The socio-ecological approach has been widely used by several theorists of Human Ecology and Theory of commons  for the study and conservation of terrestrial, marine, and estuarine-lagoon ecosystems [2, 3], and the cultural diversity associated with these environments . Because of human occupancy and use, estuarine-lagoon systems are socio-ecological systems , making them an integral part of lagoon ecology and its cycles . A socio-ecological co-evolution approach is needed to understand ecosystem processes, which involve the accumulation of individual and collective knowledge about the ecosystem contained in “social memories” . Knowledge about ecosystems has accompanied mankind for thousands of years and through numerous environmental changes and cultural adaptations . According to Toledo and Barrera-Bassols (2008), so-called traditional populations are heirs of historical experiences marked by the encounter between biological and cultural realms, and these experiences construe traditional ecological knowledge (TEK). On the other hand, modern society is dominated by its inability to remember immediate, medium-term, and long-range historical processes .
New studies in ethnography (or ethnoscience) have shown, since its emergence in the 1950’s, that TEK is an important source of information for the understanding of ecological processes [3, 8, 9]. Among those who study TEK, there are, in general, two tendencies: the followers of the complementarity/integration theory [10, 11] and the followers of the “cultures meeting” theory [4, 9, 12–15]. The first group claims that TEK must be integrated with SK to provide insights into ecological research (biogeography, phylogeny, systematics, ethnology, population genetics, ecosystem management, etc.) , and have its likelihood strictly tested against reality . Within this first proposal, TEK is complementary (selectively integrated) to SK, which is considered the ultimate reality against which the traditional is measured . The second group proposes TEK as an alternative to Western scientific rationality [4, 12], which may be linked to SK , and used to question  and transform it. In the second proposal, there is an acknowledgement of the need to change the SK paradigm, and integrate TEK, so that our “amoral, positivist society” becomes an “ethical, holistic society” (: 1270).
In line with the second observed trend, a “swarm of researchers” has made a countercurrent intellectual effort to register, analyze, and reassess the TEK of traditional populations . Several priority TEK fields of investigation have been identified, such as ethnotaxonomy , the unity and diversity of indigenous knowledge systems , ethno-habitats, species migration and reproduction patterns, climate, navigation and fishing skills , relations with the supernatural world , and the traditional management of natural resources .
Despite the great advancements in ethnosciences since the 1960’s and in research using TEK, starting from its naming and concept formation in the 1980’s [7, 19], there are still several problems to be solved and questions to be answered. Among the problems noted in the scientific literature the following can be highlighted: romanticism in the use of TEK, the simplistic dichotomization between SK and TEK , the variability of analytical concepts used (TEK, traditional knowledge, local ecological knowledge, indigenous knowledge, etc.) [8, 21] fragmentary TEK descriptions , and the application of academic logic to traditional populations . One question unanswered question often cited in the literature, concerns the application of TEK to present “resource management scenarios” (: 06, [3, 8, 19, 21]). Some vague notes on how to apply TEK to these situations include the use of TEK as a source of biological information as well as a data source on local ecosystems . Other studies acknowledge that SK and TEK are based on similar principles and are not incompatible. Also noted is the possibility for overcoming the narrowness of species-level management, commonly used in science, and the possibility of working toward an ecosystemic management approach similar to the management practiced by traditional populations .
This article discusses another possible and little explored solution: the incorporation of traditional time based on TEK in the construction of a local resource management scenario. Research for this case study was conducted is the Patos Lagoon estuary, located in the southernmost portion of Brazil. Despite several efforts in the study of traditional time see [23–27], these discussions fail to describe the historical see [28, 29] and present importance of time control see  as both a tool for social control and an instrument of power. In the regulation of fishing activities, time control has been a systematic practice in management guided by conventional scientific knowledge—by prohibiting fishing during certain seasons of the year (season closures) see . The restriction of time has been a systematic practice adopted by the Brazilian government in an attempt to manage fish resources by applying the so-called “closed fishing season” (see [31, 32]).
The state of Rio Grande do Sul (RS), Brazil comes to the scene in the context of time control with the emergence of successive Normative Rulings, which have regulated the management of fishing resources in the Patos Lagoon estuary since the beginning 1970’sa. The 2004 Joint Normative Ruling (INC 2004)b presently regulates fishing in the estuary. Among other regulations, INC 2004 imposes a fishing calendar for pink shrimp in the Patos Lagoon estuary. According to Kalikoski (2002), with the creation of the Forum of the Patos Lagoon (FPL), the pink shrimp fishing calendar was fashioned on the basis of scientific knowledge, and has engendered conflicts between government institutions and artisanal fisherman . At the same time, selection and appropriation of fish criteria made by governmental institutions in the FPL differed from scientific recommendations. The selection and appropriation process of scientific knowledge by governmental institutions (such as the Ministry of the Environment (Ministério do Meio Ambiente - MMA) and Ministry of Fish and Acquaculture - Ministério da Aquicultura e Pesca e Aquacultura - MPA) guiding fishing activities is a subject for future research. In this paper, we emphasize the incorporation of traditional time in the construction of a management scenario for pink shrimp in the Patos Lagoon estuary (RS), Brazil.
The discussion of the construction of a “resources management scenario” will be done in five steps—the first two being presented in the results section and the others in the discussion section. The steps are presented as the following: 1 - Describes SK and TEK of the pink shrimp life cycle in the Patos Lagoon estuary; 2 - Describes pink shrimp management recommended by SK, and traditional pink shrimp management based on TEK, with time/calendar as an underlying analytical category; 3 - Emphasizes and defines the (in)congruencies between SK, upon which the calendar imposed by INC 2004 is based, and TEK, which is the basis for the traditional calendar/time of artisanal fishers in the estuary—both referring to the pink shrimp migration cycle in the Patos Lagoon estuary; 4 - Stresses and defines the (in)congruencies between SM and TM of pink shrimp in the Patos Lagoon estuary with time/calendar as an underlying analytical category; 5 - Based on the “cultural meeting” of different forms of knowledge, ways of management, and conceptions of time, some guidelines will be established for the construction of a possible local management scenario for pink shrimp.
In the first four sections, we will describe and discuss the observed (in)congruencies among SK and TEK and both the scientific and the traditional calendar for managing fish resources. Thus, we will test the hypothesis that knowledge and management strategies for fishing resources are incommensurable.
There are some authors, such as Menzie and Butler (2006), who call it unproductive to compare SK and TEK through the “incommensurability perspective” because it is arguably a simplistic comparison and can masquerade important “similarities” . In this article, we shown that the “incommensurability” thesis is necessary to discuss at which level the (in)congruencies appear and, from here reveal what is claimed by Menzie and Butler (2006: 06) as: “The principles underlying TEK and science (that) hold similar observational principles”, which will be considered “criteria for hierarchies of validity” (: 98) in the construction of a “resource management scenario” (: 06). Santos et al. (2005) argues that no human practice could be possible if different kinds of knowledge had equal weight. Thus, from a pragmatic viewpoint, the relativism issue has a bearing on “criteria for hierarchies of validity” to solve the “epistemological problem” and make human practice possible . In this case study, “criteria for hierarchies of validity” will be formulated at commensurable level(s) in order to enable the construction of “resources management scenarios;” without these criteria, such “scenarios” and management practices in such scenarios would be impossible.
Therefore, in agreement with Leff (2001), it can be understood that the incommensurability hypothesis is necessary to delimit new arrays of environmental rationality for the use of natural resources . In this sense, the incommensurability hypothesis puts into action the discussion and analysis of the dialog between TEK and SK, as it does for scientific management and traditional management; and the “criteria for hierarchies of validity” provides support for the construction of a “resources management scenario”.
Time as traditional ecological knowledge (TEK)
The basic function of any knowledge system is to organize the world . Knowledge interferes in the whole process of the significance of the world and appropriation of nature . From his work on popular classification systems in the 1970’s, Levi-Strauss (1976) has discussed two general ways in which scientific thinking puts the world in order: the first approximates sensitive intuition and the other is further from this intuition. The first is the practical knowledge of traditional people, or the “concrete science”, and the second is modern science .
In the last 50 years since the scientific panorama of the 1960’s, several definitions, naming, and thought trends have emerged in the study of the “science of the concrete”. Among the denominations used in the wider literature, the following terms can be found: “oral tradition”, “indigenous knowledge”, “local knowledge”, “community knowledge” , “traditional knowledge”, “traditional ecological knowledge”  and “ecological knowledge” . To reach the goal of investigating the (in)congruencies between SK and artisanal fishers’ knowledge on the pink shrimp migration cycle in the Patos Lagoon estuary, we find the term “traditional ecological knowledge” (TEK) most adequate because: 1 - it clearly distinguishes its investigation domain, that is, nature [7, 8]; 2 - it involves the perception of traditional populations about their environmental systems and how they influence and are affected by natural processes ; 3 - although it is not schooled by the conventional scientific paradigm, it shows its relation to ecological sciences [7, 21].
A universally accepted definition of TEK does not exist in the current literature . TEK can be defined in a variety of ways see [7–9, 19, 21]. Among them, Berkes’ (1999: 08) definition has been adopted: “… a cumulative body of knowledge, practices, and beliefs evolving through adaptative processes spread through generations by cultural transmission, about living beings’ (including humans) relations with one another and with their environments” . This definition has been chosen because of its three main characteristics (practical, dynamic, and local). According to Allut (2000), the practical character of TEK provides optimum conditions for the resolution of problems that concretely emerge from the natural environment and determine cognitive needs for action. The dynamic character allows one to live in and adapt to a world which is constantly changing, and local characteristics shape interpretations of natural and social surroundings —that is, its territory. These characteristics have allowed TEK to answer fundamental questions about natural resources and ecosystems by complementing, supplementing or even guiding natural sciences in the management of today’s natural resources .
The need to adapt to a changing world is the base of and fundamental to the construction of traditional calendars. According to Giddens (1991) and Le Goff (2003), the development of traditional calendars occurs through the observation of natural cycles (movements of the sun and moon, seasonal cycles, alternation of day and night). As such, it is possible to adopt Gardet’s (1975) perspective of time as knowledge [24, 28, 29].
In the modern world, time and the calendar have been measured by astronomic observations, however a change occurred in both individual and social focus; from a basis of movements occurring in nature to those of artificial movements, or in other words, from natural cycles to the clock [24, 29, 39]. Time is thus abstracted as a result of the scientific modalities to measure reality . Therefore, Gardet’s (1975) perspective of time as knowledge is valid for modern science as well .
According to Ken Lertzman (2009), there are many broad parallels between traditional resource management systems (TM) and modern science-based resource management (SM) systems. Therefore, it is possible to adopt the same concept for both systems. From this perspective, management systems can be understood as the processes through which the actions, goals and objectives “are legitimized by social norms, values, and institutions, [as are] the actors involved in carrying them out” (: 342). Consequently, the same author concludes that a management system is “the regulation of human behavior in relation to the environment, rather than direct manipulation of the environment per se”. As such, we adopt the Lertzman’s concept and in this article will analyze the regulation of the knowledge that supports human relations with the environment . In this sense, we are on the management of knowledge level in line with Lertzman’s approach.
The calendar is an instrument of system management. Since the Classical age, the calendar emerges as a way to tame natural time and to control human economic and social activities [28, 29]. Therefore, from the “time as knowledge perspective”, when the calendar is used to control natural resources, it is also used to control knowledge regarding time.
Based on the discussion above, we argue that the adoption of the perspective of “time as knowledge” , the concept of traditional ecological knowledge (TEK) , and the management of knowledge are adequate approaches to meet the objectives of this article. These concepts and approaches allow for the creation of cognitive categories to describe and analyze the pink shrimp fishing calendar constructed by artisanal fishers (cognitive needs) to adapt (dynamic) to the biophysical processes of their territories (local) in the Patos Lagoon estuary. With “time/calendar” as an underlying analytical category and the incorporation of traditional time in the construction of a resource management scenario in the Patos Lagoon estuary, it is possible to diagnose the (in)compatibilities between scientific resource management (SM) recommended by SK and traditional resource management (TM) grounded in TEK.