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Recreational use of wild spaces is increasingly popular, resulting in a burgeoning tourism industry. Such activities can degrade the environment and disrupt the behaviour and natural function of organisms. A small population of bottlenose dolphins (Tursiops truncatus) is resident in Dusky Sound, New Zealand, a fjord with increasing human use. Dolphins, as top predators, play an important role within ecosystems and are at risk of long-term negative consequences from behavioural changes when exposed to high levels of vessel activity. A better understanding of the distribution of the dolphins in Dusky Sound would provide a framework for developing management within the fjord. Here we describe where dolphins were most frequently found, based on >40,000 km of photo-ID survey effort conducted over 10 years. Kernel density estimation revealed two large core areas that remained consistent over the duration of this study. This information could be used to determine areas within Dusky Sound where human activities around dolphins could be managed to avoid anthropogenically driven detrimental impacts. We suggest the following: (1) establish dolphin protection zones, (2) create a marine mammal sanctuary, (3) extend marine reserve boundaries, and/or (4) lower catch limits for fish within the fjord boundaries. [ABSTRACT FROM AUTHOR]

A small population of approximately 68 bottlenose dolphins, Tursiops truncatus, resident in Doubtful Sound, New Zealand, is subject to physiologically challenging conditions, and is exposed to anthropogenic pressure from tourism.A voluntary Code of Management incorporating dolphin protection zones (DPZs), in which tour boat access is limited, was established in 2008.Kernel density estimation (KDE) was used to quantify dolphin habitat use over a 13‐year period in order to describe seasonal variation in habitat use and consistency of habitat use over a decadal period, and to provide quantitative estimates of the extent of overlap between DPZs and core areas (50% volume contour) of habitat use.Habitat use varied seasonally, with the inner fjord area used more frequently in warmer months, and with a shift in use to the outer fjord in colder months. Patterns in habitat use were highly consistent over the 13‐year duration of the study.The spatial overlap between the area of core dolphin habitat and DPZs was low (<18%) overall, and some DPZs were rarely used during colder periods.Consistency in habitat use through time vindicates spatial management, but low overlap between core habitat and current DPZs suggests that an expansion of the DPZ areas would confer greater protection. [ABSTRACT FROM AUTHOR]