caa a22 4500 465811051 CHVBK 20180323112116.0 cr unu---uuuuu 170327e19900601xx s 000 0 eng 10.1007/BF02123439 doi (NATIONALLICENCE)springer-10.1007/BF02123439 Ueno Masahiro Fisheries Research Station, Kyoto University, Nagahama, 625, Maizuru, Japan aut Relation between mean and variance in catch numbers of fish egg and larva [Elektronische Daten] [Masahiro Ueno] In each of six areas with various horizontal scale from 0.4 to 15.6 nautical miles, many surveys with vertical net hauls are made for sampling fish eggs and larvae. Though values ofC A are widely spread in each area, the variances 2 and the meanm of catch numbers calculated from each survey follow approximately the relation from a Poisson mixture model (PMM). $$s^2 = m + C_A m^2 $$ . WhereC A (Kuno's aggegation index) is generally an index of magnitude of variability in catch numbers on the surveyed space (time or time-space). Moreover, this relation is equivalent to the relation between the variance and the mean in a negative binomial distribution model (NBM). However, NBM is a special case in the PMM. The minimum value ofC A generally depends on the horizontal scale of each area. Large values ofC A, however, are not so rare. In order to explain the large values ofC A, changes ofC A value are estimated on a simple model area that consists of two sub-areas: in one, some planktonic organisms are abundant; poor in the other. TheC A values increase with increasing area ratio of the poor sub-area to the whole area. In a widely spread area such as planktonic survey occupied, the change ofC A value mainly indicates the change of the area ratio as a result. The Taylor's power law, a famous relation between the variance and the mean in catch numbers, has a conflict with the relation from the PMM. Within a short range of the mean, the relation is nearly a straight line on log scale. The law represented with a strictly straight line was derived mostly from data with short-ranged means, and hence the law is inadequate. the Oceanographical Society of Japan, 1989 Journal of the Oceanographical Society of Japan Kluwer Academic Publishers 46/3(1990-06-01), 125-134 0029-8131 46:3<125 1990 46 10872 https://doi.org/10.1007/BF02123439 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF02123439 text/html Onlinezugriff via DOI NATIONALLICENCE 100 1- Ueno Masahiro Fisheries Research Station, Kyoto University, Nagahama, 625, Maizuru, Japan aut NATIONALLICENCE 773 0- Journal of the Oceanographical Society of Japan Kluwer Academic Publishers 46/3(1990-06-01), 125-134 0029-8131 46:3<125 1990 46 10872 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer