| 1. |
- Corsini-Foka, Maria, et al.
(author)
-
On the finding of the Indo-Pacific fish Scomberomorus commerson in Rhodes (Greece)
- 2008
-
In: Mediterranean Marine Science. ; 9:1, s. 167-171
-
Journal article (peer-reviewed)abstract
- The occurrence of the Indo-Pacific fish Scomberomorus commerson was observed for the first time in the Hellenic waters of the SE Aegean Sea during the spring 2008. The record may represent a first indication of a population expansion of this alien species along the southern coasts of the Aegean Sea.
|
|
| 2. |
|
|
| 3. |
|
|
| 4. |
- Kalogirou, Stefan, 1981, et al.
(author)
-
Diversity, structure and function of fish assemblages associated with Posidonia oceanica beds in an area of the eastern Mediterranean Sea and the role of non-indigenous species
- 2010
-
In: Journal of Fish Biology. - 0022-1112. ; 77:10, s. 2338-2357
-
Journal article (peer-reviewed)abstract
- Temporal and spatial variation in density, biomass and body size of littoral fish species associated with nearshore Posidonia oceanica meadows was studied over an annual cycle in an area of the eastern Mediterranean Sea. A total of 109 350 littoral fishes were collected, belonging to 34 families and 88 species. Density of fishes peaked during the summer due to high numbers of juveniles. Season was a significant factor determining density, although number of species and biomass did not show any obvious seasonal pattern. Throughout the study, schooling planktivorous fish species such as the picarel Spicara smaris, the bogue Boops boops and the damselfish Chromis chromis were dominant, both in terms of density (80%) and biomass (70%). Temporal variation in density and body size of fishes was used to assess the seasonal and ontogenetic habitat use of each species, with their affinity to seagrass assessed by comparing their respective distribution on sand. Four functional guilds were created (juvenile migrants, seagrass residents, seasonal migrants and occasional visitors) to describe the habitat use of P. oceanica meadows by each species. Several species associated with P. oceanica meadows used this habitat mainly as juveniles during summer, although many others were present concurrently as adults and as juveniles. Among the species encountered, 11 were non-indigenous of Indo-Pacific origin, of which three used seagrasses mainly as juveniles and four as residents. The non-indigenous silverstripe blaasop Lagocephalus sceleratus ranked among the 10 most dominant species in terms of biomass (2%) and was classified as a seagrass resident.
|
|
| 5. |
- Kalogirou, Stefan, 1981, et al.
(author)
-
Feeding ecology of indigenous and non-indigenous fish species within the family Sphyraenidae
- 2012
-
In: Journal of Fish Biology. - : Wiley. - 0022-1112 .- 1095-8649. ; 80:7, s. 2528-2548
-
Journal article (peer-reviewed)abstract
- The feeding ecology of two common indigenous (Sphyraena viridensis and Sphyraena sphyraena) and one abundant non-indigenous sphyraenid species, Sphyraena chrysotaenia, of Indo-Pacific Ocean origin, was investigated in an area of the eastern Mediterranean Sea. The stomach contents of 738 individuals of varying size, collected during the period December 2008 to August 2009, were examined. The dietary analyses revealed that all three species were specialized piscivores with a diet consisting of >90% fish, both by number and mass. Concurrent sampling of the fish assemblage made it possible to calculate selectivity as well as diet breadth and overlap of these strict piscivores. Even though several prey species were found in the stomachs of the three predators examined, selectivity towards Atherina boyeri was highly significant. For all species examined, >70% of the diet by mass was made up by three indigenous species of commercial value: Spicara smaris, Boops boops and A. boyeri. Diet breadth and size of prey increased with increasing body size for all predators. With increased body size, the diet overlap between indigenous and non-indigenous species decreased. This could be attributed to increased diet breadth and the specific life-history characteristics of indigenous species developing into larger individuals. During winter, the condition factor of the non-indigenous species was significantly lower than that of the indigenous, indicating that winter conditions in the Mediterranean Sea may limit its further expansion north and westward. With this study, the gap in knowledge of the feeding preferences of the most abundant piscivorous species found in coastal areas of the study region is filled. Additionally, the results indicate that non-indigenous species familial affiliation to indigenous ones does not facilitate invasion success.
|
|
| 6. |
- Kalogirou, Stefan, 1981
(author)
-
First record of the non-indigenous fangtooth moray Enchelycore anatina
- 2010
-
In: Mediterranean Marine Science. - 1108-393X. ; 11:2, s. 357-360
-
Journal article (other academic/artistic)abstract
- One specimen of the non-indigenous fangtooth moray Enchelycore anatina of tropical Atlantic origin was for the first time found in an area of the south -eastern Aegean Sea. This record might not indicate a recent establishment in the area and is hereby considered an overlooked species, attributed to lack of fish studies on rocky bottoms.
|
|
| 7. |
- Kalogirou, Stefan, 1981
(author)
-
Fish Community Structure and the Role of Non-Indigenous Species Associated to Seagrass Ecosystems of Eastern Mediterranean
- 2010
-
Licentiate thesis (other academic/artistic)abstract
- Temporal and spatial variation in density, biomass and body size of littoral fish species associated with near shore Posidonia oceanica meadows were studied throughout an annual cycle in an area of eastern Mediterranean. Approximately 109350 littoral fish were collected, belonging to 34 families and 88 species. Density of fish peaked during the summer due to high densities of juveniles. Season was found to be an important factor in discriminating density of species, while number of species and biomass did not show any obvious seasonal pattern. Temporal variations in density and body size of fish were used to assess the seasonal and ontogenetic habitat use of each species and the affinity to seagrass was assessed in a comparison with each species distribution on sand. Four functional guilds were created to describe the habitat use of P. oceanica meadows for each species encountered including juvenile migrants, seagrass residents, seasonal migrants and occasional visitors. Several species associated with P. oceanica meadows mainly used this habitat for spending their juvenile stages during summer although many species were found to use this habitat both as adults and juveniles at the same time. Among the species encountered, eleven were found to be non indigenous of Indo-Pacific origin, three of them using segrasses mainly as juveniles, and four as residents. In an earlier study the composition of the diet of the Indo-Pacific cornetfish Fistularia commersonii from the SE Aegean Sea was described. Dietary comparisons were made reflecting the relationship between diet composition, time of year, and fish size. Correlation between predator length and prey length was significant. The diet of the blue cornetfish consists of 96% by number and 99.95% by weight of fish. Size classification and habitat of prey groups (benthic, supra-benthic, and pelagic) showed that with increased body length the blue cornetfish extended its diet to larger prey and more generalist feeding.
|
|
| 8. |
- Kalogirou, Stefan, 1981, et al.
(author)
-
Non-indigenous species in Mediterranean fish assemblages: Contrasting feeding guilds of Posidonia oceanica meadows and sandy habitats
- 2012
-
In: Estuarine, Coastal and Shelf Science. - : Elsevier BV. - 0272-7714 .- 1096-0015. ; 96:1, s. 209-218
-
Journal article (peer-reviewed)abstract
- Quantitative sampling in combination with classification of fish species into six major feeding guilds revealed the position and contribution of non-indigenous species (NIS) in the food web of Posidonia oceanica and sandy habitats in an area of the eastern Mediterranean. In P. oceanica beds and on sandy bottoms 10 and five species, respectively, were non-indigenous fish of Indo-Pacific origin. The proportional contribution of NIS individuals on P. oceanica beds was lower than that of sandy bottoms (12.7 vs. 20.4%) a pattern that also followed for biomass (13.6 vs. 23.4%), indicating that low diverse systems may be more liable to introductions than species-rich communities. The two habitats had similar fish feeding guilds, but the biomass contribution from NIS varied within each guild, indicating different degrees of impact on the available resources. This study showed that only few non-indigenous fish species contributed to the differences in biomass between habitats. No support could be found in postulating that taxonomic affiliation could predict invasion success. Size was considered highly important due to habitat shift of species with increased size. Two of the aspects considered in this study, the chance of establishing vs. the chance of being very dominant will depend upon competitive abilities strongly coupled to size and grounds for habitat shift. However, success of establishment will also depend on appropriate food resources in the recipient community as well as competitive abilities and level of competition in the food web within habitats
|
|
