In recent years, marine mammals such as whales and more recently seals have increasingly been the focus of tourism operations. Whale watching now takes place in every continent and from countries as diverse as Argentina, South Africa, Japan, Norway, New Zealand and Tonga. It was estimated that the economic impact derived from whale-watching activities in 1995 totalled more than US$550 million.

The presence of tourist activity can cause a range of direct and indirect impacts on wildlife including: disturbance leading to changes in activity patterns, habituation, aberrant social behaviour, dietary distortions, reduced fitness and reproductive output, increased predation, altered community structures, desertion of home ranges, and habitat alterations and pollution. Behavioural disturbance has been recorded in studies investigating the impacts of marine mammal based tourism. For example, a study of the behavioural responses of humpback whales to whale watching vessels near Juneau, Alaska revealed that individuals followed by whale watching boats showed greater variance in time spent at the surface and surface related behaviours than whales that were not being pursued. Wildlife responses to tourists can range from minor aberrations in normal behaviour patterns to clear indicators of agitation or stress such as retreat from tourist vessels. Impact of whale watching vessels on the animals will depend on the number of visits made in a day and the distance left between boats and whales. In Hualien, since the first whale watching business opened in 1997, the number of whale watching boats has increased to 25 and expanded to Ilan, Taitung, Pingtung, Taipei and Taichung. Surveys have indicated that most whale watching boats observed whales and dolphins from about 100m, some drawing as close as 50m to the animals. A handful of captains were reported to chase or besiege dolphins for close-up observation. Moreover, several whale-watching boats usually tended to arrive simultaneously at the same area during the peak period between July to October, causing obvious disturbance to the animals. These behavioural responses have only been observed short-term and cannot yet be quantified in terms of long-term impacts. Nevertheless, subtle chronic effects could potentially be detrimental to wildlife populations.

Picture courtesy of Topham.

In order to minimise harmful impacts on cetacean populations and ensure sustainable opportunities for watching or interacting with cetaceans in the wild a number of guidelines (code of conduct) should be followed:

1. Do not place vessels in the path of an approaching whale.
2. Approach whales as slowly as possible and avoid sudden changes of speed or direction.
3. Maintain a minimum of a 100-m between the vessel and any whale at any time.
4. Limit close contact (100m) to 15 minutes.
5. Take special care with mothers and their calves.
6. Do not restrict the movement or behaviour of whales. Anchorage within 300 m of a whale is prohibited.
7. Do not use echo sounders.
8. Do not allow swimmers and divers to enter the water or be closer than 300 m from any whale.
9. Do not playback any kind of underwater sound.
10. Do not allow passengers to touch or attempt to feed whales or any garbage in the sea.