Temporal patterns of target catch and sea turtle bycatch in the US Atlantic pelagic longline fishing fleet

2010 ◽  
Vol 67 (1) ◽  
pp. 42-57 ◽  
Author(s):  
Connie Y. Kot ◽  
Andre M. Boustany ◽  
Patrick N. Halpin
Keyword(s):  
Temporal Patterns ◽  
Sea Turtle ◽  
Fishing Effort ◽  
Dermochelys Coriacea ◽  
Fishing Gear ◽  
Thunnus Albacares ◽  
Moon Phase ◽  
The Us ◽  
Management And Conservation ◽  
Pelagic Longline

Sea turtle bycatch in pelagic longline fishing gear is an ongoing threat to the conservation of sea turtle populations. However, these bycatch events do not occur uniformly in space or time. Leatherback ( Dermochelys coriacea ) and loggerhead ( Caretta caretta ) bycatch rates reported in large fishing regions exhibited different degrees of interannual variability. Target catch and sea turtle bycatch in most regions displayed strong periodicity that corresponded to seasons (~365 days) and/or moon phase (~29 days). When trends in catch and bycatch rates were examined by month and moon phase, the significant periods of higher and lower catch and bycatch related to swordfish ( Xiphias gladius ), yellowfin tuna ( Thunnus albacares ), and sea turtle temporal distributions in foraging and spawning/nesting, oceanographic and prey conditions, and foraging behavior. Catch and bycatch rates tended to depend more on a seasonal rather than a lunar time scale, although there is likely an interaction between the two. These findings provide insights to the susceptibility of target catch and bycatch, regional and temporal patterns of fishing effort, and potential guidance for resource management and conservation.

scholarly journals Methods to Reduce Sea Turtle Interactions in the Atlantic Canadian Pelagic Long Line Fleet

2017 ◽  
Author(s):  
Zachary T. Sherker
Keyword(s):  
Sea Turtles ◽  
The United States ◽  
Sea Turtle ◽  
Fishing Effort ◽  
Dermochelys Coriacea ◽  
Small Scale ◽  
The North ◽  
Spatio Temporal ◽  
Socio Economic Impact ◽  
By Catch

AbstractThis project investigates the role of fisheries management in the conservation of loggerhead (Caretta caretta) and leatherback sea turtles (Dermochelys coriacea), both of which are currently listed as vulnerable by the IUCN (International Union for Conservation of Nature). These species migrate from nesting grounds in South America to feed on gelatinous zooplankton (jellyfish) in the North Atlantic off the coast of the United States and Canada. The seasonal foraging grounds of sea turtles heavily overlap with areas of high fishing effort for the longline tuna and swordfish fleet, a fishery that has significantly high rates of sea turtle incidents. The dynamic nature of sea turtle foraging patterns renders static spatio-temporal fishing area closures ineffective. Rather, turtle by-catch mitigation requires small-scale, event-triggered closures and decentralized management to reduce incidents while minimizing the negative socio-economic impact of area closures on fishermen. A number of methods that increase fishing selectivity have been implemented in other commercial fisheries around the globe and are suggested for the Atlantic Canadian fleet moving forward.

scholarly journals Fishery biology of the swordfish (Xiphias gladius, Linnaeus 1758) caught by surface longliners based in Itajaí, southern Brazil

2011 ◽  
Vol 59 (2) ◽  
pp. 171-184 ◽  
Author(s):  
Ana Lia Campos Quaggio ◽  
Rosângela P. T. Lessa ◽  
Jorge Eduardo Kotas ◽  
Celson F. Lin
Keyword(s):  
Sea Turtle ◽  
Fishing Effort ◽  
Commercial Fishing ◽  
Lunar Phase ◽  
Southern Brazil ◽  
Southwest Atlantic ◽  
Fishery Biology ◽  
Covariance Models ◽  
Xiphias Gladius ◽  
Pelagic Longline

The Xiphias gladius (Linnaeus, 1758) data used in the present study were obtained from commercial fishing cruises of the pelagic longline fleet based in Itajaí, operating in the Southwest Atlantic. For the Covariance models, fishing effort (number of hooks) and catches (kg) were pooled and categorized into the following groups: (1) year (1997, 1998, 2001, 2002 and 2007); (2) lunar phase; and (3) seasons, fishing effort being the covariate. The highest mean swordfish catch (kg) occurred during the waxing crescent moon and during wintertime. The Mantel-Haenszel procedure was applied to compare the efficiency of the two hooks tested, and showed that the "J" hook type (J 9/0 10º offset), traditionally used by the fleet, catches 1.2-fold more Xiphias gladius than the circle hook (18/0 10º offset), used as an optional device to reduce sea turtle bycatch. The conversion of individual dressed weight (kg) into total length (cm) from 2000 to 2002, showed that sub-adults represented 66% of the total catch.

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.

scholarly journals Long-term decline of the western Pacific leatherback,Dermochelys coriacea: a globally important sea turtle population

Ecosphere ◽  
2013 ◽  
Vol 4 (2) ◽  
pp. art25 ◽  
Author(s):  
Ricardo F. Tapilatu ◽  
Peter H. Dutton ◽  
Manjula Tiwari ◽  
Thane Wibbels ◽  
Hadi V. Ferdinandus ◽  
...  
Keyword(s):  
Sea Turtle ◽  
Western Pacific ◽  
Dermochelys Coriacea ◽  
Turtle Population ◽  
The Western Pacific

scholarly journals Reproductive biology of Haemulon plumieri (Teleostei: Haemulidae) in Ceará state, Northeastern Brazil

2013 ◽  
Vol 73 (2) ◽  
pp. 391-396 ◽  
Author(s):  
RA Shinozaki-Mendes ◽  
J Santander-Neto ◽  
JRF Silva ◽  
FHV Hazin
Keyword(s):  
Reproductive Biology ◽  
Fishing Effort ◽  
Northeastern Brazil ◽  
Tropical Species ◽  
Stock Management ◽  
Western Atlantic ◽  
Total Fecundity ◽  
Maturation Stages ◽  
First Maturity ◽  
Management And Conservation

The Haemulon plumieri is a typical reef-associated and tropical species found in warm and temperate waters of the Western Atlantic. Due to the large fishing effort directed to H. plumieri, the knowledge about its reproductive biology is essential for correct stock management and conservation. The aim of this study was to characterise reproductive biology with a focus on its seasonal variation of gonadal maturation stages, first maturation size and fecundity. Specimens were monthly collected and a total of 119 females and 136 males were analysed. The reproductive cycle of Haemulon plumieri is seasonal, with higher activity between March and May. Size at first maturity (L50) was estimated at 16.86 and 18.55 cm for females and males, respectively. The total fecundity ranged between 17,816 and 120,333 mature oocytes per female and relative fecundity was 235 ± 63 oocyte.g−1 whereas batch fecundity varied between 20 and 25% from total fecundity. Since the species is widely caught, we suggest a closed season from March to May and to establish a minimum catch size of 18.5 cm for both sexes, since there is no evident sexual dimorphism.

scholarly journals Estimating clutch frequency in the sea turtle Dermochelys coriacea using stopover duration

2006 ◽  
Vol 317 ◽  
pp. 285-295 ◽  
Author(s):  
P Rivalan ◽  
R Pradel ◽  
R Choquet ◽  
M Girondot ◽  
AC Prévot-Julliard
Keyword(s):  
Sea Turtle ◽  
Dermochelys Coriacea ◽  
Stopover Duration

Abstract 60: National Temporal Patterns in Recurrent Stroke by Demographic Characteristics and Geographic Regions: 2001-2016

Stroke ◽  
2021 ◽  
Vol 52 (Suppl_1) ◽  
Author(s):  
Judith H Lichtman ◽  
Erica C Leifheit ◽  
Yun Wang ◽  
Larry B Goldstein
Keyword(s):  
Proportional Hazards Model ◽  
Recurrent Stroke ◽  
Temporal Trends ◽  
Healthcare Delivery ◽  
Temporal Patterns ◽  
Cox Proportional Hazards ◽  
Cox Proportional Hazards Model ◽  
Fee For Service ◽  
The Us ◽  
Over Time

Background: There have been important advances in secondary stroke prevention and a focus on healthcare delivery in the US over the past two decades. Yet, little is known about temporal patterns of recurrent stroke in the US. We examined temporal trends in recurrent stroke by sociodemographic characteristics and geographic areas using national Medicare data. Methods: We included fee-for-service Medicare beneficiaries aged ≥65y with a primary discharge diagnosis of ischemic stroke from 2001 to 2016. We fit a Cox proportional hazards model that censored for change in Medicare enrollment and accounted for death to evaluate the temporal trend in 1-year recurrent stroke, adjusting for demographic and clinical factors. Models were repeated for subgroups defined by age, sex, race, and state. We mapped smoothed rates of 1-year recurrent stroke by county to assess geographic variation over time. Results: There were 3,485,618 unique beneficiaries discharged with stroke during the study period. Demographic and clinical characteristics remained relatively stable over time, but the proportions discharged with home health services and inpatient rehabilitation increased. The observed 1-year recurrent stroke rate decreased from 11.2% in 2001-2004 to 9.3% in 2013-2016, with an adjusted annual reduction in recurrence from 2001-2016 of 1.49% (95% CI 1.40%-1.58%). There were significant reductions for all age, sex, and race groups (A). Geographic areas with persistently high rates were identified over time (B). In state-stratified analysis, the annual percentage reduction in recurrence ranged from -1.2% to 2.5% and was significant for all but 12 states. Conclusions: Recurrent strokes decreased over time overall and by sociodemographic subgroups; however, we identified geographic areas with persistently high recurrence rates. Such findings can target secondary prevention intervention opportunities for high-risk populations and communities.

Incidental capture of elasmobranchs in the bottom-set gill-net fishery off the south coast of Ireland

1994 ◽  
Vol 74 (4) ◽  
pp. 837-847 ◽  
Author(s):  
S.D. Berrow
Keyword(s):  
Fishing Effort ◽  
South Coast ◽  
Fishing Gear ◽  
The South ◽  
Blue Shark ◽  
Incidental Capture ◽  
Gill Net ◽  
Total Capture ◽  
Catch Rates ◽  
Basking Shark

The incidental capture of sharks in the bottom-set gill-net fishery off the south coast of Ireland was quantified by placing observers on commercial gill-netters for the duration of a fishing trip. Forty fishing trips were sampled resulting in 1,167 km and 19,760 km h of observed fishing effort. Sixty individual sharks of seven species were reported entangled in the fishing gear. Tope, porbeagle and six-gilled sharks were the most frequently caught species, with black-mouthed dogfish, blue shark, basking shark and starry smooth hound also recorded. Total fishing effort along the south coast was calculated and total capture extrapolated from observed catch rates. An estimated 6,000 sharks were caught in this fishery during the study period.

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