Publisher :
Place of publication :
Publication year : 2009
Thematic : Ecotourism
Language : English
Note
Wildlife tourism alters the environmental conditions in which the focal animal lives, and it is therefore
necessary to assess the ability of the animal to adjust to and persist in these novel conditions if the industry
is to be sustainable. Here, we report on the physiological responses of southern stingrays (Dasyatis
americana) which are the focus of intense marine provisioning-tourism in the Cayman Islands. Using
stingrays from non-tourist sites about Grand Cayman as a basis for comparison, we show in this natural
experiment that tourist-exposed stingrays exhibit hematological changes indicative of physiological
costs of wildlife tourism. The novel conditions with which the stingrays must interact include non-natural
food, higher injury rates (from boats, conspecifics and predators), and higher parasite loads (from
crowding conditions). As a result of this year-round environment, stingrays display sub-optimal health:
lower hematocrit, total serum protein concentrations, and oxidative stress (i.e., lower total antioxidant
capacity combined with higher total oxidative status). Moreover, they show evidence of attenuation of
the defense system: for tourist stingrays only, animals possessing both injuries and high parasite loads
also exhibit lowest leukocrit, serum proteins and antioxidant potential, as well as differing proportions
of differential leukocytes indicative of suppression (lymphocytes and heterophils) and down-regulation
(eosinophils), thus suggesting that the physiological changes of tourist stingrays are in partial response
to these stressors. While survival- and reproduction- quantification was not possible in this long-lived
marine species, the physiological measures -situated within ecological context, indicate that the longterm
health and survival of tourist stingrays have a significant probability of being affected. Consequently,
management of the tourism attraction is essential. The indicators chosen in this study reflect
general health indices and defense capabilities used across taxa, and represent a tradeoff between ease
of collection/analysis and interpretation so that managers can continue the research for monitoring
purposes.
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Keywords : marine pelagic realm
Encoded by : Pauline Carmel Joy Eje
