scholarly journals Improved estimates of age, growth and reproduction for the regionally endemic Galapagos sailfin grouperMycteroperca olfax(Jenyns, 1840)

PeerJ ◽  
2015 ◽  
Vol 3 ◽  
pp. e1270 ◽  
Author(s):  
Paolo Usseglio ◽  
Alan M. Friedlander ◽  
Edward E. DeMartini ◽  
Anna Schuhbauer ◽  
Eva Schemmel ◽  
...  
Keyword(s):  
Growth Function ◽  
Management Plan ◽  
Parameter Estimates ◽  
Size At Maturity ◽  
Fishery Resource ◽  
Galapagos Archipelago ◽  
Von Bertalanffy Growth Function ◽  
Mean Size ◽  
Growth And Reproduction

The Galapagos Sailfin grouper,Mycteroperca olfax, locally known as bacalao and listed as vulnerable by the IUCN, is culturally, economically, and ecologically important to the Galapagos archipelago and its people. It is regionally endemic to the Eastern Tropical Pacific, and, while an important fishery resource that has shown substantial declines in recent years, to date no effective management regulations are in place to ensure the sustainability of the Galapagos fishery for this species. Previous estimates of longevity and size at maturity for bacalao are inconsistent with estimates for congeners, which brings into question the accuracy of prior estimates. We set out to assess the age, growth, and reproductive biology of bacalao in order to provide more accurate life history information to inform more effective fisheries management for this species. The oldest fish in our sample was 21 years old, which is 2–3 times greater than previously reported estimates of longevity. Parameter estimates for the von Bertalanffy growth function (k= 0.11,L∞= 110 cm TL, andto= − 1.7 years) show bacalao to grow much slower and attain substantially larger asymptotic maximum length than previous studies. Mean size at maturity (as female) was estimated at 65.3 cm TL, corresponding to a mean age of 6.5 years. We found that sex ratios were extremely female biased (0.009 M:1F), with a large majority of the individuals in our experimental catch being immature (79%). Our results show that bacalao grow slower, live longer, and mature at a much larger size and greater age than previously thought, with very few mature males in the population. These findings have important implications for the fishery of this valuable species and provide the impetus for a long-overdue species management plan to ensure its long-term sustainability.

scholarly journals Age, growth and reproduction of the Galapagos sailfin grouper Mycteroperca olfax (Jenyns, 1840): an overdue and needed comprehensive baseline

2015 ◽  
Author(s):  
Paolo Usseglio ◽  
Alan M. Friedlander ◽  
Edward E. DeMartini ◽  
Anna Schuhbauer ◽  
Pelayo Salinas de Léon
Keyword(s):  
Growth Function ◽  
Management Plan ◽  
Parameter Estimates ◽  
Fishery Resource ◽  
Galapagos Archipelago ◽  
Von Bertalanffy Growth Function ◽  
History Information ◽  
Mean Size ◽  
Growth And Reproduction

The Galapagos Sailfin grouper, Mycteroperca olfax, locally known as bacalao and listed as vulnerable by IUCN, is culturally, economically, and ecologically important to the Galapagos archipelago and its people. It is regionally endemic to the Eastern Tropical Pacific, and, while an important fishery resource that has shown substantial declines in recent years, to date no effective management regulations are in place to ensure the sustainability of its Galapagos fishery. Previous estimates of longevity and size of maturity for bacalao are inconsistent with estimates for congeners, which questions the accuracy of prior estimates. We set out to rigorously assess the age, growth, and reproductive biology of bacalao in order to provide more accurate life history information to inform more effective fisheries management for this species. The oldest fish in our sample was 24 years old, which is 2-3 times greater than previously reported estimates of longevity. Parameter estimates for the von Bertalanffy growth function (k= 0.07, L∞= 119.1 cm TL, and to= -2.33 years) show bacalao to grow much slower and obtain substantially larger asymptotic maximum length than previous studies. Mean size at maturity (as female) was estimated at 61.1 cm TL, corresponding to an age of 7.8 years. As a protogynous hermaphrodite, size at sex change (from adult female to adult male) occurred at 83.7 cm TL, corresponding to 15.2 years of age. We found that sex ratios were extremely female biased (0.015 M:1F), with a large majority of the individuals in our experimental catch being immature (73%). Our results show that bacalao grow slower, live longer, and mature at a much larger size and greater age than previously thought, with very few mature males in the population. These findings have key implications for the fishery of this valuable species and urge for a long-due species management plan to ensure its long-term sustainability.

scholarly journals Age, growth and reproduction of the Galapagos sailfin grouper Mycteroperca olfax (Jenyns, 1840): an overdue and needed comprehensive baseline

2015 ◽  
Author(s):  
Paolo Usseglio ◽  
Alan M. Friedlander ◽  
Edward E. DeMartini ◽  
Anna Schuhbauer ◽  
Pelayo Salinas de Léon
Keyword(s):  
Growth Function ◽  
Management Plan ◽  
Parameter Estimates ◽  
Fishery Resource ◽  
Galapagos Archipelago ◽  
Von Bertalanffy Growth Function ◽  
History Information ◽  
Mean Size ◽  
Growth And Reproduction

The Galapagos Sailfin grouper, Mycteroperca olfax, locally known as bacalao and listed as vulnerable by IUCN, is culturally, economically, and ecologically important to the Galapagos archipelago and its people. It is regionally endemic to the Eastern Tropical Pacific, and, while an important fishery resource that has shown substantial declines in recent years, to date no effective management regulations are in place to ensure the sustainability of its Galapagos fishery. Previous estimates of longevity and size of maturity for bacalao are inconsistent with estimates for congeners, which questions the accuracy of prior estimates. We set out to rigorously assess the age, growth, and reproductive biology of bacalao in order to provide more accurate life history information to inform more effective fisheries management for this species. The oldest fish in our sample was 24 years old, which is 2-3 times greater than previously reported estimates of longevity. Parameter estimates for the von Bertalanffy growth function (k= 0.07, L∞= 119.1 cm TL, and to= -2.33 years) show bacalao to grow much slower and obtain substantially larger asymptotic maximum length than previous studies. Mean size at maturity (as female) was estimated at 61.1 cm TL, corresponding to an age of 7.8 years. As a protogynous hermaphrodite, size at sex change (from adult female to adult male) occurred at 83.7 cm TL, corresponding to 15.2 years of age. We found that sex ratios were extremely female biased (0.015 M:1F), with a large majority of the individuals in our experimental catch being immature (73%). Our results show that bacalao grow slower, live longer, and mature at a much larger size and greater age than previously thought, with very few mature males in the population. These findings have key implications for the fishery of this valuable species and urge for a long-due species management plan to ensure its long-term sustainability.

Age, growth and reproduction of the protandrous hermaphrodite fish, Sarpa salpa, from the Portuguese continental coast

2016 ◽  
Vol 98 (2) ◽  
pp. 269-281 ◽  
Author(s):  
Rafaela Barros Paiva ◽  
Ana Neves ◽  
Vera Sequeira ◽  
Ana Rita Vieira ◽  
Maria José Costa ◽  
...  
Keyword(s):  
Information Criterion ◽  
Growth Function ◽  
Population Parameters ◽  
Von Bertalanffy Growth Function ◽  
Protandrous Hermaphrodite ◽  
Sarpa Salpa ◽  
Back Calculation ◽  
First Maturity ◽  
Available Information ◽  
Growth And Reproduction

Salema, Sarpa salpa is a commercial exploited species in the Atlantic Ocean with little available information for the essential population parameters, such as age, growth and reproduction. The present study aims to describe these parameters for S. salpa obtained off the coast of Portugal. Ages were estimated from the whole otolith readings; the minimum and the maximum ages observed were 0 and 14 years, respectively, corresponding to 5.2 and 41.4 cm of total length (TL). Whole otolith readings and back-calculation approaches were used to estimate the parameters of the von Bertalanffy growth function and the Akaike's information criterion value suggested that the second approach was the best one to describe the growth of salema: L∞ = 45.07 cm, k = 0.14 year−1 and t0 = −1.43 year. The species is a protandric hermaphrodite and the sex change process occurred between 28.6 and 40.9 cm TL. A short spawning season was identified, extending from September to November. The estimated length at first maturity for males was 24.5 cm TL, corresponding to an age of 2 years at first maturity. This species exhibited a determinate fecundity type and the relative annual fecundity varied between 462 and 2662 oocytes per gram of gutted weight.

Growth and Recruitment of the Atlantic Seabob Shrimp, Xiphopenaeus kroyeri (Heller, 1862) (Decapoda, Penaeidae), on the Coast of Rio De Janeiro, Southeastern Brazil

Crustaceana ◽  
2011 ◽  
Vol 84 (12-13) ◽  
pp. 1465-1480 ◽  
Author(s):  
L. P. Jardim ◽  
L. P. Fernandes ◽  
A. P. M. Di Beneditto ◽  
A. C. Silva ◽  
K. A. Keunecke
Keyword(s):  
Rio De Janeiro ◽  
Carapace Length ◽  
Growth Function ◽  
Southeastern Brazil ◽  
Fishery Resource ◽  
Total Length ◽  
Length Relationship ◽  
Von Bertalanffy Growth Function ◽  
Xiphopenaeus Kroyeri ◽  
Average Longevity

AbstractThe objective of this study was to analyse the population growth of the Atlantic seabob shrimp, Xiphopenaeus kroyeri (Heller, 1862) and to establish its recruitment period in the northern part of the State of Rio de Janeiro, southeastern Brazil. Monthly samples of the species were collected over four years (2005-06, 2006-07, 2008-09, and 2009-10) through local artisanal fishery. The size of males and females varied from 25.0 to 134.0 mm and 33.0 to 146.0 mm in total length, 6.0 to 30.0 mm and 5.0 to 33.0 mm in carapace length, and 0.3 to 13.8 g and 0.2 to 17.4 g in weight, respectively. The total weight-length relationship was adjusted with the equations W = 0.000008TL2.9038 (R2 = 0.9446) (males) and W = 0.000002TL3.1719 (R2 = 0.9499) (females). The Von Bertalanffy growth function TLt = TL∞(1 – exp−k(t–t0)) was applied to the data, and the average asymptotic lengths (TL∞) and growth rates (k) were 134.4 ± 6.2 mm and 1.93 ± 0.3 mm for males, and 148.8 ± 3.6 mm and 1.65 ± 0.05 mm for females. The species' average longevity was 2.5 years for males and 2.8 years for females. Males are considered mature when their reach a total length of 66.0 mm and a carapace length of 12.0 mm, while females mature with 109.0 mm total length and 22.0 mm carapace length. In general, the species' recruitment occurred from June to August and from January to May, which partially supports the current legislation to maintain this fishery resource in the region.

Late endoscopic evaluation of the ostium size after external dacryocystorhinostomy

2020 ◽  
pp. 112067212097604
Author(s):  
Reem R Al Huthail ◽  
Yasser H Al-Faky
Keyword(s):  
Chart Review ◽  
Retrospective Chart Review ◽  
Tertiary Hospital ◽  
Nasal Endoscope ◽  
Long Term Follow Up ◽  
Mean Size ◽  
External Dacryocystorhinostomy ◽  
The Mean

Objective: To evaluate the effect of chronicity on the size of the ostium after external dacryocystorhinostomy (DCR) with intubation. Methods: Design: A retrospective chart review of patients who underwent external DCR with intubation over 10 years from January 2003 at a tertiary hospital. All patients were recruited and examined with rigid nasal endoscope. Results: A total number of 66 (85 eyes) patients were included. The mean age at the time of evaluation was 53.1 years with gender distribution of 54 females (81.8 %). The mean duration ±SD between the date of surgery and the date of evaluation was 33.2 ± 33.6 (6–118 months). Our study showed an overall anatomical and functional success of 98.8% and 95.3%, respectively. The mean size of the ostium (±SD) was 23.0 (±15.7) mm2 (ranging from 1 to 80.4 mm2). The size of the ostium was not a significant factor for failure ( p = 0.907). No statistically significant correlation was found between the long-term duration after surgery and the size of the ostium ( R: 0.025, p = 0.157). Conclusions: Nasal endoscopy after DCR is valuable in evaluating the ostium with no observed potential correlation between the long-term follow-up after surgery and the size of the ostium.

An Antarctic shelf population of the deep-sea, Pacific brachiopod Neorhynchia strebeli

1997 ◽  
Vol 77 (2) ◽  
pp. 399-407 ◽  
Author(s):  
David K.A. Barnes ◽  
Lloyd S. Peck
Keyword(s):  
Deep Sea ◽  
Growth Function ◽  
Weddell Sea ◽  
Von Bertalanffy ◽  
Growth Rings ◽  
Von Bertalanffy Growth Function ◽  
Annual Periodicity ◽  
A Site ◽  
The Antarctic ◽  
Order Rhynchonellida

Thirty-five specimens of the articulate brachiopod Neorhynchia strebeli were collected from a site at 814 m in the Weddell Sea. This was only the second species of the order Rhynchonellida to be found in Antarctica. Formerly N. strebeli was known solely from abyssal Pacific Ocean localities. A circumantarctic distribution is suggested in addition to the known deep-sea Pacific range. The specimens of this collection showed considerable commissure variation, suggesting that the previously proposed erection of two subspecies on the basis of this character is erroneous, and emphasises the phenotypic plasticity of some articulate brachiopods. The valve lengths and the number of alpha growth rings in the sample showed a normal distribution and a von Bertalanffy growth function was fitted to the data: Lt = 23 (1-exp[-0·228t]). If the alpha growth rings were of annual periodicity, the ages attained by the Antarctic N. strebeli of 11 y would be substantially lower than those reported for other Weddell Sea brachiopods. The epibiotic communities occurring on the valves of N. strebeli were impoverished, which is characteristic of deep water Antarctic brachiopods. The few specimens collected with their substratum were attached to small pebbles, but the typical attachment substrata may be different.

Abstract P161: Variation in Five-Year Weight Loss Patterns Following Bariatric Surgery by Insurance Status

Circulation ◽  
2017 ◽  
Vol 135 (suppl_1) ◽  
Author(s):  
Erin Takemoto ◽  
Bruce Wolfe ◽  
Corey Nagel ◽  
Janne Boone-Heinonen
Keyword(s):  
Bariatric Surgery ◽  
Weight Loss ◽  
Parameter Estimates ◽  
Similar Amount ◽  
Group Model ◽  
Specific Patient ◽  
Group 6 ◽  
Medicaid Beneficiaries ◽  
Trajectory Models

In the general population, bariatric surgery facilitates sustained weight loss and remission of comorbidities (e.g., CVD). The effectiveness among Medicaid beneficiaries, a population with a disproportionately high burden of obesity, remains unclear. We sought to determine if patterns of weight change following bariatric surgery differed in patients with Medicaid compared to commercial insurance. Data were obtained from the Longitudinal Assessment of Bariatric Surgery, an observational cohort study of adults undergoing bariatric surgery (2006-2009) at one of 6 geographically diverse centers. We used group-based trajectory models (PROC TRAJ, SAS) to identify discrete groups of individuals with similar weight trajectories over 5-years; we considered cubic trajectory models with between 1 and 6 groups. We selected the 6-group model based on Bayesian Information Criteria, visual fit and statistical significance of parameter estimates. We tested demographic predictors against trajectory group membership; Medicaid (n=174) vs. Commercial (n=991) was our primary predictor of interest. Medicaid participants had higher mean weight at baseline compared to the commercially insured (307.9 vs. 291.2 lbs), but lost a similar amount of weight over time (74.8 vs 85.0 lbs). All groups experienced the most weight loss in year 1 (Figure). Group 6 was the heaviest at baseline and began to regain weight after year 1; groups 1-5 continued to lose weight through year 2. Group’s 1 & 2 weight remained stable over 5 years while groups 3-6 began to slowly regain weight. Medicaid beneficiaries were more likely to be in group 4 (OR 3.2, 95% CI: 1.2, 8.6), group 5 (OR 5.7, 95% CI: 2.0, 16.1) and group 6 (OR 7.9, 95% CI: 2.5, 25.1) compared to group 1. Medicaid beneficiaries experience substantial long term weight loss. However, they had higher baseline weight and tended to be in groups with less long-term weight loss compared to the commercially insured. Focusing on tailored interventions to specific patient groups could help maintain weight loss.

Age, Growth and Sex Ratio of the Azorean Rock-Pool Blenny, Parablennius Sanguinolentus Parvicornis

1995 ◽  
Vol 75 (3) ◽  
pp. 751-754 ◽  
Author(s):  
Ricardo Serrão Santos ◽  
Richard D. M. Nash ◽  
Stephen J. Hawkins
Keyword(s):  
Sex Ratio ◽  
Growth Function ◽  
Early Growth ◽  
Reproductive Season ◽  
First Year ◽  
Von Bertalanffy ◽  
Rock Pool ◽  
Total Length ◽  
Von Bertalanffy Growth Function ◽  
One Year

The age and population structure of Parablennius sanguinolentus parvicornis (Valenciennes) (Pisces: Blenniidae) from the Azores have been studied. Total length and weight relationships are given for each sex. Age study was based on otoliths readings. The von Bertalanffy growth function was applied to describe the growth in total length with age. At the end of the first year mean (±SD) total length was significantly different in males (7.1 ±1.5 cm) and females (6.1 ±1.2 cm). One-year-old males participate in reproduction as satellites, whereas females do not. The implications of this in early growth rate of the males is discussed. During the two most important months of the reproductive season (i.e. June and July), the sex ratio was significantly biased towards males, particularly in the larger size classes.

Effects of Long-Term Exposure to Carbaryl (Sevin) on Survival, Growth, and Reproduction of the Fathead Minnow (Pimephales promelas)

1972 ◽  
Vol 29 (5) ◽  
pp. 583-587 ◽  
Author(s):  
A. R. Carlson
Keyword(s):  
Life Cycle ◽  
Fathead Minnow ◽  
Pimephales Promelas ◽  
Threshold Concentration ◽  
Fathead Minnows ◽  
Motile Sperm ◽  
High Concentration ◽  
Toxicant Concentration ◽  
Growth And Reproduction

When fathead minnows (Pimephales promelas) were exposed to five concentrations (0.008–0.68 mg/liter) of the insecticide carbaryl for 9 months and throughout a life cycle, the highest concentration prevented reproduction and decreased survival. At the high concentration, testes contained motile sperm and ovaries were in a flaccid condition and appeared to be in a resorptive state. At the 0.68 mg/liter concentration, carbaryl appeared to contribute to mortality of larvae (produced by unexposed parents) within 30 days of hatching. Survival of young grown in the 0.008 mg/liter concentration was reduced. Since no demonstrable effects were noted for survival, growth, or reproduction at the 0.017, 0.062, and 0.21 mg/liter concentrations, this low survival value is considered not due to carbaryl. The 96-hr median tolerance concentration (TL 50) and the lethal threshold concentration (LTC) for 2-month-old fathead minnows were 9.0 mg/liter. The maximum acceptable toxicant concentration (MATC) for fathead minnows exposed to carbaryl in water with a hardness of 45.2 mg/liter and a pH of 7.5 lies between 0.21 and 0.68 mg/liter. The application factors (MATC/96-hr TL50 and MATC/LTC) both lie between 0.023 and 0.075.

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