Macrourid fish are abundantly found on the continental slope of the Ionian Sea (eastern Central Mediterranean), but the knowledge on their biology is still rather scanty. The reproductive stragegy of Hymenocephalus italicus, Nezumja sclerorhynchus and Coelorhynchus coelorhynchus was studied through data collected during 8 seasonal trawl surveys carried out between April 1996 and March 1998. Ripe females of H. italicus and N. sclerorhynchus were found all year round, with a small increase during summer and autumn in the former and without any seasonal component in the latter. Few ripe females of C. coelorhynchus were collected over the study period, with the exception of October 1996 when an increase was recorded, indicating that autumn could be included in the breeding season of this grenadier. The many different sizes of eggs and postovulatory follicles found in the ovaries indicate that all 3 species reproduce serially as multiple batch spawners. Maximum egg sizes were 1.5 mm in H. italicus and N. sclerorhynchus and 1.6 mm in C. coelorhynchus. The h~ghest gonadosomatic index values were found in H. italicus, and the lowest in C. c'oelorhynchus. All 3 species seem to delay reproduction. The size at first maturity (50% of the population) was 27 mm pre-anal length in H. italicus, 37 mm in N. sclerorhj/nchus and 61 mm in C. coelorhynchus. Aseasonal continuous spawning can be assumed for N. sclerorhynchus while the low frequency of the early maturity stages in H. italicus makes it difficult to state whether or not this macrourid spawns throughout the year without a seasonal component. Further study is necessary to define the reproductive cycle of C. coelorh ynch us.

Specimens of Phycis blennoides were collected in the Ionian Sea by means of trawl surveys from August 1993 to July 1995. Ripe females and mature males were caught during November through January and between August and March, respectively. Recruitment, represented by individuals of 6-8 cm total length modal group, took place during March at depths between 200 and 600 m. Modal progression analysis of juveniles indicated a growth rate of about 1 cm/month during the first year. Otoliths were examined from juveniles. A transition zone was generally observed in the otolith nucleus. Females and males had mean size of 15.6 and 15.4 cm TL, respectively, during the first year, while during the 2nd year individuals attained a mean size of 20.7 and 20.3 cm TL, respectively. The fastest growth occurred during the spring and summer seasons.

The fish Hoplostethus mediterraneus is a bycatch of the deep-water trawling in the northwestern Ionian Sea. Data on its life history traits were collected during twelve trawl surveys carried out at two month intervals, between August 1993 and July 1995.A vertical distribution according to size was observed for this species. The year's young were recruited mainly during the spring-summer period. Sex-ratio changed by size with females larger than males. Mature specimens were found mainly between May and November with a reproductive peak during late summer.Seasonal growth was detected in the otoliths; the maximum ages of 11 and 10 y were observed in females and males respectively. Von Bertalanffy growth parameters for the whole population were: L 3C =287-08 mm, k=0-127 y, t o =-2-131. No significant differences were detected between the growth patterns of the sexes. Overall growth perfomance depicted through size-distribution analysis was not significantly different from that obtained by otolith reading.Estimates of natural mortality rate for the whole population ranged from 0-14 to 0-20. Population structure, growth pattern, age at first maturity and low natural mortality rate indicate a life history mainly constituted by k-strategy characters and regulated by density-dependent mechanisms.

Hymenocephalus italicus, Nezumia sclerorhynchus and Coelorhynchus coelorhynchus were found in 80, 75 and 69% of trawl hauls carried out between 250 and 750 m on the upper slope of the Ionian Sea. The abundance of H. italicus and N. sclerorhynchus increased with depth while in C. coelorhynchus the highest densities were observed in the uppermost 500 m. In all three grenadiers the average size increased with depth. The populations had a multimodal sizefrequency distribution. In H. italicus adults were generally more represented in the population and the abundance of juveniles varied with seasons. In N. sclerorhynchus and mostly in C. coelorhynchus the bulk of the population was generally made up of small individuals the year round. In N. sclerorhynchus a seasonal pattern was shown in the depth distribution of juveniles. The sex ratio was in favour of females in larger specimens and in each bathymetric stratum. Seasonal growth was detected in the otoliths of the three species. Maximum ages were around 9 years in H. italicus and N. sclerorhynchus; 8 years in C. coelorhynchus. Although some differences have been detected in the population ecology of the three species, they are characterized by a prolonged recruitment during the year, slow growth, longevity and delayed maturity. 2000 The Fisheries Society of the British Isles

Aspects of reproduction of macrourid fish in the north‐western Ionian Sea are reported. Data were collected during 12 trawl surveys carried out between 1993 and 1995. Mature and running ripe females of Coelorhynchus coelorhynchus, Hymenocephalus italiens and Nezumia sclerorhynchus were found all year round. Mature females of Trachyrhynchus trachyrhynchus were found mainly in August.