Baiting sharks for marine tourism: Comment on Clua et al. (2010)

Brunnschweiler, Juerg M.; McKenzie, J. L.

doi:10.3354/meps08877

Cited by 6 publications

(3 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Provisioning food is a means of attracting wildlife to facilitate human interaction, and though it is a widespread practice, its long-term ecological implications need further investigation ( Orams, 2002 ; Dobson, 2006 ). Reliable shark encounters are difficult, promoting the use of provisioning activities to attract them ( Gallagher & Hammerschlag, 2011 ; Hammerschlag et al, 2012 ) These are controversial as sharks are apex predators, and some provisioned species are potentially dangerous to humans and may impact their ecological function ( Brunnschweiler & McKenzie, 2010 ). In the Red Sea, tagged silky sharks, Carcharhinus falciformis , had modified local habitat use and increased presence on days when baiting occurred ( Clarke, Lea & Ormond, 2011 ).…”

Section: Introductionmentioning

confidence: 99%

Population structure and residency patterns of whale sharks,Rhincodon typus, at a provisioning site in Cebu, Philippines

Araújo

Lucey

Labaja

et al. 2014

PeerJ

103

View full text Add to dashboard Cite

This study represents the first description of whale sharks, Rhincodon typus, occurring at a provisioning site in Oslob, Cebu, Philippines. Frequent observations of sharks are often difficult, even at tourism sites, giving rise to provisioning activities to attract them. The present study provides repeated longitudinal data at a site where daily provisioning activities took place, and whale sharks were present every day. A total of 158 individual whale sharks were photographically identified between Mar 2012 and Dec 2013, with 129 males (82%), 19 females (12%) and 10 (6%) of undetermined sex. Mean estimated total length was 5.5 m (±1.3 m S.D.). Twenty individuals were measured with laser photogrammetry to validate researchers’ estimated sizes, yielding a good correlation (r2 = 0.83). Fifty-four (34%) individuals were observed being hand-fed by local fishermen (provisioned), through in-water behavioural observations. Maximum likelihood methods were used to model mean residency time of 44.9 days (±20.6 days S.E.) for provisioned R. typus contrasting with 22.4 days (±8.9 days S.E.) for non-provisioned individuals. Propeller scars were observed in 47% of the animals. A mean of 12.7 (±4.3 S.D.) R. typus were present in the survey area daily, with a maximum of 26 individuals (Aug 10 2013) and a minimum of 2 (Dec 6 2012). Twelve (8%) individuals were seen on at least 50% of survey days (n = 621), with a maximum residency of 572 days for one individual (P-396). Twenty four individuals were photographically identified across regional hotsposts, highlighting the species’ migratory nature and distribution. Extended residency and differences in lagged identification rates suggest behavioural modification on provisioned individuals, underlying the necessity for proper management of this tourism activity.

show abstract

Section: Introductionmentioning

confidence: 99%

Population structure and residency patterns of whale sharks,Rhincodon typus, at a provisioning site in Cebu, Philippines

Araújo

Lucey

Labaja

et al. 2014

PeerJ

103

View full text Add to dashboard Cite

show abstract

“…However, recent work has demonstrated that observational techniques may be prone to some bias (Meyer et al. 2009a,b; Brunnschweiler & Baensch 2010; Brunnschweiler & McKenzie 2010) and reinforce the need for remote monitoring tools, particularly acoustic and satellite telemetry, to evaluate the ecological impacts of ecotourism on shark behaviour (Sims 2010; Hammerschlag, Gallagher & Lazarre 2011). To our knowledge, only four published studies have used telemetry to address these issues, with conflicting results.…”

Section: Introductionmentioning

confidence: 99%

“…However, at present, the debate has been largely rhetorical because of lack of sufficient quantitative data to either support or refute various hypotheses regarding apex predator conditioning and behaviourally or ecologically mediated effects (Meyer et al. 2009b; Brunnschweiler & McKenzie 2010).…”

Section: Introductionmentioning

confidence: 99%

Don’t bite the hand that feeds: assessing ecological impacts of provisioning ecotourism on an apex marine predator

Hammerschlag¹,

Gallagher²,

Wester³

et al. 2012

Functional Ecology

138

148

View full text Add to dashboard Cite

Summary1. There has been considerable debate over the past decade with respect to wildlife provisioning, especially resultant behavioural changes that may impact the ecological function of an apex predator. The controversy is exemplified by the shark diving industry, where major criticisms based on inference, anecdote and opinion stem from concerns of potential behaviourally mediated ecosystem effects because of ecotourism provisioning (aka 'chumming' or feeding).2. There is a general lack of empirical evidence to refute or support associated claims. The few studies that have investigated the behavioural impacts of shark provisioning ecotourism have generated conflicting conclusions, where the confidence in such results may suffer from a narrow spatial and temporal focus given the highly mobile nature of these predators. There is need for studies that examine the potential behavioural consequences of provisioning over ecologically relevant spatial and temporal scales. 3. To advance this debate, we conducted the first satellite telemetry study and movement analysis to explicitly examine the long-range migrations and habitat utilization of tiger sharks (Galeocerdo cuvier) originating in the Bahamas and Florida, two areas that differ significantly with regards to the presence ⁄ absence of provisioning ecotourism. 4. Satellite telemetry data rejected the behaviourally mediated effects of provisioning ecotourism at large spatial and temporal scales. In contrast, to the restricted activity space and movement that were hypothesized, geolocation data evidenced previously unknown long-distance migrations and habitat use for both tiger shark populations closely associated with areas of high biological productivity in the Gulf Stream and subtropical western Atlantic Ocean. We speculate that these areas are likely critically important for G. cuvier feeding forays and parturition. 5. We concluded that, in the light of potential conservation and public awareness benefits of ecotourism provisioning, this practice should not be dismissed out of hand by managers. Given the pressing need for improved understanding of the functional ecology of apex predators relative to human disturbance, empirical studies of different species sensitivities to disturbance should be used to guide best-practice ecotourism policies that maximize conservation goals.

show abstract