Morphological features of the bleak Alburnus alburnus (L., 1758) from Międzyodrze

17 meristic and morphometric features were studied in the bleak in the waters of Międzyodrze. Noticeable positive or negative allometry was observed in the growth of head length, horizontal eye diameter, pelvic fins length, body height, and in the distance between pelvic fins and anal fin. In the light of the studied features, the bleak in Międzyodrze places itself in a transitional position between the lake populations and the riverine and estuarine populations

Studies on Psilodraco breviceps Norman,1937 (Pisces, Notothenioidei, Bathydraconidae) from the region of South Georgia

Studies were carried out on morphologic parameters, length-weight relationship, condition, fecundity and food of Psilodraco breviceps - little known benthopelagic fish from the region of South Georgia. Absolute fecundity was within the range 1206-3537. The fish fed mostly on Mysidacea

Growth rate of Iceland and North Sea blue whiting, Micromesistius poutassou (Risso,1810), back-calculated from otoliths

The paper presents blue whiting growth rate back-calculated from otolith broken surface radius. The calculations were corrected using the Rosa Lee method

Studies on growth rate of yellow notothenia, Notothenia gibberifrons Lönnberg, 1905 off South Georgia

The paper demonstrates that scales are not suitable for back readings, due to a poor legibility of their central parts, the peripheral regions being poorly legible in older fish scales as well. One can presume that the scales begin to grow as late as in the second year of life. Most otoliths (sagitta) can be used in back calculations. Based on measurements of radii of various growth zones on the otolith cross-section, mean lengths attained in subsequent years of life were calculated. The von Bertalanffy growth equation parameters were estimated as follows: L∞ = 57.48 cm; K = 1.04; t0 =0.439 yr. The mean length at first maturity was estimated at 37.5 cm, i.e., 65% of L∞

Catches and growth rate of Abramis ballerus (L., 1758) from Lake Dąbie and the Firth of Szczecin

Regular, very intensive fluctuations of the catches of Abramis ballerus occur in 7-8 year cycles. Scale back-calculations (with the method of Rosa Lee) showed that growth of this fish was a little faster in the Firth of Szczecin compared to Lake Dąbie. However, considerable similarity of the parameters in von Bertalanffy′s equation and the distribution of catches suggest that A. ballerus forms a single stock in the two water bodies

Studies on growth rate of yellow notothenia, Notothenia gibberifrons Lönnberg, 1905 off South Georgia

The paper demonstrates that scales are not suitable for back readings, due to a poor legibility of their central parts, the peripheral regions being poorly legible in older fish scales as well. One can presume that the scales begin to grow as late as in the second year of life. Most otoliths (sagitta) can be used in back calculations. Based on measurements of radii of various growth zones on the otolith cross-section, mean lengths attained in subsequent years of life were calculated. The von Bertalanffy growth equation parameters were estimated as follows: L∞ = 57.48 cm; K = 1.04; t0 =0.439 yr. The mean length at first maturity was estimated at 37.5 cm, i.e., 65% of L∞

Studies on juvenile Chaenocephalus aceratus (Lönnberg, 1906) (Pisces, Chaenichthyidae) from off South Georgia

Pelagic trawl catches of krill were found to contain 7.8-11.2 cm long (l.t.) juvenile Chaenocephalus aceratus (Lönnberg, l906) whose morphological characters were studied. The following growth rate is hypothesised to take place during the first five years of life: 10, 20, 27, 34, and 40 cm. The fishes studied were found to feed exclusively on krill, dawn and sunset being the times of the most intensive fish feeding activities

Food and feeding behaviour of Parachaenichthys georgianus (Fischer, 1885) and Parachaenichthys charcoti (Vaillant, 1906) (Pisces, Bathydraconidae)

Studies were made on the content of 278 stomachs of Parachaenichthys georgianus from the region of South Georgia and 30 stomachs of Parachaenichthys charcoti from the region of South Shetlands. Small P. georgianus fed mostly on Mysidacea, medium-sized on shrimps and fishes, large specimens on fishes. P. charcoti fed on fishes, Mysidacea and Euphausiacea

Food and feeding behaviour of eel-cod Muraenolepis sp., (Pisces, Gadiformes, Muraenolepididae) from the region of South Georgia

Amphipoda, Cumacea, and Macrura natantia constituted the basic food component of small eel-cod ( 30 cm) consumed fish, Euphausiacea and Macrura natantia. Mean filling index decreased with increasing depth of catches, while percentage of “empty” stomachs increased

Changes in the blackfin icefish stock structure, Chaenocephalus aceratus (Lönnberg, 1906), Pisces, Notothenioidei, Channichthyidae) off South Georgia within 1975-1992

The paper demonstrates results of the stock monitoring of blackfin icefish in the region of South Georgia in the period of 1988/89-1991/92 as well as summarises seventeen-year period ofobservation (1976/77 -1991/92). The influence of fishing on stock strucrture and supposed reasons of fluctuation ofyear-classes number are discussed