Hatch size, somatic growth rate and size-dependent survival in the endangered ploughshare tortoise

The somatic growth rate of 0+ fish of the six major species in Dutch shallow eutrophic lakes, bream (Abramis brama), roach (Rutilus rutilus), pikeperch (Stizostedion lucioperca) (planktivorous and piscivorous), perch (Perca fluviatilis), ruffe (Gymnocephalus cernuus), and smelt (Osmerus eperlanus), was analysed by using a differential equation. This equation models the instantaneous growth rate of a fish as a temperature-dependent power function of body weight. Two of the model parameters were calibrated by optimising the prediction of the growth rate of the fish. Using a new method, which included a parametric bootstrap procedure, confidence limits were estimated for these two calibrated parameters and were used to test the significance of differences between species in growth performance under natural conditions. These tests revealed four groups of species: (A) smelt, (B) roach and bream, (C) ruffe and perch, and (D) piscivorous pikeperch. Growth performance of planktivorous pikeperch mainly overlapped with roach and bream (B) but showed some overlap with ruffe and perch (C). Differences and similarities are explained from the food type (D versus A, B, and C) and the phylogenetic constraints (A versus B versus C) of each species.

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Somatic Growth Effects on the Otolith–Fish Size Relationship in Young Pond-reared Striped Bass, Morone saxatilis

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f89-015 ◽

1989 ◽

Vol 46 (1) ◽

pp. 113-121 ◽

Cited By ~ 163

Author(s):

David H. Secor ◽

John Mark Dean

Keyword(s):

Growth Rate ◽

Striped Bass ◽

Somatic Growth ◽

Morone Saxatilis ◽

Fish Length ◽

Fish Size ◽

Somatic Growth Rate ◽

Size Relationship ◽

Highly Correlated ◽

Otolith Size

Somatic growth rate of pond-reared larval and juvenile striped bass, Morone saxatilis, influenced the relationship between otolith size and fish size. Slower growing groups of individuals had larger and heavier otoliths, relative to fish length, than did faster growing groups. Within each growth group, otolith and fish size were highly correlated. Daily increment formation was validated from 10 to 51 d after hatch. Significant interaction occurred between age and fish size effects on otolith size. We propose that otolith growth occurs by two interacting processes. Otoliths grow daily in an incremental manner which is independent of somatic growth. Growth also proceeds continuously within each daily cycle of increment deposition, probably in some proportion to daily somatic growth. Corollaries to the hypotheses are (1) somatic growth rate can influence the otolith–fish size relationship, (2) intraspecific variation in otolith scaling might be used to predict past differences in somatic growth rate, and (3) there is a biological rationale for the use of otolith size and fish size as predictors in age estimation.

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Morphometry and composition of red drum otoliths: Changes associated with temperature, somatic growth rate, and age

Comparative Biochemistry and Physiology Part A Physiology ◽

10.1016/0300-9629(93)90502-u ◽

1993 ◽

Vol 106 (2) ◽

pp. 209-219 ◽

Cited By ~ 57

Author(s):

Gerald R Hoff ◽

Lee A Fuiman

Keyword(s):

Growth Rate ◽

Somatic Growth ◽

Red Drum ◽

Somatic Growth Rate

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