Simultaneous Analysis of Multiple Length Frequency Data Sets when the Growth Rates Fluctuate between Years

SUMMARYThis study uses a novel method for discriminating cohorts and investigating the population dynamics of the parasitic crustacean, Argulus foliaceus. Analysis of parasite length-frequency data was carried out in order to elucidate the timings and drivers behind the parasite's life cycle. Up to 6 cohorts of the parasite emerge through the course of 1 year in still-water trout fisheries in England. Recruitment ceases over the winter months; however, 3 cohorts of the parasite over-winter, 2 as eggs and 1 as a hatched stage. The technique, when used in conjunction with temperature data, also allowed for the reliable prediction of growth rates and provided estimates of egg incubation times and the length of hatching periods. These data showed that growth rates increased exponentially between the observed temperatures of 4 to 22°C. The method allowed for the time taken from hatching to egg laying under field conditions to be predicted and produced estimates that were validated against independent laboratory studies on the growth of the parasite.

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Length-weight relationship, growth and mortality ofAnadara granosain Penang Island, Malaysia: an approach using length-frequency data sets

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315414001337 ◽

2014 ◽

Vol 95 (2) ◽

pp. 381-390 ◽

Cited By ~ 4

Author(s):

Mohammad Reza Mirzaei ◽

Zulfigar Yasin ◽

Aileen Tan Shau Hwai

Keyword(s):

Growth Parameters ◽

Total Mortality ◽

Growth Function ◽

Data Sets ◽

Frequency Data ◽

Length Frequency ◽

Frequency Distributions ◽

Weight Relationship ◽

Logarithmic Relationship ◽

Length Frequency Data

Length-weight relationship, growth parameters and mortality rates ofAnadara granosain the intertidal zone of Balik Pulau, Penang Island, West Coast of Malaysia were investigated based on monthly length-frequency data (December 2011 to November 2012). A total of 548 individuals ranging from 11.25 to 33.13 mm size were subjected to analysis. Logarithmic relationship between the length and weight was LogW = 2.328LogL − 2.537 (R2 = 0.922) for combined sexes. From this equation it was clear that the exponent ‘b’ value forA. granosashowed a negative allometric growth (b < 3). A von Bertalanffy growth function with an asymptotic length (L∞) of 35.40 mm and a growth constant (K) of 1.1 year−1was established from length frequency distributions. Thet0(−0.140) was estimated by substituting theL∞andKin the Pauly's equation. The sizes attained byA. granosawere 10.13, 14.36, 17.89, 20.82, 23.56 and 25.29 mm at the end of 2, 4, 6, 8, 10 and 12 months, respectively. The estimated growth performance index (Ø) was 3.13 while the estimated lifespan of the cockles was about 2.72 years at the study area. The estimated value of total mortality based on length-converted catch curve wasZ = 3.02 year−1. The natural mortality (M) and fishing mortality (F) rates were 1.84 and 0.48 year−1, respectively. The exploitation level (E) ofA. granosawas 0.20, which indicated slight fishing pressure on the stock.

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MULTIFAN a Likelihood-Based Method for Estimating Growth Parameters and Age Composition from Multiple Length Frequency Data Sets Illustrated using Data for Southern Bluefin Tuna (Thunnus maccoyii)

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f90-032 ◽

1990 ◽

Vol 47 (2) ◽

pp. 301-317 ◽

Cited By ~ 157

Author(s):

D. A. Fournier ◽

John R. Sibert ◽

Jacek Majkowski ◽

John Hampton

Keyword(s):

Growth Parameters ◽

Bluefin Tuna ◽

Parameter Estimates ◽

Data Sets ◽

Frequency Data ◽

Length Frequency ◽

Objective Criterion ◽

Southern Bluefin Tuna ◽

Robust Likelihood ◽

Length Frequency Data

We present a method for simultaneously analyzing multiple length frequency data sets. The method utilizes a robust likelihood-based estimation procedure that provides an objective criterion for hypothesis testing. The method is applied to length frequency data from southern bluefin tuna (Thunnus maccoyii) for which independent estimates of growth parameters based on tag return data are available. The estimates of the growth parameters from the new method were found to be in substantial agreement with the values previously obtained for these parameters. The strength of the likelihood approach is demonstrated by discriminating between alternative structural hypotheses for describing the data. The ability to simultaneously analyze multiple samples permits the method to exploit the extra information not available when analyzing samples one by one. The computer program maintains a database of fits to the data which enable the user to organize the results of the analysis. Graphical displays permit the user to view any of the fits, and an interactive graphics routine aids the user to find good initial parameter estimates.

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Changes in growth of juvenile southern bluefin tuna (Thunnus maccoyii): an analysis of length-frequency data from the Australian fishery

Marine and Freshwater Research ◽

10.1071/mf99029 ◽

2000 ◽

Vol 51 (2) ◽

pp. 143 ◽

Cited By ~ 16

Author(s):

George M. Leigh ◽

William S. Hearn

Keyword(s):

Modal Analysis ◽

Growth Rates ◽

Bluefin Tuna ◽

Frequency Data ◽

Length Frequency ◽

Southern Bluefin Tuna ◽

History Of ◽

The Mean ◽

Western Australian ◽

Length Frequency Data

Modal analysis is applied to historical length–frequency records of the Australian southern bluefin tunafishery, in order to quantify the variation in mean length from year to year. In the South Australian fishery in the first half of March, the mean length has ranged between 54 cm and 64 cm for 1-year-old fish, 73 cm and 85 cm for 2-year-old fish, and 85 cm and 100 cm for 3-year-old fish. The mean lengths of 2-, 3- and 4-year-old fish, and the increment from age 1 to age 3, have increased substantially over the history of the fishery. This increase in growth is probably a response to a decline in the population due to heavy fishing. In many years in the Western Australian fishery, two or more groups of 1-year-old fish were found: the mean lengths of these groups typically differed by 10 cm. Growth rates also varied markedly according to the season of the year.

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Carapace width-weight relationship, age, growth and longevity of the mud crab Scylla olivacea (Herbst, 1796) in the Pichavaram mangroves, south-east India

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315415001216 ◽

2015 ◽

Vol 96 (7) ◽

pp. 1379-1386 ◽

Cited By ~ 3

Author(s):

C. Viswanathan ◽

M. Pravinkumar ◽

T.V. Suresh ◽

V. Elumalai ◽

S.M. Raffi

Keyword(s):

East Coast ◽

Growth Parameters ◽

Carapace Width ◽

Data Sets ◽

Frequency Data ◽

Mud Crab ◽

Length Frequency ◽

Males And Females ◽

And Control ◽

Length Frequency Data

The present study provides novel information on carapace width-weight (CWR) relationship and growth parameters of the mud crab Scylla olivacea (Herbst, 1796) inhabiting the Pichavaram mangroves, east coast of India based on length frequency data sets during June 2010 to May 2012. CWR revealed linear regression between carapace width and weight in both sexes, and overall CWR exponent (b) values acquired for males and females are 3.035 (r2 = 0.962) and 2.925 (r2 = 0.933) respectively. The growth parameters, CW∞, K and to derived for males and females were 148.05, 0.762 year−1 and −0.637 and 138.80 mm, 0.856 year−1 and −0.681 respectively. The growth of S. olivacea was assessed through various methods in such a way that the outcome of one method functions as a rider, check and control over the other.

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Age, growth and maturity of a New Zealand endemic shark (Mustelus lenticulatus) estimated from vertebral bands

Marine and Freshwater Research ◽

10.1071/mf99012 ◽

2000 ◽

Vol 51 (1) ◽

pp. 35 ◽

Cited By ~ 10

Author(s):

Malcolm P. Francis ◽

Caoimhghin Ó Maolagáin

Keyword(s):

Growth Rates ◽

East Coast ◽

Growth Curves ◽

Von Bertalanffy ◽

Frequency Data ◽

Length Frequency ◽

Significant Difference ◽

Growth Bands ◽

Males And Females ◽

Length Frequency Data

Rig (Mustelus lenticulatus) specimens were aged by counting growth bands in whole vertebrae that were illuminated laterally with fibre-optic lights. Bands were counted by two readers who used information on the diameter of the vertebrae of new-born young and 1-year-old juveniles to identify the inner bands. The greatest estimated age was 12.1 years for a female of 137 cm total length, but few rig were more than 8 years old. For west coast South Island (WCSI) rig, there was no significant difference in growth rates of males and females. After pooling both sexes, there was no significant difference in growth rates between WCSI and east coast South Island (ECSI) rig. The combined WCSI and ECSI von Bertalanffy growth curve was Lt = 147.2 (1 – e −0.119[t + 2.35]). This curve agreed well with growth curves derived from length–frequency data, but validation of the ageing technique is still required. WCSI males mature at ~85 cm and 5–6 years, and females at ~100 cm and 7–8 years. ECSI rig probably mature at similar lengths and ages. Tagged rig have been recaptured after nearly 14 years at liberty. Longevity probably exceeds 15 years, and may exceed 20 years.

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POPULATION DYNAMICS OF MALAYAN LEAF FISH (Pristolepisgrooti Blkr.) IN RANAU LAKE, SOUTH SUMATRA

Indonesian Fisheries Research Journal ◽

10.15578/ifrj.24.2.2018.125-131 ◽

2018 ◽

Vol 24 (2) ◽

pp. 125

Author(s):

Sevi Sawetri ◽

Subagdja Subagdja ◽

Dina Muthmainnah

Keyword(s):

Mortality Rate ◽

Growth Parameters ◽

Total Mortality ◽

Natural Mortality ◽

Fishing Mortality ◽

Frequency Data ◽

Length Frequency ◽

Lake Ecosystems ◽

Exploitation Rate ◽

Length Frequency Data

The Malayan leaf fish or locally named as kepor (Pristolepis grooti) is one of important biotic components in Ranau Lake ecosystems. This study aimed to estimate population dynamic and exploitation rate of kepor in Ranau Lake, South Sumatera. The population parameters are estimated based on length frequency data which were collected in March to October 2013. Growth parameters and fishing mortality rates were calculated using FiSAT software package. The results showed that kepor’s growth was negative allometric, which tended to gain length faster than weight. Kepor population was dominated (42%) by individual length of 10.0 to 11.0 cm. Predicted length infinity (L) was 17.28 cm with high value of growth rates (K) of 1.4 year-1. The natural mortality rate (M) is 2.57 year-1, the fishing mortality rate (F) is 5.36 year-1 and total mortality rate (Z) is 7.93 year-1. The exploitation rate of Malayan leaf fish in Ranau Lake (E = 0.68 year-1) has passed the optimum score.

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Investigation and Development of Post-Season Modelling of Arrow Squid in the Snares and Auckland Islands

10.26686/wgtn.17003893 ◽

2021 ◽

Author(s):

◽

Vidette Louise McGregor

Keyword(s):

Automatic Differentiation ◽

Integrated Model ◽

Current Data ◽

Management Approach ◽

Frequency Data ◽

Catch Per Unit Effort ◽

Length Frequency ◽

Model Builder ◽

Set Up ◽

Length Frequency Data

<p>Squid fisheries require a different management approach to most fish species which are much longer living. Most squid live for around one year, spawn and then die. The result of this is an entirely new stock each year with little or no relationship of stock sizes between the years. Hence, it is difficult to set appropriate catch limits prior to the season. Currently, there is nothing set up for modelling the New Zealand squid fishery in-season or post-season. In-season management would allow for adjustments of catch limits during a season. Post-season management would provide information on how much the stock was exploited during a season (described as the escapement). I have produced an integrated model using ADMB (Automatic Differentiation Model Builder) (Fournier et al., 2011) which models length frequency data, CPUE (Catch Per Unit Effort) indices and catch weights from a season. It calculates escapement which indicates how much the fishery is currently being exploited. In running the model against data from four area and year combinations, I found the escapement calculation to be stable. The results suggest this modelling approach could be used with the current data collected for post-season modelling of the fishery. I am less confident about in-season modelling with the current data collected. The integrated model fits quite poorly to the CPUE data, suggesting some discrepancy either between the data or the assumptions made of them. Sampling from a greater number of tows is recommended to improve the length frequency data and this may also improve the ability of the model to fit both to these and the CPUE.</p>

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Investigation and Development of Post-Season Modelling of Arrow Squid in the Snares and Auckland Islands

10.26686/wgtn.17003893.v1 ◽

2021 ◽

Author(s):

◽

Vidette Louise McGregor

Keyword(s):

Automatic Differentiation ◽

Integrated Model ◽

Current Data ◽

Management Approach ◽

Frequency Data ◽

Catch Per Unit Effort ◽

Length Frequency ◽

Model Builder ◽

Set Up ◽

Length Frequency Data

<p>Squid fisheries require a different management approach to most fish species which are much longer living. Most squid live for around one year, spawn and then die. The result of this is an entirely new stock each year with little or no relationship of stock sizes between the years. Hence, it is difficult to set appropriate catch limits prior to the season. Currently, there is nothing set up for modelling the New Zealand squid fishery in-season or post-season. In-season management would allow for adjustments of catch limits during a season. Post-season management would provide information on how much the stock was exploited during a season (described as the escapement). I have produced an integrated model using ADMB (Automatic Differentiation Model Builder) (Fournier et al., 2011) which models length frequency data, CPUE (Catch Per Unit Effort) indices and catch weights from a season. It calculates escapement which indicates how much the fishery is currently being exploited. In running the model against data from four area and year combinations, I found the escapement calculation to be stable. The results suggest this modelling approach could be used with the current data collected for post-season modelling of the fishery. I am less confident about in-season modelling with the current data collected. The integrated model fits quite poorly to the CPUE data, suggesting some discrepancy either between the data or the assumptions made of them. Sampling from a greater number of tows is recommended to improve the length frequency data and this may also improve the ability of the model to fit both to these and the CPUE.</p>

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KORELASI PARAMETER MORFOMETRIK, NISBAH KELAMIN DAN KOMPOSISI UKURAN IKAN PEDANG (Xiphias gladius L.) DI SAMUDERA HINDIA

BAWAL Widya Riset Perikanan Tangkap ◽

10.15578/bawal.6.3.2014.155-162 ◽

2015 ◽

Vol 6 (3) ◽

pp. 155

Author(s):

Bram Setyadji ◽

Budi Nugraha

Keyword(s):

Body Size ◽

Standard Form ◽

Fork Length ◽

Secondary Data ◽

Primary Data ◽

Frequency Data ◽

Length Frequency ◽

Lower Jaw ◽

Length Measurements ◽

Length Frequency Data

Model pengkajian stok melalui data frekuensi panjang lebih banyak digunakan karena data tersebut paling banyak tersedia dan mudah didapatkan dibandingkan data pengukuran jaringan keras (sisik, otolith, sirip dan tulang belakang) dan tagging. Khusus untuk ikan pedang, data panjang yang tersedia sebagian besar tidak standar dikarenakan ikan pedang yang tertangkap langsung diproses di laut yang mana bagian kepala, sirip, isi perut dibuang. Oleh karena itu dibutuhkan persamaan empiris untuk konversi dari ukuran non-standar ke standar sehingga bisa digunakan sebagai basis data pengkajian stok yang berbasis data tersebut. Data primer merupakan hasil observasi laut selama kurun waktuMaret 2011 sampai dengan Desember 2013, sedangkan data sekunder merupakan data observasi ilmiah Loka Penelitian Perikanan Tuna periode 2005-2013. Hasil penelitian menunjukkan terdapat korelasi yang signifikan antara beberapa parametermorfometrik ikan pedang yang diukur yakni panjang dari pangkal sirip dada ke ujung lekukan tengah sirip ekor (LJFL), panjang dari mata ke ujung lekukan tengah sirip ekor (EFL) dan panjang dari ujung rahang bawah ke ujung lekukan tengah sirip ekor (PFL) (R2 > 0,97; P < 0,01), akan tetapi tidak ada perbedaan yang nyata antara morfometri ikan pedang dan jenis kelamin (EFL-LJFL, P > 0,05 dan PFL-LJFL, P > 0,05). Hubungan antara nisbah kelamin dengan panjang ikan signifikan (Nisbah Kelamin = 0,0175 LJFL – 3,1001; n = 6, selang kelas 5 cm; P < 0,01) yang mana ikan pedang dengan ukuran lebih dari 260 cmadalah betina.Stock assessment models using length frequency data are more frequently used by Indonesian scientist due to its availability and easily obtained rather than skeletal parts or tagging data. As for swordfish most of the data vailable are not in standard form because most of swordfish landed are usually dressed at sea with various ways, so the length measurement are possible done afterward. There fore conversion among different length measurements is a necessity for assessment and management purposes. Primary data was collected from scientific observer program conducted between March 2011 and December 2013, while secondary data was obtained from 2005-2013. The results showed that the models are fit quite well for Lower Jaw Fork Length (LJFL), Eye Orbit Fork Length (EOFL) and Pectoral Fork Length (PFL) (R2> 0.97; P < 0.01) and there was no significant relationship between morphometric and sex (EFL-LJFL, P > 0.05 and PFL-LJFL, P > 0.05). Correlation between sex ratio and body size proved to be significant with nearly all of the swordfish >260 cm was female.

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