Abstract
Freshwater ecosystems face increasing pressures from non-native species, including Common carp (Cyprinus carpio), which is considered one of the world’s most damaging invasive species. Despite its documented ecological impacts, carp is an important target of recreational fisheries in many regions. Understanding the socio-economic and perceptual dimensions of carp fishing is therefore relevant to freshwater conservation and management. Using Italy as a nationwide case study, we investigated carp angler profiles, fishing behaviour, economic indicators, and perceptions of the ecological role of carp. An anonymous 24-question online survey yielded 911 valid responses from an estimated population of approximately 20,000 carp anglers. Factor Analysis of Mixed Data (FAMD) was used to identify gradients structuring angler profiles. Respondents were predominantly male (96.4% ± 1.2%), aged 25–45 years (60.3% ± 3.2%), with high-school education (60.8% ± 3.2%) and employed (89.7% ± 2.0%). Annual expenditure among weekly anglers averaged €5,085 ± 214. This expenditure may serve as a proxy for the potential economic value associated with the cultural ecosystem service of recreational carp fishing, although it does not constitute a full economic valuation. Most respondents (87.9% ± 2.1%) perceived carp as ecologically beneficial, contrasting with scientific evidence documenting negative effects on water quality, benthic communities, and native biodiversity. FAMD identified two main gradients: one distinguishing high-effort specialists fishing in lentic habitats from more opportunistic anglers in lotic systems, and another reflecting demographic and educational differences. Perceived ecological role showed only weak associations with fishing effort, indicating limited correspondence between species perception and behavioural investment. The results illustrate a socio-ecological paradox in which a non-native species can simultaneously generate cultural ecosystem services while exerting ecological impacts. The expenditure indicator captures a potential component of the cultural ecosystem service associated with carp fishing but does not account for ecosystem disservices linked to carp populations or their spread. These findings highlight the importance of considering recreational benefits and stakeholder perceptions alongside ecological impacts when addressing the management of non-native carp populations.
1 Introduction
Freshwater, despite representing only 0.01% of the world’s water and approximately 0.8% of the Earth’s surface, are pivotal biodiversity hotspots (). These ecosystems are also threatened by multiple stressors, to the point that almost one-quarter of freshwater fauna is at risk of extinction (Sayer et al., 2025). In addition, recreational fishing substantially contributes to the global spread of aquatic non-native species (Yang et al., 2026).
The presence or arrival of a non-native fish species (sensu Soto et al., 2024) in a freshwater habitat is widely recognized by ecologists as detrimental to ecosystem functioning (Vitousek et al., 1996; Tarkan et al., 2015 and references therein). Nevertheless, ecological impact and societal perception do not always align, as these species might also be capable of offering a suite of cultural and provisioning ecosystem services (; Sax et al., 2022; ) or be considered naturalized (). However, public perceptions of species can potentially lead to misinformed management decisions (McDaniel et al., 1997; ; Pope et al., 2016; ).
Recreational fishing is a leisure activity relying on fish communities, therefore representing a cultural service of economic and socio-ecological importance (Morales-Nin et al., 2025 and references therein; Sbragaglia et al., 2025). On a global scale, recreational angling was estimated nearly 20 years ago to generate expenditures amounting to several billions of dollars, with the number of recreational anglers worldwide ranging from approximately 220–700 million individuals (, and references therein). Scaling the phenomenon to Europe, Morales-Nin et al. (2025) reported that ∼10% of population fish for leisure, highlighting its relevance not only economically (), but also promoting wellbeing and mental health (Pita et al., 2025).
The occurrence of carps among multiple freshwater habitats contribute to increase their catch rate among anglers, raising the paradox of a non-native species providing valuable ecosystem services. The capture of big carp in Europe gave aid to a complex socio-economic recreational phenomenon, nowadays spreading worldwide, called carp fishing (; ).
Carp is an umbrella terminology referring to a taxa composed of different breeds of the species Cyprinus carpio (Linnaeus, 1758) considered within the 100 world’s worst invaders (Lowe et al., 2000). This species, along with the grass carp Ctenopharyngodon idella (Valenciennes, 1844), is also increasing in popularity among carp anglers worldwide. Indeed, since the 1950s a group of eclectic anglers in the UK started conceiving a specialized fishing technique, which using specific hardened bait (e.g., boilies) targeted the bigger specimens of this species (; Milardi et al., 2015; and references therein). The capture of big carps, over 20kg, first in UK and over 30 kg few decades later across different lakes in Europe triggered the diffusion and inspired new tackle, giving aid to a complex socio-economic recreational phenomenon, nowadays spreading worldwide, called carp fishing (; ).
Additionally, carps belong to the top ten reared fish globally, with over 10 million tons produced mainly from inland aquaculture (). Moreover, in Japan between the end of the 1700s and the 1800s, an additional socio-cultural and economic interest that persists to this day began, obtained via the artificial breeding of carps aimed at selecting specific ornamental traits (e.g., colors, size), named Koi carp farming (). Their contribution to the fish farming sector and as a food source is an undeniable provisioning ecosystem service provided by these species.
However, the review conducted by Weber and Brown (2009), further implemented by the research of Vilizzi et al. (2015), gave a holistic overview of the main effects of the common carp on freshwater ecosystems. More recently, also the ecological role of the grass carp in a channels network has been pointed out (Milardi et al., 2020).
The management of the species has been addressed on a global level. acknowledged the rising interest in these species among carp anglers. They also suggested the reduction of carp biomass by angling to improve water quality and to maintain and improve aquatic ecosystem status in Germany, coupled with the protection of a smaller number of larger carp (trophy specimens) for the interests of anglers. The same authors also endorsed education programs targeting local fisheries managers and anglers to show the negative impacts of dense carp stocks, reporting how in the Netherlands, education courses succeeded in reducing stocking densities of carp (Walder and van der Spiegel, 1990). In the United States of America, where C. carpio is considered as a non-native species that negatively impacts habitat and water quality in lakes, different practical and selective removal strategies for carps have been implemented. Examples were the stocking of lakes with a small native predator of juvenile carps (Poole and Bajer, 2019), through pulsed commercial harvest (), or via extirpation using oral toxicants into corn-based baits (Poole et al., 2018). Recognizing the similar ecological impacts posed by C. carpio, Australia initiated research on a cyprinid herpesvirus as a potential biocontrol agent in 2008. This effort culminated in the National Carp Control Plan (NCCP), completed in 2022. The assessment indicated that viral biocontrol could potentially reduce national carp populations by 40%–80%, but it also highlighted uncertainties regarding the safety of viral release. Consequently, the NCCP recommended that additional research be conducted before any management decisions are made (). Also in Africa, despite being an economically important species through aquaculture farming in many countries such as Egypt (Mohammed et al., 2024), common carp management is primarily focused on controlling invasive populations through removal efforts, and preventing further spread ().
The presence of carps among Italian freshwater has been described across the entire Peninsula (Volta et al., 2011 and references therein; Vilizzi et al., 2015; Milardi et al., 2022; and references therein). Nevertheless, timing and route of carp introduction is still under debate. Both the Roman and monastic domestication, as well as the Franco-Burgundian pond culture of the 12–13th Centuries were plausible, as outlined by Vilizzi (2015). Regional regulations govern the conditions under which professional inland-water fisheries can operate; however, despite a few remaining local culinary traditions, the commercial demand for wild (non-farmed) carps remains negligible within the Italian gastronomic sector (). Furthermore, carp production is supported by a limited number of extensive or semi-intensive farms and, lately, carp rearing has been introduced into aquaponics systems (). National legislation classified C. carpio as a para-autochthonous species, a category that includes taxa introduced and naturalized before 1500 AD and therefore counted among native species (). However, from a biological and ecological perspective, which is the focus of this manuscript, carps are considered non-native, since speciation typically requires approximately 2 million years (). In addition, carp fishing targeted both C. carpio and C. idella (a non-native species), further supporting this choice.
It is therefore clear that researchers, stakeholders and politicians involved in effective and adaptive water basin management shared a high level of interest in these species, since the last 90 years, which is still actual (Vilizzi et al., 2015 and references therein; Stuart et al., 2021).
Whereas the negative impacts of non-native species on ecosystem services and human wellbeing have been widely assessed and valued, for example, in the case of carps (; Pejchar and Mooney, 2009; Weber and Brown, 2009; Vilizzi et al., 2015), the role of carp angler and the potential benefits provided by non-native species in the broader context of managing freshwater ecosystems for their ecological functioning remain poorly explored (Sax et al., 2022). Evaluating these social benefits is necessary to prevent public backlash against control measures and ensure long-term policy compliance.
Thus, through a survey targeting Italy as a representative nationwide study case, this manuscript aimed to highlight both (1) the ongoing attractiveness of carp to anglers to the point to adopt a specialized fishing technique, as well as carp anglers’ socio-cultural profiles, and (2) the potential positive ecosystem services provided by a cosmopolitan species non-native to Italy. It was therefore explored (3) the carp anglers’ perceptions of carp’s role in aquatic ecosystems and the appropriate ecological functioning of the latter.
2 Materials and methods
2.1 Study area
Italy (Southern Europe) covers a total area of 301,336 km2, characterized by a highly heterogeneous climate, ranging from alpine conditions in the north to Mediterranean climates along the coasts and in the southern regions. This climatic variability, together with complex geomorphology, supports a wide diversity of hydrological systems. Across its territory, Italy hosts numerous and heterogeneous water bodies, including small channels, irrigation canals, reservoirs, pit lakes, rivers and lakes of different origins (; ).
The widespread presence and abundance of carps throughout Italy’s inland waters coupled with the presence of ∼20,000 carp anglers in Italy (L. Montanari, experienced carp angler, brand ambassador and reference contact of the biggest carp trade show in Italy, personal communication, 9 February 2025), determined Italy as a representative nationwide study case aligning with the scope of the manuscript.
2.2 Survey protocol and quantified metrics
After a preliminary bibliographic inspection, questionnaires emerged as an appropriate methodology to answer our research questions (; van der Hammen and Chen, 2020; Pita et al., 2025). Therefore, an anonymous and voluntary 24 single-answer questionnaire was designed as the means of data collection. The survey structure was arranged on previous examples in the literature (e.g., Morales-Nin et al., 2025). Before submission, questions were discussed and cross-validated by a team of ecologists, ecosystem service and socio-economic experts (M.Gaglio, personal communication). The survey encompassed an exploration of both demographic characteristics and the habitual practices of carp anglers.
In contrast to , no incentives were provided to respondents. Although participation was voluntary and the sampling design was not strictly probabilistic (Vaske, 2019), the event-based approach ensured broad national coverage and substantial representation of the active carp fishing community. However, the explorative nature of the present work justified the approach (Vaske et al., 2025), often generally applied for understanding niche groups dynamics (). Following the successful administration protocol described by , the distribution of questionnaires occurred in two distinct modalities: (1) during the Italian specialized tradeshow (https://www.carpparma.it/, 8–9 February 2025), which represents a primary gathering event for the Italian carp fishing community (2) through the online Survio platform (https://www.survio.com/it/, last access 30 April 2025). The dissemination of questionnaires was facilitated by the main national carp angling association (https://www.carpfishingitalia.it/) together with tradeshow staff.
To attribute value to a single ecosystem service offered by the suite of habitat considered in the study, i.e., carp fishing - thus indirectly given by carps - we calculated a simple and effective comparable indicator reflecting it. It is worth underlying that this indicator does not account for the ecosystem disserveces generated, which calculations was out of the scope of this manuscript. The calculation of the average annual per capita fishing expenses (APE, Euro person−1 year-1) was computed by converting the expenditure categories (see Question No. 14 in Supplementary Material: Supplementary Figure S2) into midpoint values (in Euro) per session, whereas fishing frequency was converted to annual sessions (days year-1). Therefore:
The bait cost represented a fraction of APE’s indicator and is calculated on the average per capita fishing bait expenses afforded by each respondent per fishing session (BC, Euro person−1 fishing session−1). Indeed, the average quantities of bait (kg, e.g., boiles, particles, pellets, groundbait) used for baiting in a 24 h fishing session (see Question No. 16 in Supplementary Material: Supplementary Figure S2) were converted to midpoint values (in kg), whereas an average price of 7.00 Euro was set as a reliable price for 1 kg of bait mix (e.g., boilies, seeds, pellets, ground bait), based on market costs. Therefore:
The investigation further examined the economic implications of this practice and the perceptions of anglers regarding the role of carps in relation to the species of fauna and flora that coexist within aquatic ecosystems (see Supplementary Material: Supplementary Figures S1, S2).
Willingness to pay (WTP) is defined as the maximum amount an individual is prepared to give up in income to secure a good or service or to avoid its loss (; ). WTP is an indicator widely used in ecosystem-service valuation due to its capacity to include aspects such as use, non-use, existence, and inheritance values into total economic value (), as well as to provide a monetary metric compatible with cost-benefit analysis and environmental accounting (; ; Scheufele et al., 2025; and references therein). The approach is distinguished by its flexibility, wide applicability to a wide range of non-market ecosystem services, and grounded in welfare economics, reflecting individual preferences. However, WTP has several limitations. Estimates may suffer from hypothetical bias, scope insensitivity and embedding effects, as well as income constraints that may undervalue benefits for lower-income populations. Survey design choices, including scenario framing and payment vehicles, can systematically bias responses, while certain irreplaceable ecological functions may simply resist meaningful monetary valuation by respondents (; ; ).
A deeper conceptual issue is that WTP-based valuation of common goods assumes purely self-interested preferences, which tends to overlook fairness, distributive justice, and social context, with respondents typically assigning higher value to ecosystem services from which they personally benefit (Mossone, 2019).
Nevertheless, we deemed valuable to consider WTP indicators in our research, by asking carp anglers if, and if so, which categories of expenditure they would have been willing to pay -lump-sum payment - for: (a) the conservation of the overall fish community, and specifically of carps in their fishing spot, and (b) the conservation of their fishing site, keeping this last question general to assess if carp anglers care just about carp or also about the site where they fish (see Supplementary Material: Supplementary Figures S1, S2).
2.3 Statistical analysis
When the assumptions were met, including data normality assessed through plotting residuals and homogeneity of variance evaluated using Levene’s test, a one-way analysis of variance (ANOVA) was used to examine differences in APE of respondents among reported fishing frequencies. The same statistical test was used for differences in BC among both respondents’ educational qualification and habitat type chosen for fishing session respectively. Afterwards, Tukey HSD post hoc tests were used to identify statistically significance differences among pairwise comparisons.
Annual Per Capita Expenditure (APE) was calculated yielding a continuous monetary proxy. This continuous variable was used in the Factor Analysis of Mixed Data (FAMD). For chi-square tests of independence involving APE, a categorical version was derived by binning the continuous variable into five ranges (€0–1,000; €1,000–2,000; €2,000–5,000; €5,000–10,000; €10,000–15,600), spanning the observed range of the variable in the dataset. This categorical version of APE was used exclusively for chi-square analyses and does not replace the continuous variable used elsewhere in the manuscript.
To analyze whether there was a significant association between categorical variables, chi-square tests of independence were applied. To identify the cells that contributed most to the chi-square statistics, standardized residuals were examined; values with absolute magnitude greater than 2 were considered to indicate a significant contribution ().
Furthermore, mixed data factor analysis (FAMD) enabled the analysis of similarity between mixed types (quantitative and qualitative) of variables. Variables with a variance inflation factor (VIF) < 5 were selected for the analysis, while different combinations were discarded to avoid multicollinearity issues (Menard, 2001; ).
FAMD variable selection was also based on obtaining a cumulative percentage of the proportion of variance retained by the different dimensions of ∼20–40%, a commonly accepted threshold when addressing mostly categorical data (Pagès, 2004). These were: age category of respondents (Age), average kg of bait used per session by the carp angler (Aver_bait), carp anglers’ perception of the effect of carp in aquatic ecosystems (Carp_role), educational attainment of respondents (Education), APE (Expenditure), habitat preference for fishing (Habitat), and session duration in hours (Session_span). Breakages of “Session_span” were set based on a preliminary pool of 4 expert-based judgements on average fishing session duration. Ordered categorical variables (Age, Aver_bait, Carp_role, Education, and Session_span) were treated as qualitative variables in the FAMD framework, allowing the analysis to respect their ordinal nature without imposing metric assumptions about distances between categories (Pagès, 2004). The categorical variable < Habitat> and continuous variable <APE> completed the seven-variable model.
Quantitative and qualitative variables were normalized during the analysis to balance the influence of each set of variables. All analyses and graphs were performed using R v. 4.4.1 software (R Core Team, 2022).
3 Results
3.1 Survey response rate and characteristics of Italian carp anglers
Data collection in 2025 concluded after three consecutive weeks without additional responses. In total, 911 valid questionnaires were obtained over a period of approximately 3 months. One response provided by a Dutch carp angler during the tradeshow was excluded from analysis. Among respondents, affiliated with a national angling association, 79.1% completed the questionnaire via the online platform, while 20.9% were interviewed during the tradeshow. To reduce the risk of duplicate submissions, the final dataset was screened, and no entries required removal. Given the reported number of carp anglers in the study area, the broad spatial coverage, represented by at least one respondent in 16 of the 20 Italian regions, enabled a data-driven characterization of the socio-economic dynamics associated with recreational carp fishing. Respondents’ demographic characteristics and main angling habits are presented in Table 1.
TABLE 1
| Demographic characteristic | | | | | |
|---|---|---|---|---|---|
| Gender | Male | Female | NDa | | |
| %b | 96.4 ± 1.2 | 3.4 ± 1.2 | 0.2 ± 0.4 | | |
| Age class | 5–16 | 16–25 | 25–45 | 45–65 | >65 |
| %b | 1.4 ± 0.8 | 9.2 ± 1.9 | 60.3 ± 3.2 | 27.8 ± 2.9 | 1.3 ± 0.8 |
| Employment status | Student | Employed | Unemployed | Retired | |
| %b | 4.1 ± 1.3 | 89.7 ± 2.0 | 3.1 ± 1.1 | 3.1 ± 1.1 | |
| Education | None | Middle school | High school | Degree or higher | |
| %b | 1.1 ± 0.7 | 24.7 ± 2.8 | 60.8 ± 3.2 | 13.5 ± 2.2 | |
| Carp angler features | |||||
| Fishing habitat preference | Canal | Dam | Lake | River | Ticket lake |
| Stationary angler (%b) | 3.8 ± 1.3 | 0.6 ± 0.5 | 2.9 ± 1.1 | 6.2 ± 1.6 | 1.9 ± 0.9 |
| Traveller angler (%b) | 16.6 ± 2.4 | 4.1 ± 1.3 | 31.5 ± 3.0 | 26.6 ± 2.9 | 5.8 ± 1.5 |
| Fishing frequency | Weekly | Beweekly | Monthly | Quarterly | Lonthmc |
| %b | 32.2 ± 3.0 | 32.7 ± 3.0 | 30.6 ± 3.0 | 2.9 ± 1.1 | 1.6 ± 0.8 |
| Average bait used per fishing session (kg) | <5 | 5–10 | 10–20 | >20 | |
| %b | 32.7 ± 3.0 | 47.3 ± 3.2 | 14.6 ± 2.3 | 5.4 ± 1.5 | |
| Average session span (hours) | <6 | 6–24 | 24–72 | >72 | |
| %b | 7.8 ± 1.7 | 41.9 ± 3.2 | 41.8 ± 3.2 | 8.5 ± 1.8 | |
| Carp role perception | Very negative | Negative | Neutral | Positive | Very positive |
| %b | 0.1 ± 0.3 | 1.4 ± 0.8 | 11.6 ± 2.1 | 33.4 ± 3.1 | 54.5 ± 3.2 |
Categorization of demographic characteristics and features of respondents.
aND = Prefer not to declare.
bPercentages are calculated relative to the total number of respondents (n = 911). For each reported proportion, the 95% confidence interval (CI) was calculated using the Wilson score method for binomial proportions. Results are reported as percentages ± the half-width of the 95% CI, calculated as (upper CI - lower CI)/2. The intervals quantify sampling uncertainty associated with the 911 respondents and do not account for potential selection or non-response bias.
3Lonthm = Less than once every 3 months.
The majority of respondents were male (96.4% ± 1.2%) aged between 25–45 years old (60.3% ± 3.2%), most of whom has obtained a high school diploma (60.8% ± 3.2%), employed (89.7% ± 2.0%). 93.2% ± 1.6% of anglers’ community affirmed to prefer ad hoc fishing tackles catching carps (gears and baits, summarized as carp fishing technique), whereas the remaining 6.8% ± 1.6% adopted more generalist approaches. 84.5% ± 2.3% of carp anglers reported habitual travel to reach their customary fishing locations, predominantly a lake (31.5% ± 3.0%) or a river (26.6% ± 2.9%). The majority of carp anglers declared to go carp fishing at least once per month (95.5% ± 1.4%), reporting fishing sessions ranging from less than 18 h (41.9% ± 3.2), up to 72 h (41.8% ± 3.2%).
The results clearly demonstrate that carp fishing valued the target species above accessory features: 92.7% ± 1.7% of respondents would relocate if carp were absent from their usual fishing spot (Question 8), and 98% ± 0.9% practiced catch-and-release (Question 9), enabling recapture by other anglers. Auxiliary amenities held minimal importance: 70.3% ± 3.0% and 78.6% ± 2.7% considered nearby facilities or alternative activities not or slightly important, respectively (Questions 17–18, see Supplementary Material: Supplementary Figures S1, S2).
When asked to identify primary threats to fishing site conservation and fish fauna, respondents perceived poaching as the greatest threat (34.5% ± 3.1%), followed by lack of local and national interest (28.9% ± 2.9%), while remarkably, non-native species ranked lowest (3.9% ± 1.3%).
3.2 Economic quantification and perceptions of carp fishing goods
APE was calculated on a per-respondent basis. Annual expenditure decreased as fishing frequency decreased, with APE’s values decreasing from up to 5,085 ± 214.3 to 250 ± 47.3 Euro person−1 year-1, for anglers who go fishing weekly rather than less frequently than once every 3 months, respectively (Figure 1). Consequently, differences in APE and fishing frequencies were inspected, highlighting statistical differences (p < 0.001, F4,906 = 100.1). Additionally, Tukey HSD post hoc tests revealed statistically significant differences. With p-value <0.001 among the following pairwise comparisons: “Biweekly-Weekly”, “Monthly-Weekly”, “Quarterly-Weekly”, “Less than quarterly-Weekly”, “Monthly-Biweekly”, “Quarterly-Biweekly”, and “Less than quarterly-Biweekly”.
FIGURE 1
A series of Chi-square tests of independence provided no evidence of a significant association between APE and habitat choice, APE and educational qualification, and between APE and age of respondents (Supplementary Table S1).
Besides, no statistical differences also emerged in BC (Euro person−1 fishing session−1) based on the different educational qualifications of respondents (p = 0.76, F3,907 = 0.39), reflecting a shared pattern of monetary investment for angling bait among carp anglers. Conversely, statistical differences emerged in BC based on the different habitat chosen for fishing session by respondents (p < 0.001, F4,906 = 5.25), with lakes showing significantly higher mean values (see Supplementary Material: Supplementary Figures S3, S4 respectively).
3.3 Perceived ecological role of carp among anglers
Overall, a strong agreement emerged among carp anglers about the positive role of carp on the aquatic ecosystem and/or other species (fauna/flora) present in it (87.9% ± 2.1%).
Chi-square tests were used to examine associations between variables describing angling preferences. A significant association was found only between the perceived ecological carp’s role and educational qualification of respondents (Supplementary Table S3). Standardized residuals suggested that respondents who have a degree or higher educational qualification perceived ecological carp’s role as neutral more frequently than expected, or as very negative more frequently than expected (Supplementary Table S4).
No significant associations between the perceived ecological carp’s role and respondents’ age, or habitat type chosen for the fishing session emerged (Supplementary Table S3).
3.4 Drivers of angling preferences
A series of Chi-square tests of independence were performed to investigate the association among drivers of angling preferences.
A significant association between educational qualification and habitat choice for carp fishing session emerged (Supplementary Table S5). These results suggest that respondents with lower educational levels tend to prefer rivers more frequently than expected, whereas respondents with higher education favor other habitats. Indeed, rivers were preferred less frequently than expected. Moreover, respondents who have a high school qualification preferred ticket_lake less frequently than expected (Supplementary Table S6). Instead, no association between educational qualification and Aver_bait used by respondents for baiting during carp fishing session emerged (Supplementary Table S5).
Furthermore, respondents revealed a proactive WTP to preserve both the overall fish community and the fishing site where they are used to fish for carps. WTP levels were comparable for the two conservation targets, with 89.9% ± 2.1% (N = 819) of respondents willing to contribute for fish community conservation and 88.3% ± 2.2% (N = 804) for fishing site protection. The most frequently selected lump-sum payment among respondents willing to preserve both fish stocks and their fishing sites was €50–100, selected by 68.2% ± 3.0% and 65.2% ± 3.1% of respondents, respectively. The latter values were adjusted by excluding those who indicated they were not willing to pay but nonetheless answered the subsequent question - likely due to a misunderstanding - which accounted for only 1.54% and 1.98% of respondents, respectively. No significant associations between WTP for fish conservation and educational qualification or age emerged (Supplementary Table S7). The same trend was observed between WTP for the protection of the fishing site and educational qualification or age, (Supplementary Table S8).
Additionally, FAMD analysis allowed further highlighting of socio-economic and ecological association among respondents’ preferences. From the output of the dataset analyzed (n = 911), the first five dimensions, which together explained 32.2% of the variance (Figure 2A), were maintained.
FIGURE 2
Dimension 1 explained 8.6% of total variance, and Session_span, Aver_bait and APE contributed most to it (Figure 2B). Dimension 2 instead explained 6.4% of total variance, and Age, Education and Habitat contributed most to it (Figure 2C). The quality of representation of the categorical levels on the first two FAMD axes was evaluated using the sum of squared cosines (cos2) and varied substantially across categories (Figure 3). Across the 27 categorical levels, cos2 values for dimensions 1 and 2 ranged from 0 to 0.59. Five levels were strongly associated with these dimensions (cos2 > 0.40). Eight levels showed moderate representation (0.20 < cos2 < 0.40). The remaining 14 levels had low cos2 values (<0.10), indicating their variance is largely captured by higher-order dimensions (Supplementary Table S9).
FIGURE 3
4 Discussion
Even with an open questionnaire period of about 3 months, the high response rate to the survey indicates a clear and growing interest in carps among Italian specialized recreational carp anglers. Moreover, despite the non-probabilistic nature of the survey and potential self-selection biases, the results show a broad socio-demographic coverage (Table 1). We thus acknowledge the limitations of the survey and the potential bias affecting it. However, considering the response rate higher than previous research (; Morales-Nin et al., 2025), and the rigorous statistics applied, the following discussions are supported by a reliable and robust dataset.
4.1 Carp fishing as a cultural ecosystem service
Fishing is among the oldest activities that connect aquatic ecosystems with human societies (Pope et al., 2016, and references therein). While this practice has been and still is in use for millennia by people to ensure a food supply, from the last decades of the 20th Century onwards, industrialized and recreational fishing have increased in popularity (Pope et al., 2016). Narrowing the focus, people involved in recreational fishing are rising steeply, as are the suite of co-occurring potential cultural and provisioning ecosystem services (, ; Vilizzi et al., 2015; Pope et al., 2016; Sax et al., 2022).
The occurrence of carps among multiple freshwater habitats (e.g., lakes, rivers, channels, ponds, etc.) contribute to increase their catch rate among anglers, raising the paradox of a non-native species providing valuable ecosystem services.
4.2 Socio-economic indicators of recreational use
The survey results described the occurrence of this tendency also in Italy. Carp fishing involved citizens, mainly males, as previously reported for recreational fisheries in Spain (Morales-Nin et al., 2025), of different ages, ranging from 5 to over 65 years old, but also characterized by varying monthly incomes (data not shown). Van der Hammen and Chen (2020) reported young people belonging to the age group 5_16 as the most abundant fishing age class in freshwater. Despite direct comparisons not being possible, since the results presented here investigated a specialized anglers group, the most abundant age class resulted in 25_45 years old (60.3% ± 3.2% of respondents, see Table 1). The explanation lies in the fact that carp fishing requires both an important investment of time, almost 94% ± 8.1% of respondents declared that their fishing session lasts from 6 to 72h, in the range of what was previously found by in Germany, and money, which is thus possible mainly for workers. However, workers could experience a lack of free time, which can be accounted as a limited factor in recreational fishing ().
Being counted among cultural ecosystem services provided by freshwater ecosystems, carp fishing contributes to human wellbeing ( and references therein; Pita et al., 2025). At present, this specific recreational fishing technique is rarely practiced with the primary aim of consuming the captured fish (Sbragaglia et al., 2025). That said, anglers’s behaviors could lead to the collapse of the targeted fish populations (). However, regardless of few exceptions or national rules (), one of the most satisfactory features triggering the willingness to pursue another fishing session in the same fishing spot is the success of the trip in terms of catches, making the release of the captured fish (catch-and-release practice; C&R), a dogma in most cases (). Nevertheless, if the latter mentioned practice is not applied, carp fishing can also be valued as a provisioning ecosystem service derived from aquatic ecosystems (Sax et al., 2022).
Besides, carp fishing may contribute to local and national economies (). Despite this not being the focus of the research, calculated APE attributed a value to a single ecosystem service offered by the suite of habitat considered in the present study, as it is carp fishing - thus indirectly given by carp. It is crucial to remark that such a metric does not reflect either the environmental value, or the value of carp.
The economic relevance of carp fishing is reflected in the frequency of fishing sessions. APE’s values of up to 5,085 ± 214.3 Euro person−1 year-1 (see Figure 1) resulted for anglers who go fishing weekly. This amount is aligned with the average reported value of 5,490 Euro per person−1 year-1 by . Even if corrected for the current value of the Euro compared to 2003 (conversion factor = 1.457, https://rivaluta.istat.it/Rivaluta/, last accessed 27/11/2025), the potential economic relevance of carp fishing is undeniable in both Germany and Italy, and potentially wherever a high rate of carp anglers willing to invest in it is present.
However, a full economic evaluation of carp fishing is lacking in the literature, and many previously reported estimates are therefore non-exhaustive (; Scheufele et al., 2021). To credibly state that carp fishing contributes to regional or national economies requires broader assessment of parameters often omitted from simple valuations. For example, costs associated with non-native species damages or control, ecosystem-service losses, sectoral shifts in growing industries, and economy-wide effects that may reduce production elsewhere, which calls for modelling approaches beyond single-site valuations, such as input–output (IO) or computable general equilibrium (CGE) analyses (; ; Warziniack et al., 2021).
Moreover, the higher participation in carp fishing per se also poses caveats to ecological sustainability of the practice, since it translates into more access to the inland water banks, often via roads or vehicles, thus potentially damaging banks, increasing pollution (e.g., through soil compaction, litter, hydrocarbons, tire wear particles, runoff), and altering riparian and littoral habitat (O’Toole et al., 2009; Schafft et al., 2021; Song et al., 2025). Furthermore, the willingness to reach a specific habitat, as outlined in the survey’s results (see Table 1), highlighting the preference of most Italian carp anglers for river and lakes, may further contribute to habitat fragmentation, degradation of aquatic vegetation, increased erosion or sedimentation, and thereby to the alteration of ecosystem functioning in these crucial but delicate habitats (; Ottburg and Blank, 2015). Further research into addressing these aspects is thus advisable.
4.3 The social-ecological paradox of non-native species providing ecosystem services, possible implications of shifting baselines
The FAMD correlation circle (Figure 3) revealed two orthogonal gradients among the variables contributing most strongly to the ordination. The modest variance explained (15%) reflects appropriate preservation of categorical complexity rather than analytical limitation; forcing ordinal variables into metric assumptions would artificially inflate explained variance while distorting ecological relationships (Pagès, 2004). This level of variance is consistent with previous studies applying FAMD to similarly complex, mixed socio-ecological datasets (Vasquez et al., 2024).
Dimension 1 separated high-effort anglers (longer sessions, greater bait provisioning) from low-effort, younger anglers fishing river habitats with brief sessions and minimal bait - consistent with a recreational specialization gradient characteristic of heterogeneous angler populations (; ). Dimension 2 was structured primarily by age and education rather than effort: the youngest age class and respondents with no formal education loaded strongly and positively, alongside ticket-lake fishing, largely independent of Dimension 1 (r ≈ 0). This orthogonality suggests demographic and educational background shape angler profiles along an axis distinct from effort intensity, and that catch-oriented specialization (Dim1) does not map onto a single underlying respondent “type” together with age or education (Dim2). Broader patterns involving habitat type, additional age classes, and species-perception categories are detailed in the full variable summary (Supplementary Table S9), where several of these - including “lake,” “dam,” and mid-range age and education categories - showed moderate representation (0.20 < cos2 < 0.40) but did not meet the >10% contribution threshold used for Figure 3.
These results indicate that demographic structuring of angler subgroups (Dim2) is largely decoupled from effort-based specialization (Dim1), meaning interventions targeting one dimension - e.g., effort regulation for high-investment anglers - cannot be assumed to generalize across the age/education gradient captured by the other. Effective management is therefore likely to require distinct approaches tuned to each axis rather than a single behavioral or demographic lever.
Critically, 87.9% ± 2.1% of respondents perceived carp as having positive ecological roles, a perception contrasting with extensive scientific evidence documenting carp’s detrimental impacts on freshwater ecosystems (Weber and Brown, 2009; Vilizzi et al., 2015; Stuart et al., 2021). This discordance between angler perceptions and ecological reality underscores the risks of incorporating stakeholder opinions into management decisions without scientific validation (). However, it is worth noting that when discussing introduced species that have established viable populations for over 100 years, a phenomenon of cultural naturalization emerges, linked to ecological amnesia or a shifting baseline syndrome. This can, in fact, lead to the opposite paradox, where an introduced species becomes a protected species outside its original range (; ).
While respondents demonstrated WTP for fish community conservation and habitat protection, primarily selecting €50–100 lump-sum payments, such economic valuation does not address, and may inadvertently legitimize, the ecological damage caused by established non-native populations.
The habitat segregation observed along Dimension 1 - with river fishing associated with lower-effort, shorter-session profiles (Figure 3), and lake/dam habitats linked to higher-effort profiles in the broader ordination (Supplementary Table S9) - coupled with high mobility patterns (84.5% ± 2.3% traveling to fishing locations), raises concerns about anthropogenic pressures on freshwater ecosystems. Increased access to riparian zones elevates risks of bank degradation, soil compaction, pollution from vehicles and equipment, and habitat alteration, consequences documented for water-based recreation globally (; Schafft et al., 2021). These impacts compound the ecological disruptions attributable to carp themselves, creating synergistic degradation pathways that threaten native biodiversity and ecosystem functioning (Pejchar and Mooney, 2009).
4.4 Suggested recommendation for reconciling stakeholder perceptions with conservation priorities through adaptive management
Among the primary threats to fishing site conservation and fish fauna, respondents perceived poaching as the greatest, followed by lack of local and national interest while remarkably, non-native species ranked lowest (3.9% ± 1.3%). This threat-hierarchy further illustrates the perception-reality disconnect: anglers prioritize illegal harvest over the documented ecological impacts of established non-native species like carp themselves (). The emphasis on poaching, a legitimate conservation concern in many freshwater systems, suggests anglers frame threats through resource depletion rather than ecosystem functioning, reinforcing the necessity for education initiatives that bridge experiential knowledge with scientific understanding of non-native species impacts.
From a conservation perspective, effective freshwater management requires integrating diverse stakeholder perspectives, including recreational anglers, commercial fishers, indigenous communities, conservation organizations, and scientific experts, within participatory governance frameworks that prioritize data-driven decision-making over subjective perceptions (; Pope et al., 2016; Scheufele and Pascoe, 2022). While carp fishing demonstrably provides cultural ecosystem services (e.g., recreational opportunities, wellbeing enhancement, economic contributions), these benefits must be evaluated against the disservices imposed by non-native species on native biodiversity, water quality, and ecosystem functioning (; ; Rabaey et al., 2026; Sax et al., 2022; Yang et al., 2026).
Practical eradication of established carp populations across large spatial scales remains unrealistic given their fecundity, dispersal capacity, and population resilience (Stuart et al., 2021). Localized removals may succeed in small, isolated water bodies where ecological restoration holds priority, as demonstrated through selective harvesting, biocontrol research, and targeted removal strategies implemented internationally (; Poole and Bajer, 2019; ). However, broad-scale management necessitates pragmatic approaches balancing ecological integrity with socioeconomic realities.
We therefore advocate for adaptive co-management strategies that: (1) implement population control measures in ecologically sensitive areas prioritizing native species. These areas will be defined as AZN - Allocated Zone for Natives “A freshwater area designated for native species conservation priority, maintained not through physical isolation but through a recurring, risk-calibrated non-native control regime (e.g., harvest quotas, concentrated removal efforts), such that non-native suppression effort is sustained at a rate exceeding the reinvasion/recolonization pressure from the surrounding connected network.”; (2) designate zones where recreational carp fishing continues under regulated access to minimize habitat degradation; (3) develop transparent communication campaigns educating the population about carp’s ecological impacts while acknowledging legitimate recreational values, following successful European precedents (); (4) invest in long-term monitoring quantifying both ecosystem-service provisioning and disservice costs to inform evidence-based policy.
Ultimately, sustainable freshwater management demands honest acknowledgment that recreational preferences for non-native species exist within complex socio-ecological systems where human wellbeing and ecological integrity intersect imperfectly. Public participation in environmental decision-making remains essential for democratic legitimacy and social acceptance of conservation policies (). However, cautiousness and data-driven approaches must be preferred over perception alone when managing freshwater ecosystems for long-term ecological status improvement. Carps represent a non-native species complex that provides measurable ecosystem services yet simultaneously degrades freshwater habitats and threatens native biodiversity, a paradox requiring scientifically informed, adaptive management rather than stakeholder-driven perpetuation of ecologically harmful status quos. Proactive, evidence-based interventions guided by restoration ecology principles offer the most viable pathway toward reconciling human use with ecosystem functioning in freshwater systems increasingly stressed by multiple anthropogenic pressures.
Statements
Data availability statement
The raw data supporting the conclusions of this article will be made available by the authors, upon reasonable request.
Ethics statement
The requirement of ethical approval was waived by at the time of study design and data collection, there was no institutional research ethics committee requirement applicable to anonymous questionnaire-based social research of this type; therefore, no formal ethics approval was sought or required. Participants were informed about the aims of the research, the voluntary nature of their participation, the anonymity of their responses, and data storage and protection procedures. Informed consent was obtained from all participants prior to their participation, and consent was implied by their voluntary completion of the questionnaire. The studies were conducted in accordance with the local legislation and institutional requirements. Written informed consent for participation in this study was provided by the participants’ legal guardians/next of kin. Written informed consent was not obtained from the individual(s) for the publication of any potentially identifiable images or data included in this article because Participation in this survey is anonymous and voluntier. This survey has no commercial or advertising purposes but is purely scientific.
Author contributions
SP: Conceptualization, Data curation, Investigation, Methodology, Visualization, Writing – original draft, Writing – review and editing. MG: Methodology, Validation, Writing – original draft. PM: Methodology, Validation, Writing – review and editing. GC: Conceptualization, Resources, Supervision, Writing – review and editing.
Funding
The author(s) declared that financial support was not received for this work and/or its publication.
Acknowledgments
The authors sincerely thank all the participants that made this Research possible. Additional thanks to Luca Montanari (and colleagues) on behalf of Carp Parma 2025 Trade Show, staff and Brand/Team Leaders and collaborators, but also to Agostino Zurma, as President of Carp Fishing Italia (CFI) for the collaboration and spreading of the questionnaires among CFI’s subscribers. The author(s) would like to thank the Wildlife Sector (hunting, fishing and aquaculture) of the Emilia-Romagna Region’s General Directorate for Agriculture, Hunting and Fishing for their long-standing collaboration and support of research into the ecology of freshwater fish fauna.
Conflict of interest
The author(s) declared that this work was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
Generative AI statement
The author(s) declared that generative AI was not used in the creation of this manuscript.
Any alternative text (alt text) provided alongside figures in this article has been generated by Frontiers with the support of artificial intelligence and reasonable efforts have been made to ensure accuracy, including review by the authors wherever possible. If you identify any issues, please contact us.
Publisher’s note
All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.
Supplementary material
The Supplementary Material for this article can be found online at: https://www.frontiersin.org/articles/10.3389/fenvs.2026.1951159/full#supplementary-material
References
1
AgrestiA. (2007). An Introduction to Categorical Data Analysis, 2nd Edition, New York: John Wiley and Sons. 10.1002/bimj.4710290113
2
AkbariN.FaillerP.PanH.DrakefordB.ForseA. (2023). The impact of fisheries on the economy: a systematic review on the application of general equilibrium and input–output methods. Sustainability15 (7), 6089. 10.3390/su15076089
3
ArlinghausR.MehnerT. (2003). Socio-economic characterisation of specialised common carp (Cyprinus carpio L.) anglers in Germany, and implications for inland fisheries management and eutrophication control. Fish. Res.61 (1–3), 19–33. 10.1016/s0165-7836(02)00243-6
4
ArlinghausR.MehnerT.CowxI. G. (2002). Reconciling traditional inland fisheries management and sustainability in industrialized countries, with emphasis on Europe. Fish Fish.3 (4), 261–316. 10.1046/j.1467-2979.2002.00102.x
5
ArlinghausR.AlósJ.BeardmoreB.DaedlowK.DorowM.FujitaniM.et al (2017). Understanding and managing freshwater recreational fisheries as complex adaptive social-ecological systems. Rev. Fish. Sci. and Aquac.25 (1), 1–41. 10.1080/23308249.2016.1209160
6
ArrowK.SolowR.PortneyP. R.LeamerE. E.RadnerR.SchumanH. (1993). Report of the NOAA panel on contingent valuation. Fed. Register58 (10), 4601–4614. 10.1108/s0573-8555(1993)0000220017
7
BenediniM.RossiG. (2021). “Water resources of Italy,” in Water Law, Policy and Economics in Italy: Between National Autonomy and EU Law Constraints (Cham: Springer International Publishing), 3–31. 10.1007/978-3-030-69075-5_1
8
BirdsongM.BeardmoreB.DorowM.PagelT.ArlinghausR. (2025). Culture, context, and fish length drives voluntary catch-and-release behaviour of recreational anglers. Rev. Fish Biol. Fish.35, 1–28. 10.1007/s11160-025-09971-6
9
BryanH. (1977). Leisure value systems and recreational specialization: the case of trout fishermen. J. Leisure Research9 (3), 174–187. 10.1080/00222216.1977.11970328
10
BurginS. (2017). Indirect consequences of recreational fishing in freshwater ecosystems: an exploration from an Australian perspective. Sustainability9 (2), 280. 10.3390/su9020280
11
CarsonR. T. (2012). Contingent valuation: a practical alternative when prices aren't available. J. Economic Perspectives26 (4), 27–42. 10.1257/jep.26.4.27
12
ChenX.EvansT. G.JeschkeJ. M.GriffithP.JähnigS. C.HeF. (2026). Global assessment of alien freshwater megafauna reveals complex socio-economic impacts. One Earth9, 101623. 10.1016/j.oneear.2026.101623
13
ClaveroM. (2014). Shifting baselines and the conservation of non-native species. Conserv. Biol.28 (5), 1434–1436. 10.1111/cobi.12266
14
ClaveroM. (2022). The King's aquatic desires: 16Th‐Century fish and crayfish introductions into Spain. Fish Fish.23 (6), 1251–1263. 10.1111/faf.12680
15
ColvinM. E.PierceC. L.StewartT. W.GrummerS. E. (2012). Strategies to control a common carp population by pulsed commercial harvest. North Am. J. Fish. Manag.32 (6), 1251–1264. 10.1080/02755947.2012.728175
16
CookeS. J.I. CowxG. (2004). The role of recreational fishing in global fish crises. BioScience54 (9), 857–859. 10.1641/0006-3568(2004)054[0857:trorfi]2.0.co;2
17
CostanzaR. (2024). Misconceptions about the valuation of ecosystem services. Ecosyst. Serv.70, 101667. 10.1016/j.ecoser.2024.101667
18
CostanzaR.d'ArgeR.De GrootR.FarberS.GrassoM.HannonB.et al (1997). The value of the world's ecosystem services and natural capital. Nature387 (6630), 253–260. 10.1038/387253a0
19
CuthbertR. N.PattisonZ.TaylorN. G.VerbruggeL.DiagneC.AhmedD. A. L.et al (2021). Global economic costs of aquatic invasive alien species. Sci. Total Environment, 775: 145238. 10.1016/j.scitotenv.2021.145238
20
DaoT.ArlinghausR.EhrlichE.QuaasM. (2025). Adaptive fisher behavior alone can induce tipping points and stock collapse: a synthesis of bioeconomic theory that applies to all capture fisheries under open access. Rev. Fish. Sci. and Aquac.34, 1–40. 10.1080/23308249.2025.2549054
21
De KockS.GomelskyB. (2015). “Japanese ornamental koi carp: origin, variation and genetics,” in Biology and Ecology of Carp. Editors PietschC.Hirsch P. (CRC Press), 27–53.
22
DittonR. B.LoomisD. K.ChoiS. (1992). Recreation specialization: re-Conceptualization from a social worlds perspective. J. Leis. Res.24 (1), 33–51. 10.1080/00222216.1992.11969870
23
DruppM. A.HänselM. C.FenichelE. P.FreemanM.GollierC.GroomB.et al (2024). Accounting for the increasing benefits from scarce ecosystems. Science383 (6687), 1062–1064. 10.1126/science.adk2086
24
DudgeonD.ArthingtonA. H.GessnerM. O.KawabataZ. I.KnowlerD. J.LévêqueC.et al (2006). Freshwater biodiversity: importance, threats, status and conservation challenges. Biol. Rev.81 (2), 163–182. 10.1017/s1464793105006950
25
EllenderB. R.WeylO. L. F. (2014). A review of current knowledge, risk and ecological impacts associated with non-native freshwater fishes in South Africa. Aquat. Invasions9 (2), 117–132. 10.3391/ai.2014.9.2.01
26
ElwellT. L.GelcichS.GainesS. D.Lopez-CarrD. (2018). Using people's perceptions of ecosystem services to guide modeling and management efforts. Sci. Total Environ.637, 1014–1025. 10.1016/j.scitotenv.2018.04.052
27
EstévezR. A.AndersonC. B.PizarroJ. C.BurgmanM. A. (2015). Clarifying values, risk perceptions, and attitudes to resolve or avoid social conflicts in invasive species management. Conserv. Biol.29 (1), 19–30. 10.1111/cobi.12359
28
FAO (2024). The State of World Fisheries and Aquaculture 2024: Blue Transformation in Action. Rome: FAO. 10.4060/cd0683en
29
FedlerA. J.DittonR. B. (2001). Dropping out and dropping in: a study of factors for changing recreational fishing participation. North Am. J. Fish. Manag.21 (2), 283–292.
30
Fisheries Research and Development Corporation (2022). The National Carp Control Plan (NCCP). Deakin West, ACT. Canberra, ACT, Australia: National Carp Control Plan. Available online at: https://www.agriculture.gov.au/biosecurity-trade/pests-diseases-weeds/pest-animals-and-weeds/carp-biological-control-program (Accessed January 10, 2026).
31
GaglioM.LanzoniM.MuresanA. N.SchirpkeU.CastaldelliG. (2024). Quantifying intangible values of wetlands as instrument for conservation in the Po Delta park (italy). J. Environ. Manag.360, 121227. 10.1016/j.jenvman.2024.121227
32
GavioliA.FilipeA. F.PatonaiK.MilardiM.CastaldelliG. (2023). Effectiveness of the natura 2000 network for freshwater fish conservation in a mediterranean region. Front. Environ. Sci.11, 1122464. 10.3389/fenvs.2023.1122464
33
GenovesiP. (2007). Linee guida per la reintroduzione e il ripopolamento di specie faunistiche di interesse comunitario [Guide to reintroduction of species important from faunistic point of view]. Quad. Conserv. Nat.27, 1–51. (in Italian).
34
GhirardiN.BrescianiM.PinardiM.NizzoliD.ViaroliP. (2023). Pit Lakes from gravel and sand quarrying in the po river basin: an opportunity for riverscape rehabilitation and ecosystem services improvement. Ecol. Eng.196, 107103. 10.1016/j.ecoleng.2023.107103
35
HanemannW. M. (1994). Valuing the environment through contingent valuation. J. Economic Perspectives8 (4), 19–43. 10.1257/jep.8.4.19
36
HaubrockP. J.BerneryC.CuthbertR. N.LiuC.KourantidouM.LeroyB.et al (2022). Knowledge gaps in economic costs of invasive alien fish worldwide. Sci. Total Environ.803, 149875. 10.1016/j.scitotenv.2021.149875
37
HedgesS. B.MarinJ.SuleskiM.PaymerM.KumarS. (2015). Tree of life reveals clock-like speciation and diversification. Mol. Biol. Evol.32 (4), 835–845. 10.1093/molbev/msv037
38
HegedűsA.StasznyÁ.WeiperthA.BányaiZ.LenteV.UrbányiB.et al (2026). Characterization of management practices and ecological challenges of sustainable recreational fishery management in Hungary (central Europe). Rev. Fish Biol. Fish.36 (1), 2. 10.1007/s11160-025-10004-5
39
HowarthA.CookeS. J.NguyenV. M.HuntL. M. (2024). Non-probabilistic surveys and sampling in the human dimensions of fisheries. Rev. Fish Biol. Fish.34 (2), 597–622. 10.1007/s11160-023-09831-1
40
ImbertA.CucheroussetJ.ParthuisotN.BoulêtreauS. (2022). Elemental composition and microbial decomposition of different angling baits. Fish. Manag. Ecolology29 (5), 552–559. 10.1111/fme.12537
41
Istituto Zooprofilattico Sperimentale delle Venezie (IZSVe), e Associazione Piscicoltori Italiani (API) (2025). Manuale sul benessere per le specie ittiche allevate. Guida per l’operatore. Legnaro (PD): IZSVe. Available online at: https://www.izsvenezie.it/manuale-benessere-specie-ittiche/ (Accessed January 10, 2026).
42
ItticoBMTI (2023). CARPA - ANALISI ECONOMICA E PROSPETTIVE DI CONSUMO. Available online at: https://ittico.bmti.it/CaricaPdfRegolamenti.do?doc=11 (Accessed January 10, 2026).
43
JamesG.WittenD.HastieT.TibshiraniR. (2013). An Introduction to Statistical Learning: With Applications in R, 103. New York: Springer. 10.1007/978-1-4614-7138-7_2
44
KumarP. (2012). The economics of ecosystems and biodiversity: ecological and economic foundations. Abingdon, United Kingdom: Routledge. 10.4324/9781849775489
45
LoweS.BrowneM.BoudjelasS.De PoorterM. (2000). 100 of the World's Worst Invasive Alien Species: A Selection from the Global Invasive Species Database. Auckland: Invasive Species Specialist Group.
46
McDanielsT. L.AxelrodL. J.CavanaghN. S.SlovicP. (1997). Perception of ecological risk to water environments. Risk Anal.17 (3), 341–352. 10.1111/j.1539-6924.1997.tb00872.x
47
MenardS. (2001). Applied Logistic Regression Analysis. 2nd ed. Thousand Oaks, CA: SAGE publications. 10.4135/9781412983433
48
MilardiM.LanzoniM.KiljunenM.TorniainenJ.CastaldelliG. (2015). Natural recruitment contributes to high densities of grass carp Ctenopharyngodon idella (valenciennes, 1844) in Western Europe. Aquat. Invasions10 (4), 439–448. 10.3391/ai.2015.10.4.07
49
MilardiM.SoanaE.ChapmanD.FanoE. A.CastaldelliG. (2020). Could a freshwater fish be at the root of dystrophic crises in a coastal lagoon?Sci. Total Environ.711, 135093. 10.1016/j.scitotenv.2019.135093
50
MilardiM.IemmaA.WaiteI. R.GavioliA.SoanaE.CastaldelliG. (2022). Natural and anthropogenic factors drive large-scale freshwater fish invasions. Sci. Rep.12 (1), 10465. 10.1038/s41598-022-14556-5
51
MohammedH. H.EbrahimM.YoussefM. I.SaleemA. S. Y.AbdelkhalekA. (2024). Behavior and management of carp fish: a review. Open Veterinary J.14 (1), 1. 10.5455/ovj.2024.v14.i1.1
52
Morales-NinB.ArlinghausR.AlósJ. (2025). Gender differences in participation rate, socioeconomic profile, recreational motivation, and wildlife-related value orientation among recreational Fishers in Spain. Fish. Res.285, 107363. 10.1016/j.fishres.2025.107363
53
MossoneP. (2019). Can the economic valuation of the environment be considered a problem of individual choice. J. Aquatic Res. Mar. Sci., 2019, 121–124. 10.29199/arms.103028
54
OttburgF.BlankM. (2015). “Solutions to the impacts of roads and other barriers on fish and fish habitat,” in Handbook of Road Ecology. Editors van der ReeR.SmithD. J.Grilo C. (Wiley) 364–372. 10.1002/9781118568170.ch45
55
O’TooleA. C.HansonK. C.CookeS. J. (2009). The effect of shoreline recreational angling activities on aquatic and riparian habitat within an urban environment: implications for conservation and management. Environ. Management44 (2), 324–334. 10.1007/s00267-009-9299-3
56
PagèsJ. (2004). Analyse factorielle de données mixtes. Rev. Stat. appliquée52 (4), 93–111.
57
PejcharL.MooneyH. A. (2009). Invasive species, ecosystem services and human well-being. Trends Ecol. Evol.24 (9), 497–504. 10.1016/j.tree.2009.03.016
58
PitaP.TraceyS.ArlinghausR.BachillerE.Pinho-DuarteF.FerterK.et al (2025). Staying hooked: effective science engagement and communication in recreational fisheries. Front. Mar. Sci.12, 1589544. 10.3389/fmars.2025.1589544
59
PooleJ. R.BajerP. G. (2019). A small native predator reduces reproductive success of a large invasive fish as revealed by whole-lake experiments. PloS One14 (4), e0214009. 10.1371/journal.pone.0214009
60
PooleJ. R.SaueyB. W.AmbergJ. J.BajerP. G. (2018). Assessing the efficacy of corn-based bait containing antimycin-a to control common carp populations using laboratory and pond experiments. Biol. Invasions20 (7), 1809–1820. 10.1007/s10530-018-1662-y
61
PopeK. L.PeggM. A.ColeN. W.SiddonsS. F.FedeleA. D.HarmonB. S.et al (2016). Fishing for ecosystem services. J. Environ. Manag.183, 408–417. 10.1016/j.jenvman.2016.04.024
62
R Core Team (2022). R: A Language and Environment for Statistical Computing. Vienna: R Foundation for Statistical Computing. Available online at: https://www.R-project.org/ (Accessed June 30, 2026).
63
RabaeyJ. S.HuserB. J.DowningJ. A. (2026). Invasion of common carp (Cyprinus carpio) reduces the quality of bottom sediments in shallow Lakes. Water Res.292, 125316. 10.1016/j.watres.2025.125316
64
SaxD. F.SchlaepferM. A.OldenJ. D. (2022). Valuing the contributions of non-native species to people and nature. Trends Ecol. Evol.37 (12), 1058–1066. 10.1016/j.tree.2022.08.005
65
SayerC. A.FernandoE.JimenezR. R.MacfarlaneN. B.RapacciuoloG.BöhmM.et al (2025). One-quarter of freshwater fauna threatened with extinction. Nature638 (8049), 138–145. 10.1038/s41586-024-08375-z
66
SbragagliaV.ArlinghausR.Ochwada‐DoyleF.EmbkeH. S.GriffinL. P.HuntT. L. (2025). Three decades of world recreational fishing conferences: what have we learned about the dynamics of recreational fisheries?Fish. Manag. Ecol.32, e12815–10. 10.1111/fme.12815
67
SchafftM.WegnerB.MeyerN.WolterC.ArlinghausR. (2021). Ecological impacts of water-based recreational activities on freshwater ecosystems: a global meta-analysis. Proc. R. Soc. B Biol. Sci.288 (1959), 20211623. 10.1098/rspb.2021.1623
68
ScheufeleG.PascoeS. (2022). Estimation and use of recreational fishing values in management decisions. Ambio51 (5), 1275–1286. 10.1007/s13280-021-01634-7
69
ScheufeleG.BurtonM.PanditR. (2025). On the importance of discrete choice experiment framings to derive accounting values for ecosystem and species appreciation services. Ecosyst. Serv.74, 101745. 10.1016/j.ecoser.2025.101745
70
SongW.LinL.OhS.GrossartH. P.YangY. (2025). Tire wear particles in aquatic environments: from biota to ecosystem impacts. J. Environ. Manag.388, 126059. 10.1016/j.jenvman.2025.126059
71
SotoI.BalzaniP.CarneiroL.CuthbertR. N.MacêdoR.TarkanA. S.et al (2024). Taming the terminological tempest in invasion science. Biol. Rev.99, 1357–1390. 10.1111/brv.13071
72
StuartI. G.FansonB. G.LyonJ. P.StocksJ.BrooksS.NorrisA.et al (2021). Continental threat: how many common carp (Cyprinus carpio) are there in Australia?Biol. Conserv.254, 108942. 10.1016/j.biocon.2020.108942
73
TarkanA. S.MarrS. M.EkmekçiF. G. (2015). Non-native and translocated freshwater fish. FiSHMED Fishes Mediterr. Environ.3, 1–28. 10.29094/FiSHMED.2015.003
74
van der HammenT.ChenC. (2020). Participation rate and demographic profile in recreational angling in the Netherlands between 2009 and 2017. Fish. Res.229, 105592. 10.1016/j.fishres.2020.105592
75
VaskeJ. J. (2019). Survey Research and Analysis, 2nd edn. Sagamore-Venture Publishing LLC, Urbana.
76
VaskeJ. J.NeedhamM. D.MillerC. A. (2025). “Fundamentals of sampling and implementing human dimensions of fishing surveys,” in Understanding Recreational Fishers: Disciplinary and Interdisciplinary Approaches for Fisheries Management (Cham: Springer Nature Switzerland), 327–353. 10.1007/978-3-031-99739-6_11
77
VazquezK.JohnsonJ. C.GriffithD.MuneepeerakulR. (2024). Exploration of underlying patterns among conflict, socioeconomic and political factors. Plos One19 (5), e0304580. 10.1371/journal.pone.0304580
78
VilizziL.TarkanA. S.CoppG. H. (2015). Experimental evidence from causal criteria analysis for the effects of common carp Cyprinus carpio on freshwater ecosystems: a global perspective. Rev. Fish. Sci. and Aquac.23 (3), 253–290. 10.1080/23308249.2015.1051214
79
VitousekP. M.d’AntonioC. M.LoopeL. L.WestbrooksR. (1996). Biological invasions as global environmental change. Am. Scientist84 (5), 468–478.
80
VoltaP.OggioniA.BettinettiR.JeppesenE. (2011). Assessing Lake typologies and indicator fish species for Italian natural Lakes using past fish richness and assemblages. Hydrobiologia671 (1), 227–240. 10.1007/s10750-011-0720-6
81
WalderJ.van der SpiegelA. (1990). Education for fisheries managers in the Netherlands. In: Proceedings of the Symposium on Management of Freshwater Fisheries, European Inland Fisheries Advisory Commission, Göteborg, Schweden, May 31–June 3, 1988. Pudoc, Wageningen, pp. 372–381.
82
WarziniackT.HaightR. G.YemshanovD.ApriesnigJ. L.HolmesT. P.CountrymanA. M.et al (2021). “Economics of invasive species,” in Invasive Species in Forests and Rangelands of the United States: A Comprehensive Science Synthesis for the United States Forest Sector (Cham: Springer International Publishing), 305–320.
83
WeberM. J.BrownM. L. (2009). Effects of common carp on aquatic ecosystems 80 years after “carp as a dominant”: ecological insights for fisheries management. Rev. Fish. Sci. and Aquac.17 (4), 524–537. 10.1080/10641260903189243
84
YangH.HaubrockP. J.BrittonJ. R.TarkanA. S.JeppesenE.GalibS. M.et al (2026). Recreational fishing drives the global spread of aquatic non-native species. 10.32942/x25d6k
Summary
Keywords
carp angler’s dimension, carps, cultural ecosystem services, freshwater management, global invader species, recreational fisheries, socio-ecological indicators
Citation
Pagani S, Gaglio M, Mossone P and Castaldelli G (2026) Carp angling: potential cultural ecosystem services and angler perceptions of a non-native species in Italy. Front. Environ. Sci. 14:1951159. doi: 10.3389/fenvs.2026.1951159
Received
28 July 2026
Revised
04 September 2026
Accepted
07 September 2026
Published
30 September 2026
Volume
14 - 2026
Edited by
Riccardo Fornaroli, University of Milano-Bicocca, Italy
Reviewed by
Alice Stocco, Ca’ Foscari University of Venice, Italy
Judicael Regis Kema Kema, Omar Bongo University, Gabon
Updates
Copyright
© 2026 Pagani, Gaglio, Mossone and Castaldelli.
This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
*Correspondence: Mattias Gaglio, gglmts@unife.it
Disclaimer
All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher.