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Article

Use of Electrofishing to Limit the Spread of a Non-Indigenous Fish Species in the Impoundment of Aoos Springs (Greece)

by
Athina Ziou
1,
Alexandra S. Douligeri
1,
Nikolaos Kiriazis
2,
Athanasios Korakis
2,
Nikolaos Petsis
2,
Dimitrios K. Moutopoulos
1,* and
George Katselis
1
1
Department of Fisheries & Aquaculture, University of Patras, 30200 Mesolongi, Greece
2
Management Agency of Northern Pindos National Park, 44007 Aspraggeloi Zagori, Greece
*
Author to whom correspondence should be addressed.
Limnol. Rev. 2024, 24(3), 374-384; https://doi.org/10.3390/limnolrev24030022
Submission received: 29 March 2024 / Revised: 4 July 2024 / Accepted: 5 August 2024 / Published: 10 September 2024
Browse Figures
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Abstract

:
The impoundment of Aoos springs was created in 1990 to facilitate hydroelectric production, and fish fauna has been enriched through the years due to deliberate or accidental fish stockings, with certain invasive alien fish species arising (i.e., Lepomis gibbosus, Carassius gibelio), some of which are ranked among the most dangerous species for global biodiversity. A three-year monitoring survey was conducting to map the nesting areas of Pumpkinseed, L. gibbosus, to assess the effectiveness of electrofishing as an active method to reduce the spread of the corresponding species and to identify the impact of the L. gibbosus on native species. The largest percentage of nests was found in areas with silty-sand bottoms (53.4%) and low vegetation. The potential nesting area was estimated at 1.97 km2 and the area of confirmed nesting was 0.33 km2. The species appeared to nest in a small area, compared to the potential nesting area. The results also indicate that a significant percentage of the target species (71.6% of the total number of species) was removed, with an average time per sampling of 1.2 ± 1 h, whereas the impact on the other native species was minimal. These results are important for designing and implementing programs for the eradication or reduction of L. gibbosus in the impoundment of Aoos springs.

1. Introduction

Invasive alien species (IAS) are known to cause adverse environmental, economic and social impacts, such as changes in populations of native species, pathogen transfer, and significant irreversible changes in the natural environment [1]. As a result of these, IAS have been the subject of international agreements, initiatives, regulations and conservation strategies aimed at preventing their spread, preserving biodiversity, and the timely eradication and management of established populations [2].
Inland fauna in Greece exhibited one of the highest degrees of endemicity in Europe [3,4,5]. However, these populations are under severe pressure, due to environmental conditions and human activities, which are further enhanced by the introduction and spread of invasive species [6,7,8]. Pumpkinseed Lepomis gibbosus, Linnaeus 1758 was first reported in Greece in 1885 [9], and the first settled population was recorded approximately 100 years later in the Aliakmonas River, in Macedonia (Northwest Greece) [10]. It prefers shallow waters, with little water movement and enough vegetation, and the temperature it lives in ranges from 4 °C to 30 °C [11]. L. gibossus survives and reproduces in a wide range of habitats [12], and in Greek ecosystems has significant impacts on the biodiversity of the ecosystems in which it settles [13].
The impoundment of Aoos springs has evolved into an important mountainous aquatic ecosystem with an abundance of endemic aquatic organisms (i.e., Salmo farioides Karaman, 1938, Barbus prespensis Karaman, 1924, Squalius sp. (Aoos population) and Alburnoides bipunctatus (Bloch, 1782) [14]), whereas certain IAS (i.e., L. gibossus, Carassius gibelio) have been introduced into the system, some of which are ranked among the most dangerous species for global biodiversity (IUCN/GISP & SEBI 2010), but also for the lake’s aquatic fauna. IAS are dispersed, and have survived and reproduced, in multiple locations across a small or large range of habitats and range of occurrence, and are responsible for declining populations of native fauna. Thus, IAS needed to be managed [15,16]. L. gibbosus was recently introduced into the impoundment of Aoos springs during the middle of the preceding decade [14].
The species group deserves management consideration since it unquestionably poses major threats to biodiversity and ecological integrity in a variety of European inland water types [17]. In this context, L. gibbosus has been selected to visualize the nesting areas of the species, to assess the effectiveness of electrofishing as an active method to reduce its population and to identify the impact of electrofishing on the other native species. The EU recommends electrofishing as the preferred approach for mechanically removing the population of Pumpkinseed that has become over-established in a system, since it has the least impact on other species [18]. The mapping of the nesting areas of L. gibossus is a catalytic element for the establishment of species population during the most sensitive period of reproduction, and to assess the effectiveness of electrofishing as an active method to manage its population. Species’ nests are identified and counted, and the species’ active breeding areas certified, to classify the lake’s areas of greatest interest, based on the possibility that these areas constitute a breeding ground for the species. L. gibbosus undertakes multiple reproductive efforts during the breeding season, and its males crowd in the same area and create nests. Its reproductive behavior is based on parental care, with male individuals of the species sheltering and caring for eggs and newly hatched juveniles in the nest [19]. The hatching of eggs lasts from three to six days, depending on the temperature of the water [19,20,21].
The Managing Body of Northern Pindos, in the context of actions for the conservation of biodiversity, has set as a priority a reduction in the spread of L. gibossus and its impacts on the impoundment of Aoos springs. Electrofishing is a non-lethal active sampling technique, which is effective in clean, shallow water [3]. It can be carried out in various ways, such as with portable devices or from a boat, using electricity to anesthetize the fish momentarily or to force them to swim against their will into a field for collection [20]. According to [22], in Lake Balaton (Hungary), electrofishing performed better, and more Pumpkinseeds were caught than when using other methods in shallow areas. The method of removing the species through electrofishing is a possible response measure, because it has the smallest number of negative effects on native fish populations, compared to other removal methods [13,23].

2. Materials and Methods

2.1. Identification of Lepomis gibbosus’ Nesting Areas

The impoundment of Aoos springs is an “alpine type” ecosystem located at an altitude of 1343 m, in the mountainous area of northern Pindos (Figure 1). Abiotic and biotic features of the studied system have been adequately described in [24,25,26,27]. During this study, water temperatures ranged from 7.1 °C to 23.9 °C, the maximum depth was 54 m, and the average conductivity was 145.5 μS/cm. The annual water level fluctuations ranged between 6 and 8 m, with a mean (for the 1992–2022 period) value of 0.3 m/10 days, increasing from December to April and declining from May to November. The substrate of the system consists of either a muddy–sandy type with little overlap of aquatic vegetation, rocky, or a steep slope of the coastline.
The identification of the nesting areas of L. gibbosus was carried out in 2021 during its breeding season, which, according to [28], starts in May and lasts until September, although the samplings continued in October. The nests were recorded each year in the same positions, and up to 2 m deep. All visible nests were counted in the water and on the dried bottom after a drop in the water level due to the operation of the hydroelectric power station. The data on the spatial distribution of the nests taken during the field visits were analyzed and correlated with satellite images from the Sentinel-2 mission (https://scihub.copernicus.eu/dhus/#/home accessed on 20 May 2024) and the daily recordings of the water level reported by the hydroelectric power station. Data on the daily water level were analyzed from 1 November 1990 to 31 October 2021. Based on these data, the marginal lower level was estimated, beyond which the presence of nests was not recorded, nor was the seasonal change in the surface of the lake during the breeding season of the species.
Satellite images of the Sentinel-2 mission taken on the same date or as close as possible to it were then sought, covering the search area without cloud cover. From the available satellite images of the Sentinel-2 mission, the image taken on 14 April 2016 was selected, in which the lake level corresponds to 1342.04 m. Using the image above, the extent of the lake was determined during the phase of its maximum level. Then, with various satellite image tests, an image was sought showing the surface of the lake with the minimum recorded number of nests of the species, located at the water’s surface. The available satellite images show an area of a lake containing the minimum number of nests of the species, and the next available image shows the extent of the lake that does not contain nests of the species, identifying the lower sub-zone of distribution of the nesting of Pumpkinseed. From the dates of the last two pictures and the station logbook, the lowest nesting level of the species was found as the average value of the last two stations, while the lake area determined by the second figure (with zero nests) was taken as the coastline of the lake surface that defines the lower spatial nesting boundary of the species. From the above, the value estimated by use of the Sentinel-2 satellite image on 8 June 2019 was considered as a marginal lower level with a lake level equal to 1339.45 m. Subsequently, the nesting zone was determined as the difference between the extent of the maximum level of the pond and the extent of the lower nesting limit of the species.
The delineation of water and land (determination of the extent of the lake) was performed using channels B03 and B08 in Q.GIS for each image, and the NDWI index (https://custom-scripts.sentinel-hub.com/custom-scripts/sentinel-2/ndwi/ accessed on 20 May 2024) was calculated with a spatial resolution of 10 m.
N D W I = D N G − D N ( N I R ) D N G + D N ( N I R )
where DN(NIR) is the value of the pixel in the near infrared channel and DN(G) in the green channel. The data collected were mapped and analyzed on the Q.GIS 3.18.2 platform. Statistical analyses were carried out using the statistical package IBMSPSS Statistics 27.0.1.0 [29].

2.2. Reduction in the Spread of the Invasive Lepomis gibbosus

To evaluate the reduction in the spread of L. gibbosus population from the impoundment of Aoos springs, experimental electrofishing from the coast was applied around the lake during the day, using a portable electrofishing device—Hans-Grassel GmbH (Schönau a, Germany) battery-powered backpack, Model IG200-2, DC (pulsed), with 1.5 KW output power, 35–100 Hz, and max. 850 V (Schönau, Germany). Electrofishing was conducted in three years (July–November 2021, June–September 2022 and June–August 2023) at areas where Pumpkinseed nests were identified based on the surveys that took place in 2021, in the southern part of the lake, in creeks, and in shallow waters (Figure 1). The identification of the Pumpkinseed nests took place during the breeding season of the species, from May to October 2021. Samplings were conducted by one operator handling the electrofishing device, followed by one or two individuals collecting all stunned specimens, which were afterwards transferred to a recovery basin, and their species and number were recorded. These data were used to calculate the recovery rate of non-target species; that is, the percentage of individuals that recovered and returned to the lake. The recovery rate was calculated by dividing the number of individuals that recovered by the total number of non-target fish that were caught. Specimens of L. gibbosus were euthanized in an MS-222 solution, according to the manufacture’s guidelines, and were kept in formalin (1:5 solution) for further study in the laboratory. In each sampling phase, the start and end time of the sampling were recorded. The average voltage used was 600 V, with an average of 70 Hz; however, depending on the conditions, there may have been adjustments.

3. Results

3.1. Nesting Areas

A total of 440 nests of the species were recorded in 205 locations (Figure 2). More than half of the nests (53.4%) were recorded on muddy–sandy substrate, with more than half of the nests (54.1%) found in areas with zero aquatic vegetation cover, and the remaining (45.2%) were found in areas with little overlap of aquatic vegetation. Most nests (56.8%) were in areas where there was no stream runoff. The potential nesting area was estimated to be equal to 1.97 km2, and the area of the confirmed spawning grounds was estimated to be equal to 0.33 km2, which is 16.9% of the possible spawning zone (Figure 2).
Nesting seems to take place in the southern and south-western part of the lake, characterized by creeks with calm waters and a gentle slope of the seabed, with a substrate preferred by the Pumpkinseed (a total of 0.031 km2). Some nests were found in the northern and northeastern parts of the lake, close to the main outflows of the rivers in the impoundment of Aoos springs. These is a large area of possible nesting ground (0.052 km2 and 0.046 km2), and both the slope of the seabed and the substrate contribute to the appropriate conditions for nesting, but they are near stables and grazing areas for large animals. In these places, the coast was disturbed by herd trampling. In the northern part of the lake, no nesting was recorded, as this area is characterized by a rocky substrate, a steep slope of the coastline and a landscaped coastline with riprap. Therefore, the nests in the possible nesting zone were located mainly in shallow areas near the shore of the lake, with calm waters and a gentle slope of the seabed, while the density of the nests in the areas recorded was estimated to range from 0.27 to 15 nests per 490 m2 (Figure 3).

3.2. Reduction in the Spread of the Invasive Species in Short-Term Level

A total of 63 sampling trials was conducted, of which 25 trials occurred between May and October 2021, followed by 13 trials between June and September 2022, and another 25 trials between June and August 2023. A total of 1600 fish individuals were collected during these trials, with L. gibbosus comprising the majority, at 1147 individuals (71.6%). The remaining 453 individuals (28.4%) fit into five other species, Alburnoides bipunctatus, Barbus prespensis, Cyprinus carpio, Carassius gibelio, and Squalius sp. Aoos. In 2021, a total of 738 L. gibbosus individuals were captured, alongside 270 individuals from other species. In 2022, the count for L. gibbosus reduced to 163 individuals, while 143 individuals from other species were caught. Finally, in 2023, there were 246 L. gibbosus individuals captured, with only 40 individuals from other species being caught.
The recovery rates varied across species, ranging from 55.2% for B. prespensis to 64.3% for C. carpio. In contrast, the recovery rates for the other species (A. bipuntactus, C. gibellio, and S. sp. Aoos) ranged from 80% to 83%. Despite the relatively higher mortality rates observed in B. prespensis and C. carpio, they comprised 2.3% (27 individuals) and 3.6% (42 individuals) of the sample. The length and weight of L. gibbosus individuals collected through electrofishing were measured, and the length distribution of the species was estimated. Most individuals captured belonged to the length classes of 5 cm to 9 cm (Table 1).
The smallest individuals of the L. gibbosus collected were four individuals in the length class of 2–3 cm. Additionally, the performances in terms of the number of L. gibbosus individuals per electrofishing application (CPUE(N/sampling)) were estimated for the total number of individuals and length classes <5 cm, 5–7 cm, and >7 cm (Figure 3). The mean performances (individuals/sample) for the total numbers of individuals were 21.85, 18.3, and 7.63 N/sample for the years 2021, 2022, and 2023, respectively. There was a statistically significant difference in the mean performance across years (ANOVA; p < 0.05). The mean performances for individuals with L < 5 cm were 2.13, 0.95, and 0.70 N/sample for the years 2021, 2022, and 2023, respectively, with no statistical difference in the mean performance across years (ANOVA; p > 0.05). The mean performances for individuals with L 5–7 cm were 8.65, 11.81, and 2.5 N/sample for the years 2021, 2022, and 2023, respectively, with a statistically significant difference in the mean performance across years (ANOVA; p). The performance ratio for 2023 compared to the mean performance for the years 2021 and 2022 was 0.25 (a decrease of 75.1%). The mean performances for individuals with L > 7 cm were 6.12, 5.21, and 2.93 N/sample for the years 2021, 2022, and 2023, respectively, with a statistically significant difference in the mean performance across years (ANOVA; p < 0.05). The performance ratio for 2023 compared to the mean performance of the years 2021 and 2022 was 0.517 (a decrease of 48.2%). A greater reduction in individuals per operation was observed between the years 2021 and 2022 compared to 2023 in individuals with a length class of 5–7 cm compared to individuals with a length class of >7 cm (decrease of 75.1% vs. 48.2%).
The average sampling time per day for all trials was calculated to be 1.2 ± 1 h. In 2021, the longest average sampling time per trial was 2.3 h, with an overall average sampling time of 1.4 ± 1 h for the year. Conversely, in 2022, the average sampling time was 1 ± 0.4 h, and in 2023, it reduced further to 0.4 ± 0.3 h. The operational time excludes equipment preparation and movement between regions. Typically, equipment preparation takes no more than 15 min per operation, and movement between stations does not exceed 30 min, given that access to the coast by car is available at all stations. Consequently, it is estimated that a two-person team can cover between two and seven positions per day within an 8 h period. With a 6 h work window, the team can cover one to five positions.

4. Discussion

The impoundment of Aoos springs was created almost 30 years ago to meet the needs of hydroelectric production, and its fish fauna has gradually been enriched due to deliberate or accidental fish stockings with native or non-native fish species. The aims of the present study were to visualize the nesting areas of the species, to assess the effectiveness of electrofishing as an active method to reduce its population, and to identify the impacts of L. gibbosus on the other native species. The definition of national targets for detecting and controlling IAS is a critical area of research [30].
Regarding the nesting of L. gibbosus, it has been observed that the substrate type significantly influences this process [31], with the species showing a preference against dense mud [32,33,34]. However, from the results, it seems clear that the predominant substrate for the nesting of L. gibbosus in the impoundment of Aoos springs is muddy–sandy, while in the other options (gravelly, rocky) we find a small percentage (4–18%) of the total nests. However, on Lake Balaton in central Europe (Hungary), L. gibbosus exhibit a high preference for rocky areas and riprap throughout the year, but in the spring, when the breeding season begins, the fish were mainly found in areas with a muddy–sandy substrate and reeds [22]. In the impoundment of Aoos springs, access to the rocky areas was difficult due to the sampling methodology, and so these points were underestimated in relation to the rest areas. In the areas where the nests were recorded, there was no aquatic vegetation or the percentage of overlap was small, as the species prefers “clean” areas for the creation of its nests [31]. This preference is probably overlooked by the species when there are external restrictions on breeding, such as predators and competition for food or nesting areas at the peak of the breeding season [35]. In addition, given that the nests are recorded each year in the same positions, and in a zone up to 2 m deep, it was evident that there was no change in the positions of the nests due to the use of electrofishing.
The successful nesting of L. gibbosus is the result of biotic and abiotic factors. Biotic factors include the density and structure of the fish community and intraspecific competition, as individuals of the species prefer specific depths and substrates for their nests [36,37]. Abiotic factors are mainly related to weather changes such as strong winds, storms [38], and, in the case of the impoundment of Aoos springs during the summer months, an important role is played by the fall in the lake level. In addition, the lake was observed to help the shore recover from animal trampling (sheep, goats, cattle and horses) during the nesting period of species in areas that are breeding grounds, which is likely to lead to failed reproduction at places where this phenomenon is observed. In conclusion, the species appears to breed in a small area (0.33 km2) in relation to the potential nesting area (1.96 km2), which can be covered operationally (use of electrofishing) to prevent reproductive process.
Electrofishing in the impoundment of Aoos springs was deliberately targeted at the nesting grounds of L. gibbosus during their breeding period, aiming to remove the reproductive population. The fishing zone of electrofishing was 70 m wide (100 steps) to a depth of 1 m. Under electrofishing as an active method of reducing the spread of Pumpkinseed, the dominant species of individuals caught was Pumpkinseed (64.3%), and only 35.7% of the total consisted of other species. According to [39], the removal of male individuals from the nests results in complete nest failure. Additionally, larvae and juveniles of the species are concentrated in nest areas, making them easy targets for electrofishing [40]. The absence of small-sized individuals in the sample is expected as their size does not allow for their detection or retention in a fishing net. The implementation of electrofishing can potentially disrupt the reproductive process. Exposing mature fish to electrofishing fields may result in significant harm or the premature release of gametes, consequently impacting the viability of fertilized eggs [41]. Furthermore, deploying electrofishing in active spawning areas can profoundly affect the survival of larvae within or on the substrate, particularly during their vulnerable developmental stages [41,42,43]. While the exposure of recently hatched nymphs may not lead to substantial mortality, it could hinder growth rates for a considerable period [41,44]. It appears that the intensity and duration of exposure are crucial electrical factors influencing larvae and small-sized individuals [41,42,43].
Furthermore, the remaining fish species that are caught are part of the lake’s fish fauna, with species such as C. carpio and C. gibellio being introduced into the impoundment of Aoos springs. Moreover, electrofishing was not applied in areas inhabited or preferred by the species caught, nor did it affect their reproductive areas, indicating that their fishing is likely due to the occasional occurrence of the species in the study areas [5,45,46]. Particularly, regarding C. carpio, in temperate regions it reproduces in spring until mid-summer, in shallow areas with dense aquatic vegetation, which are also the habitats where the larvae of the species live [45]. In the case of the impoundment of Aoos springs, the largest percentage of Pumpkinseed nesting areas were found in areas with zero aquatic cover (54%) or very little aquatic plant cover (45.2%). C. gibellio mainly inhabits stagnant waters with heavy aquatic vegetation, and its juveniles occur in reedy areas. The species breeds on shallow, warm shores with submerged vegetation [45]. B. prespensis is found in lowland lakes and bodies of water, with little current, as well as in tributaries or in sandy bottom areas of lakes, near underground springs [47]. Only 27 individuals of B. prespensis (1.9% of the total individuals caught) were caught during the sampling in the impoundment of Aoos springs. A. bipunctatus, of which 362 individuals were caught (24.9% of the total population caught), lived in fast-flowing, well-oxygenated streams and rivers. Adults as well as juveniles appear in small rivers, in the open waters of currents and in rivers with very calm waters. It breeds in small groups and deposits its eggs deep in gravel with a fast current, unlike Pumpkinseed, which prefers calm waters with a gentle flow [45]. In the impoundment of Aoos springs, the studied species does not seem to prefer gravel substrates for nesting, as only 4% of all nests were recorded in these substrates. S. sp. Aoos lives in streams with strong flow and clear water, and probably breeds on gravelly substrates. In total, only 78 individuals were caught—5.4% of the total caught population [45]. Consequently, electricity is not applied to areas inhabited or preferred by the fished species, nor are their breeding grounds affected. This indicates that their fishing is likely due to the occasional occurrence of the species in the study areas. As such, their representation suggests a sporadic occurrence in the study area. Thus, it is reasonable to conclude that the impact of electrofishing on direct mortality in these populations is likely minimal. In this framework, the monitoring of IAS might be facilitated by means of environmental DNA (eDNA), which has been recently suggested to show a particularly high potential applicability in improving biomonitoring [48,49]. Using eDNA, the identification of individual target species using single-species techniques, such as qPCRs, could help to describe the compositions of target species communities via metabarcoding [48,49].
The use of electrofishing, under specific conditions, focusing on the breeding grounds or the gathering places of the species, is profitable in the context of L. gibbosus. Thus, this tool is sufficient for use in the management of the population of Pumpkinseed in the impoundment of Aoos springs. On the other hand, the use of electrofishing with proper management results in relatively small—at least in the short term—mortality in the other species of the lake [50]. Also, although there may be spatial variations in the fishing efforts due to the possible different extents between the positions, these do not affect the results, because our study concerns a comparison of 3 years performed in the same polling positions. Finally, the time required per station allows all possible concentration points of the species to be covered in less than a month of field work. The above concerns important elements related to the design and organization of programs for the elimination or reduction of the population of the species in the impoundment of Aoos springs.

Author Contributions

Conceptualization, G.K.; methodology, G.K.; formal analysis, G.K. and A.Z.; investigation, A.Z., A.S.D., N.K., A.K., N.P. and G.K.; resources, A.Z., A.S.D., N.K., A.K., N.P. and G.K.; data curation, G.K., A.Z. and D.K.M.; writing—review and editing, A.Z., A.S.D., A.K., D.K.M. and G.K.; supervision, G.K.; project administration, N.K., A.K. and N.P.; funding acquisition, G.K. All authors have read and agreed to the published version of the manuscript.

Funding

This research was performed in the framework of the research project “Preliminary estimation of the fish fauna and water quality of the impoundment of Aoos springs with emphasis on the sustainable management of the non-native species” funded by the Management Agency of Northern Pindos National Park through the Operational Program “Epirus 2014–2020”.

Data Availability Statement

Data supporting the reported results of the study can be provided upon request to the first author.

Acknowledgments

The authors want to thank the staff of the Management Unit of Northern Pindos National Park (N.E.C.C.A.) for their involvement in the monitoring schemes, and the Public Power Corporation S.A. for providing their boat and assisting in the fish sampling.

Conflicts of Interest

The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript; or in the decision to publish the results.

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Limnolrev 24 00022 g001
Figure 1. Electrofishing sampling areas in Aoos springs dam Lake. With light blue colour the Aoos springs dam Lake has been presented.
Figure 1. Electrofishing sampling areas in Aoos springs dam Lake. With light blue colour the Aoos springs dam Lake has been presented.
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Figure 2. (A) L. gibbosus’ nesting zone and (B) nest density distribution.
Figure 2. (A) L. gibbosus’ nesting zone and (B) nest density distribution.
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Figure 3. Annual performance in terms of the number of individuals of the species L. gibbosus per electrofishing application (CPUE(N/sampling)).
Figure 3. Annual performance in terms of the number of individuals of the species L. gibbosus per electrofishing application (CPUE(N/sampling)).
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Table 1. Length distribution of the species L. gibbosus collected during electrofishing applications in the years 2001–2023.
Table 1. Length distribution of the species L. gibbosus collected during electrofishing applications in the years 2001–2023.
Length (cm)202120222023Total
2–31 34
3–422 4163
4–53211952
5–6693532136
6–72167151338
7–81542849231
8–9612326110
9–102141136
10–1151814
11–12 33
Total581163243987
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Ziou, A.; Douligeri, A.S.; Kiriazis, N.; Korakis, A.; Petsis, N.; Moutopoulos, D.K.; Katselis, G. Use of Electrofishing to Limit the Spread of a Non-Indigenous Fish Species in the Impoundment of Aoos Springs (Greece). Limnol. Rev. 2024, 24, 374-384. https://doi.org/10.3390/limnolrev24030022

AMA Style

Ziou A, Douligeri AS, Kiriazis N, Korakis A, Petsis N, Moutopoulos DK, Katselis G. Use of Electrofishing to Limit the Spread of a Non-Indigenous Fish Species in the Impoundment of Aoos Springs (Greece). Limnological Review. 2024; 24(3):374-384. https://doi.org/10.3390/limnolrev24030022

Chicago/Turabian Style

Ziou, Athina, Alexandra S. Douligeri, Nikolaos Kiriazis, Athanasios Korakis, Nikolaos Petsis, Dimitrios K. Moutopoulos, and George Katselis. 2024. "Use of Electrofishing to Limit the Spread of a Non-Indigenous Fish Species in the Impoundment of Aoos Springs (Greece)" Limnological Review 24, no. 3: 374-384. https://doi.org/10.3390/limnolrev24030022

APA Style

Ziou, A., Douligeri, A. S., Kiriazis, N., Korakis, A., Petsis, N., Moutopoulos, D. K., & Katselis, G. (2024). Use of Electrofishing to Limit the Spread of a Non-Indigenous Fish Species in the Impoundment of Aoos Springs (Greece). Limnological Review, 24(3), 374-384. https://doi.org/10.3390/limnolrev24030022

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