There is a general perception that sharks are at high risk. Through a questionnaire, however, I show that shark experts have different perceptions on the management and conservation status of this group. Most respondents were aware of cases of shark population collapses and recoveries. However, there was no uniform perception of the level at which populations collapse or recover. Though most respondents were aware of cases of successful management of shark populations, most believed that successful management stories are not well communicated to the general public. Experts with a fisheries background rightfully agreed that sharks can be fished sustainably and hence disagreed that only the highly productive species can be fished sustainably. In contrast, most experts from other fields gave contradictory responses, agreeing with both statements. The questionnaire findings suggest a possible communication gap that should be bridged to better inform the public debate.

 • Shark

 •  Stock status

 • Conservation

 • Fisheries

 • Communication gap

Braccini M (2016) Experts have Different Perceptions of the Management and Conservation Status of Sharks. Ann Mar Biol Res 3(1): 1012

General perceptions can influence conservation and resource management policy. For example, in response to an intense social media campaign led by international conservation groups, Green politicians, and recreational fishers, the Australian government imposed a moratorium on the operations of a factory trawler. This overrode the government’s own independent fisheries management process; science-based fisheries management advice took a back seat to protest by interest groups, culminating in a contentious political decision [1]. This shows that public perceptions in the case of the Australian example, that the use of large vessels leads to over fishing do not necessarily agree with scientific evidences that the catch quota allocated to this vessel was sustainable. Perceptions can therefore have a strong influence in the process of making decisions in natural resource management.

Public perception on sharks has changed from one that we need to protect humans from sharks to one where we must protect sharks from humans [2]. This current perception has been largely triggered by the considerable media attention generated from various studies reporting dramatic declines in some shark populations. For example, a recent study by [3] in Marine Policy reporting the overall poor status of shark populations was the journal’s most downloaded article in 2013 and yielded ~272,000 results in a Google search done in June 2016. It is evident that shark conservation is a topical issue with the global conservationmovement being stimulated by the interaction between social media and the increasing access to science [4].

Between 2?6 June 2014 I attended Sharks International 2014, held in Durban, South Africa. It was a forum for the world’s leading shark and ray scientists and students to meet and report on research findings on a whole range of shark research fields. This conference provided a unique opportunity to assess the perception of shark experts on the conservation and management of sharks worldwide. In this study, I summarise the main findings from a questionnaire sent to the conference delegates and show that there is no overall unanimous consensus on the status of sharks. 

The questionnaire (Figure 1)

Figure 1 Questionnaire sent to conference delegates

was emailed to the 301 email addresses included in the conference program. For questions #7?11, response patterns were explored through generalised linear models (GLMs). Model predictors included gender, age category, affiliation, education level, years of experience, and field of expertise. A binominal distribution was used for questions #8 and #11. Question #7 was not analysed due to a lack of contrast in the responses (98% of respondents answered ‘Yes’). A quasibinomial distribution was used for questions #9?10. The Likert-type questions were analysed using contingency tables. For these questions, due to poor or no replication for some of the response options, responses were regrouped in three categories:‘agree’ (for ‘agree’ and ‘strongly agree’), ‘neither’ and ‘disagree’ (for ‘disagree’ and ‘strongly disagree’). Furthermore, for the statements “Shark and ray species can be fished sustainably” and “Only highly productive shark and ray species can be fished sustainably” the former is the correct response [5,6]. Hence, response patterns were studied for the following combination of responses: agree-agree, agree-neither, and agree-disagree. A similar approach was applied for the statements ‘Shark and ray species are overfished’ and ‘Some shark and ray species are overfished’ where the latter is the correct response [7]. Finally, some of the predictor levels were also combined due to lack of contrast (for ‘Field of expertise’, ‘Physiology’, ‘Genetics’ and ‘Policy’ were combined with ‘other’ and for ‘Affiliation’, ‘Private’ was combined with ‘other’

 Sixty experts answered the questionnaires. Most of the respondents were male (62%), had between 26 and 40 years of age (63%), an university affiliation (52%) and more than 10 years of experience in their field of expertise (43%) (Figure 2).

Figure 2 Distribution of socio-demographic variables and a comparison of the research area of conference presentations and of the delegates responding the questionnaire. Cons.B., Conservation Biology; Fi, Fisheries; Gen., Genetics; M.E., Marine Ecology and Biology; Phy., Physiology; Pol., Policy and Management.

Also most of the respondents had a Masters or PhD degree (83%). Although most of the papers presented at the conference where on the marine ecology and biology of sharks (37%), more than half of the questionnaire respondent had a fisheries or conservation biology background (55%). Questionnaire responses showed that experts across different research fields have different views on the management and conservation status of sharks. Most respondents were awareof cases of shark population collapses and recoveries, and of cases of successful management of shark populations (Figure 3).

Figure 3 Distribution of questionnaire responses. Bu is the unfished biomass

Hence, there were no significant patterns in these responses across respondents’ gender, age category, affiliation, education level, field of expertise, or years of experience (Table 1). There were no significant patterns in the definition of population collapse or recovery (Table 1).

Respondents had a wide range of perceptions of when a population collapses (between 5 and 65% of the unfished level, Bu ) (Figure 3). The majority of respondents, however, considered a collapsed population when at 20?30% Bu . Respondent’s definition of population recovery ranged between 30 and 100% Bu with modes at 40?50% and 70?80% Bu (Figure 3).

Most respondents agreed that sharks as a group can be fishedsustainably but also agreed that only the highly productive species can be fished sustainably (Figure 3). Further exploration of these two statements showed significant differences among respondents from different fields of expertise (P=0.025). Most respondents with a fisheries background correctly agreed that sharks and rays can be fished sustainably and hence disagreed that only the highly productive shark and ray species can be fished sustainably. In contrast, most respondents from other fields of research agreed with both statements. No other significant patterns were observed. Finally, 19% of respondents believed that shark cannot be fished sustainably; of these, the majority (82%) had a non-fishery background.

Most respondents strongly agreed that only some sharks are overfished but also agreed that sharks as a group are overfished (Figure 3). Further exploration showed no significant patternsin responses across any of the predictors considered (P>0.05). Interestingly, most of the interviewees disagreed with the statement that fishery scientists are good at communicating cases of successful fishery management. There was a marginally significant (P=0.047) pattern with age but this was due to the responses of the 55 age categories which had the smallest sample sizes.

The interviewed experts showed different perceptions on the management and conservation status of sharks. Most respondents were aware of cases of population collapses and recoveries, and of successful management. This is in agreement with the scientific literature [8] where cases of collapse, recovery and successful management have been documented and hence made available to the scientific community. Respondents, however, showed a wide range of perceptions of when a population collapses or recovers. The wide range of responses contrasts with current practices in fishery sciences where stock performance indicators, such as spawning biomass, are used as benchmarks or reference points (RP) to define stock status. RP consist of limits (representing an unacceptable boundary which, if breached, triggers immediate significant management actions), targets (representing the optimum state to deliver economic and/ or social objectives) and thresholds (an intermediate level used as an ‘early warning’ so management actions are implemented before reaching limit levels) [9]. For shark populations with high productivity (e.g. gummy and whiskery sharks), limit RP (a proxy for population collapse) can be set at 25?30% Bu . However, for populations with low productivity (e.g. dusky and sandbar sharks) limits should be set higher, ranging 36?37% Bu [10]. In turn, threshold RP (a proxy for population recovery) can be set at 34?41% Bu for populations with high productivity but at 48?49% Bu for populations with low productivity [10]. Similar patterns occur for teleost populations with high and low productivity [11]. In contrast, some respondents considered a population to collapse when at 40?50%, 50?60% or even 60?70% Bu . More interestingly, for many respondents a population does not recover until at 70?80%, 80?90% or even 100% Bu . These definitions of population collapse and recovery are much more conservative, suggesting very different management objectives for these shark experts or may be a misinterpretation of the concepts applied in natural resource management.

Most respondents agreed that sharks as a group can be fished sustainably but also agreed that only the highly productive species can be fished sustainably. This is a contradiction. When the elements are in place, sharks, as any other natural resource, can be fished sustainably [5] and there are examples of this for species with high [5] and low [6] productivity. Most respondents with a fisheries background adequately addressed the sustainability statements whereas most respondents from other fields gave contradictory responses. This contradiction suggests a lack of understanding of these two questions or confusion about sustainability concepts.

This study must be interpreted within its limitations. As the data collected through the questionnaire lack of a geographical component, it cannot be ruled out that differences in perceptions could be due to differences in the spatial-scale and geographical location of the respondents’ research area or the species they work on. For example, theoretical scientists working on metaanalysis could have different perceptions than field biologists working at local scales. Also scientists working with large iconic shark species could be more conservation-driven than those working with smaller, more productive species. Finally, the term ‘shark’ was intended to be used in a general sense to imply sharks and rays. However, question #12 specifically asked about the sustainability and status of sharks and rays which might have confused some of the respondents

 Public perceptions of marine resource health are often based on controversial information published in high-profile journals that gained disproportionately higher media attention than the rebuttals to these articles [12]. As this information filters through all levels of society, generalisations are made and sharks are no exception. For example, studies reporting large population declines, such as [13-15] have been published in high profile journals and have received considerably more citations (2646, 1025, and 409 respectively; Google Scholar, 10 June 2016), than studies evidencing the exaggerated conclusions drawn by those studies [16], 146 citations; [17], 253 citations) which have been published in fishery journals. Although science-based management of natural resources requires knowledge exchange between scientists, decision makers and other stake holders, information flow can be inhibited by a range of barriers [18]. In fishery sciences in general, there seems to be a communication gap between fishery scientists and society in general, evidencing the need for a better interaction between fishery scientists and the wider public [12]. In terms of the exploitation and population status of sharks, the pattern in the questionnaire responses supports the claims of [12]. I argue that the generalized perception portrayed by the media, focused more on shark collapses, would disproportionately influence shark experts without a fishery background. Most likely, these scientists would not regularly use technical fishery scientific journals as their primarily source of literature. Hence, shark experts without a fisheries background would be less aware of the limitations of the studies reporting global shark collapses, being more prone to citing only these studies for justifying the importance of their own research. This situation may create a communication gap between shark fishery scientists, other scientists and the general public. Further research is required to test the communication-gap hypothesis. For example, a revision of the shark literature would allow understanding the context within which papers on global shark collapses are cited. If there is an actual communication gap, bridging this gap will better inform the public debate and allow improved decision-making

 I would like to thank all conference delegates who took the time to answer the questionnaire. I would also like to thank Steve Taylor, Gary Jackson, Tim Nicholas and two anonymous referees for providing invaluable feedback on an earlier version of the MS

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