Detecting human impacts on wildlife and behavioral changes on marine mammals is time- sensitive, need sufficient resources, background information and investigations and analysis take time. Short-term behavior changes are caused primarily by disturbance. It is much more difficult to observe and analyze long-term behavioral disturbance and changes. In order to observe and analyze long term behavioral changes unconventional impact assessment research to identify disturbances and accurately inform wildlife management.

The topic of the article is long-term study of Indo-Pacific bottlenose dolphins (Tursiops truncatus). The research question is what are the long-term responses to dolphin-watching tourism? The data collection needed would be active field surveying. The field site is located in Shark Bay, Western Australia and so are approximately 2700 Bottlenose Dolphins. There are two types of dolphin tourisms in this bay. Since the 1960’s, dolphins have received fish handouts from humans and since 1993 commercial vessel based watching has occurred. The surveys gave GPS locations of individual dolphins and group location in correlation to landmarks. Tour vessels movements were tracked in 75 second intervals with GPS systems. The study was done over three consecutive 4.5 year periods. The calculations were made on actual locations and durations of all surveys and conducted during the study period.

Dolphin abundance is measured on individual identification of dolphins from photographic analyses. Statistical analysis was done by subdividing tourism and control sites into grid squares. Grid-square size was calculated as a smallest scale with acceptable error margin. Dolphin abundance was calculated per square per time period and a nonlinear logistic model was used. From the statistical tests it shows that dolphin watching has increased over the past few years and behavioral changes have increased.

LARS BEJDER,∗§§ AMY SAMUELS,† HAL WHITEHEAD,∗ NICK GALES,‡ JANET MANN,§RICHARD CONNOR,∗∗ MIKE HEITHAUS,†† JANA WATSON-CAPPS,§ CINDY FLAHERTY,‡‡∗∗∗AND MICHAEL KR¨UTZEN†††. Decline in Relative Abundance of Bottlenose Dolphins Exposed to Long-Term Disturbance. Conservation Biology. Volume 20. No. 6, 1791- 1798.