Plasticity in life history traits of the nativeProterorhinus semilunarissuggests high adaptive capacity in its invasive range

Abstract

Invasion risk assessments are reliant on ecological data that assist the predictions of whether an introduced species will adapt to novel conditions. Data from the native range of potential invaders can thus assist these assessments. Here, the growth and reproductive characteristics of the Western tubenose goby Proterorhinus semilunaris, a Ponto-Caspian gobiid, were assessed in three natural lakes in their native range, as there are few extant data on these traits. Across the three lakes, the gobies were found in varying abundances. Sex ratios varied, with females significantly outnumbering males in only one lake, with equal sex ratios in the other lakes. The fish always showed a positive allometric growth, but had high variability in their somatic growth rates and relative body conditions between the lakes. Scale ageing revealed all populations comprised of individuals to four years old, with one lake having individuals to 5 years old. Reproductive characteristics, including size at maturity, gonado-somatic index and fecundity, did not differ significantly between the lakes. These data suggest that plasticity in aspects of their life history traits provides P. semilunaris with considerable adaptive capacity following their introduction into novel conditions.

Plasticity in the feeding ecology of native Ponto‐Caspian gobies suggests establishment success in their nonnative range

“…In the present study, gut content analysis of P. semilunaris and N. fluviatilis from some natural lakes within both species’ native range revealed overall similarities in prey consumption, with dietary overlap evident during the spawning period (Karakuş et al, ; Top et al, ). Previous studies on the diet of N. fluviatilis consistently indicate that this gobiid consumes a broad spectrum of prey items, which in its nonnative range consist mainly of macroinvertebrates (i.e., Amphipoda, Bivalvia, Chironomidae, Odonata, and Trichoptera; Adámek et al, ; Grabowska et al, ; Kakareko et al, ; Piria et al, ), and in its native range of Bivalvia, Chironomidae and other insects, Crustacea, Oligochaeta, Polychaeta, Mollusca, as well as fish eggs and small fish (i.e., Black Sea and Sea of Azov basins; Abdoli, Rahmani, & Rasooli, ; Gaygusuz et al, ; Pinchuk et al, ; Smirnov, ).…”

“…Using a Euclidean distance measure following normalization of the data, these were used to obtain a distance matrix, which was subjected to 9,999 permutations of the raw data and tested for significance, with a posteriori pairwise comparisons evaluated at α = 0.10 for heuristic purposes (Kline, ). To assess ontogenetic variation in feeding, both species were divided into two groups (adult and juvenile) based on size at maturity for P. semilunaris (Top, Karakuş, Tepeköy, Britton, & Tarkan, ) and N. fluviatilis (Karakuş et al, ).…”

Plasticity in habitat use of two native Ponto-Caspian gobies, Proterorhinus semilunaris and Neogobius fluviatilis: implications for invasive populations

“…This suggests some adaptive capacity of both species regarding habitat utilization (e.g. KarakuÕ et al, 2018;Top et al, 2018). The results here are congruent with this, with both native gobiids revealing high variability in their habitat use, with this apparent between seasons and lakes.…”

“…This plasticity, in conjunction with other traits, including a generalist life history, plasticity in growth and capability of shifting reproductive features, is likely to confer considerable advantages in their establishment and invasion (e.g. Tarkan et al, 2018;KarakuÕ et al, 2018;Top et al, 2018). There was more evidence of some specialisation in the habitat uses of N. fluviatilis (e.g.…”

“…For P. semilunaris and N. fluviatilis, ecological knowledge on their populations in their native range is limited, but has recently increased in relation to the expression of their life history traits and their trophic relationships with other species KarakuÕ et al, 2018;Top et al, 2018). There remain, however, considerable knowledge gaps in the habitat use of both native P. semilunaris and N. fluviatilis, as well as other common gobiids, such as round goby Neogobius melanostomus (Kornis et al, 2012).…”