Management of Sea Herring Fisheries in the Northwest Atlantic

1973 ◽  
Vol 30 (12) ◽  
pp. 2444-2451 ◽  
Author(s):  
R. C. Hennemuth
Keyword(s):  
Socioeconomic Factors ◽  
Effective Control ◽  
Total Allowable Catch ◽  
Northwest Atlantic ◽  
Stock Size ◽  
Spawning Stock ◽  
Rational Management ◽  
Regulatory Measures ◽  
Territorial Water ◽  
First Time

Regulatory measures for herring set by the International Commission for the Northwest Atlantic Fisheries (ICNAF) represent an important milestone in international fishery regulation because for the first time, they provide for national quotas in addition to a total catch limitation.The first regulatory measures were proposed in January 1972 to be effective that same year. In January 1973, the effects of the 1972 catch on the stock were evaluated, national quotas for 1973 were proposed, and conditional allowable catches for 1974 were proposed depending on stock size at the end of 1973. The 1972 catch, which according to preliminary statistics was within the total allowable catch, caused a further decrease in stock size. The effectiveness of the proposed 1973–74 quotas in increasing stock size depends on the sizes of the 1970 and 1971 year-classes entering the fishery in 1973 and 1974.Major problems in negotiating these regulations were caused by biological and socioeconomic factors. Biological factors included: population structure — several stocks involved, and parts of them are in nonconvention waters; assessment of effects of fishing — difficult because of rapid fishery development and because there are separate fisheries on adults and juveniles; fishery status — reductions up to 64% from 1971 catches required to prevent further spawning stock decreases. Socioeconomic factors included: allocation — general principles not previously applied, complications from new entrants, newly developing fisheries, and territorial-water fisheries; non-members; immediate action — normal procedures would prevent effective control in 1972; nonconvention waters — significant portions of the fishery not under ICNAF control; economic impact — severe reductions in existing fisheries and curtailment of developing national fisheries; administration — control technically difficult because of species and size mixture.Solutions to these problems arrived at by ICNAF are discussed, and seven general requirements for rational management are derived: adequate fishery statistics; assessment of effects of fishing; clearly defined objectives; workable techniques of regulation; principles for allocation; effective international inspection; effective enforcement.

Development of National Quotas by the International Commission for the Northwest Atlantic Fisheries

1973 ◽  
Vol 30 (12) ◽  
pp. 2427-2435 ◽  
Author(s):  
M. S. Edelman ◽  
I. I. Dokuchaev
Keyword(s):  
Mesh Size ◽  
Complex Problem ◽  
Scientific Data ◽  
International Commission ◽  
Standing Committee ◽  
Northwest Atlantic ◽  
Fish Stocks ◽  
Regulatory Measures ◽  
First Time ◽  
Principal Species

The Northwest Atlantic Ocean is one of the areas where fish stocks have been subjected to exceedingly high fishing pressure by many European and American countries, to the extent that some of them require strict control. International cooperation has been achieved through the International Commission for the Northwest Atlantic Fisheries (ICNAF). The Commission has applied conservation measures following scientific advice from various panels and committees, and stands as the first example of the application of national quotas for major exploited species.By 1967, increases in total catches in the ICNAF Area were accompanied by decreases in the catch per unit of effort, and it became apparent that regulations on mesh size were not sufficient to maintain the stocks. The Standing Committee on Regulatory Measures was created to consider alternative regulations, and the economic and administrative problems connected with them. A Committee on Research and Statistics was charged with preparation of scientific data on status of the stocks and measures necessary to maintain and restore them.As early as 1968, proposals were made to establish total catch quotas for principal species and to allocate these among the countries fishing. Adoption of this kind of regulation involved amendments to the Convention, and decisions were therefore difficult to achieve without a long and detailed study.At the 1969 meeting, many stocks had declined further and stricter quotas were applied. The Commission recommended changes in the Convention to allow regulations to be made on economic and technical as well as on scientific data; this was the first step on the way to fixing national quotas. The Standing Committee on Regulatory Measures recommended overall quotas for the principal species and that these quotas be shared among participating nations, taking into account interests of states with developing fisheries, states whose fleets are incapable of being diverted to other fisheries, special interests of coastal states, and historical landings. The weight to be given to these various factors was left for further negotiations.At the 1970 meeting, as only four member countries had ratified the agreements on national quotas, this problem remained unsolved. In 1971, despite further declines in catch and better research data, the Commission was still unable to agree on national quotas. But at an extraordinary meeting in January and February 1972, total quotas were established for herring in particular areas, and for national quotas. Thus for the first time in history national quotas were accepted by fishing countries. Later, overall and national quotas were recommended for the other principal species. It is hoped that this experience will be useful to other international bodies in resolving this complex problem.

The invasive aphid Pterochloroides persicae (Cholodkovsky, 1899) (Hemiptera: Aphidoidea: Lachninae) recorded on important fruit trees in Kashmir Valley, India

2018 ◽  
Vol 10 (5) ◽  
pp. 11672 ◽  
Author(s):  
Govindasamy Mahendiran ◽  
Shahid Ali Akbar ◽  
Mudasir Ahmad Dar
Keyword(s):  
Management Practices ◽  
Fruit Trees ◽  
Kashmir Valley ◽  
Central Institute ◽  
Rational Management ◽  
First Time

Pterochloroides persicae (Cholodkovsky, 1899) is reported here for the first time from the Kashmir Valley. The aphid is seen to infest almond, peach, plum orchards in the region.  Monitoring of the pest was carried out in the peach and almond fields of the Central Institute of Temperate Horticulture (CITH) during the years 2014–2016. Seasonality and bio-rational management practices of the pest are discussed. 

scholarly journals Molecular Survey of Vector-Borne Pathogens of Dogs and Cats in Two Regions of Saudi Arabia

Pathogens ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 25
Author(s):  
Abdullah D. Alanazi ◽  
Abdulaziz S. Alouffi ◽  
Mohamed S. Alyousif ◽  
Mohammad Y. Alshahrani ◽  
Hend H. A. M. Abdullah ◽  
...  
Keyword(s):  
Saudi Arabia ◽  
Real Time ◽  
Real Time Pcr ◽  
Bartonella Henselae ◽  
Public Awareness ◽  
Effective Control ◽  
Vector Borne Diseases ◽  
Babesia Vogeli ◽  
Vector Borne ◽  
First Time

Dogs and cats play an important role as reservoirs of vector-borne pathogens, yet reports of canine and feline vector-borne diseases in Saudi Arabia are scarce. Blood samples were collected from 188 free-roaming dogs and cats in Asir (70 dogs and 44 cats) and Riyadh (74 dogs), Saudi Arabia. The presence of Anaplasma spp., Bartonella spp., hemotropic Mycoplasma spp., Babesia spp., and Hepatozoon spp. was detected using a multiplex tandem real-time PCR. PCR-positive samples were further examined with specific conventional and real-time PCR followed by sequencing. Dogs from Riyadh tested negative for all pathogens, while 46 out of 70 dogs (65.7%) and 17 out of 44 cats (38.6%) from Asir were positive for at least one pathogen. Positive dogs were infected with Anaplasma platys (57.1%), Babesia vogeli (30%), Mycoplasma haemocanis (15.7%), and Bartonella henselae (1.4%), and cats were infected with Mycoplasma haemofelis (13.6%), Candidatus Mycoplasma haemominutum (13.6%), B. henselae (9.2%), and A. platys (2.27%), all of which are reported for the first time in Saudi Arabia. Co-infection with A. platys and B. vogeli was detected in 17 dogs (24.28%), while coinfections were not detected in cats. These results suggest that effective control and public awareness strategies for minimizing infection in animals are necessary.

Fistulicola plicatus (Cestoda) and Tristoma spp. (Trematoda) on Swordfish from the Northwest Atlantic

1971 ◽  
Vol 28 (1) ◽  
pp. 31-38 ◽  
Author(s):  
Christine Iles
Keyword(s):  
Body Length ◽  
Outer Surface ◽  
Northwest Atlantic ◽  
Xiphias Gladius ◽  
First Time ◽  
Biological Tags

Data on the incidence, location, and morphology of the scolex of Fistulicola plicatus in 24 specimens of swordfish (Xiphias gladius) from the northwest Atlantic are given. The occurrence of normal scolices in tubular sheaths or bladderlike cysts on the outer surface of the rectum is recorded for the first time for this species. The incidence and location on the gills of Tristoma coccineum and T. integrum are given and the possibility of using these monogenetic trematodes as biological tags is discussed. The increase in the number of dorsomarginal rows of comb teeth with body length for immature specimens of T. coccineum is demonstrated.

scholarly journals Switching from a Unicellular to Multicellular Organization in an Aspergillus niger Hypha

mBio ◽  
2015 ◽  
Vol 6 (2) ◽  
Author(s):  
Robert-Jan Bleichrodt ◽  
Marc Hulsman ◽  
Han A. B. Wösten ◽  
Marcel J. T. Reinders
Keyword(s):  
Aspergillus Niger ◽  
Fluorescent Protein ◽  
Stress Conditions ◽  
Physical Contact ◽  
Effective Control ◽  
Mobility Rate ◽  
Content Type ◽  
Green Fluorescent ◽  
First Time ◽  
Compound Concentration

ABSTRACT Pores in fungal septa enable cytoplasmic streaming between hyphae and their compartments. Consequently, the mycelium can be considered unicellular. However, we show here that Woronin bodies close ~50% of the three most apical septa of growing hyphae of Aspergillus niger. The incidence of closure of the 9th and 10th septa was even ≥94%. Intercompartmental streaming of photoactivatable green fluorescent protein (PA-GFP) was not observed when the septa were closed, but open septa acted as a barrier, reducing the mobility rate of PA-GFP ~500 times. This mobility rate decreased with increasing septal age and under stress conditions, likely reflecting a regulatory mechanism affecting septal pore diameter. Modeling revealed that such regulation offers effective control of compound concentration between compartments. Modeling also showed that the incidence of septal closure in A. niger had an even stronger impact on cytoplasmic continuity. Cytoplasm of hyphal compartments was shown not to be in physical contact when separated by more than 4 septa. Together, data show that apical compartments of growing hyphae behave unicellularly, while older compartments have a multicellular organization. IMPORTANCE The hyphae of higher fungi are compartmentalized by porous septa that enable cytosolic streaming. Therefore, it is believed that the mycelium shares cytoplasm. However, it is shown here that the septa of Aspergillus niger are always closed in the oldest part of the hyphae, and therefore, these compartments are physically isolated from each other. In contrast, only part of the septa is closed in the youngest part of the hyphae. Still, compartments in this hyphal part are physically isolated when separated by more than 4 septa. Even open septa act as a barrier for cytoplasmic mixing. The mobility rate through such septa reduces with increasing septal age and under stress conditions. Modeling shows that the septal pore width is set such that its regulation offers maximal control of compound concentration levels within the compartments. Together, we show for the first time that Aspergillus hyphae switch from a unicellular to multicellular organization.

scholarly journals An explicit solution for calculating optimum spawning stock size from Ricker’s stock recruitment model

PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e1623 ◽  
Author(s):  
Mark D. Scheuerell
Keyword(s):  
Explicit Solution ◽  
Model Fitting ◽  
Maximum Sustainable Yield ◽  
Reference Points ◽  
Stock Size ◽  
Points Of Interest ◽  
Spawning Stock ◽  
Stock Recruitment ◽  
Explicit Formulae ◽  
Recruitment Model

Stock-recruitment models have been used for decades in fisheries management as a means of formalizing the expected number of offspring that recruit to a fishery based on the number of parents. In particular, Ricker’s stock recruitment model is widely used due to its flexibility and ease with which the parameters can be estimated. After model fitting, the spawning stock size that produces the maximum sustainable yield (SMSY) to a fishery, and the harvest corresponding to it (UMSY), are two of the most common biological reference points of interest to fisheries managers. However, to date there has been no explicit solution for either reference point because of the transcendental nature of the equation needed to solve for them. Therefore, numerical or statistical approximations have been used for more than 30 years. Here I provide explicit formulae for calculating bothSMSYandUMSYin terms of the productivity and density-dependent parameters of Ricker’s model.

scholarly journals Development of the elements of the biological system for protecting crops against the southern green stink bug Nezara viridula L. (Hemiptera: Pentatomidae) in Krasnodar Krai

2020 ◽  
Vol 21 ◽  
pp. 00037
Author(s):  
Marina Pushnya ◽  
Elena Rodionova ◽  
Ekaterina Snesareva
Keyword(s):  
Crop Protection ◽  
Nezara Viridula ◽  
Effective Control ◽  
Stink Bug ◽  
Krasnodar Krai ◽  
Southern Green Stink Bug ◽  
Green Stink Bug ◽  
The Russian Federation ◽  
First Time ◽  
Significant Spread

The article considers the issues related to the development of the methods of biological crop protection against the adventive species of pentatomides (Pentatomidae, Hemiptera) – the southern green stink bug Nezara viridula L. 1758. One of the main factors contributing to the significant spread of this multinucleated pest is the lack of effective control systems of this species, in particular, poor knowledge of local entomophages species. A number of the biological peculiarities of a stinkbug has been studied. For the first time in the Russian Federation, infection of the N. viridula eggs with the entomophage Trissolcus basalis Woll. 1858 (Hymenoptera: Scelionidae) was determined We found that to control Nezara in such crops as soybeans, tomatoes and tobacco, it is possible to use the Fitoverm-M preparation (active ingredient – aversectin-C, 2 g/l).

scholarly journals Evaluation of the absolute levels of acoustic estimates of the 1983 year class of Norwegian spring-spawning herring

2003 ◽  
Vol 60 (3) ◽  
pp. 480-485 ◽  
Author(s):  
Ingolf Røttingen ◽  
Sigurd Tjelmeland
Keyword(s):  
Working Group ◽  
Assessment Model ◽  
Stock Size ◽  
Blue Whiting ◽  
Realistic Picture ◽  
Absolute Sense ◽  
Spawning Stock ◽  
The Absolute

Abstract The 1983 year class of Norwegian spring-spawning herring was large and, in retrospect, increased the spawning stock by more than two million tons when it recruited in 1987–1988. This paper summarizes and evaluates the acoustic estimates of the 1983 year class in the period 1983–2001. The key to the evaluation is a minimum stock based on the number of the 1983 year class caught in the international fishery and the year-class estimates made by the ICES Northern Pelagic and Blue Whiting Fisheries Working Group in 2002 using the SeaStar assessment model. The period of analysis covers a change in instrumentation, around 1990, from the SIMRAD EK400/Nord integrator to the EK500/BEI integrator system. The application of the acoustic estimates in the assessment and management of this herring stock is reviewed. It is concluded that the stock size was underestimated when the acoustic estimates were used in an absolute sense in the 1980s. In the 1990s the acoustic estimates were tuned to stock-size indices obtained from other methodologies and this approach seems to have given a realistic picture of the development of the 1983 year class.

scholarly journals Evaluating management strategies to implement the recovery plan for Iberian hake (Merluccius merluccius); the impact of censored catch information

2009 ◽  
Vol 67 (2) ◽  
pp. 258-269 ◽  
Author(s):  
Ernesto Jardim ◽  
Santiago Cerviño ◽  
Manuela Azevedo
Keyword(s):  
Management Strategies ◽  
Maximum Sustainable Yield ◽  
Sustainable Yield ◽  
Fishing Mortality ◽  
Merluccius Merluccius ◽  
Total Allowable Catch ◽  
Recovery Plan ◽  
Stock Biomass ◽  
Spawning Stock ◽  
The Impact

Abstract Jardim, E., Cerviño, S., and Azevedo, M. 2010. Evaluating management strategies to implement the recovery plan for Iberian hake (Merluccius merluccius); the impact of censored catch information. – ICES Journal of Marine Science, 67: 258–269. Iberian hake assessment revealed an increase in fishing mortality (F) despite enforcement of a recovery plan. Recent landings exceeded the total allowable catch and discarding rates were high. Alternative management strategies based on F control were evaluated with respect to the probability of recovering spawning-stock biomass (SSB), expected profits, and robustness to uncertainty on catch information and stock dynamics. Results showed that the use of censored catch data, i.e. excluding the Gulf of Cádiz or discards, may lead to inappropriate conclusions. Reducing fishing mortality was necessary for SSB to recover. An Fmax strategy with discard reduction showed the highest probability of rebuilding SSB and led the fishery to sustainable exploitation, with an expected %SPR of 30–40% in 2025, mean individual weight in the landings of 450 g in 2015, and yield increasing by >20%. Because of uncertainty in the estimates of maximum sustainable yield, management strategies based on FMSY were least robust, but all strategies were robust to alternative stock–recruit models.

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