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The urbanization of cities has drastically altered the way in which species interact with their environment. Some species have managed to adapt well to habitat modification (McIntyre et al., 2001; Bonier et al., 2007), and some can even thrive in urban areas because of their tolerance for local ecological shifts (Shochat et al., 2006). For instance, non-native and invasive species that exhibit generalist characteristics and are therefore free from the constraints that regulate natural populations thrive during disturbance and habitat modification (McKinney & Lockwood, 1999). In contrast, the homogenization of urban ecosystems may influence the ability for some species to cope with anthropogenic changes (McKinney, 2002, 2006), causing a rapid decrease in population or local extinction (e.g., invertebrates: Fattorini, 2011; mammals: Davidson et al., 2009; and birds: Devictor et al., 2007).
Top predators are of particular interest in studying ecosystems of any kind. As such, marine mammals may serve as a sentinel species and, therefore, are an important group to study in relation to climate change, water quality, and other anthropogenic effects. They access busy commercial ports around the world and must contend with the challenges of acoustic noise and boat traffic from commercial shipping (Moore & Clarke, 2002; Kent et al., 2012), recreational boating (Buckingham et al., 1999; Graham & Cooke, 2008), ecotourism (Wilke et al., 2005; Allen et al., 2007), dredging (Pirotta et al., 2013), and local commercial fishing (Lewison et al., 2004), as well as increased pollution (Parsons, 1998). It is likely that the interaction of all these anthropogenic activities contributes to the decline of local populations such as in the case of the IndoPacific bottlenose dolphins (Tursiops aduncus) in Western Australia (Ansmann et al., 2013).
In even smaller and more geographically isolated populations, the effects of potentially harmful anthropogenic activities can contribute to a steady and critical decline, as in the case of the vaquita (Phocoena sinus) whose current total population has been estimated to be approximately 30 individuals (Taylor et al., 2016; Jaramillo-Legorreta et al., 2017), or to the extinction of an entire species such as the baiji (Lipotes vexillifer), which is now considered to be functionally extinct from its habitat of the Yangtze River in China (Turvey et al., 2007). However, population recovery may occur, but it often varies...
