Dolphins

Studies of dolphin behaviour in response to dolphin watching tourism have shown changes in behavioural patterns in the presence of tourism vessels. A study conducted in Bunbury, Western Australia, revealed that the presence of a dolphin tour boat led to a marked decrease in the frequency of feeding and resting behaviours whilst increasing travelling. In addition, in 26% of the cases involving interaction dolphins responded negatively to the boat with aggressive or avoidance behaviour. In order to minimise harmful impacts on dolphin populations and ensure sustainable and pleasurable opportunities for tourists to watch them in the wild a number of guidelines (code of conduct) should be followed:

1. Do not exceed the speed of the slowest moving dolphin within 50 m of dolphins.
2. Do not allow vessels to proceed directly through a school of dolphins.
3. Do not approach dolphins closer than to within 50 m and interrupt contact unless animals leave the school to approach the vessel.
4. Females with calves should not be approached or pursued and should be avoided unless they approach the vessel to bow ride.
5. Interaction times with dolphin schools should not exceed 20 minutes.
6. Do not dive or swim with dolphins.
7. Do not feed dolphins

Picture courtesy of NOAA.

Indications of behavioural disruption similar to dolphin watching have been witnessed in studies of dolphin based tourism offering dolphin-swim charters. In the Bay of Islands, the swimmers enter the water as close as possible to the dolphins from the back of the tour boats and then swim freely in the ocean. The study, which started in 1994 and was completed in 1998, showed that dolphins do not like having swimmers placed in their path of travel, nor do they like having swimmers slip into the water directly on top of them (measured in both cases as an increase in avoidance behaviour). However, placing swimmers into the water off to the side of the dolphins reduced the animals' avoidance rate. Whenever dolphins did interact with the swimmers, then only 19% of the group participated and mostly involved juveniles.
Any country that allows swim-with-dolphin tourism, must ensure that the dolphins are given considerable time throughout the day when they're not exposed to tourism. Moreover, permitted interactions should be minimally invasive and a detailed education programme about the animals and threats to them should accompany any dolphin swimming tour.

Dolphin feeding programmes have also been shown to cause significant alterations in dolphin behaviour. A research project in Monkey Mia, Western Australia, where tourists feed wild dolphins showed that the mortality rate of provisioned animals (i.e. those that are hand fed) is significantly greater than non-provisioned animals. Of the 17 dolphin calves born to provisioned dolphins since 1975 only 5 (mortality rate of >70%). Of the 11 calves born since provisioning became regulated in 1986 only 2 survived (mortality rate of >80%). Research carried out between 1985 and 1993 investigating calf survival of provisioned females revealed a survival rate of 36% compared to 67% for offspring of non-provisioned females. The high mortality rate is thought to be due to pollution, pathogen-induced disease, high predation from shark attacks (due to social disruptions), and inadequate nutrition resulting directly or indirectly from the feeding programmes. Another contributing factor may be compromised maternal care. Evidence from dolphin feeding programs in Australia and the United States has also shown that dolphin feeding induces habituation and dependency in dolphins on the food provided by tourists. As a consequence, dolphins may be more persistent and aggressive in begging for food. A study of the dolphin-feeding program at Tangalooma, Queensland showed that dolphins regularly pushed tourists during feeding sessions.

Picture courtesy of NOAA.