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

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.

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Population Dynamics Of Magellania Fragilis, a Brachiopod Dominating a Mixed-Bottom Macrobenthic Assemblage on the Antarctic Shelf

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315400038200 ◽

1995 ◽

Vol 75 (4) ◽

pp. 857-869 ◽

Cited By ~ 34

Author(s):

T. Brey ◽

L.S. Peck ◽

J. Gutt ◽

S. Hain ◽

W.E. Arntz

Keyword(s):

Growth Function ◽

Von Bertalanffy ◽

Underwater Photography ◽

Annual Productivity ◽

Von Bertalanffy Growth Function ◽

Antarctic Shelf ◽

Size At Age ◽

The Antarctic ◽

Slow Growing ◽

Strong Seasonality

A dense assemblage of the brachiopod Magellania fragilis was sampled by trawl and underwater photography during the expedition ANT IX/3 (1991) of RV ‘Polarstern’ on the shelf of the Lazarev Sea, Antarctica. Mean abundance and biomass estimates for M. fragilis were 26.15 individuals m2 and 1.13 g AFDM m2, respectively. Growth bands visible on the shell were interpreted as annual growth marks caused by the strong seasonality of food input to the benthos and were treated as size-at-age data. The von Bertalanffy growth function Lt (mm) = 51.67 (1 - e0020 (t +1.326))3.828 described these data best. The annual somatic P/B ratio was very low, 0.046 y1, and annual production amounted to 0.052 g AFDM m2 y1 at this particular site. These results indicate that M. fragilis is a comparatively slow-growing species with very low annual productivity.

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

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315400039175 ◽

1995 ◽

Vol 75 (3) ◽

pp. 751-754 ◽

Cited By ~ 18

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.

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Comparing Polynomial and von Bertalanffy Growth Functions for Fitting Tag–Recapture Data

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f94-169 ◽

1994 ◽

Vol 51 (8) ◽

pp. 1689-1691 ◽

Cited By ~ 2

Author(s):

William S. Hearn ◽

George M. Leigh

Keyword(s):

Growth Function ◽

Growth Increment ◽

Bias Reduction ◽

Release Time ◽

Von Bertalanffy ◽

Growth Functions ◽

Straight Line ◽

Von Bertalanffy Growth Function ◽

Multiple Measurements ◽

The One

The properties of polynomial and von Bertalanffy growth functions are compared for analysing data from tag–recapture experiments in which fish are recaptured once. For the quadratic and von Bertalanffy growth functions, explicit formulae are obtained for the expected growth increment in terms of length-at-release, time-at-liberty, and the function parameters. If the least-squares fitting technique is used the von Bertalanffy function fits tag–recapture data with no more bias (probably less) than any other growth function, including polynomial growth functions. A bias-reduction technique for fitting the von Bertalanffy growth function to tag–recapture data is not applicable to other growth functions. We conclude that, apart from the straight line, the von Bertalanffy growth function is the one with the most desirable mathematical and statistical properties for fitting to tag–recapture data. The matter of the function that best characterises the way a specific fish species grows can be adequately addressed only by analyses of multiple measurements of individual fish.

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Population dynamics of Sterechinus antarcticus (Echinodermata: Echinoidea) on the Weddell Sea shelf and slope, Antarctica

Antarctic Science ◽

10.1017/s0954102091000305 ◽

1991 ◽

Vol 3 (3) ◽

pp. 251-256 ◽

Cited By ~ 28

Author(s):

Thomas Brey

Keyword(s):

Reproductive Output ◽

Specific Growth ◽

Cold Water ◽

Growth Function ◽

Weddell Sea ◽

Average Value ◽

Size Frequency ◽

Von Bertalanffy Growth Function ◽

Somatic Production ◽

Rate Method

Sterechinus antarcticus inhabits the shelf and the slope of the Weddell Sea and is the predominant echinoid between 450 and 1200 m. Growth lines visible in the half pyramids of the Aristotle's lantern were interpreted as annual growth marks. A Von Bertalanffy growth function was fitted to age-diameter data of 217 specimens (D∞ = 82.4 mm, K = 0.017 y−1, t0 = 1.633 y). Based on 92 trawl samples, a representative size-frequency distriution of S. antarcticus was established. From the growth curve, the size-frequency sample and diameter - weight regressions, mortality and somatic productivity of S. antarcticus were calculated by a size-converted catch curve and the weight specific growth rate method. Gonadal productivity was estimated by an average value for reproductive output of cold water echinoderms. Mortality rate Z as'well as somatic P/B ratio amounted to 0.07 y−1. Annual somatic production was estimated as 0.3 mg m−2y−1, and annual gonadal production as 0.25 mg m−2 y−1 between 100 and 1200 m (0.6 and 0.5 mg m−2 y−1 between 450 and 1200 m).

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A new model accounting for seasonal cessation of growth in fishes

Marine and Freshwater Research ◽

10.1071/mf9921151 ◽

1992 ◽

Vol 43 (5) ◽

pp. 1151 ◽

Cited By ~ 39

Author(s):

S Pauly ◽

M Soriano-Bartz ◽

J Moreau ◽

A Jarre-Teichmann

Keyword(s):

Salmo Salar ◽

Growth Function ◽

Sine Wave ◽

Smooth Transition ◽

Von Bertalanffy ◽

New Model ◽

Von Bertalanffy Growth Function ◽

Zero Growth ◽

Key Features ◽

Summer Growth

A modified version of the von Bertalanffy growth function (VBGF) is proposed in which a sine wave modifies a standard version of the VBGF, enabling a smooth transition between rapid summer growth and a variable period of zero growth (in length) during winter or during the dry season for aestivating fishes. The key features of a nonlinear routine for fitting this new model are also presented, with emphasis on the estimation of the period of zero growth. Application examples, to Salmo salar and Trisopterus esmarkii, are presented.

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