Stock Assessment and Life History of a Newly Discovered Alaska Surf Clam (Spisula polynyma) Resource in the Southeastern Bering Sea

1981 ◽  
Vol 38 (10) ◽  
pp. 1173-1181 ◽  
Author(s):  
Steven E. Hughes ◽  
Neil Bourne
Keyword(s):  
Bering Sea ◽  
Stock Assessment ◽  
Maximum Sustainable Yield ◽  
North Coast ◽  
Catch Per Unit Effort ◽  
Surf Clam ◽  
The North ◽  
Management Measures ◽  
History Of ◽  
Slow Growing

A 1977 exploratory survey of subtidal clam resources in the southeastern Bering Sea revealed extensive concentrations of Alaska surf clams (Spisula polynyma) along the north coast of the Alaska Peninsula. Using east coast hydraulic clam harvesters, subsequent 1977 and 1978 stock assessment surveys delineated a geographically isolated stock with an estimated exploitable biomass of 329 000 ± 52 000 t and conservatively calculated potential annual yield of 25 017 t (maximum sustainable yield) of whole clams. Production fishing trials at 13 sites in 1978 produced an average catch per unit effort of 815 kg/h with a 1.84-m-wide clam harvester.Life history studies indicated the species is long-lived (25 yr), slow growing (K = 0.135), fully recruited to the spawning population at 8 yr of age, subject to low natural mortality (conservatively calculated as M = 0.19), and attains maximum cohort biomass at ages between 9.4 and 13.0 yr. Biological rationale for management measures is presented.Key words: population assessment, sustained yield, surf clams, Alaska

scholarly journals The demersal fish composition and catch per unit effort of mini bottom trawl at the coast of Demak Regency Central Java

2021 ◽  
Vol 322 ◽  
pp. 03006
Author(s):  
Naliyana Fitriya ◽  
Nahlah Alfiatuunisa ◽  
Suwarman Partsuwiryo ◽  
Eko Setyobudi
Keyword(s):  
Demersal Fish ◽  
Bottom Trawl ◽  
North Coast ◽  
Catch Per Unit Effort ◽  
The North ◽  
Central Java ◽  
Unit Effort ◽  
Trichiurus Lepturus ◽  
Trawl Fishing ◽  
Trawl Catches

Demak is a coastal area on the North Coast of Java with a large enough potential for demersal fish resources. This research aimed to determine the composition, the length and weight distribution, and catch per unit effort (CPUE) of demersal fish caught using mini bottom trawl at the north coast of Demak Regency. The research was carried out in October-December 2020 by observation of ten trips of mini bottom trawl fishing. Each fish captured was then grouped by type, identified, and measured its length and weight. The result showed that 38 species consist of 31 fishes, four mollusks, and three crustaceans. The fish captured dominated by pony fish (Leiognathus equulus) as much as 31.23% and largehead hairtail (Trichiurus lepturus) of 23.52%. The catch per unit effort (CPUE) average of mini bottom trawl was 44.77 kg/trip. Mainly fish (more than 95%) caught in small size compared it’s the maximum attainable length (L-max), with all the weight ranges from 0.3 to 520 g and more than 98% sized 0.3-80 g. Mini bottom trawl catches many types of fish and small size; therefore, mini bottom trawl is classified as a type of fishing gear with a very low selectivity level.

South America—Andes

2017 ◽  
Author(s):  
George F. Lau
Keyword(s):  
South America ◽  
North Coast ◽  
Small Worlds ◽  
Fertility Status ◽  
The North ◽  
Form Function ◽  
History Of

This chapter details major figurine developments in the ancient Andes and discusses new understandings based on figurine form, function, and imagery. Great formal diversity characterizes the long history of their use. The most active traditions occurred along the coast, while data from the highlands and eastern slopes are more limited. Certain regions, especially the north coast, show longevity in the use of figurines, especially in household, funerary, and offering contexts. Figurines were important for their role in embodying identity (e.g. gender, fertility, status) as well as alterity. Production and ritual embued them with divine powers and agency. Figurine use and imagery also show dual structures, often manifested in gendered pairs or object sets. Finally, Andean figurines were important for their interactions with other contexts and things, including other figurine-like items: they inspired their own small worlds of sociality.

The Use and Construction History of Huaca Prieta, North Coast of Peru

2020 ◽  
pp. 101-128
Author(s):  
Tom D. Dillehay
Keyword(s):  
Late Pleistocene ◽  
North Coast ◽  
Marine Resources ◽  
Human Presence ◽  
Social Correlates ◽  
The North ◽  
History Of ◽  
Chicama Valley ◽  
North Coast Of Peru

Chapter 4 summarizes the construction, subsistence, and social correlates of Huaca Prieta, a mound site in the lower Chicama Valley on the north coast of Peru, from the earliest evidence of human presence in the Late Pleistocene (ca. 12,500 14C BP) through abandonment at 3,800 14C BP. Marine resources were important throughout the sequence, which saw an early advent of agriculture and increasing population, complexity, and monumentality.

Eels at the Edge: Science, Status, and Conservation Concerns

2009 ◽  
Keyword(s):  
New Zealand ◽  
Management System ◽  
Stock Assessment ◽  
Catch Per Unit Effort ◽  
Commercial Catch ◽  
The North ◽  
Anguilla Australis ◽  
Unit Effort ◽  
Access Rights ◽  
Quota Management

<em>Abstract.</em>—The New Zealand eel fishery comprises two species, the shortfin eel <em>Anguilla australis </em>and the New Zealand longfin eel <em>A. dieffenbachii</em>. A third species, the speckled longfin eel <em>A. reinhardtii</em>, is present in small numbers in some areas. Major fisheries in New Zealand are managed under the Quota Management System. Individual transferable quotas are set as a proportion of an annual total allowable commercial catch. The Quota Management System was introduced into the South Island eel fishery on 1 October 2000 and the North Island fishery on 1 October 2004. Freshwater eels have particular significance for customary Maori. Management policies allow for customary take and the granting of commercial access rights on introduction into the Quota Management System. Eel catches have remained relatively constant since the early 1970s. The average annual catch from 1989–1990 to 2001–2002 (fishing year) was 1,313 mt. Catch per unit effort remained constant from 1983 to 1989 and reduced from 1990 to 1999. Statistically significant declines in catch per unit effort for New Zealand longfin eel were found in some areas over the latter period. For management, an annual stock-assessment process provides an update on stock status.

Holkham Salts Hole, an Isolated Salt-Water pond with Relict Features. An Account Based on Studies by the late C. F. A. Pantin

1971 ◽  
Vol 51 (3) ◽  
pp. 717-741 ◽  
Author(s):  
O. D. Hunt
Keyword(s):  
Salt Marshes ◽  
Sea Water ◽  
Salt Water ◽  
High Water ◽  
North Coast ◽  
Marine Fauna ◽  
The North ◽  
Short Period ◽  
History Of ◽  
Water Pond

A saline pond known as the ‘Salts Hole’ at Holkham on the north coast of Norfolk is situated between the pine-covered sand-hills and the fields that have been reclaimed for agriculture from pre-existing salt-marshes. It has a salinity of about 75% of that of sea water and supports a peculiar relict marine fauna. Except for the rare occurrence of flooding for a short period, as in the great storm of 1953, the pond has probably been cut off from the sea for about 250 years. It presents three problems: how it got its fauna and flora; how its marine character is maintained; and how the pond originated geographically. The fauna and flora, as described, show the pond as a refuge where various marine and brackish species have managed to maintain themselves and co-exist in water outside their normal and differing ranges of salinity. The main character of the pond is kept remarkably constant with respect to salinity, alkalinity, temperature and oxygenation. The pond is a study in ‘natural engineering’, constituting a natural marine aquarium with natural controls. It is fed near the level of high-water neap tide by continuous flow from a salt spring of very constant salinity supplied from water contained in the extensive coastal sands. Its only apparent artificial feature is the outlet controlled by a dam through a culvert into a ditch that conveys its water through the fields to the sea at Wells nearly two miles away. Search in the muniment room at Holkham Hall brought to light maps dating back to Elizabethan days which show the history of the Salts Hole.

scholarly journals KARAKTERISTIK PERIKANAN TERI (ENGRAULIDAE) DI PANTAI UTARA JAWA-MADURA

2021 ◽  
Vol 26 (3) ◽  
pp. 135
Author(s):  
ACHMAD ZAMRONI ◽  
Heri Widiyastuti ◽  
Suwarso Suwarso
Keyword(s):  
North Coast ◽  
Small Scale ◽  
Fishing Gear ◽  
Eastern Region ◽  
Northern Coast ◽  
Catch Per Unit Effort ◽  
Fishing Season ◽  
The North ◽  
Fishing Vessels ◽  
Landing Sites

Perikanan teri berkembang sangat pesat khususnya di perairan utara Jawa Madura pada tahun terakhir ini. Kajian tentang karakteristik perikanan teri (Engraulidae) di sepanjang pantai utara Jawa-Madura dilaksanakan pada tahun 2017-2018, meliputi sebaran usaha perikanan, tipe armada-alat penangkapan ikan, aspek operasional penangkapan, hasil tangkapan-kelimpahan dan musim penangkapan ikan teri. Pengumpulan data pendaratan ikan teri dilakukan melalui survey di 11 lokasi pendaratan ikan. Hasil penelitian menunjukkan terdapat 12 lokasi tempat pendaratan utama ikan teri di sepanjang pantai utara (pantura) Jawa dan Madura. Dua jenis alat dominan digunakan untuk penangkapan teri adalah pukat cincin dan payang; perikanan bersifat skala kecil, melakukan trip harian, dengan armada kapal penangkap berukuran dibawah 20 GT. Jaring umumnya menggunakan waring dengan mata jaring kecil (3/8 inch) di bagian kantong. Daerah penangkapan di perairan pantai yang dangkal, dekat dengan basis perikanan. Musim penangkapan ikan teri bervariasi, di wilayah bagian barat (Pulolampes, Larangan, Morodemak) berlangsung sekitar musim timur/tenggara (Mei Juli), sedangkan di wilayah bagian timur berlangsung pada awal musim timur dan berjalan cukup lama hingga bulan November (musim peralihan 2). Hasil tangkapan per unit upaya (CPUE, sebagai indek kelimpahan) diduga makin ke arah timur semakin rendah namun disertai musim penangkapan ikan lebih lama. Anchovy fishery has grown rapidly, especially in the northern waters of Java-Madura in the last year. The study on the characteristics of the anchovy fishery (Engraulidae) along the northern coast of Java-Madura was carried out in 2017-2018, covering the distribution of fisheries effort, types of fishing gear, operational aspects of fishing, catch-abundance and fishing season. The collection of anchovy landing data was carried out through a survey at 11 fish landing sites. The results showed that there were 12 main anchovy landing sites along the north coast (pantura) of Java and Madura. Two types of dominant fishing gear used for anchovies are purse seine and payang; Fisheries are small-scale, undertaking daily trips, with a fleet of fishing vessels under 20 GT. The nets generally use “waring” with small mesh (3/8 inch) in the codend. Fishing area in shallow coastal waters, close to the fishing base. The fishing season for anchovy varies, in the western region (Pulolampes, Larangan, Morodemak) it takes place around the east / southeast season (May-July), while in the eastern region it takes place at the beginning of the eastern season and lasts quite a long time until November (transition season 2) . The catch per unit effort (CPUE, as an abundance index) is thought to be getting lower eastward but accompanied by a longer fishing season.

scholarly journals Application of dynamic factor analysis in the assessment of Iberian anglerfish stocks

2008 ◽  
Vol 65 (7) ◽  
pp. 1362-1369 ◽  
Author(s):  
Manuela Azevedo ◽  
Rafael Duarte ◽  
Fátima Cardador ◽  
Pedro Sousa ◽  
Celso Fariña ◽  
...  
Keyword(s):  
Factor Analysis ◽  
Stock Assessment ◽  
Intrinsic Rate ◽  
Maximum Sustainable Yield ◽  
Dynamic Factor Analysis ◽  
Parameter Estimates ◽  
Dynamic Factor ◽  
Catch Per Unit Effort ◽  
Biomass Dynamic ◽  
Lower Maximum

Abstract Azevedo, M., Duarte, R., Cardador, F., Sousa, P., Fariña, C., Sampedro, P., Landa, J., and Costas, G. 2008. Application of dynamic factor analysis in the assessment of Iberian anglerfish stocks. – ICES Journal of Marine Science, 65: 1362–1369. Dynamic factor analysis (DFA) was applied to six time-series of catch per unit effort data of the Iberian (ICES Divisions VIIIc and IXa) white anglerfish (Lophius piscatorius) and black anglerfish (L. budegassa). Results showed that grouping the abundance indices reflected the fleet's area of exploitation and fish size selection. Two common trends (CTs) were extracted for each species, capturing the main signal of abundance over time. The white anglerfish was assessed using these CTs as input to the biomass dynamic model currently used in the ICES assessment, to investigate whether the approach would reduce the uncertainty in parameter estimates and related quantities. Using the CTs, bias estimates are lower. The current perception of an overexploited stock is unchanged, but a much lower intrinsic rate of biomass increase was estimated, indicating that the biomass recovery might be much slower. A lower maximum sustainable yield, ∼3600 t, was obtained, and this is more consistent with the historical landings trajectory. The application of DFA to stock assessment of anglerfish, presented here for the first time, can be extended to age-based assessments.

Joseph-Fidele Bernard On the Bering Sea frontier (1921–1922)

Polar Record ◽  
1977 ◽  
Vol 18 (115) ◽  
pp. 341-349
Author(s):  
Glynn Barratt
Keyword(s):  
Bering Sea ◽  
Direct Contact ◽  
Final Phase ◽  
Soviet State ◽  
The Third ◽  
North East ◽  
The North ◽  
North Eastern ◽  
History Of ◽  
The Bering Sea

In a great number of articles now, Soviet historians have dealt with the attractive theme of the enormity of western, and especially American, activities on the north-eastern fringes of Siberia—activities which, starting in the 1860's, lasted for three quarters of a century. Yet, showing no disrespect to scholars of the stamp of N. Zhikharev, S. V. Bakhrushin, and M. I. Belov, through the operation of one underlying tendency all these accounts of western penetration of Chukotka may be regarded as comprising one large group. For 40 years they have tended, if not wholly to ignore the final phase of North American commercial ‘intervention’ in Chukotka in the years following 1920, then at least to place no emphasis whatever on the awkward facts, for instance, that ‘friendly direct contact between Alaska's and Chukotka's natives went on for several years’ and that some trips between the continents ‘went on until as late as 1944’. The reasons for this are not hard to find: Chukotkan history of the third decade is potentially embarrassing to Moscow. In 1921 the question of whether or not Chukotka formed a part of the Soviet state had not been settled, nor was absolute authority exercised in the remote north-east by the Bolsheviks at that point or, indeed, in 1922. Now a White Russian force would dominate an area, now a detachment of the Japanese army. Worse, there was hostility towards the Bolsheviks in Chukotka even after the demise of the anti-Bolshevik leader Bochkarev in 1923. But more embarrassing than any anti-Bolshevik or petty-bourgeois sentiment, there can be no doubt, has proved the tiresome fact that Moscow blessed the trips to Anadyr' and other points on the Chukotkan littoral made by western schooner masters. Here is the rub: for the new government ‘found it convenient to encourage some American traders to continue, because the Government's own communications with Chukotka were so uncertain’.

Impacts of spatial scales of fisheries and environmental data on catch per unit effort standardisation

2009 ◽  
Vol 60 (12) ◽  
pp. 1273 ◽  
Author(s):  
Siquan Tian ◽  
Yong Chen ◽  
Xinjun Chen ◽  
Liuxiong Xu ◽  
Xiaojie Dai
Keyword(s):  
Spatial Scale ◽  
Stock Assessment ◽  
Spatial Scales ◽  
Additive Models ◽  
Environmental Data ◽  
Catch Per Unit Effort ◽  
The North ◽  
Unit Effort ◽  
Data Collection And Analysis ◽  
North Western

Spatial scale is an important factor that needs to be considered in data collection and analysis in ecological studies. Studies focusing on the quantitative evaluation of impacts of spatial scales are, however, limited in fisheries. Using the Chinese squid-jigging fishery in the north-western Pacific Ocean as an example, we evaluated impacts of spatial scale used in grouping fisheries and environmental data on the standardisation of fisheries catch per unit effort (CPUE). We developed 18 scenarios of different spatial scales with a combination of three latitudinal levels (0.5°, 1° and 2°) and six longitudinal levels (0.5°, 1°, 2°, 3°, 4° and 5°) to aggregate the data. We then applied generalised additive models to analyse the 18 scenarios of data for the CPUE standardisation, and quantified differences among the scenarios. This study shows that longitudinal and latitudinal spatial scale and size of the spatial area for data aggregation can greatly influence the standardisation of CPUE. We recommend that similar studies be undertaken whenever possible to evaluate the roles of spatial scales and to identify the optimal spatial scale for data aggregations in the standardisation of CPUE and fisheries stock assessment.

The Castanheira Site: New Evidence on the Antiquity and History of the Ananatuba Phase (Marajó Island, Brazil)

1969 ◽  
Vol 34 (4) ◽  
pp. 402-410 ◽  
Author(s):  
Mario F. Simões
Keyword(s):  
Geographical Distribution ◽  
Formative Period ◽  
Eastern Coast ◽  
North Coast ◽  
The North ◽  
History Of ◽  
Marajó Island ◽  
The Right ◽  
New Evidence

AbstractThe geographical distribution of the Ananatuba phase has been extended to the eastern coast of Marajó by the discovery of J-26: Castanheira on the right bank of the middle Rio Camará. Two stratigraphic cuts were excavated, and the pottery obtained was classified into the types established by Meggers and Evans (1957). The resulting seriated sequence shows trends of ceramic change parallel to theirs and a similar intrusion of Mangueiras phase sherds in the upper levels of the deposit. Interdigitation of the J-26 levels into the seriated sequence for the Ananatuba phase shows the new site to occupy a relatively late position, supporting the earlier inference of expansion from the north coast toward the southeast during the history of the phase. A charcoal sample obtained from Cut 1, Level 40-50 cm., and correlating with the appearance of Mangueiras phase sherds in the refuse, gave the date of 980 B.C. ± 200 (SI-385), which places the initial occupation of Marajó by pottery-making groups within the Formative period.

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