The response of marine tucuxis(Sotalia fluviatilis)towards tourist boats involves avoidance behaviour and a reduction in foraging

Abstract

Marine ecotourism has undergone worldwide expansion in recent years, leading to increased concern regarding the impact on the environment. Despite this, however, few studies into the potential effect of tourist boats on dolphin welfare, have been carried out. In order to evaluate the impact of these activities on the presence and foraging behaviour of the threatened marine tucuxis (Sotalia fluviatilis), we observed them: 1) prior to the arrival of a boat in the bay; 2) for the duration of a vessel's stay in the bay and 3) after the boat's departure: ie pre-exposure, exposure and post-exposure phases. Both the average number of dolphins and the foraging activity were significantly reduced while a vessel was in the bay. Marine tucuxis are exclusively coastal and show fidelity to the site where they choose to live which makes any environmental disturbance of particular importance. Moreover, our findings are further evidence of the need for motorboat activity to be regulated and monitored to protect marine tucuxis as well as other coastal and estuarine dolphins.

The non-consumptive economic value of wildlife: the case of three cetacean species

“…This has occurred in a range of whale-watching destinations, where behavioural changes have been observed, such as diving behaviour alterations, acoustic communication disruption, group cohesion loss, swimming speed and direction alteration, and modifications to feeding and resting patterns (Corkeron 1995, Foote et al 2004, Bejder et al 2006, Timmel et al 2008, Visser et al 2011). Disturbance has also been linked to cetaceans temporarily or permanently abandoning areas (Bejder et al 2006, Carrera et al 2008, which can have significant economic consequences from the companies' perspective but can also have ecological implications in terms of ecosystem functioning (Roman et al 2014). In addition to the immediate responsive effects, all the listed short-term behavioural changes resulting from irresponsible and non-sustainable whale-watching practices can ultimately lead to long-term negative effects on cetacean population dynamics and individual fitness loss.…”

Behaviour and occurrence of the Antillean manatee (Trichechus manatus manatus) in relation to habitat characteristics and the influence of human activities in a protected area in north‐eastern Brazil

“…However, such limitations regarding the wild manatees is not unusual: observing aquatic mammals in nature and in murky waters is known to be a challenging task (e.g. Carrera et al, 2008;Silva et al, 2011;Magera et al, 2013).…”