Crimea: sporadic findings were made only on the southern spit of coastal salt Lake
Donuzlav. In Kazachaya bay of Sevastopol polychaetes P. kefersteini were seen
nearly year round whereas in Sevastopol Bay not a single one has been detected for
the 13-month period of observations (Kopiy et al. 2010; Kopiy 2011).
Though population of P. kefersteini includes polychaetes of different body sizes,
75% of their total abundance in the water-edge zone was due to the worms longer
than 20 mm. The share of large polychaetes decreased to 21% at 1-m depth and
drastically dropped to 1% at 1.5-m depth (Fig. 24.6).
In different seasons of the year spatial distribution of P. kefersteini by depths
was different (Fig. 24.7).
150
Mean density, ind.m 2
100
50
0
1
2
3
4
5
Number of segments
depth 1 m
depth 1.5 m
6
7
8
9 10 11 12 13
Fig. 24.4 Size ratio of juvenile polychaetes P. kefersteini collected at 1-m and at 1.5-m depths
2,5
2
1,5
1
Lenght of polychaetes, mm
0,5
0
0
2
4
6
8
10
12
14
Number of segments
Fig. 24.5 Correlation between the length and the number of segments of P. kefersteini
24 Some Aspects of the Biology and the Present State of the Population. . .
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