Jan 16, 2023Open Access
This paper reviews two studies discussing density-dependent growth using Japanese sardine data. However, the results and interpretation of these two papers indicate inconsistencies and conflict with each other. This study shows that the length of sardines in year t can be explained by the values of the three-year moving average of reproductive success in year t - 3. This indicates that the existing density-dependent growth of sardines is questionable and that environmental conditions determine t...
Jan 11, 2022Open Access
The original online version of this article (Sakuramoto, K. (2021) Reproductive Success in Fish Stocks Can Be Reproduced by Environmental Factors Alone. Open Access Library Journal, 8: e7636.
https://doi.org/10.4236/oalib.1107636) unfortunately contains some mistakes. The author wishes to correct the errors in the following version:
Dec 22, 2021Open Access
A model that forecasts future values of the reproductive success (RPS) for the Pacific stock of Splendid alfonsino (Beryx splendens) using environmental factors is described. The monthly Arctic oscillation index and Pacific decadal oscillation were used as the environmental factors. The RPS from 1999 to 2019 was reproduced and that from 2020 to 2024 was forecasted. The results were as follows: The fitness between the observed and reproduced RPS coincided well. The average RPS from 1999 to 2019 w...
Jul 23, 2021Open Access
This study showed that reproductive successes (RPS) in fish stocks could be reproduced using only environmental factors. As the environmental factors, the monthly Arctic oscillation index and Pacific decadal oscillation were used. The RPS of 12 stocks harvested around Japan were reproduced. The results were as follows: the fitness between observed and reproduced RPS, and the number of the independent variables necessary for reproducing the RPS differed by stock. However, the fluctuations of RPS ...
Mar 16, 2021Open Access
Loop-shaped trajectories are commonly observed in the stock-recruitment relationship (SRR). A mechanism that explains why the loops emerge in SRR has been proposed, and the aim of this study was to validate this mechanism using 62 stocks that live in the waters around Japan, the Northwest Atlantic Fisheries Organization area, and elsewhere. We discuss the relationship between the age at maturity and the slope of the regression line adapted for the SRR data. Further, we discuss whether or not the...
Jan 16, 2020Open Access
This work studied the effect of fish pond wastewater, proximate and mineral analyses of the fish feeds from commercial fish ponds on receiving soils in the southern Guinea Savanna ecological zone of Minna, Nigeria. The study con-ducted during the dry seasons of the years 2015 and 2016 between January and May. Four sets of soil samples were collected at varying distances from the various fish ponds an
May 20, 2019Open Access
This paper presents data from shore-based and limited boat observations of the seasonal distributions of humpback whales in waters adjacent to the Chukotka Peninsula from 1994 and 2012. Under favourable ice conditions, humpback whales were spotted off the coast of the Chukotka Peninsula as early as the end of May. During the summer, humpback whales remained dispersed in the coastal waters of t
Mar 15, 2018Open Access
In silico analysis can be useful to infer about the
horizontal gene transfer (HGT) as well as to deduce about the evolutionary
relations of catabolic genes. In this study, we performed the analysis of two
housekeeping genes (fabD and rpoD) and two catabolic gene
Mar 05, 2018Open Access
epiphytic microbial communities of seagrass (Cymodocea rotundata and Thalassia testudinum) along with sediments and seawater of the seagrass
ecosystem of Andaman
Feb 28, 2018Open Access
I propose a mechanism that controls the
stock-recruitment relationship (SRR), which should replace traditional SRR
models. The difference between the traditional SRR models and the model
proposed herein is whether or not a density-dependent effect is assumed. The
new mechanism elucidates the following: 1) why clockwise loops or anticlockwise
loops are commonly observed in an actual SRR, and 2) the age at maturity (not a