Sawfish exploitation and status in Bangladesh

Abstract

Sawfish are among the world's most threatened and understudied marine fishes. There are few studies on sawfish from outside Australian and USA waters ‐ a significant knowledge gap considering their circumtropical distribution and migratory nature. This paper presents the first assessment of sawfish exploitation and status in Bangladesh: a country that is subject to extensive fishing efforts, and home to the largest mangrove forest on Earth – an ecosystem that provides critical nursery habitat for juvenile sawfish. A countrywide rapid assessment was undertaken between December 2011 and November 2012, using an interdisciplinary methodology. Fish landing stations, dry fish markets, and fishing villages were visited and a sawfish medicine maker was found and interviewed. In addition, interviews with national specialists at academic and fisheries institutions were undertaken. In total, 203 questionnaire surveys were conducted with fishers and traders in order to understand the extent of decline, potential drivers of declines, and local perceptions and uses of sawfish. Eighteen rostra were documented from museum archives and private collections, and unpublished data were sourced. Two sawfish species, Pristis pristis and Anoxypristis cuspidata were confirmed to be present in Bangladesh. General population declines were revealed. The average annual sawfish encounter rate (observations and catches) declined from 3.7 individuals using lifetime recall data (~22‐year), to 1.5 using 5‐year recall data, and further to 0.7 using 1‐year recall data. The consensus from social research methods was that sawfish were caught as bycatch, with drift gill nets being cited as the most damaging gear type. Every respondent perceived sawfish as a useful animal – typically for medicinal or cultural values. Conservation measures are proposed, including a local education and outreach programme to seek behavioural changes – primarily to release live sawfish. Copyright © 2014 John Wiley & Sons, Ltd.

Fishers’ ecological knowledge of sawfishes in the Sepik and Ramu rivers, northern Papua New Guinea

“…We focused on interview surveys because they are a rapid means of assessing the historical and current presence of sawfishes in datapoor regions and are a cost-and time-effective means of collecting data on the occurrence of easily recognisable species such as sawfishes in landings (e.g. Poulakis & Seitz 2004, Hossain et al 2015, Jabado et al 2017 this Theme Section, Leeney 2017).…”

Is this the last stand of the Critically Endangered green sawfish Pristis zijsron in the Arabian Gulf?

“…Our sample size was lower than that in other studies using TEK to understand sawfishes (e.g. Hossain et al 2015, Leeney & Downing 2016). Yet, the consistency and high proportion of respondents recounting similar stories, uses, and locations lend credibility to the value of the information collected in this study.…”

“…Our results underscore the importance of using TEK as a tool to gather information on under-studied and threatened species and confirm that sawfish populations persist along the coast of the UAE. The use of TEK to document occurrence trends in sawfish has recently increased and has em phasized the disappearance of these species from various countries (Robillard & Séret 2006, Giglio et al 2015, Hossain et al 2015, Leeney 2016, Reis-Filho et al 2016 Several studies have pointed to the fact that, in areas where sawfishes used to abound, many fishers are no longer able to immediately recognize pictures of sawfish or have never seen one (Robillard & Séret 2006, Giglio et al 2015, Leeney & Poncelet 2015, Leeney 2016, Leeney & Downing 2016, Reis-Filho et al 2016. All fishers approached in the UAE were able to recognize the sawfish illustration presented, with a number of them stating they had seen a sawfish in the few months prior to the interviews.…”

“…This method is being increasingly used to gain a better understanding of sawfish in data-poor areas as well as to inform science and management (Robillard & Séret 2006, Norton et al 2012, Hossain et al 2015, Leeney 2015, Leeney & Poncelet 2015, Dulvy et al 2016, Reis-Filho et al 2016. For example, data collected from sawfish encounters in the USA have provided baseline information for the identification of critical habitats and nursery hotspots, as well as seasonal movements (Seitz & Poulakis 2002, Poulakis & Seitz 2004, Norton et al 2012.…”

Smalltooth sawfish (Pristis pectinata Latham, 1794) in the Casamance River, Senegal: A historical perspective

“…The increasing alarm over the global demise of sawfishes (family Pristidae) throughout much of their former range has led to considerable research focus on this group in recent years, both to better understand the historical range of the taxon (Dulvy et al, ) and to generate up‐to‐date baseline data to focus future conservation efforts (e.g. Hossain et al, ; Leeney & Downing, ; Leeney & Poncelet, ). Such studies on the occurrence and distribution of sawfishes at a regional level are necessary to determine the extent of remaining populations.…”