Seasonal fluctuations of some biological traits of the invader <i>Caprella scaura</i> (Crustacea: Amphipoda: Caprellidae) in the Mar Piccolo of Taranto (Ionian Sea, southern Italy)

Abstract

SUMMARY:Caprella scaura is an epifaunal amphipod crustacean that originates in the western Indian Ocean and has spread throughout the world, but very little is known about fundamental aspects of its biology. This paper is the first presentation of its life history traits in an invaded region. The study was conducted in the Mar Piccolo basin (southern Italy, Ionian Sea), over a one-year period. All biological parameters showed a strong seasonal pattern, breeding peaked twice during the year and the number of eggs in the ventral brood pouch ranged from 5 to 72. The sex ratio was generally close to 1:1. A strong correlation between total length of ovigerous females and number of eggs was observed. The mean length of both mature males and mature females was 10.63 and 7.70 mm, respectively. The results of this study showed that the population dynamics of this species was not dissimilar to that of other caprellids or marine epifaunal Crustacea. This caprellid has given rise to a stable population in the Mar Piccolo; it was present all year round in the study area but its density suggests that it is not yet a strong invader.

Population biology of sympatric species of Caprella (Amphipoda: Caprellidae) in a tropical algal bed

“…The maximum size of the caprellids in our study was considerably smaller than that of other populations. Caprella scaura males of a population in southern Italy (Prato et al 2013) reached 23 mm and in the present study they reached only 12.96 mm. Caprella equilibra males from the northern Adriatic Sea (Sconfietti and Luparia 1995) reached 19 mm, while in the studied area the maximum male size was 12.53 mm.…”

“…In the last two decades, some studies involving caprellid diet (Guerra-García and Figueroa 2009) and distribution patterns (González et al 2008, Vázquez-Luis et al 2009) have been performed, but reproductive and population studies of these crustaceans are still few in number (Bynum 1978, Sconfietti and Lupari 1995, Prato et al 2013, particularly in tropical areas , De Paula et al 2016. Knowledge on population attributes is important because they provide information about ecological stability of populations, including temporal variation in abundance, size structure, birth rates and mortality (Hutchinson 1981, Santos et al 1995.…”

Spreading and Establishment of the Non Indigenous Species Caprella scaura (Amphipoda: Caprellidae) in the Central Region of the Aegean Sea (Eastern Mediterranean Sea)

“…Due to the large number of individuals, a representative subsample for each sampling was created by randomly selecting 50 males, 50 females and 15 juveniles in order to perform a balanced statistical design for length comparisons (i.e., between sexes, depth level and among samplings) as well as to construct the length-frequency distribution (LFD) of the population from each sampling [8]. Digital photos of specimens were taken using an Olympus SZX-9 stereomicroscope, and each individual was measured from the anterior margin of the head to the posterior margin of the telson to the nearest 0.1 mm [16], using the image processing and analysis software ImageJ (v. 1.53e National Institute of Mental Health, Bethesda, MD, USA) [45].…”

Population and reproductive biology of two caprellid species (Crustacea: Amphipoda) associated to Sargassum cymosum (Phaeophyta: Fucales) on the southeast coast of Brazil

“…Most information published on caprellids is related to taxonomical papers, including descriptions of new taxa (e.g., Guerra-García, 2003) and inventory of species (e.g., De-La-Ossa-Carretero et al, 2010). Studies involving population and reproductive biology are still particularly scarce (Prato et al, 2013;De Paula et al, 2016;Nuñez-Velazquez et al, 2017). Population structure data are particularly important providing basic information about ecological stability of populations, including seasonal abundance, population size structure, birth rates and mortality (Hutchinson, 1981;Santos et al, 1995).…”