Reducing green turtle bycatch in small-scale fisheries using illuminated gillnets: the cost of saving a sea turtle

The bycatch of sea turtles by industrial fisheries is receiving an increasing attention in recent years due to the high impact it causes on these endangered species. This issue was evaluated in southern Spain waters that harbors an important feeding ground of loggerhead and leatherback turtles, including the endangered Eastern Atlantic loggerhead population. To quantify the impact that different fisheries represents to sea turtles, 272 fishermen answered to detailed illustrated questionnaires in all the main ports of Andalusia and Murcia (Spain) during 2014. This study has updated the knowledge of turtle bycatch in the southwestern Mediterranean revealing a widespread impact of fisheries on sea turtles. Fishermen recognized an annual catch of 2.3 turtles per boat. Considering the census of industrial fishing boats in the study area (1182), more than 2840 sea turtles could be bycaught per year in the study area. Most of captures (96.2%) were produced during the summer. These results suggest a severe impact of most of legal fisheries (surface longline, pursue seine, trawling and small scale fisheries) on loggerhead feeding grounds in the southwestern Mediterranean. Fishermen suggests that drift fishing conducted by foreign or illegal fishermen and almadrabas are also causing a significant bycatch of turtles. Several measures such as reviewing compliance of current fishing and environmental regulations, modifying turtle technics to reduce turtle bycatch, facilitating the rescue and handle of wound turtles and their transport to the port for recovery, and recognizing the efforts of anglers to perform a more sustainable fishing, are recommended to mitigate this impact.

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Trading information for conservation: a novel use of radio broadcasting to reduce sea turtle bycatch

Oryx ◽

10.1017/s0030605312000105 ◽

2012 ◽

Vol 46 (3) ◽

pp. 332-339 ◽

Cited By ~ 16

Author(s):

Joanna Alfaro-Shigueto ◽

Jeffrey C. Mangel ◽

Peter H. Dutton ◽

Jeffrey A. Seminoff ◽

Brendan J. Godley

Keyword(s):

Marine Mammals ◽

Low Cost ◽

Sea Turtle ◽

Small Scale ◽

Marine Biodiversity ◽

Radio Communication ◽

Marine Turtles ◽

Small Scale Fisheries ◽

Novel Approach ◽

Spatial Coverage

AbstractBycatch of non-target animals in small-scale fisheries poses a major threat to seabirds and marine mammals and turtles. This is also a problem for small-scale fisheries in Peru because of the magnitude of these fisheries and the important marine biodiversity in Peruvian waters. Here we describe how we implemented a novel approach to mitigate bycatch impacts on marine turtles in Peru. We used high-frequency (HF) two-way radio communication to exchange information with fishers. We sought data that would afford insights into fishing patterns and levels of turtle bycatch so that we could identify areas of high-density bycatch in real time and warn other fishers. In return we provided oceanographic and atmospheric information useful for the fishers. Radio communication also served as a platform to promote the use of safe handling and release techniques for incidentally caught animals. During the 24 months of the programme we communicated with over 200 vessels and with 200–1,400 fishers, who used primarily longlines, gillnets, jiggers, purse seiners and trawlers. Our findings suggest that HF radio communication is a useful tool (low cost and widely used by fishers, with extensive spatial coverage), helps build links with fishers that potentially reduces fishery impacts on marine turtles, and can also provide information on poorly documented fisheries and the relevant bycatch data associated with small-scale fishing practices.

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Structural description of sea turtle fibropapilloma

Brazilian Journal of Veterinary Pathology ◽

10.24070/bjvp.1983-0246.v13i3p585-591 ◽

2020 ◽

Vol 13 (3) ◽

pp. 585-591

Author(s):

Luana Melo ◽

Isabel Velasco ◽

Julia Aquino ◽

Rosangela Rodrigues ◽

Edris Lopes ◽

...

Keyword(s):

Green Turtle ◽

Chelonia Mydas ◽

Sea Turtle ◽

Tumor Formation ◽

Neoplastic Disease ◽

Structural Description ◽

Chemical Carcinogens ◽

Epidermal Proliferation ◽

Turtle Population ◽

Bulky Mass

Fibropapillomatosis is a neoplastic disease that affects sea turtles. It is characterized by multiple papillomas, fibropapillomas and cutaneous and/or visceral fibromas. Although its etiology has not been fully elucidated, it is known that there is a strong involvement of an alpha - herpesvirus, but the influence of other factors such as parasites, genetics, chemical carcinogens, contaminants, immunosuppression and ultraviolet radiation may be important in the disease, being pointed out as one of the main causes of a reduction in the green turtle population. Thus, the objective of this article was to describe the morphology of cutaneous fibropapillomas found in specimens of the green turtle (Chelonia mydas), using light and scanning electron microscopy in order to contribute to the mechanism of tumor formation. Microscopically, it presented hyperplastic stromal proliferation and epidermal proliferation with hyperkeratosis. The bulky mass was coated with keratin, with some keratinocyte invaginations, that allowed the keratin to infiltrate from the epidermis into the dermis, forming large keratinized circular spirals. Another fact that we observed was the influence of the inflammation of the tumors caused by ectoparasites.

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The Effect of Invertebrate Infestation on Green Turtle (Chelonia mydas) Nests on Kazanlı Beach, Mersın, Turkey

Russian Journal of Herpetology ◽

10.30906/1026-2296-2020-27-5-245-256 ◽

2020 ◽

Vol 27 (5) ◽

pp. 245-256

Author(s):

Cemil Aymak ◽

Aşkın Hasan Uçar ◽

Yusuf Katılmış ◽

Eyup Başkale ◽

Serap Ergene

Keyword(s):

Green Turtle ◽

Hatching Success ◽

Negative Relationship ◽

Chelonia Mydas ◽

Sea Turtle ◽

Faunal Composition ◽

Independent Variables ◽

Invertebrate Species ◽

First Time ◽

Nesting Season

In this study invertebrate infestation in green turtle (Chelonia mydas) nests were recorded for the first time for Kazanlı beach, Mersin, Turkey. For this aim, in 2006 nesting season, 294 natural intact green turtle nests were sampled to examine their contents and invertebrate infestation was found in 76 (25.85% of the total sampling green turtle nests). These infested nests were examined in terms of the invertebrate faunal composition. The specimens found in the green sea turtle nests were identified to order, family or genus levels and they were represented in 5 orders. These invertebrate groups are Elater sp. larvae (Elateridae; Coleoptera), Pimelia sp. larvae (Tenebrionidae; Coleoptera), Enchytraeidae (Oligochaeta), Cyrptostigmata (Acari), Oniscidae (Isopoda), Formicidae (Hymenoptera). Elater sp. was the most common invertebrate group in the green turtle nests. According to student t test, we found statistically significant differences between 7 independent variables and invertebrate species presence. Furthermore, logistic regression analysis explained that there is a negative relationship between hatching success rate and invertebrate species presence.

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The Mobilization of Small Scale Fisheries Community with Knowledge Management for Conservation and Restoration of the Marine and Coastal Resources in the Gulf of Thailand, Songkhla Province

SSRN Electronic Journal ◽

10.2139/ssrn.3546282 ◽

2019 ◽

Author(s):

Sayan Thongsri ◽

Wannee Niamhom ◽

Sunti Srisuantaeng

Keyword(s):

Knowledge Management ◽

Small Scale ◽

Gulf Of Thailand ◽

Coastal Resources ◽

Small Scale Fisheries ◽

The Gulf Of Thailand

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Dysbaric osteonecrosis associated with decompression sickness in a fishing diver

Undersea and Hyperbaric Medicine ◽

10.22462/04.06.2019.17 ◽

2019 ◽

pp. 217-220

Author(s):

Eduardo Briceño-Souza ◽

◽

Nina Méndez-Domínguez ◽

Ricardo j Cárdenas-Dajda ◽

Walter Chin ◽

...

Keyword(s):

Femoral Head ◽

Decompression Sickness ◽

Small Scale ◽

Prior History ◽

Radiological Findings ◽

Small Scale Fisheries ◽

Left Limb ◽

History Of ◽

Decompression Stress ◽

Probable Diagnosis

Diving as a method of fishing is used worldwide in small-scale fisheries. However, one of the main causes of morbidity and mortality among fishermen is decompression sickness (DCS). We report the case of a 46-year-old male fisherman diver who presented with chronic inguinal pain that radiated to the lower left limb. Living and working in a fishing port in Yucatan, he had a prior history of DCS. A diagnosis of avascular necrosis in the left femoral head secondary to DCS was made via analysis of clinical and radiological findings. The necrosis was surgically resolved by a total hip arthroplasty. Dysbaric osteonecrosis is a more probable diagnosis. In this region fishermen undergo significant decompression stress in their daily fishing efforts. Further studies regarding prevalence of dysbaric osteonecrosis among small-scale fisheries divers are needed. In a community where DCS is endemic and has become an epidemic, as of late, the perception of this health risk remains low. Furthermore, training and decompression technique are lacking among the fishing communities.

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Fisheries Sustainability through Soft Multi-Use Maritime Spatial Planning and Local Development Co-Management: Potentials and Challenges in Greece

Sustainability ◽

10.3390/su12052026 ◽

2020 ◽

Vol 12 (5) ◽

pp. 2026 ◽

Cited By ~ 4

Author(s):

Stella Sofia I. Kyvelou ◽

Dimitrios G. Ierapetritis

Keyword(s):

Spatial Planning ◽

Local Development ◽

Small Scale ◽

Artisanal Fisheries ◽

Sustainable Livelihood ◽

Small Scale Fisheries ◽

Island Communities ◽

The Mediterranean ◽

Family Based ◽

Maritime Spatial Planning

Small-scale fisheries in the Mediterranean represent a significant part of the fisheries industry and their substantial social, economic and place attachment related role has always been acknowledged in the region. Despite the fact that this usually family-based endeavor has a vast economic impact on coastal and island communities of the sea-basin, data and insights on the Mediterranean artisanal fisheries continue to be inadequately developed and poorly integrated in the local development strategies. Thus, the aim of this research is two-fold. Firstly, it presents some data and facts on the fisheries sector in the region and secondly it explores the options of their survival, prosperity and sustainability, approaching the combination of fisheries and tourism as a small-scale and soft “multi-use” in the marine space. Greece, with a huge potential in both the fisheries and the tourism sector, was used as focus area where a co-development process was designed aiming to identify advantages/potentials and challenges/disadvantages of the co-existence of artisanal fisheries and tourism, as perceived by a series of stakeholders including the co-management schemes (Fisheries Local Action Groups, FLAGs) in the country. Key conclusion is that sustainable livelihood from small-scale fisheries depends on the correlation between fisheries and other marine activities. Despite some limitations, this can boost sustainable local development and be a unique pattern of a “win-win” and soft multi-use marine spatial planning (MSP), with economic, environmental, social, cultural and governance related benefits for the coastal communities.

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