@article{,

title = {Effects of Tour Boats on Dolphin Activity Examined with Sensitivity Analysis of Markov Chains},

author = {Dans, Silvana Laura,Degrati, Mariana,Pedraza, Susana NoemÍ,Crespo, Enrique Alberto},

url = {http://dx.doi.org/10.1111/j.1523-1739.2012.01844.x},

issn = {1523-1739},

year  = {2012},

date = {2012-01-01},

journal = {Conservation Biology},

volume = {26},

number = {356},

pages = {708-716},

publisher = {Blackwell Publishing Inc},

abstract = {In Patagonia, Argentina, watching dolphins, especially dusky dolphins (Lagenorhynchus obscurus), is a new tourist activity. Feeding time decreases and time to return to feeding after feeding is abandoned and time it takes a group of dolphins to feed increase in the presence of boats. Such effects on feeding behavior may exert energetic costs on dolphins and thus reduce an individual's survival and reproductive capacity or maybe associated with shifts in distribution. We sought to predict which behavioral changes modify the activity pattern of dolphins the most. We modeled behavioral sequences of dusky dolphins with Markov chains. We calculated transition probabilities from one activity to another and arranged them in a stochastic matrix model. The proportion of time dolphins dedicated to a given activity (activity budget) and the time it took a dolphin to resume that activity after it had been abandoned (recurrence time) were calculated. We used a sensitivity analysis of Markov chains to calculate the sensitivity of the time budget and the activity-resumption time to changes in behavioral transition probabilities. Feeding-time budget was most sensitive to changes in the probability of dolphins switching from traveling to feeding behavior and of maintaining feeding behavior. Thus, an increase in these probabilities would be associated with the largest reduction in the time dedicated to feeding. A reduction in the probability of changing from traveling to feeding would also be associated with the largest increases in the time it takes dolphins to resume feeding. To approach dolphins when they are traveling would not affect behavior less because presence of the boat may keep dolphins from returning to feeding. Our results may help operators of dolphin-watching vessels minimize negative effects on dolphins.

Resumen: La observación de delfines, especialmente Lagenorhynchus obscurus, es una actividad turística nueva en Patagonia, Argentina. En presencia de barcos, el tiempo de alimentación disminuye y el tiempo para volver a alimentarse después de abandonar la alimentación y el tiempo que toma un grupo de delfines para alimentarse aumentan. Tales efectos sobre la conducta de alimentación puede implicar costos energéticos en los delfines y por lo tanto reducir la supervivencia y la capacidad reproductiva de un individuo o quizá asociarse con cambios en la distribución. Tratamos de predecir los cambios conductuales que más modifican el patrón de actividad de los delfines. Modelamos secuencias conductuales de delfines mediante cadenas de Markov. Calculamos las probabilidades de transición de una actividad a otra y las acomodamos en un modelo matricial estocástico. Calculamos la proporción de tiempo que los delfines dedicaron a una actividad determinada (presupuesto de actividad) y el tiempo que le llevó a un delfín reanudar esa actividad después de abandonarla (tiempo de recurrencia). Utilizamos un análisis de sensibilidad de cadenas de Markov para calcular la sensibilidad del presupuesto de tiempo y el tiempo de reanudación de la actividad a los cambios de las probabilidades de transición conductual. El presupuesto de tiempo para alimentación fue más sensible a los cambios en la probabilidad de que los delfines cambien de conducta de traslado a conducta de alimentación y de que mantengan la conducta de alimentación. Por lo tanto, un incremento en esas probabilidades pudiera ser asociada con la mayor reducción en el tiempo dedicado a la alimentación. Una reducción en la probabilidad de cambiar de traslado a alimentación también estaría asociada con los mayores incrementos en el tiempo que toman los delfines para reanudar la alimentación. Acercarse a los delfines cuando se están trasladando no afectaría menos su conducta porque la presencia del barco puede evitar que los delfines regresen a alimentarse. Nuestros resultados pueden ayudar a que los operadores de embarcaciones para observación de delfines minimicen los efectos negativos sobre los delfines.},

keywords = {activity budget, Argentina, disturbance, dolphin watching, dusky dolphins, impact, Lagenorhynchus obscurus, management, Patagonia, sensitivity analysis, stochastic matrix models, Threats, tourism, Whale watching},

pubstate = {published},

tppubtype = {article}

}

@article{,

title = {Dolphin Watching in Muscat, Sultanate of Oman: Tourist Perceptions and Actual Current Practice},

author = {Ponnampalam, Louisa S.},

url = {http://www.ingentaconnect.com/content/cog/tme/2011/00000007/00000002/art00003,https://doi.org/10.3727/154427311X13038402065866},

year  = {2011},

date = {2011-01-01},

journal = {Tourism in Marine Environments},

volume = {7},

number = {435},

pages = {81-93},

abstract = {Tourists who went dolphin watching in Muscat between December 2006 and June 2007 were asked to complete a questionnaire gauging the overall quality of their trips based on four main aspects: safety, educational value, perception of the boat driver's behavior, and overall satisfaction. Results showed that most tourists were satisfied with their dolphin-watching trip and that the majority felt that the boat drivers maintained a good distance between the boat and the dolphins, yet most also expressed the view that official guidelines should be established and implemented. However, awareness levels of tourists regarding the existence of dolphin-watching guidelines were low and tourist perceptions of their trips contrasted with observed practices, which reveal the current industry standards in Muscat to be lacking in many respects. The contrast is discussed and recommendations made for raising industry standards.},

keywords = {disturbance, dolphin watching, guidelines, impact, interview Survey, management, Oman, Perception, Questionnaire, Sea of Oman, Sultanate of Oman, tourism, Whale watching},

pubstate = {published},

tppubtype = {article}

}

@article{,

title = {The wrong spin on dolphins},

author = {Ellison, K.},

year  = {2009},

date = {2009-01-01},

journal = {Frontiers in Ecology},

volume = {7},

number = {366},

pages = {452},

abstract = {I was kayaking in a bay along Hawai’i’s Big Island when they surfaced: an undulating line of fins that suggested

why so many ancient explorers believed in sea monsters. The pod of spinner dolphins (Stenella longirostris) looked like

nothing so much as a dragon’s back, until one of the creatures leaped and twisted aloft, as if – it seemed to me, at least

– inviting admiration. My young son splashed into the water to swim with them, to my vicarious joy. Just seeing these wild creatures at such

close range was something we’d never forget. Only after returning to the pier did I notice the billboards posted by the

National Oceanic and Atmospheric Administration (NOAA). Half-hidden, these urged visitors to stay at least 50

yards away from the dolphins, and never to approach them. The rule is more than reasonable. The dolphins hunt in

deep water by night, using the shallow bay – where it’s easier to spot predators – to rest. Dolphins can

nap even while they’re swimming together. In other words, we were paddling through their bedroom.

Nor were we alone. Half a dozen other kayaks and a noisy tour boat were also following the dolphin pod

that afternoon. While not endangered per se, these cetaceans are certainly at risk of being run ragged by misguided human affection. Take this

to the extreme and you get Joan Ocean and the Sirius Institute, both based on the Big Island. Ocean’s website

describes her as a psychologist, shaman, and “authority on the subject of Dolphin Tel-Empathic Communication”. She

runs week-long excursions – for $1795 – in which participants progress from swimming with dolphins to “merging

with their group mind, their patterns of higher consciousness, and their telepathic visions and loving messages”.

(Incidentally, Ocean has recently branched out into reporting on her alleged encounters with “Sasquatch”.) Several years ago, Ocean was charged and fined under a

federal statute prohibiting harassment of marine mammals. Yet according to Jayne LeFors, NOAA’s point woman for

dolphin protection in Hawai’i, the fine amounted to less than the revenue generated by one seminar participant, and,

understandably, wasn’t much of a deterrent. The similarly fervent Sirius Institute champions the “dolphinization

of the planet”. Among other activities, it has developed a center for women to give birth underwater,

“assisted” by dolphins. The institute’s cofounder, Paradise Newland, says she gave birth to her own son while surrounded

by dolphins, and maintains that a dolphin healed the injured vertebrae in her neck with its sonar.

Reports of such “dolphin-assisted therapy” are increasing worldwide, despite strong indications that many of them

amount to dangerous wishful thinking. The internet is brimming with stories of dolphins supposedly mitigating symptoms of disorders,

 including cerebral palsy, Down’s syndrome, and autism. But in 2007, writing in Anthrozoös, the journal of the

International Society for Anthrozoology, two Emory University researchers warned that the trend is a “lose–lose”

proposition for both people and dolphins. They concluded that no valid evidence exists for any long-term benefit from

the therapy, while people who spend thousands of dollars to interact with dolphins not only lose money but put themselves

and the dolphins at risk of injury and infection. According to LeFors, Hawai’i’s dolphin-loving commerce has intensified in recent years, for several reasons. The law

meant to shield the creatures is not only toothless, but vexingly vague. As LeFors explained, “harassment” – defined as pursuit,

torment, and annoyance – is difficult to prove. “You almost have to be in the mind of the dolphin to know if

it’s being tormented or annoyed”, she added wearily. Furthermore, the dolphins may in fact approach swimmers

or boats in a seemingly playful manner, which LeFors compares to a child staying up watching videos,

long after bedtime. “They don’t necessarily know what’s good for them”, she explained. Another problem is a lack of data pointing to harm from

these activities. A 2006 study in Conservation Biology documented significant declines of bottlenose dolphins (Tursiops

truncatus) in Shark’s Bay, Australia, after several years of similar intrusions by tourists. LeFors suspects the Hawaiian

spinner dolphin population has also declined, a hunch that has led NOAA to commission research to explore this question.

Better data could help justify tighter restrictions. In 2004, Egypt set strict limits on swimming and boating in a

Red Sea bay frequented by spinner dolphins, after researchers demonstrated the toll from overenthusiastic

hordes of humans. As I learned to my embarrassment, it’s easy to misinterpret the charismatic dolphins. We see what we want to see, with

dolphins as with life. Where I’d anthropomorphically assumed their leaping in the air to be playful and friendly,

LeFors said it more likely meant they were annoyed at being disturbed. It’s a lot like that famous scene from The

Hitchhiker’s Guide to the Galaxy, in which the dolphins – after trying to warn humans about the planet’s impending

destruction, only to be cheered for their supposed antics – abruptly depart with},

keywords = {disturbance, Dolphin assisted therapy, dolphin watching, Hawaii, regulations, Spinner dolphin, Stenella longirostris, Threats},

pubstate = {published},

tppubtype = {article}

}