baseline information for future research and for better informed conservation and management strategies in Algoa Bay.