scholarly journals Female reproductive biology and spawning periodicity of two species of king prawns, Penaeus longistylus Kubo and Penaeus latisulcatus Kishinouye, form Queensland's East Coast Fishery

1988 ◽  
Vol 39 (6) ◽  
pp. 729 ◽  
Author(s):  
AJ Courtney ◽  
MCL Dredge
Keyword(s):  
Egg Production ◽  
East Coast ◽  
Sea Water ◽  
Coastal Region ◽  
Ovary Development ◽  
Commercial Catch ◽  
Ovary Weight ◽  
Species Population ◽  
Spawning Periodicity ◽  
Catch Rates

In the coastal region of central Queensland female red-spot king prawns, P. longistylus, and the western or blue-leg king prawns, P. latisulcatus, had high mean ovary weights and high proportions of advanced ovary development during the winter months of July and August of 1985 and 1986. On the basis of insemination, both species began copulating at the size of 26-27 mm CL, but P. longistylus matured and spawned at a smaller size than P. latisulcatus. Abundance of P. longistylus was generally three to four times greater than that of P. latisulcatus but the latter was subject to greater variation in abundance. Low mean ovary weight and low proportions of females with advanced ovaries were associated with the maximum mean bottom sea-water temperature (28.5�C) for both species. Population fecundity indices indicated that peaks in yolk or egg production (a) displayed a similar pattern for both species, (b) varied in timing from year to year for both species and (c) were strongly influenced by abundance. Generally, sample estimates of abundance and commercial catch rates (CPUE) showed similar trends. Differences between the two may have been due to changes in targeted commercial effort in this multi-species fishery.

Stock assessment of the blue grenadier Macruronus novaezelandiae resource off south-eastern Australia

2001 ◽  
Vol 52 (4) ◽  
pp. 701 ◽  
Author(s):  
A. E. Punt ◽  
D. C. Smith ◽  
R. B. Thomson ◽  
M. Haddon ◽  
X. He ◽  
...  
Keyword(s):  
Egg Production ◽  
Stock Assessment ◽  
Production Method ◽  
Integrated Analysis ◽  
Absolute Abundance ◽  
Commercial Catch ◽  
Eastern Australia ◽  
Class Strength ◽  
Catch Rates ◽  
Spawning Biomass

The fishery can be divided into two subfisheries (‘spawning’ and ‘non-spawning’). Commercial catch rates for the ‘non-spawning’ subfishery declined from the late 1980s to 1997, whereas those for the ‘spawning’ subfishery exhibit no obvious temporal trend. An ‘Integrated Analysis’ assessment, of the feasibility of reconciling these differing trends, uses catch (landed and discarded), catch rate, length-at-age, and catch-at-age data and estimates of absolute abundance based on the egg-production method. It emphasizes uncertainty due to model assumptions and the data included in the assessment. Use of the discard data allows more precise estimation of the magnitude of recent recruitments. Spawning biomass is estimated to have declined from a peak in 1989–91 to 1999 although fishing mortality has consistently been <6%for each subfishery. One main reason for the reduction in population size is the weakness of year-classes spawned from 1988 to 1993. Differences in catch rates between the two subfisheries can therefore be explained by interactions between the components of the population harvested by the two ‘subfisheries’, and the trends in year-class strength. A risk analysis is used to evaluate the consequences of different future levels of harvest for different assessment assumptions. Overall, the spawning biomass is predicted to increase over the next five to ten years as a result of the strong 1994 and 1995 year-classes, although the extent of this increase remains uncertain.

Schooling behaviour of jack mackerel, Trachurus declivis (Jenyns), observed in the Tasmanian purse seine fishery

1993 ◽  
Vol 44 (4) ◽  
pp. 577 ◽  
Author(s):  
H Williams ◽  
G Pullen
Keyword(s):  
School Size ◽  
East Coast ◽  
Diurnal Changes ◽  
Jack Mackerel ◽  
Schooling Behaviour ◽  
Summer Schools ◽  
By Catch ◽  
Catch Rates ◽  
Lunar Effects ◽  
Purse Seine Fishery

The seasonal, lunar and diurnal changes in schooling of jack mackerel were examined using log-book information collected from an industrial fishery off the east coast of Tasmania between 1985 and 1989. School size increased significantly from spring to autumn. The ratio between surface and subsurface schools encountered by the fishery also changed seasonally. Surface schools predominate during summer, whereas subsurface schools become more frequent during autumn. The fishery was predominantly a day fishery and no lunar effects on catch rates or fishing intensity were detected. Catches mainly comprised jack mackerel, although redbait (Emmelichthys nitidus Richardson) and blue mackerel (Scomber australasicus Cuvier) were a significant by-catch. In summer, schools were almost exclusively composed of jack mackerel, but in other seasons mixed schools were found. Data presented, together with evidence from other sources, suggest that the availability of schools to the fishery may be closely related to the availability of feed.

Validity of using translucent zones of otoliths to age the pilchard Sardinops sagax neopilchardus from Albany, Western Australia

1996 ◽  
Vol 47 (4) ◽  
pp. 617 ◽  
Author(s):  
WJ Fletcher ◽  
SJ Blight
Keyword(s):  
Western Australia ◽  
Age Groups ◽  
Growth Curves ◽  
Relative Number ◽  
Older Individuals ◽  
Commercial Catch ◽  
Monthly Basis ◽  
Lower Accuracy ◽  
Sardinops Sagax ◽  
Catch Rates

Otoliths (sagittae) of the pilchard (Sardinops sagax neopilchardus) from the Albany region of Western Australia were examined on a monthly basis during 1989 to 1991. When read consecutively, with the month of capture known, a clear annual cycle of an increase in marginal increments to October followed by a decline was recorded. This pattern was, however, severely distorted when samples were re-examined after having been jumbled and the month of capture concealed. Younger age groups (≤3) showed evidence of multiple rings being formed annually, but not in all years or individuals, and this was not evident in older individuals (≥4). Agreement between readings was low (43-53%), especially between different readers. Resultant growth curves showed that males grow to a smaller size (L∞ =164, K = 0.805, Φ = 1.03) than females (L∞ = 174, K = 0.584, Φ= 0.95). Agreement between counts of annuli and ages estimated by using otolith weight and length was only 54% for all individuals, but increased to 76% for individuals assigned the same age by different readers. Given the poorer predictions of future catch rates from the relative number of 2-year-olds in the commercial catch using annuli (implying lower accuracy) and increased complexity in preparation, otolith weights will be the method adopted for future ageing.

scholarly journals Kajian Potensi Air Tanah Berdasarkan Data Geolistrik Resistiviti Untuk Antisipasi Kekeringan Di Wilayah Pesisir Kangkung, Kabupaten Kendal, Privinsi Jawa Tengah

2017 ◽  
Vol 20 (1) ◽  
pp. 35 ◽  
Author(s):  
Sugeng Widada ◽  
Alfi Satriadi ◽  
Baskoro Rochaddi
Keyword(s):  
Groundwater Quality ◽  
Ground Water ◽  
Coastal Area ◽  
Sea Water ◽  
Coastal Region ◽  
Pumping Test ◽  
Dry Season ◽  
Sea Water Intrusion ◽  
Groundwater Exploitation ◽  
Water Intrusion

Coastal Region of Kangkung, Kendal Regency, Central Java Province is one of the areas that experiencing water in the dry season. Groundwater exploitation is one way solution to meet the water needs for people in the area, especially in the dry season. Therefore it is necessary to study potency of ground water in coastal area of Kangkung. The research was  conducted to determine the potential of ground water in the confined aquifer in the Coastal Region of Kangkung, Kendal District which is expected to be utilized as a source of water to meet the needs of local communities. The method used in this research is  descriptive analysis to describe the condition of aquifer, however some things are delivered quantitatively. The aquifer condition was obtained from the interpretation of geoelectricity (resistivity) data supported by geological and hydrogeological observation data and pumping test data as secondary data. Groundwater quality analysis and simple hydrochemical analysis is with Chlorida - Bicarbonat Ratio (CBR) method to know the possibility of sea water intrusion. The results showed that the aquifer in the coastal area of Kangkung has the potential of 29.13 lt / sec ground water discharge which can be utilized to meet the needs of clean water 18,800 people. Although it is adjacent to the sea, the groundwater in the study area does not undergo sea water intrusion. Groundwater quality in this location is qualified as raw drinking water according to SK Menkes No, 492/Menkes/Per/IV2010 tentang Persyaratan Kualitas Air Minum. Keywords: ground water, geoelectric, intrusion  Wilayah Pesisir Kangkung, Kabupaten Kendal Provinsi Jawa Tengah merupakan salah satu daerah yang pada musim kemarau mengalami kekeringan. Pemanfaatan air tanah merupakan salah satu cara untuk memenuhi kebutuhan air bagi masyarakat di daerah tersebut, terutama pada musim kemarau. Oleh karena itu perlu dilakukan kajian potensi air tanah di daerah Pesisir Kangkung tersebut. Penelitian ini bertujuan untuk mengetahui potensi air tanah pada akuifer dalam (tertekan) di Wilayah Pesisir Kangkung, Kabupaten Kendal yang diharapkan dapat dimanfaatkan sebagai sumber air bersih untuk memenuhi kebutuhan masyarakat setempat. Metode penelitian yang digunakan dalam penelitian ini adalah diskriptis analisis untuk menggambarkan kondisi akuifer, namun demikian beberapa hal disampaikan secara kuantitatif. Kondisi akuifer diperoleh dari hasil interpretasi data geolistrik resistiviti dengan didukung data hasil pengamatan geologi dan hidrogeologi serta data sekunder berupa hasil pumping test. Analisa kualitas air tanah dan analisis hidrokimia secara sederhana dengan metode Chlorida – Bicarbonat Ratio (CBR) dilakukan untuk mengetahui kemungkinan terjadinya intrui air laut. Hasil penelitian menujukan bahwa akuifer di daerah Pesisir Kangkung mempunyai potensi debit air tanah 29,13 lt/det yang dapat dimanfaatkan untuk memenuhi kebutuhan air bersih 18.800 orang. Meskipun berbatasan dengan laut, namun air tanah di daerah kajian tidak mengalami  terintrusi air laut. Kualitas air tanah di lokasi ini memenuhi syarat sebagai bahan baku air minum sesuai SK Menkes No, 492/Menkes/Per/IV2010 tentang Persyaratan Kualitas Air Minum. Kata Kunci : air tanah, geolistrik, intrusi

scholarly journals Lunar periodicity in catch rate and reproductive condition of adult eastern king prawns, Penaeus plebejus, in coastal waters of south-eastern Queensland, Australia

1996 ◽  
Vol 47 (1) ◽  
pp. 67 ◽  
Author(s):  
AJ Courtney ◽  
DJ Die ◽  
JG McGilvray
Keyword(s):  
Coastal Waters ◽  
Full Moon ◽  
Lunar Cycle ◽  
Catch Rate ◽  
Lunar Phase ◽  
Reproductive Condition ◽  
Ovary Weight ◽  
South Eastern ◽  
New Moon ◽  
Catch Rates

This study examined the lunar and die1 variation in catch rates and reproductive condition of adult eastern king prawns, Penaeus plebejus, in relatively deep (160 m) coastal waters off south- eastern Queensland. Females numerically dominated catches over most of the lunar cycle and constituted 76% of the weight of the catch. Analysis of variance (ANOVA) revealed an interaction between lunar phase and sex; catches peaked during Lunar Phase 3 (full moon � 3 days) and were particularly marked for males. This was the only period during the lunar cycle when the sex ratio approached 1 : 1. There was also an interaction between trawl-time and sex; male catch rates were at a minimum early in the evening, whereas female catch rates were at a maximum then and declined throughout the night. Trawler logbook catch rate data from the same area over a similar period indicated an interaction between lunar cycle and lunar phase. ANOVA revealed an effect of the interaction between phase and sex on the incidence of soft prawns; the incidence of soft males increased during Phase 4 (half moon waning to new moon � 3 days). Ovary weight also varied between phases and was higher during Phases 2 (half moon waxing to full moon � 3 days) and 4 (half moon waning to new moon � 3 days). Trends in the ovary weight and the incidence of histologically mature and ripe females suggested there are two periods of increased spawning activity during each lunar cycle. A cyclic regression fitted to the data explained 93% of the variation in the incidence of ripe females between samples. The influence of these cyclic trends in catch rate and reproductive condition should be considered when monitoring the spawning stock in the fishery and when planning sampling strategies in any future reproductive studies.

Fecundity of the American Plaice, Hippoglossoides platessoides (Fabr.) from Grand Bank and Newfoundland Areas

1964 ◽  
Vol 21 (3) ◽  
pp. 597-612 ◽  
Author(s):  
T. K. Pitt
Keyword(s):  
Egg Production ◽  
Fish Length ◽  
Northern Slope ◽  
Southern Slope ◽  
Ovary Weight ◽  
Length Relationship ◽  
Relationship Of ◽  
Hippoglossoides Platessoides

Fecundity estimates were made on a total of 140 mature American plaice from the southern and northern slopes of the Grand Bank and from St. Mary's Bay. Log–log relationships were established between fecundity and fish length, gutted and gilled weight, age, and ovary weight. No differences were found to exist between the fecundity–length relationship of plaice from the three areas, but there is a suggestion that within areas there may be annual differences in egg production. At comparable ages plaice from the southern slope of the Grand Bank are larger in size and produce more eggs than those from the northern slope and St. Mary's Bay.

Production of donor-derived eggs after ovarian germ cell transplantation into the gonads of adult, germ cell-less, triploid hybrid fish†

2020 ◽  
Vol 103 (6) ◽  
pp. 1289-1299
Author(s):  
Dongdong Xu ◽  
Tasuku Yoshino ◽  
Marcelo de Bello Cioffi ◽  
Hiroyuki Yoshikawa ◽  
Yasuko Ino ◽  
...  
Keyword(s):  
Germ Cell ◽  
Cell Transplantation ◽  
Dna Sequences ◽  
Egg Production ◽  
Expression Patterns ◽  
Ovary Development ◽  
Specific Gene ◽  
Suitable Model ◽  
Triploid Hybrid ◽  
Germ Cell Transplantation

Abstract In animals, spermatogonial transplantation in sterile adult males is widely developed; however, despite its utility, ovarian germ cell transplantation is not well developed. We previously showed that the interspecific hybrid offspring of sciaenid was a suitable model for germ cell transplantation studies as they have germ cell-less gonads. However, all these gonads have testis-like characteristics. Here, we tested whether triploidization in hybrid embryos could result in germ cell-less ovary development. Gonadal structure dimorphism and sex-specific gene expression patterns were examined in 6-month-old triploid hybrids (3nHybs). Thirty-one percent of 3nHybs had germ cell-less gonads with an ovarian cavity. cyp19a1a and foxl2, ovarian differentiation-related genes, were expressed in these gonads, whereas dmrt1 and vasa were not expressed, suggesting ovary-like germ cell-less gonad development. Some (26%) 3nHybs had testis-like germ cell-less gonads. Ovarian germ cells collected from homozygous green fluorescent protein (GFP) transgenic blue drum (BD) (Nibea mitsukurii) were transplanted into 6-month-old 3nHybs gonads via the urogenital papilla or oviduct. After 9 months, the recipients were crossed with wild type BD. Among the six 3nHyb recipients that survived, one female and one male produced fertile eggs and motile sperm carrying gfp-specific DNA sequences. Progeny tests revealed that all F1 offspring possessed gfp-specific DNA sequences, suggesting that these recipients produced only donor-derived eggs or sperm. Histological observation confirmed donor-derived gametogenesis in the 3nHyb recipients’ gonads. Overall, triploidization reduces male-biased sex differentiation in germ cell-less gonads. We report, for the first time, donor-derived egg production in an animal via direct ovarian germ cell transplantation into a germ cell-less ovary.

scholarly journals The reproductive performance of the Red-Algae shrimp Leander paulensis (Ortmann, 1897) (Decapoda, Palaemonidae) and the effect of post-spawning female weight gain on weight-dependent parameters

2015 ◽  
Vol 63 (3) ◽  
pp. 207-216 ◽  
Author(s):  
Uwe Zimmermann ◽  
Fabrício Lopes Carvalho ◽  
Fernando L. Mantelatto
Keyword(s):  
Weight Gain ◽  
Egg Production ◽  
Reproductive Output ◽  
Coastal Region ◽  
Reproductive Traits ◽  
Development Stage ◽  
Female Size ◽  
Egg Volume ◽  
Average Fecundity ◽  
Female Weight

AbstractDecapod species have evolved with a variety of reproductive strategies. In this study reproductive features of the palaemonid shrimp Leander paulensiswere investigated. Individuals were collected in the coastal region of Ubatuba, São Paulo, Brazil. In all, 46 ovigerous females were examined in terms of the following reproductive traits: fecundity, reproductive output, brood loss and egg volume. Leander paulensis produces a large number of small eggs with an average fecundity of 635 ± 246 eggs. Egg volume increased significantly from early (0.034 ± 0.008 mm3) to late development stage (0.05 ± 0.012 mm3). The reproductive output did not correlate with female size. The weight of females bearing stage 2 eggs was significantly higher than that of females carrying stage 1 eggs. We assume that the reason for this weight gain is the recovery of female reserves that have been depleted for egg production. Moreover, we emphasize that this weight gain must be considered when evaluating weight-dependent variables such as reproductive output or brood loss in relation to female weight. Otherwise, an overestimation of these variables might lead to inaccurate results.

scholarly journals Improving the quality of information on Scottish anglerfish fisheries: making use of fishers' data

2008 ◽  
Vol 65 (7) ◽  
pp. 1334-1345 ◽  
Author(s):  
H. Dobby ◽  
L. Allan ◽  
M. Harding ◽  
C. H. Laurenson ◽  
H. A. McLay
Keyword(s):  
Temporal Trends ◽  
Poor Quality ◽  
Quality Of Information ◽  
Commercial Catch ◽  
Size Category ◽  
History Of ◽  
Scientific Technical ◽  
Catch Rates ◽  
Management Advice

Abstract Dobby, H., Allan, L., Harding, M., Laurenson, C. H., and McLay, H. A. 2008. Improving the quality of information on Scottish anglerfish fisheries: making use of fishers’ data. – ICES Journal of Marine Science, 65: 1334–1345. In recent years, the International Council for the Exploration of the Sea (ICES) Working Group on the Assessment of Northern Shelf Demersal Stocks has been unable to provide an analytical assessment for anglerfish. One of the reasons for this has been the poor quality of the commercial catch-and-effort data, with ICES and the European Commission’s Scientific, Technical, and Economic Committee for Fisheries (STECF) stressing the need for reliable information on which to base estimates of stock status. In response, and following consultation with the fishing industry, an anglerfish tallybook project was implemented in Scotland as part of a long-term approach to providing better data. Tallybooks are completed on a haul-by-haul basis. Skippers record catches of anglerfish (by size category) and other species where possible, together with information on haul location, duration, and depth. Individual vessel catch rates are calculated and used to provide insights into temporal trends in the stock and the spatial distribution of the fishery. The history of the fishery and management advice are summarized, and an overview of the tallybook project is provided. Catch rates are analysed using a generalized additive modelling approach which incorporates seasonal, annual, spatial, and vessel-dependent effects. The results show increased catch rates between 2006 and 2007.

How reliable are the abundance indices derived from commercial catch–effort standardization?

2009 ◽  
Vol 66 (7) ◽  
pp. 1169-1178 ◽  
Author(s):  
Yimin Ye ◽  
Darren Dennis
Keyword(s):  
Generalized Linear Model ◽  
Observation Error ◽  
Potential Bias ◽  
Catch Per Unit Effort ◽  
Rock Lobster ◽  
Commercial Catch ◽  
Abundance Indices ◽  
Catch Rates ◽  
Power Component ◽  
Stock Abundance

Commercial catch-per-unit-effort (CPUE) data are often standardized to construct indices of stock abundance. The value of such standardization lies in the improvement in the proportionality between the derived index and true abundance. Using the Torres Strait rock lobster ( Panulirus ornatus ) fishery in Australia as an example, we first standardized the commercial CPUE data using a generalized linear model (GLM) and then fitted observation error models to the resulting abundance indices and independent abundance data (as estimated by research diver surveys) to examine the proportionality. While the GLM standardization greatly improved proportionality in comparison with the nonstandardized commercial catch rates, it could produce biased results if the model did not explicitly incorporate variables that had caused changes in fishing efficiency. As most catch–effort standardizations do not model the fishing power component simultaneously, this result may serve as a warning to the potential bias in stock abundance indices extracted from GLMs that are underfitted.

Sign in / Sign up

Export Citation Format

Share Document