scholarly journals Cetacean–fishery interactions in Galicia (NW Spain): results and management implications of a face-to-face interview survey of local fishers

2013 ◽  
Vol 71 (3) ◽  
pp. 604-617 ◽  
Author(s):  
Sabine Goetz ◽  
Fiona L. Read ◽  
M. Begoña Santos ◽  
C. Pita ◽  
Graham J. Pierce
Keyword(s):  
Bottlenose Dolphins ◽  
Management Strategies ◽  
Economic Loss ◽  
Fishing Effort ◽  
Purse Seine ◽  
Fishing Gear ◽  
Nw Spain ◽  
Face To Face ◽  
Fishery Interactions ◽  
Common Dolphins

Abstract Galicia (NW Spain) is an important fishing region with a high potential for cetacean–fishery interactions. Cetacean depredation on catch and damage to fishing gear can potentially lead to substantial economic loss for fishers, while cetacean bycatch raises conservation concerns. With the aim of gathering information on the types and scale of interactions and of suggesting possible management strategies, we conducted face-to-face interviews with fishers in local fishing harbours, in particular to identify specific problematic interactions and to quantify the level of economic loss and bycatch rates associated with these interactions. We found that cetacean–fishery interactions are frequent, although damage to catch and fishing gear by cetaceans was mostly reported as small. Nevertheless, substantial economic loss can result from common bottlenose dolphins (Tursiops truncatus) damaging coastal gillnets and from short-beaked common dolphins (Delphinus delphis) scattering fish in purse-seine fisheries. Cetacean bycatch mortality was reported to be highest for trawls and set gillnets, and probably exceeds sustainable levels for local common and bottlenose dolphin populations. Although interview data may be biased due to the perceptions of interviewees, and therefore should be interpreted with care, the methodology allowed us to cover multiple sites and fisheries within a reasonable time frame. Minimizing cetacean–fishery interactions requires the implementation of case-specific management strategies with the active participation of fishers. For set gillnet and purse-seine fisheries, the use of acoustic deterrent devices (pingers) may prevent cetaceans from approaching and getting trapped in the nets. For trawl fisheries, where bycatch appears to be particularly high at night in water depths of 100–300 m, possible solutions include the implementation of time/area closures and the relocation of some fishing effort to deeper waters.

Behavioural changes and potential consequences of cetacean exposure to purse seine vessels in the Istanbul Strait, Turkey

2020 ◽  
Vol 100 (5) ◽  
pp. 847-856
Author(s):  
Cristóbal Olaya Meza ◽  
Aylin Akkaya ◽  
Flavio Affinito ◽  
Bayram Öztürk ◽  
Ayaka Amaha Öztürk
Keyword(s):  
Bottlenose Dolphins ◽  
Purse Seine ◽  
Traffic Density ◽  
Long Term Effects ◽  
Cetacean Species ◽  
Behavioural Changes ◽  
Fishing Vessels ◽  
Marine Traffic ◽  
Common Dolphins

AbstractMarine traffic has both short- and long-term effects on cetacean behaviour, yet fishing vessels present a unique situation as they disturb cetaceans whilst potentially offering alternative foraging opportunities. The Istanbul Strait is a key area for the study of anthropogenic disturbance on cetaceans due to heavy human pressure in a narrow space where at least three cetacean species are regularly encountered. The present study investigated changes in behaviour of bottlenose dolphins, common dolphins and harbour porpoises in relation to the presence of purse seiners using Markov chains analysis. The results revealed increased foraging in bottlenose and common dolphins' behavioural budgets and a decrease in the time spent foraging by harbour porpoises. Moreover, a loglinear model was used to analyse the effect of possible confounding variables on observed behaviours. The only variables found to be affecting behaviour were the previous recorded behaviour, seiner presence and marine traffic density. Consequently, the presence of purse seine vessels leads bottlenose and common dolphins to change their behaviour and are related with a decrease of energy intake in porpoises. The results of this study reveal that there is an effect of purse seine vessel presence on the cetaceans found in the Istanbul Strait with potentially significant impacts on their behaviour, therefore we suggest more research is needed in the area to identify the long-term impacts of these observed behavioural changes.

scholarly journals The status and trends of small cetacean landings at Dixcove artisanal fishing port, western Ghana

2019 ◽  
Author(s):  
Patrick K Ofori-Danson ◽  
Joseph Debrah ◽  
Koen Van Waerebeek
Keyword(s):  
Coastal Waters ◽  
Bottlenose Dolphins ◽  
Fishing Effort ◽  
Humpback Whales ◽  
Small Scale ◽  
Catch Per Unit Effort ◽  
Western Africa ◽  
Republic Of Benin ◽  
Lagenodelphis Hosei ◽  
Common Dolphins

One of the largest documented takes of small cetaceans in western Africa occurs in Western regional coastal waters of Ghana. This temporally coincided with steadily decreasing catches of finfish, especially small pelagics (sardinellas, anchovies, mackerel) over the past decades, attributed to both climate change and indiscriminate exploitation methods. Dixcove, a key fishing port for cetacean landings was surveyed during 96 days between 12 September -17 December 2018. Our goal was to update insights from our earlier surveys, especially on catch rates, catch per unit effort and species composition. A total of 57 delphinids of 10 species were observed landed: Stenella attenuata (28.1%), Stenella clymene (17.5%), Lagenodelphis hosei (10.5%), Steno bredanensis (10.5%), unidentified stenellids (8.8%), Grampus griseus (3.5%), Delphinus sp. (3.5%), Pseudorca crassidens (3.5%) and single specimens of Tursiops truncatus, Stenella longirostris and Stenella frontalis. The observed cetacean catch per diem (cpd =0.59) at Dixcove was low compared to earlier rates for this port (e.g. cpd =2.82, in 2013-2014). However, fishing effort, measured as the number of canoes landing per diem (range 0-25; mean= 8.82 ± 6.05; n=22) was also reduced. Poor fish catches forced many canoes to remain in port. The prevalence in landings of common bottlenose dolphins and common dolphins has significantly decreased in the period 2000-2018. The prevalence of Fraser's dolphins and false killer whales increased. Indications are that a higher proportion of cetacean carcasses may be utilised offshore as shark bait. Hooks baited with cetacean parts are deployed in auxiliary longlines set longside large-mesh drift gillnets with a shark aggregating purpose, a first report in Africa. Shore-based incidental sightings of humpback whales suggest the potential for small scale whale-watching ecotourism in Ghanaian coastal waters, as pertains in the nearby waters of the Republic of Benin.

scholarly journals Analisis Kapasitas Perikanan dengan Pendekatan Data Envelopment Analysis (DEA) di Perairan Utara Gorontalo

2009 ◽  
Vol 10 (1) ◽  
pp. 23-33
Author(s):  
Abdul Hafidz Olii
Keyword(s):  
Data Envelopment Analysis ◽  
Fishing Effort ◽  
Purse Seine ◽  
Fish Stock ◽  
Fishing Gear ◽  
Data Envelopment ◽  
Fishing Boat ◽  
Gill Net ◽  
Fishing Capacity ◽  
Using Data

Fishing capacity is ability of fishery input (boat) used in output production (catch), it measured by using fishing unit or other fishing gear production. In simple way, fishing capacity is an ability of fishing boat (with all aspects) to capture fish. This ability will depend on the fish stock to be captured (seasonally or yearly) and the ability of the fishing gear itself. The aims of this research are to analyze technical efficiency and capacity of capture fishery in between years, of fishing gear and of purse seine. Research location was in the northern water of Gorontalo. Data was analyzed using data envelopment analysis (DEA). The development of capture fishery in 20 years since 1986 - 2005 of the northern water of Gorontalo showed that 1995, 2003 and 2005 are the most efficient years compared to other years, therefore, these years can be used as a basic of allocating fishing effort and catch. The most efficient fishing gear was purse seine and line, whereas gill net is an inefficient fishing gear. For purse seine, there are 11 boats that have efficiency value of 1. In order to reach efficiency level of each purse seine, it needs to decrease the number of input such as reducing 27.97 percent of boat, reducing the length of fishing duration to 29.49 percent,reducing the length of fishing trip / tonnage month to 26.87 percent and reducing fishing operation cost to 15.67 percent.

scholarly journals The status and trends of small cetacean landings at Dixcove artisanal fishing port, western Ghana

2019 ◽  
Author(s):  
Patrick K Ofori-Danson ◽  
Joseph Debrah ◽  
Koen Van Waerebeek
Keyword(s):  
Coastal Waters ◽  
Bottlenose Dolphins ◽  
Fishing Effort ◽  
Humpback Whales ◽  
Small Scale ◽  
Catch Per Unit Effort ◽  
Western Africa ◽  
Republic Of Benin ◽  
Lagenodelphis Hosei ◽  
Common Dolphins

One of the largest documented takes of small cetaceans in western Africa occurs in Western regional coastal waters of Ghana. This temporally coincided with steadily decreasing catches of finfish, especially small pelagics (sardinellas, anchovies, mackerel) over the past decades, attributed to both climate change and indiscriminate exploitation methods. Dixcove, a key fishing port for cetacean landings was surveyed during 96 days between 12 September -17 December 2018. Our goal was to update insights from our earlier surveys, especially on catch rates, catch per unit effort and species composition. A total of 57 delphinids of 10 species were observed landed: Stenella attenuata (28.1%), Stenella clymene (17.5%), Lagenodelphis hosei (10.5%), Steno bredanensis (10.5%), unidentified stenellids (8.8%), Grampus griseus (3.5%), Delphinus sp. (3.5%), Pseudorca crassidens (3.5%) and single specimens of Tursiops truncatus, Stenella longirostris and Stenella frontalis. The observed cetacean catch per diem (cpd =0.59) at Dixcove was low compared to earlier rates for this port (e.g. cpd =2.82, in 2013-2014). However, fishing effort, measured as the number of canoes landing per diem (range 0-25; mean= 8.82 ± 6.05; n=22) was also reduced. Poor fish catches forced many canoes to remain in port. The prevalence in landings of common bottlenose dolphins and common dolphins has significantly decreased in the period 2000-2018. The prevalence of Fraser's dolphins and false killer whales increased. Indications are that a higher proportion of cetacean carcasses may be utilised offshore as shark bait. Hooks baited with cetacean parts are deployed in auxiliary longlines set longside large-mesh drift gillnets with a shark aggregating purpose, a first report in Africa. Shore-based incidental sightings of humpback whales suggest the potential for small scale whale-watching ecotourism in Ghanaian coastal waters, as pertains in the nearby waters of the Republic of Benin.

scholarly journals Determinants of lungworm specificity in five cetacean species in the western Mediterranean

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Rachel Pool ◽  
Clara Romero-Rubira ◽  
Juan Antonio Raga ◽  
Mercedes Fernández ◽  
Francisco Javier Aznar
Keyword(s):  
Bottlenose Dolphins ◽  
Parasite Burden ◽  
Western Mediterranean ◽  
Host Size ◽  
Cetacean Species ◽  
Stenella Coeruleoalba ◽  
Species Similarity ◽  
Pilot Whales ◽  
Common Dolphins ◽  
Prey Overlap

Abstract Background Current data about Pseudaliidae show contrasting patterns of host specificity between congeneric species. We investigated how both contact and compatibility between hosts and parasites contributed to the patterns of lungworm infection observed in a community of five species of cetaceans in the western Mediterranean. Methods The lungs of 119 striped dolphins Stenella coeruleoalba, 18 bottlenose dolphins Tursiops truncatus, 7 Risso’s dolphins Grampus griseus, 7 long-finned pilot whales Globicephala melas, and 6 common dolphins Delphinus delphis were analysed for lungworms. Parasites were identified by morphology and analysis of ITS2 sequences using both maximum likelihood and Bayesian inference methods. Body length was used as a proxy for lungworm species fitness in different hosts and compared with Kruskal-Wallis tests. Infection parameters were compared between cetacean species using Fisher’s exact tests and Kruskal-Wallis tests. Phylogenetic specificity was explored by collating the overall lungworm species prevalence values in hosts from previous surveys in various localities. To explore the relative importance of vertical and horizontal transmission, Spearman’s rank correlation was used to look for an association between host size and lungworm burden. A Mantel test was used to explore the association between lungworm species similarity and prey overlap using dietary data. Results Halocercus delphini had higher infection levels in striped dolphins and common dolphins; Stenurus ovatus had higher infection levels in bottlenose dolphins; and Stenurus globicephalae had higher infection levels in long-finned pilot whales. These results are congruent with findings on a global scale. Morphometric comparison showed that the larger nematodes were found in the same host species that had the highest parasite burden. Lungworms were found in neonatal striped dolphins and a Risso’s dolphin, and there was a weak but significant correlation between host size and parasite burden in striped dolphins and bottlenose dolphins. There was also a weak but significant association between prey overlap and lungworm species similarity. Conclusions Data indicate that phylogenetic specificity has an important role in governing host–parasite associations, as indicated by the higher infection levels and larger nematode size in certain hosts. However, diet can also influence infection patterns in these preferred hosts and contribute to less severe infections in other hosts.

Preliminary observations on abundance and distribution of fish fauna in a canyon of the Bay of Biscay (ICES Division 8c)

2021 ◽  
pp. 1-10
Author(s):  
G. Diez ◽  
L. Arregi ◽  
M. Basterretxea ◽  
E. Cuende ◽  
I. Oyarzabal
Keyword(s):  
Deep Sea ◽  
Basque Country ◽  
Fish Fauna ◽  
Fishing Effort ◽  
Fishing Gear ◽  
Clear Trend ◽  
Depth Ranges ◽  
Abundance And Distribution ◽  
Sea Fish ◽  
Distribution Of Fish

Abstract The changes in abundance and biodiversity of deep-sea fish fauna are described based on an annual deep-water longline survey with data collected during the period 2015–2019 in the Basque Country continental Slope (ICES Division 8c). The sampling scheme included hauls in four 400 m strata, from 650–2250 m deep. The DST sensors installed in the main line have allowed us to set an accurate soak time for each haul, and they were used to calculate fishing effort and CPUE by haul. The catchability of the fishing gear indicated that 15% of the total hooks deployed in the five-year period were able to fish, and that the bottom longline was very effective in fishing a wide number of different species in all depth ranges. The fishing gear caught 14 different species of sharks (13 deepwater and one pelagic), two chimaeras and nine teleosts. The abundance and biomass registered on the hooks attached to the bottom were between three and four times higher than in the floating sections, and the highest CPUE and biomass were recorded between 1051–1450 m, from 2015 to 2017, and in the 1451–1850 m strata, but they do not show any clear trend throughout the five years of the series.

Fatigue-management strategies among women with endometriosis in South Africa: a qualitative study

2021 ◽  
pp. 008124632110201
Author(s):  
Zamafiso Nombulelo Sibande ◽  
Rizwana Roomaney
Keyword(s):  
South Africa ◽  
South African ◽  
Psychosocial Intervention ◽  
Public Hospital ◽  
Management Strategies ◽  
Cognitive Strategies ◽  
Secondary Symptom ◽  
Face To Face ◽  
Fatigue Management ◽  
Insight Into

Fatigue is a common, secondary symptom of endometriosis that has not been qualitatively explored. We conducted individual, face-to-face interviews with 25 women in South Africa about their experiences of endometriosis-related fatigue. Participants were recruited at a public hospital in Cape Town and through several South African endometriosis organizations. Interviews were conducted in English and Afrikaans and ranged from 30 min to 1 hr 16 min in duration. All interviews were audio recorded and transcribed. Interviews were analyzed using thematic analysis. We found that both the experience of fatigue and fatigue-management strategies were highly personalized. Participants reported using a variety of cognitive strategies, such as planning, pacing, and pushing through their fatigue to reduce the levels of fatigue. Participants also employed physical strategies such as rest, dietary changes, using supplements, and exercise. We found that while participants often tried fatigue-management strategies suggested to them by others, they struggled to maintain these strategies even when they were successful. There are currently no interventions aimed at reducing endometriosis-related fatigue. The findings of this study provide insight into the management of fatigue in women with endometriosis and may be used to develop a psychosocial intervention for fatigue among women with the disease.

scholarly journals ANALISIS ASPEK TEKNIS KAPAL PUKAT CINCIN (PURSE SEINE) DAN ALAT TANGKAP YANG DIGUNAKAN NELAYAN DI PERAIRAN TELUK BONE

2020 ◽  
Vol 3 (2) ◽  
pp. 226-238
Author(s):  
Hawati Hawati ◽  
Angkasa Putra
Keyword(s):  
Survey Methods ◽  
Secondary Data ◽  
Purse Seine ◽  
Primary Data ◽  
Fishing Gear ◽  
Technical Aspects ◽  
Fish Resources ◽  
Trawl Fishing ◽  
Fisheries Regulation ◽  
Fishing Area

The utilization of fish resources by fishermen in the waters of Bone Bay uses different fishing gear and patterns as well as different utilization and management policies. This can affect the sustainability of existing fish resources, one of which is in the Bone Regency area. This study aims to analyze the technical aspects of purse seine and fishing gear used by fishermen in the waters of Bone Bay, especially in Bone Regency. Furthermore, the technical aspects of the vessel and fishing gear as a result of the calculation are compared with the provisions stipulated in the PERMEN-KP Number 71 of 2016 to determine the zone of the fishing area. This research was conducted in Panyula Village, which is the fishing base area of purse seine fishermen and the waters of Teluk Bone, starting from November 2016 to March 2017. This research uses a combination of survey methods and case studies. The type of data used consists of primary data and secondary data. Based on the technical aspects of purse seine vessels, ring trawl fishing gear and FAD fishing tools, purse seine units should be operated on Fishing Route II and Fishing Route III in accordance with Minister of Marine Affairs and Fisheries Regulation Number 71 of 2016.

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