1. Introduction
Capture fisheries and aquaculture (farming of aquatic organisms, including animals and plants) can, just as other food production sectors, negatively impact aquatic and terrestrial ecosystems, e.g., through overfishing (fisheries for human consumption and for aquatic oils and proteins used in animal feeds), eutrophication due to the release of excess nutrients, feed production and the spread of invasive species and diseases [
1,
2,
3]. Such adverse environmental and social impacts have together with a perceived failure of regulatory mechanisms (e.g., implementation of national legislation and codes of conduct to improve the sector) largely driven the development of seafood eco-certification programs. During the last decade, the number of eco-labeled seafood products available on European and North American markets has increased substantially [
4]. While there has been a rapid development of certification initiatives for seafood, the eco-certified share of global seafood production remains small [
4,
5]. A further increase is conceivably dependent on consumers’ demand for labeled products, and consumers are therefore key actors in market-based efforts aiming at improving the performance of the seafood sector.
As the number of certification schemes for seafood is growing, so is the body of literature analyzing consumers’ perceptions of, and willingness to pay for, eco-labeled seafood. The majority of studies have focused on capture fisheries and only a few on farmed seafood [
6]. Earlier work has either: (a) applied an experimental approach using contingent valuation to estimate consumers’ willingness to pay for eco-labeled seafood [
7,
8,
9,
10]; (b) examined consumers’ attitudes towards eco-labeling of seafood [
11,
12,
13]; (c) more generally explored the perceived importance of sustainability and ethics related to seafood [
14,
15]; or (d) used market data to investigate whether there is a price premium for eco-certified seafood [
16,
17]. While this work has substantially increased our understanding of what factors predict willingness to purchase sustainable seafood, to our knowledge, no study has yet investigated how consumers’ self-reported purchasing behavior of eco-labeled seafood is correlated with environmental knowledge and other internal factors expected to predict pro-environmental consumption. This study addresses this gap or knowledge deficit using consumer data from Stockholm, Sweden. First, we investigated the level of consumer knowledge regarding environmental impacts of seafood production and production practices (both aquaculture and capture fisheries) and the main sources of information used by consumers. Second, we assessed the relative importance of key personal characteristics predicted to be essential for pro-environmental consumer behavior to identify the most crucial internal barriers for increased demand for eco-labeled seafood. Sweden is a particularly interesting case since the market for eco-labeled food can be considered relatively mature [
18,
19] (the sales value of organic food reached more than seven percent by 2015 [
20]), and Swedish consumers generally show positive attitudes towards eco-labeled food products [
21].
3. Results
The first three parts of the Results
Section 3.1,
Section 3.2 and
Section 3.3 provide descriptive statistics of the stated purchasing of eco-labeled seafood, respondents subjective and objective knowledge along with PCE, self-identification and level of concern. Except for ‘source of environmental information’ (
n = 396), 406 respondents were represented in the descriptive statistics. In
Section 3.4, the results from the statistical analysis (MMI) are presented (
n = 371). The smaller sample size is due to several ‘don’t know’ responses in the large sample (
n = 406), not possible to include in the statistical analysis.
3.1. Respondents and Seafood Purchasing
The majority of the respondents purchased seafood in grocery stores at least once per week (41%) or per month (49%). A minority (16%) stated that they always buy eco-labeled seafood when available, whereas 68% reported to sometimes purchase eco-labeled seafood (3–4 on a five-point scale). The average rate (1–5) of stated purchasing of eco-labeled seafood was 3.43 (±1.00) (SD).
3.2. Objective and Subjective Knowledge
Most participants (78%) perceived themselves to have a low or moderate level of knowledge (1–3 on a five-point scale) pertaining to production of seafood (average 2.5 ± 1.23). The objective knowledge question with the highest rate of correct answers related to northern prawns, followed by a question about farming of tropical shrimp (
Table 3). None of the eight questions had a correct response rate above 74%, indicating a fairly low level of factual knowledge related to seafood production.
The level of recognition and perceived understanding of labels was for the majority of eco-labels low to moderate (
Table 4). The one exception was the Swedish KRAV label, which 94% of the respondents recognized. The most common eco-label for seafood on the Swedish market at the time of writing was the MSC label, solely recognized by 44% of the respondents and understood by 13%. Interestingly, 17% (more than one out of six) of the respondents stated that they recognized the fake label, implying that the actual level of recognition and understanding of the labels might be lower than as indicated by the results.
The main source of information (4–5 on a five-point scale) was media (55%), followed by environmental NGOs (40%) and friends/colleagues (36%). The information sources least accessed were retailers (7%) and fishermen/farmers (10%).
3.3. Environmental Concern and Pro-Environmental Self-Identification
More than half of the respondents (57%) stated that they feel worried about negative environmental impacts related to seafood production (4–5 on a five-point scale), and 44% perceived themselves to be environmentally conscious (4–5 on a five-point scale). The majority (63%) stated a high level (4–5 on a five-point scale) of PCE. Authorities (through provision of information), the government and seafood companies were identified to have the highest responsibility for sustainable seafood production, whereas consumers were stated as having the least responsibility (only 23% of the respondents rated the consumer responsibility as very high, i.e., five on a five-point scale).
3.4. Statistical Results
A total of 371 surveys were completed with respect to all nine variables included in the full model. Prior to conducting the multiple linear regression and MMI, multicollinearity between variables was tested for (VIF < 2). The full model containing all nine independent variables explained 25.4% of the variation in stated purchasing behavior of eco-certified seafood (adjusted
R2). Multi-model inference yielded 512 candidate models. A total of eleven models exhibited ΔAICc < 2 and accounted for 43% of the total AIC weights (
Table 5). The best model contained the variables
labels,
concern,
identity,
PCE,
obj. knowledge and
responsibility and had an AIC weight of 6%. Models including one of the factors
labels or
concern accounted for 100% of the cumulative weight of all of the 512 possible models, indicating a substantial importance of these two variables.
Identity and
PCE (accounting for 91% and 78% of cumulative weight, respectively) were also included in the majority of the high weight models and can thus also be considered relevant (
Figure C1,
Appendix C).
The evidence ratio for a particular model demonstrates the strength of evidence compared with the best model. The results from this study showed that the evidence for Model 1 is 2.6-times stronger than for Model 11 (
Table 5). To illustrate the interpretation procedure, we removed the top three most important variables (
labels,
concern and
identity) from the best model. The evidence ratios of the new models increased by a factor between six and 27,116, indicating the relative importance of each of the explanatory factors removed (
Table 6). Another interpretation exercise was to include only the top two variables (
concern and
labels) in a model. This gave a ΔAICc of 11.6, corresponding to an evidence ratio of 329, implying that the model is 329-times less likely than the best model. When
identity was added to this model (containing
concern and
labels), the evidence ratio increased to six (
Table 6), substantially improving the model fit and providing substantial support for the conclusion that
labels,
concern and
identity were the three most important variables in explaining stated purchasing behavior of eco-labeled seafood among consumers in Stockholm.
We further multiplied the standardized β-coefficients for the variables included with the weight of each individual model to get model averaging. This measure provided information on the predictive power of each explanatory variable included in the original model. The result (including shrinkage) is presented in
Figure 2. For more information on the multimodel averaging step and shrinkage, see
Appendix B.
Concern and
labels were the two variables with highest explanatory power (β = 0.24 and 0.23, respectively), followed by
identity and
PCE (β = 0.12 and 0.08, respectively).
A linear multiple regression analysis including the variables in the best model (
labels +
concern +
identity +
PCE +
obj. know. +
responsibility) was conducted as part of the MMI step in order to obtain information on which variables are statistically significant.
Labels and
concern (
p < 0.01), as well as
identity and
PCE (
p < 0.05) were the statistically-significant variables in the model (and also the variables with the highest model averaged effect sizes;
Figure 2). The adjusted
R2 value for the full model was 0.26.
4. Discussion
The first aim of this study was to assess the level of consumer environmental knowledge pertaining to aquatic food production systems and to investigate which sources of information that are most frequently used. The limited level of knowledge about seafood production systems and environmental impacts from capture fisheries and aquaculture found in this study agrees with results from earlier work, e.g., [
12,
63,
64]. The extent of label recognition differed substantially between logos presented, ranging from 95% for the organic label KRAV to only 23% for ASC. Noteworthy is the rather low level of recognition of the MSC label (43%), the largest seafood eco-label in Sweden. However, the results are consistent with earlier investigations of familiarity with the MSC label in Sweden (45%) [
65] and higher than the average of consumers from 15 countries (33%) [
66]. Since label recognition was one of the most important variables in predicting stated purchasing of eco-labeled seafood, we suggest that efforts need to be directed towards increasing consumers’ familiarity and understanding of seafood eco-labels. Retailers could potentially play a key role when it comes to the provision of information for two reasons: first, because they offer an arena where consumers are likely to be susceptible to information while making purchasing decisions [
67]; and second, retailers were, together with seafood producers, stated as the least important provider of environmental information pertaining to seafood production (average 1.9 ± 1.0 on a five-point scale), indicating room for improvement. However, it should be noted that the reason for the low use of retailers as a source of information is unknown and that lack of trust for commercial actors might be a barrier for consumer awareness making. Media and environmental NGOs (stated to be the most frequently-used sources of information, also supported by [
68]) are other potentially important actors in increasing consumers’ familiarity with seafood eco-labels.
The second objective of this study was to investigate the relative importance of internal factors (i.e., consumer characteristics) predicted to affect purchasing of eco-labeled seafood. The findings support the hypothesis that cognitive (
labels), as well as emotional (
concern) elements predict consumers’ stated purchasing behavior of eco-labeled seafood products. While the negative framing of the question on the degree of consumer concern may lead to a slight bias towards an expressed worry among respondents, a certain framing is inevitable and is not judged to have any substantial impact on the results. Awareness of action strategies has been highlighted in the literature as an important cognitive predictor for pro-environmental behavior [
37,
45]. We argue that for most consumers, choosing eco-labeled alternatives is the most feasible action strategy, although other approaches, such as seafood recommendation lists, are also viable alternatives [
69]. Our results show that recognition of eco-labels for seafood (together with concern for negative environmental impacts) constitutes the variable that most strongly influences respondents’ stated purchasing of eco-labeled seafood. This result supports recent findings where recognition and understanding of eco-labels for food products was positively correlated with label use [
70]. Our results also corroborate findings from earlier work stressing that concern for environmental impacts from seafood production is positively correlated with stated purchasing of eco-labeled seafood [
6,
10,
12]. Level of concern was weakly, yet significantly, positively correlated with recognition of seafood eco-labels (linear regression,
R2 = 0.06,
p < 0.01). Grunert et al. [
70] similarly found a weak positive correlation between concern about sustainability issues (environmental and social) related to food production and use of information provided by sustainability labels.
Though concern and awareness of eco-labels were the two most important variables predicting stated purchasing of eco-labeled seafood, two other internal factors were also highly relevant.
Identity and
PCE both predicted significant effects on stated purchasing of eco-labeled seafood in the best model. The importance of the predictors self-identification and membership in an environmental organization (here, captured by
identity) has been identified in previous work [
8,
28]. Perceived consumer effectiveness (
PCE) was the fourth most important variable in predicting stated purchasing behavior and is likely an important component of the decision making process, since it implies a perception that the individual’s actions are of significance. There was little evidence in our findings that demographic variables had an effect on stated purchasing of eco-labeled seafood. The lack of relationship between gender or level of education and pro-environmental behavior is in line with earlier research showing limited effects of demographic factors [
71]. However, it contrasts with work showing that female and well-educated consumers are more prone to buy eco-labeled seafood alternatives than are other people [
12,
13,
72].
Limited knowledge on how food is produced and the environmental implications of production has been conceptualized as food illiteracy [
73] and could constitute a barrier for sustainable food consumption. Though the results from this study showed that objective environmental knowledge is a comparatively weak predictor of stated purchasing of eco-labeled seafood, there appears to be an association between the cognitive and emotional components of consumer decision making [
74]. Provision of environmental knowledge may induce an emotional response stimulating pro-environmental behavior [
75], and the other way around, an individual who is emotionally engaged might be more prone to search for knowledge in order to learn more about how food is produced and the environmental effects of production practices (both positive and negative) [
76]. The link between subjective knowledge pertaining to marine environmental impacts and level of concern has been highlighted in recent research [
68], supporting the association between self-identification and emotional engagement. The level of subjective knowledge in this study is consistent with earlier work dealing with seafood consumers’ self-stated level of knowledge (e.g., [
14]). However, in contrast to work by [
23,
25], the results from multi-model averaging indicate that objective knowledge is a better predictor of eco-labeled seafood purchasing than subjective knowledge. Worth noting, however, is that both variables (
obj. knowledge and
subj. knowledge) were weak predictors of eco-labeled seafood purchase compared with other variables.
The average frequency of stated purchasing eco-labeled seafood in this study was 3.43 ± 1.00 (mean ± SD) on a five-point scale, indicating that the majority of respondents state that they sometimes choose an eco-labeled seafood alternative when available. Important to note here is that 39% of the yearly sales value (2013/2014) of frozen seafood in Sweden currently is eco-labeled by the MSC, and 2% is labeled as organic [
77]. Some of the respondents participating in this study might thus choose eco-labeled seafood unintentionally, but state otherwise in the questionnaire. It is, however, worth considering that a relatively small proportion of farmed and fresh seafood (both farmed and wild-caught) is eco-labeled in Sweden. This should be viewed in the context of two clear trends in Swedish seafood retailing: (a) that the demand for salmon (by the time of writing, the most popular seafood), of which the great majority is farmed, has increased substantially in the last few years (34% increase in the volume sold between 2010 and 2012); and (b) that the demand for fresh seafood has increased at the expense of frozen, conserved and canned seafood [
78]. The results of this work could therefore be of interest for actors aiming to shift farmed and fresh seafood consumption (as well as non-labeled wild-caught frozen seafood) towards improved sustainability.
The relatively low explanatory power of the best linear regression model generated by MMI (adjusted
R2 0.26) indicates that additional factors, most likely external, e.g., price and availability, influence whether consumers choose to buy eco-labeled seafood alternatives. Internal factors not specifically measured in this study, e.g., positive feelings of purchasing labeled alternatives, could also affect the demand for eco-labeled seafood. Given the potential existence of an intention-behavior gap [
39], a possible weakness of this study is that the measure for sustainable seafood consumption was restricted to individuals’ stated behavior and not complemented by figures on revealed preferences, e.g., market observations or experimental data. Moreover, we acknowledge that using Stockholm and Sweden as a case may limit the applicability of results to regions where the interest for ethical consumption is relatively high. However, on the other hand, results from this study pointing towards a low level of awareness of negative environmental impacts and seafood eco-labels among consumers in presumably one of the most pro-environmental consumption-oriented markets in the world are likely of relevance for the sustainable seafood movement as a whole. While this study investigated factors influencing stated purchasing of eco-labeled seafood, we recognize that consumer demand is only one out of many potential drivers towards increasing the share of eco-certified seafood on global markets and enhancing the environmental sustainability of the seafood sector. Other mechanisms (e.g., consumer choice editing by retailers and wholesalers, implementation of legislation and code of conducts for production) are also highly relevant, particularly in emerging economies where pro-environmental consumption is a relatively recent and immature phenomenon.