Eglė Jakubavičiūtė

Nature Research Centre · Institute of Ecology

The northern pike (Esox lucius) is an iconic predatory fish species of significant recreational value and ecological role in the Baltic Sea. Some earlier studies indicate local declines of pike in the region, but a thorough spatial evaluation of regional population trends of pike in the Baltic Sea is lacking. In this study, we collate data from 59...

Pikeperch (Sander lucioperca) is a European fresh and brackish water piscivorous fish, important as both a key predator and a valuable commercial and recreational fisheries species. There are concerns that some stocks are depleted due to overfishing and environmental changes. We review data collection and population assessments currently used for n...

The temperature-size rule is one of the universal rules in ecology and states that ectotherms in warmer waters will grow faster as juveniles, mature at smaller sizes and younger ages, and reach smaller maximum body sizes. Many models have unsuccessfully attempted to reproduce temperature-size rule-consistent life histories by using two-term (anabol...

It is often assumed that recreational fishing has negligible influences on fish stocks compared to commercial fishing. However, for inland water bodies in densely populated areas, this assumption may not be supported. In this study, we demonstrate variable stock recovery rates among different fish species with similar life histories in a large prod...

It is often assumed that recreational fishing has negligible impact on fish stocks compared to commercial fishing. Yet, for inland water bodies in densely populated areas, this is unlikely to be true. In this study we demonstrate remarkably variable stock recovery rates among different fish species with similar life histories in a large productive...

Many inland ecosystems (lakes, rivers, reservoirs, lagoons) around the world undergo regular biological monitoring surveys, including monitoring the abundance, biomass and size structure of fish communities. Yet, the majority of fish monitoring datasets for inland ecosystems remain inaccessible. This is especially true for historical datasets from...

The invasion of non-native species into an ecosystem can markedly alter the structure and functioning of the system. Yet, we have limited knowledge of the factors that determine invasion success. Behavioural interactions have been suggested as critical determinants of invasion success in animals, but the exact mechanisms are less well known. We inv...

Declines of large predatory fish due to overexploitation are restructuring food webs across the globe. It is now becoming evident that restoring these altered food webs requires addressing not only ecological processes, but evolutionary ones as well, because human‐induced rapid evolution may in turn affect ecological dynamics. We studied the potent...

Declines of large predatory fish due to overexploitation are restructuring food webs across the globe. It is now becoming evident that restoring these altered food webs requires addressing not only ecological processes, but evolutionary ones as well, because human-induced rapid evolution may in turn affect ecological dynamics. In the central Baltic...

Climate change is likely to increasingly impact estuarine fish populations. Changes in water temperature or salinity can have deleterious effects on fish growth and behaviour. A decrease in the abundance of freshwater fish in the northern areas of the Curonian Lagoon has been attributed to increased salinity of inflowing water from the Baltic Sea....

Morphometrics is a beneficial, straightforward and relatively simple tool for fish stock delineation and identification. Analysis of spatial divergence, and morphological traits in relation to other factors, are of high interest both for management and in ecological studies. Morphology can help to delineate stocks, inform about local adaptations as...

Stocks of the European eel Anguilla anguilla have been in a steep decline since the 1980s. Stocking of water bodies with juvenile eels captured in the wild to establish or enhance local populations has been a common practise in Europe for many decades. However, the degree of contribution by stocked eels to natural spawning capacity is poorly known...

Identification of ecologically mediated mechanisms that drive population dynamical changes in fish communities and polymorphic fish stocks such as those of whitefish, Coregonus lavaretus, requires data that are seldom available in freshwater systems. We assessed the stock of each morphologically distinguishable whitefish form (native lesser sparsel...

The three-spined stickleback (Gasterosteus aculeatus L., hereafter ‘stickleback’) is a common mesopredatory fish in marine, coastal and freshwater areas. In large parts of the Baltic Sea, stickleback densities have increased >10-fold during the last decades, and it is now one of the dominating fish species both in terms of biomass and effects on lo...

Summary of some studies on three-spined stickleback diet. (DOCX)

Taxa found in three-spined stickleback stomachs as revealed by DNA metabarcoding (Primates and Aves excluded). Items in italics were considered as secondary/ accidental prey %Fbar- frequency of occurrence (percentage of stomachs in which a prey was present). (DOCX)

Diet of three-spined stickleback as revealed by visual stomach content analysis. %Fvis—the percentage of stomachs in which a prey was present. (DOCX)

Stickleback size (total length, mm) distribution in a sample. (TIF)

Gammaridae size distribution in the bays studied. (TIF)

Comparison of quantification from OTU reads and results of visual stomach content analysis. (DOCX)

Determination of the geographic boundaries that define a stock is a key challenge in fisheries management. Acquiring an understanding of spatial distribution and migration patterns of pikeperch Sander lucioperca populations in the south-eastern Baltic Sea region would help to delineate the stocks and contribute towards sustainable exploitation of t...

Enhancement of depleted European eel (Anguilla anguilla L.) populations since the 1980s shifted towards stocking on-grown eels in preference to glass eels because of a perception that releasing on-grown eels improved rates of survival. On-growing beyond the glass eel stage substantially increases the costs of restocking programs so there needs to b...

There is accumulating evidence of the significant role of three-spined sticklebacks (Gasterosteus aculeatus) for ecosystem structure and functioning in coastal areas of the Baltic Sea, but little is known about the role of the species in the pelagic foodwebs of the Baltic and its interaction with other planktivorous fish species. In this study, we...

Conflict arises in fisheries worldwide when piscivorous birds target fish species of commercial value. This paper presents a method for estimating size selectivity functions for piscivores and uses it to compare predation selectivities of Great Cormorants (Phalacrocorax carbo sinensis L. 1758) with that of gill-net fishing on a European perch (Perc...

Three stochastic versions of the Gompertz growth model were used to parameterize total length (L(T) )-at-age data for perch Perca fluviatilis, an important target species for commercial and recreational fishers and a food species for predatory fishes and aquatic birds. Each model addresses growth heterogeneity by incorporating random parameters fro...

The aspects of the perch (Perca fluviatilis) population dynamics in the Curonian Lagoon were evaluated based on the age structure of the population, which was assessed using otoliths (N = 488) sampled in 2009. Estimations were done employing FAO FISAT II software. Analysis of length-at-age data showed the asymptotic length (L∞) of 49.99 cm and the...