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The current study aims to assess current impacts of whale watching activities on sperm whales off Kaikoura. We have attempted this using three platforms: a small quiet boat, a shore based lookout station and the tour vessels themselves. Each of these platforms have their distinct and complementary advantages and disadvantages (Bejder and Samuels 2003). By using all three in this study (see Chapters 2-4), we can capitalize on their strengths and hopefully address their weaknesses. Surface behaviour can be readily observed and recorded, and statistical tests can reveal whether any differences are statistically significant. What is ultimately important though is the biological significance of any effects and it is therefore desirable to be able to measure behaviors which are likely to have a direct biological significance (NRC 2005). Sperm whales come to Kaikoura to feed and feeding efficiency is likely to be of prime biological significance for these animals. Sperm whale feeding occurs at depths of hundreds of meters and has never been directly observed. However, sperm whales echolocate to find their prey and as we come to understand their echolocation behaviour better we can begin to infer their underwater behaviour, including their foraging rates, by analysing acoustic recordings made at the surface. This is a much more involved process than simply logging simple surface behaviours. However, in this project we attempt to get at this crucial question by comparing measures of acoustic behaviour associated with feeding success with and without the presence of whale watching platforms. Shore based results: Observations were made during 212 days between April 2010 and June 2011. A total of 2,717 surfacings were recorded using the theodolite and 1,204 surfacings using the digital video-binocular system. Both surface behaviour and distribution of whales varied seasonally. Blow interval and surface time peaked in summer, while swimming speed, distance from shore and water depth peaked in spring, when whale use of the Kaikoura Canyon area also appeared to decrease. Whales observed from shore were generally accompanied by tour vessels less than half the time. The greatest level of visitation occurred in the afternoon and during the summer months, when the number of whale surfacings accompanied by vessels slightly exceeded the number of whale surfacings unaccompanied by vessels. GIS analysis of whale and tour vessel distribution showed whale sightings were most tightly clustered in summer and autumn when the degree of overlap between areas where whales were accompanied and unaccompanied by boats peaked at 78-93%. There was a significant difference in ventilation rate (blow interval) for whales in the presence versus absence of whale watching vessels, but no difference in surface behaviour with number of vessels present. Swimming speed did not vary with vessel presence. Tour boat platform results: The distance between whale watch tour vessels and whales during an encounter averaged 75 ± 1.8m (mean ± se). Sperm whales changed heading >10° during 75% of interactions with whale watch vessels. Neither heading changes nor blow intervals varied significantly with distance of whales from the whale watch vessels. To obtain general data on vessels, GPS data loggers were deployed onboard whale watching vessels and aeroplanes from Spring 2009 through Winter 2011. Additional data for aerial tours were downloaded from online GPS track logs. GPS tracks showed less activity in winter than other seasons, with summer and autumn the busiest seasons. Tours ranged furthest offshore and alongshore in spring, when the sperm whales were relatively scarce. Tours occurred across the narrowest ranges in winter. Effects of vessel traffic on indivdiually identfied whales' surface behaviour: Respiratory parameters were not affected by the presence of whale watching vessels. Differences between individuals and seasons were the most consistently important factors. In the analyses of spatial behaviour, only the variance of heading changes increased in the presence of vessels. These results indicate that sperm whales seem not to react to the presence of whale watching vessels with changes in respiratory and most spatial behaviours. However, the small proportion of transient whales in our sample, and the fact that there are reactions, leads us to interpret this lack of response cautiously. Noise from WW Vessels: Recordings, using five hydrophones, were made in the deep water of Kaikoura Canyon during both regular vessel transit and controlled vessel passes. Underwater recordings were made continuously during passes, while the speed and distance of the whale watch vessel was obtained from an onboard GPS data logger and laser range finding binoculars. Source levels were calculated for 1/3 octave frequency bands and two wider bands, one of which was the band in which sperm whales may be more sensitive. For such large, powerful vessels, the jet propelled catamarans used by whale watch tours at Kaikoura were remarkably quiet, especially when making the sort of manoeuvres required to stay with whales at the surface. Favourable noise characteristics of the newer jet propelled vessels may be contributing to reduced levels of disturbance among sperm whales at Kaikoura, despite vessel sizes having increased since previous studies. Effects of WW on underwater acoustic behaviour of whales: Foraging is likely the most biologically significant activity for sperm whales that are the focus of whale-watching at Kaikoura. Foraging success is therefore a key behaviour to monitor changes that have direct impact on the whales’ fitness in the area. We are now able to measure foraging effort and prey detection rates using passive acoustics. In this chapter, we measure the acoustic foraging behaviour of whales before, during and after viewing by different numbers and types of whale-watching vessels. We found no differences in parameters that we believe are most closely related to prey encounter rates and feeding success that could be attributed to vessel interactions. There were slight changes to the initial search pattern of dives following whale-watching boat encounters: whales delayed their first click and descended for longer before stopping for their first silence, which was also extended. However, the effects appeared small relative to high individual variability and were within the range of behaviours predicted by their spatial and temporal environment