Catch, Effort and Socio–Economic Dynamics of Filter Net Fishery In Aparri Cagayan River Estuary - A Preliminary Study

2014 ◽  
Vol 7 (1) ◽  
Author(s):  
LENIMFA P. MOLINA ◽  
WILMA S. URMENETA ◽  
SIMEON R. RABANAL, JR. ◽  
SAMUEL T. AMABA, JR.
Keyword(s):  
Extended Family ◽  
River Estuary ◽  
Elementary Level ◽  
Catch Per Unit Effort ◽  
Economic Dynamics ◽  
Alternative Source ◽  
Moon Phases ◽  
Community Activities ◽  
Preliminary Study ◽  
Catch Rates

This research undertaking was conducted in Aparri, Cagayan, particularlyat the Cagayan River Estuary. The study generally characterized the catch rates and socio–economic dynamics of the filter net fisheries of the said estuary. The study utilized of questionnaires to obtain the data. It also considered personalinterviews and observation to validate the data. Results revealed that majorityof the respondents were married, have children ranging from 1-4, aged 26-40,finished elementary level of education, with no extended family. Majority of therespondents were engaged in fishing without alternative source of income. Ongear species accounting, most of the drift filter net fishers consumed 1-2 hoursper haul with alamang catch of 11-20 cans per haul and 9-10 hours per haulwith 1-5 kilograms per haul for the stationary filter net fishers. Majority of thefishers have 3-4 hauls per day. On sales and sharing scheme of the drift filter netfishers, majority of the drift filter net fishers had sales of 10,000 and below perfishing trip, majority of the fishermen had a share of 500.00 per fishing trip. Asto the respondents’ involvement in community activities, most of them joinedcommunity activities despite the fact that they do not hold any position in thecommunity. There were 19 identified species that were caught by the drift filternet (DFN) and stationary filter net (SFN) for the months of May & June, withrespect to moon phases. Catch per unit effort of “saplar” was higher than that of“banwar”.Keywords: Aquatic Ecology, catch, effort, Filter Net Fisheries, descriptive design,Cagayan, Philippines

scholarly journals The Role of Environmental Factors on the Fishery Catch of the Squid Uroteuthis chinensis in the Pearl River Estuary, China

2021 ◽  
Vol 9 (2) ◽  
pp. 131
Author(s):  
Dongliang Wang ◽  
Lijun Yao ◽  
Jing Yu ◽  
Pimao Chen
Keyword(s):  
River Estuary ◽  
Pearl River Estuary ◽  
Sea Surface ◽  
Spatiotemporal Variability ◽  
Pearl River ◽  
Coastal Current ◽  
Catch Per Unit Effort ◽  
Chl A ◽  
The Pearl River Estuary ◽  
The Pearl River

The Pearl River Estuary (PRE) is one of the major fishing grounds for the squid Uroteuthis chinensis. Taking that into consideration, this study analyzes the environmental effects on the spatiotemporal variability of U. chinensis in the PRE, on the basis of the Generalized Additive Model (GAM) and Clustering Fishing Tactics (CFT), using satellite and in situ observations. Results show that 63.1% of the total variation in U. chinensis Catch Per Unit Effort (CPUE) in the PRE could be explained by looking into outside factors. The most important one was the interaction of sea surface temperature (SST) and month, with a contribution of 26.7%, followed by the interaction effect of depth and month, fishermen’s fishing tactics, sea surface salinity (SSS), chlorophyll a concentration (Chl a), and year, with contributions of 12.8%, 8.5%, 7.7%, 4.0%, and 3.1%, respectively. In summary, U. chinensis in the PRE was mainly distributed over areas with an SST of 22–29 °C, SSS of 32.5–34‰, Chl a of 0–0.3 mg × m−3, and water depth of 40–140 m. The distribution of U. chinensis in the PRE was affected by the western Guangdong coastal current, distribution of marine primary productivity, and variation of habitat conditions. Lower stock of U. chinensis in the PRE was connected with La Niña in 2008.

Fish and invertebrate by-catch in the crab pot fishery in the Isle of Man, Irish Sea

2017 ◽  
Vol 98 (8) ◽  
pp. 2099-2111
Author(s):  
Fikret Öndes ◽  
Michel J. Kaiser ◽  
Lee G. Murray
Keyword(s):  
Irish Sea ◽  
Target Species ◽  
Catch Per Unit Effort ◽  
Isle Of Man ◽  
Ecosystem Effects ◽  
By Catch ◽  
Catch Rates ◽  
Taxonomic Groups ◽  
Catch Composition ◽  
Autumn And Winter

Baited trap or pot fisheries are considered to have relatively few wider ecosystem effects on the marine environment, particularly when compared with towed mobile fishing gear. However, this assumption is rarely tested in the field. This study aimed to determine the composition of non-target species that occur in crustacean pots and to assess spatial and temporal differences in catches in the waters around the Isle of Man, Irish Sea. The data were collected using fishery independent surveys and a questionnaire study. Based on fishery independent surveys, a total of five taxonomic groups and 43 species occurred as by-catch. The dominant by-catch species was velvet crab Necora puber. The by-catch per unit effort (BPUE) for all of the non-target species was low particularly in comparison to towed bottom gear fisheries around the Isle of Man. BPUE of species composition varied considerably between different locations around the Isle of Man. The results of both the fishery independent and questionnaire data suggested that the by-catch rates varied with season with peak BPUE occurring in spring which then declined into autumn and winter. By-catch composition did not decrease significantly with an increasing target species catch. Overall, by-catch was low relative to target species catch which may be partially attributable to the use of escape panels in pot fisheries in the Isle of Man.

Cadmium (Cd), Copper (Cu), and Zinc (Zn) levels in commercial and non-commercial fishes in the Blanakan River Estuary, Indonesia: A preliminary study

2021 ◽  
Vol 170 ◽  
pp. 112607
Author(s):  
Noverita Dian Takarina ◽  
Anna Ida Sunaryo Purwiyanto ◽  
Yulianto Suteja
Keyword(s):  
River Estuary ◽  
Preliminary Study

Aspects of the fishery, maturation and net selectivity of the wedge sole (Dicologoglossa cuneata) off south-western Iberia: implications for fishery management

2009 ◽  
Vol 90 (7) ◽  
pp. 1465-1474 ◽  
Author(s):  
Miguel Neves Santos ◽  
Pedro Gil Lino
Keyword(s):  
Fishery Management ◽  
River Mouth ◽  
Mesh Size ◽  
Scientific Basis ◽  
Catch Per Unit Effort ◽  
Important Species ◽  
Gill Net ◽  
Catch Rates ◽  
Log Normal ◽  
First Maturity

The wedge sole (Dicologoglossa cuneata, Moreau 1881) is a commercially important species for the artisanal fleet operating off the south-western Iberian Peninsula. During 2004 and 2005 a study was undertaken aiming to provide a scientific basis for management. Data collection included information on aspects of the fishery, spawning season, size at first maturity, tangle and gill-net selectivity. Seven nominal mesh sizes were used (40, 45 and 50 mm tangle nets and 40, 50, 60 and 70 mm gill-nets). Spawning lasts from December to June, with peaks in March and May. Length at first maturity for females was estimated at 18.5 cm. Catch rates decreased sharply with increasing mesh size, with tangle nets providing the highest yields. The log-normal selectivity model provided the best fit for specimens that were wedged. The higher catch-per-unit-effort of the smaller mesh sizes and the modal length of the fitted selectivity curve being below the size-at-maturity for wedge sole, suggests that the 50 mm nominal mesh size tangle net is the most appropriate for ensuring the fishery sustainability. Nevertheless, the minimum legal size should increase to at least 18 cm and a time–area closure should be implemented off the Guadiana River mouth.

scholarly journals Standardizing catch rates: is logbook information by itself enough?

2008 ◽  
Vol 65 (2) ◽  
pp. 255-266 ◽  
Author(s):  
J. Bishop ◽  
W. N. Venables ◽  
C. M. Dichmont ◽  
D. J. Sterling
Keyword(s):  
Relative Abundance ◽  
Prediction Models ◽  
Expert Knowledge ◽  
External Information ◽  
Linear Regression Models ◽  
Catch Per Unit Effort ◽  
Estimation Model ◽  
Catch Rates ◽  
Logbook Data ◽  
Estimation Models

Abstract Bishop, J., Venables, W. N., Dichmont, C. M., and Sterling, D. J. 2008. Standardizing catch rates: is logbook information by itself enough? – ICES Journal of Marine Science, 65: 255–266. The goal of the work was to maximize the accuracy of standardized catch per unit effort as an index of relative abundance. Linear regression models were fitted to daily logbook data from a multispecies penaeid trawl fishery in which within-vessel changes in efficiency are common. Two model-fitting strategies were compared. The predictive strategy focused on maximizing the explained variance, and the estimation strategy on finding realistic coefficients for important components of changing catchability. Realistic values could not always be obtained, because the regression factors were not orthogonal, and data on the presence of technology were sometimes unreliable or systematically incomplete. It was not possible to separate fishing power from abundance by analysing logbook data alone; it was necessary to incorporate external information within the standardization model. Therefore, the resultant estimation models incorporated external information and expert knowledge by offsets. There was no single best estimation model. Instead, a series of models provided an envelope of possible changes in relative fishing power and prawn abundance since 1970. Compared with the prediction models, the estimation models revealed different trends in relative fishing power and relative abundance.

scholarly journals Estudo preliminar do papel do hidrogênio como fonte alternativa de energia / Preliminary study of the role of hydrogen as an alternative source of energy

2020 ◽  
Vol 2 (4) ◽  
pp. 4028-4041
Author(s):  
Vinícius David Corraes ◽  
Maria das Graças Machado Freire ◽  
Thiago Muniz Barbosa
Keyword(s):  
Alternative Source ◽  
Preliminary Study

Black Bass Diversity: Multidisciplinary Science for Conservation

2015 ◽  
Keyword(s):  
Mixed Model ◽  
Micropterus Salmoides ◽  
Underlying Mechanism ◽  
Treated Wastewater ◽  
Fish Length ◽  
Catch Per Unit Effort ◽  
Explanatory Factors ◽  
Black Bass ◽  
Intersex Condition ◽  
Catch Rates

<em>Abstract</em>.—Reports of testicular oocytes (intersex) in fish are increasing worldwide. Intersex is often associated with estrogens in treated wastewater effluents, but few studies have explored other potentially explanatory factors. Our recent survey of intersex Largemouth Bass <em>Micropterus salmoides</em> in 11 impoundments across Georgia, USA found high incidence (>80%) of intersex fish in some impoundments but none in others. To explore factors associated with intersex in the impoundments, which did not receive wastewater, we examined potential predictor variables that varied among the levels of individual fish, impoundment, or landscape in a binomial mixed-model regression approach. Our model indicated effects of fish length, catch per unit effort (an index of fish density), and impoundment, which was the strongest effect. The probability of intersex was highest in smaller fish from impoundments with the highest catch rates. The underlying mechanism(s) for the impoundment effect remain unclear, but we hypothesize that estrogens excreted by high densities of fish and cyanobacteria may influence intersex. Additional studies are needed to understand the long-term population implications of intersex and the role of other biological and environmental factors, particularly at the impoundment level, in development of the intersex condition.

Conservation, Ecology, and Management of Catfish: The Second International Symposium

2011 ◽  
Keyword(s):  
Population Dynamics ◽  
Channel Catfish ◽  
Mississippi River ◽  
Upper Mississippi River ◽  
Catch Per Unit Effort ◽  
Blue Catfish ◽  
Resource Monitoring ◽  
Flathead Catfish ◽  
Unit Effort ◽  
Catch Rates

<em>Abstract</em>.—Using Long Term Resource Monitoring Program data collected from impounded (Pool 26) and unimpounded (Open River) reaches of the upper Mississippi River, we investigated population dynamics of flathead catfish <em>Pylodictis olivaris</em>, channel catfish <em>Ictalurus punctatus</em>, and blue catfish <em>I. furcatus</em> from random sites located in side channel border (SCB) and main channel border (MCB) habitats. Objectives were to (1) compare trends (1993–2007) of three catfishes collected in Pool 26 and Open River reaches of the upper Mississippi River, and (2) provide needed information to managers on population dynamics through time using a binary gear approach of active (i.e., daytime electrofishing) and passive gears (hoopnetting). Active gears resulted in a higher catch per unit effort (CPUE) of all catfishes in each habitat–reach combination as compared to passive gears. Passive gears resulted in negligible catches of blue catfish and flathead catfishes (e.g., mean of <1 fish/net night). Catch per unit effort using active gear resulted in a greater number of channel catfish captured in Pool 26 compared to the Open River, with Open River SCB habitat having the lowest CPUE in most years. Blue catfish in the Open River had a higher CPUE using active gear as compared to Pool 26, with the Open River MCB having the greatest CPUE. Flathead catfish had a higher CPUE in MCB habitat compared to SCB habitat, with the Open River MCB having the highest CPUE in most years. However, declining trends in flathead catfish appears to be occurring in Open River habitats while trends in flathead catfish appear to be slightly increasing in Pool 26. The most common length-classes captured were substock and stock-sized fish regardless of habitat, species, or reach. Trends for channel catfish were easily determined due to high catch rates; however, more monitoring and enhanced sampling is needed to accurately assess flathead catfish and blue catfish trends and to accurately determine demographics for all three species.

Linguistic Relativity in Fiji: A Preliminary Study

1997 ◽  
Vol 9 ◽  
pp. 69-74 ◽  
Author(s):  
Robin Taylor
Keyword(s):  
Extended Family ◽  
The Other ◽  
Relativity Theory ◽  
Linguistic Relativity ◽  
Extended Study ◽  
Experimental Support ◽  
The Family ◽  
Preliminary Study ◽  
Group Reading ◽  
The Individual

AbstractThere is a lack of experimental support for Linguistic Relativity Theory (LRT), which has not been tested in a South Pacific context. Fifty-two bilingual male (n = 26) and female Fijians read, and answered survey questions on the family dilemma, “An Unwanted Child?” - one group functioning in English and the other in Fijian. The group reading and answering in Fijian tended to place more emphasis on the rights of the extended family, whereas the group reading and responding in English placed more emphasis on the rights of the individual. These preliminary findings are consistent with LRT theory, and form the basis for more extended study, including perhaps a wider range of dilemmas and linguistic abilities (e.g., Fijians living in Australia).

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