0000000000296256
AUTHOR
Sergio Ragonese
showing 7 related works from this author
Reproductive features of the deep-water rose shrimp, Parapenaeus longirostris (Crustacea: Penaeidae), in the Strait of Sicily
2010
The deep‑water rose shrimp, Parapenaeus longirostris (Lucas, 1846), is one of the most valuable and heavily exploited demersal species of the Mediterranean bottom trawl fisheries. The basic life traits of this shrimp, in particular its reproductive aspects, are regularly monitored during experimental trawl surveys carried out in the Mediterranean Sea. Gonadic condition and maturity status for estimating the size at onset of sexual maturity are commonly assessed in females, using macroscopic color scales, histologically validated only in a few geographical areas. In this study, histological analyses were performed on rose shrimps collected from a trawl survey carried out in the Strait of Sic…
Trawl mesh selectivity and body engagement pattern in the red shrimpAristaeomorpha foliacea(Risso, 1827) (Crustacea: Decapoda)
1998
The paper presents selectivity data and utilizes an elliptic surface index (maximum height and width of the folded body), in order to explain the selectivity differences between sexes and to investigate the body engagement pattern of the red shrimp Aristaeomorpha foliacea. The results show that males are retained more, with significant differences, and demonstrates a previously unknown morphological difference between sexes (folded males are significantly higher than females of the same carapace length, while the latter are larger, but not significantly, than males of similar size). Nevertheless, in practice the overall escapement rate should not change dramatically with sex, since the resu…
A century of fishery data documenting the collapse of smooth-hounds (Mustelusspp.) in the Mediterranean Sea
2017
Conservation and management of shark populations is increasingly becoming important in many marine regions, since there is a growing body of evidence showing that several species are threatened and continuing to decline because of unregulated fishing. Quantifying the extent of sharks' decline, the risk of species extinction, and the consequences for marine ecosystems have been challenging and controversial, mostly due to data limitations. In this study, more than one century of multiple-sources of bibliographic records on presence and frequency of occurrence of three species of commercial sharks, the smooth-hounds Mustelus spp., in the Mediterranean Sea were compiled and analysed. Generaliz…
Evidence of lipofuscin accumulation in the deep-water red shrimp Aristaeomorpha foliacea (Risso, 1827)
2008
Lipofuscin, a non-degradable, degenerative fluorescent pigment which accumulates in post-mitotic cells, represents a promising method for ageing marine crustaceans. The presence and accumulation of lipofuscin has been studied in the deep-water red shrimp Aristaeomorpha foliacea (Risso, 1827) to assess its use as a tool for ageing larger (i.e., older) specimens and thus improve knowledge of the growth and longevity of this species. Specimens, gathered during experimental trawl surveys carried out in the Strait of Sicily (Mediterranean Sea), were stored directly on-board in 10% buffered formaldehyde solution; their brain was thereafter removed, prepared with various current histological techn…
Distribution and biology of the Blackmouth catshark Galeus melastomus in the Strait of Sicily (Central Mediterranean Sea)
2009
The Blackmouth catshark, Galeus melastomus, Rafinesque, 1810 (Carcharhiniformes; Scyliorhinidae), is a common, although at present discarded, by- catch of the bottom trawl fisheries in the Strait of Sicily. Given its ecological interest, data gathered in experimental bottom trawl surveys were analysed in order to describe its distribution and main biological traits. The Blackmouth catshark was sampled almost exclusively on the upper slope (200-800), showing the highest frequency of occurrence (69-100%), biomass (BI; 10-85 kg*km-2) and density (DI; 54-506 N*km-2) indexes in the deeper (501-800m) grounds. Individual size (total length, TL, mm) were between 70-590 and 90-510 in females and mal…
Otolith-based age and growth of the Lessepsian species Fistularia commersonii (Osteichtyes: Fistulariidae) in South of Sicily (Central Mediterranean …
2016
During spring–summer 2013, 23 specimens of the Lessepsian Fistularia commersonii Rüppell, 1838 were studied through occasional catches by artisanal and coastal trawler fisheries in the South of Sicily (Mediterranean Sea). The total lengths (TL, cm, without filament) and weight (W, g) ranged between 69.0 and 104.0 cm and 155 and 798 g, respectively. The estimated sex-combined parameters of the length–weight relationship (k = 9*10–9; b = 3.6) suggested a positive allometry. All pairs of sagittae were examined under a stereomicroscope and the age estimated by counting the complete translucent zones, both as whole and thin sections, with ages from 3 to 5 years. Growth parameters (von Bertalanff…
Physiological stress indicators in the plasma of Scyliorhinus canicula captured by botto trawling at two depths.
2022
The quantification of capture-related physiological stress is an important factor when assessing the potential for post-release survival in sharks that are incidentally captured. In the absence of these biological data and when the post-release fate is unknown, effective management plans cannot be formulated and may lead to highly susceptible shark populations being overfished. Here, we measured the levels of lactate, glucose, alanine amino transferase (ALT), aspartate amino transferase (AST), Ca2+, Na+ K+,Cl - Mg 2+ and Pi in the plasma of mature and immature lesser spotted dogfish (Scyliorhinus canicula, herein dogfish) which were incidentally captured at two depths (shallow: 50-200 m, an…