Manuel J Zetina-Rejón

National Polytechnic Institute | IPN · Laboratorio de Dinámica y Manejo de Ecosistemas Acuáticos

The trophic dynamics of islands with low terrestrial primary productivity often depend on marine allochthonous inputs from nearby donor habitats. For instance, on Malpelo Island, Colombia (4° 00′ 05.63″ N; 81° 36′ 36.41″ W), the Nazca booby Sula granti affects the productivity and trophic dynamics of the terrestrial ecosystem by delivering nutrient...

In the scientific literature it is possible to find a series of models for both stock and ecosystem evaluation that consider environmental changes. However, in Mexico, the conventional management of exploited resources presents weaknesses by not duly considering these changes in the management proposals. Nowadays, marine ecosystems, in addition to...

Diferentes métricas de biodiversidad se deben explorar para evaluar de manera más eficiente los cambios observados en las comunidades. Sin embargo, el desempeño de distintas métricas de biodiversidad no ha sido explorado en el golfo de Batabanó, lo que puede dificultar la selección de índices adecuados para el monitoreo ambiental. Para solventar es...

Different biodiversity metrics should be explored to more effi ciently assess observed changes in communities. However, the performance of different biodiversity metrics has not been explored in the Gulf of Batabanó, to hampering diffi cult to select suitable indices for environmental monitoring. To solve this problem, six biodiversity metrics (spe...

Coastal habitats are essential for ecological processes and provide important ecosystem services. The Galapagos archipelago has a wide diversity of ichthyofauna which preservation guarantees the functioning of the marine ecosystem. In this study, we used ecological and taxonomic indices as well as multivariate analysis to identify spatiotemporal ch...

Changes in feeding habits during ontogeny show that organisms can present shifts in foraging behavior during their life cycle, which can alter local trophic dynamics. Therefore, describing diet across species ontogeny clarifies the ecological niche and ecosystem role of marine predators. In this study, diet tracers (stable isotope analysis) were an...

Trophic networks are the way by which energy is distributed through the ecosystem and out of it. Each ecosystem at a particular functional developmental state (FDS) has attributes that can be measured and understood through the food web. Trophic interactions can further our understanding of the FDS of coral reefs that can be associated with their g...

The southeastern Gulf of California is located where two major ocean systems meet: the California Current at the north and the North Equatorial current at the south, however the ecosystem-level effects that have such confluence remain unknown. In this study, we compared the structure and function of this ecosystem between two periods and . We based...

One of the great scientific challenges for the management of fish resources is to address the question of how much biomass must remain in the sea after fishing in order to maintain the functions of the ecosystem. We define this fishing limit as an ecosystem limit reference point, ELRP, that could be used for marine resource management. The basic co...

Ecosystem approaches to fisheries management (EAF) are increasingly relevant for intergovernmental fisheries policies, national management plans, and seafood certification guidelines. To aid in integration of EAF in tropical artisanal fisheries, this study evaluates the potential ecosystem impacts of four distinct fisheries (kelp forest, sandy shor...

The exploration of gradients of development stages of coral reef ecosystems is a subject poorly studied, especially when they exhibit multiple degrees of geomorphological or structural development or both. The objective of the present work was to study the gradient of functional and structural maturity of the Mexican Caribbean coral reefs (CM). Her...

Science today is facing a great challenge regarding the provision of scientific advice to the use and conservation of living marine resources, where natural systems are changing continuously in response to climate change. There is no precedent for the current situation; never before has mankind been faced with a scenario such as this, where most fi...

The shrimp trawl fishery in the southeastern Gulf of California is one of the most important in Mexico due to the high economic value of the resource in the national and international market. The management of this fishery is based on permits, a no-trawling zone, a no-fishing season and regulations of fishing gears. In order to analyze the efficien...

In this study, the trophic structure of the pelagic copepod community was analyzed in six geographical zones in the eastern tropical Pacific Ocean. Zooplankton samples were collected on two oceanographic cruises from August to December 2003 using a bongo cone net (333 μm mesh light). The isotopic signatures were measured as δ¹⁵N and δ¹³C in twelve...

The trophic structure of the fish community ecosystem in the Terminos Lagoon (southern Gulf of Mexico) has shown a range of functional changes. The description of the heterogeneity of functional traits in a biological community allows the identification of the relevant functions in an ecosystem. An analysis was conducted of the functional traits (t...

Accurate knowledge on fish trophic ecology and its modifications is crucial for understanding the impact of global change on ecosystems. In this context, we investigated the value of the δ¹³C and δ¹⁵N of otolith soluble organic matter (SOM) for identifying temporal diet shifts in American Silver Perch (Bairdiella chrysoura) over a 30-years period c...

Ecosystem-based fisheries management (EBFM) and ecosystem restoration are gaining momentum worldwide, including in the U.S. Gulf of Mexico (“GOM”). Ecosystem models are valuable tools for informing EBFM and restoration activities. In this paper, we provide guidance and a roadmap for ecosystem modeling in the GOM, with an emphasis on model developme...

In this contribution, we discuss the need for an ecosystems-type fisheries management approach, especially when the Campeche Bank subarea of the Gulf of Mexico Large Marine Ecosystem (LME) is strongly influenced by environmental changes. In these circumstances, the carrying capacity and the subarea structure and its organization do not reflect the...

The Gulf of California Large Marine Ecosystem (GoC-LME) is highly productive with a high diversity of marine species, including endemics and endangered, threatened or protected species thus, it is considered one of the ten marine biodiversity hotspots in the world. The significance of such areas typically conflicts with the exploitation of fish res...

Opisthonema libertate (Pacific thread herring) and Cetengraulis mysticetus (Pacific anchovy) are the two most important herring stocks exploited in the southeastern Gulf of California (SGC). The certification of these stocks is currently planned for achieving sustainable fisheries. This study analysed the role of these two species in the structure,...

Currently, one of the most relevant topics in ecology is the understanding of the relationship that exists between biological diversity and functional diversity on ecosystem processes. It has been pointed out that key processes in ecosystems depend more on functional diversity than on species diversity. In this research, functional diversity indica...

The trophic aspect of ecology has been studied for more than six decades; in this contribution we address theoretical aspects relative to the concept of trophic flow at the ecosystem level and from the thermodynamics point of view. Much of this knowledge is greatly based on the consideration that ecosystems are functional units that are worth globa...

Opisthonema libertate and Cetengraulis mysticetus are exploited resources in the southeastern Gulf of California. In addition to their socio-economic importance, these species have great ecological relevance in the ecosystem because they form part of the base of the food chain. The contribution of this analysis is about the role of these species in...

One of the issues that have drawn the attention of ecologists is how ecosystems that are both complex and stable are organized. It has been argued that ecosystems have regulatory mechanisms that optimize their structure and function. These mechanisms are known as self-organizing processes that are regulated by environmental forcing factors. In this...

Terminos Lagoon has a high diversity of species and habitats and is the largest coastal lagoon in the southern Gulf of Mexico. It has been a natural protected area since 1994, but in recent decades, environmental changes have modified its biological communities and habitats. In this study, we construct three trophic models for the periods 1980, 199...

Mexican legislation envisages the creation of public participation, nevertheless, there is no criterion to identify representative key players among involved sectors. We used a topological analysis with the objec- tive to identify these key players in the swimming crab Callinectes bellicosus fishery of Sonora. In 2013, a non-probabilistic sampling...

The highest rates of incidental catch of non-target species is associated with shrimp bottom trawl fisheries. This could lead to adverse effects on the structure and functioning of ecosystems. However, the structural and functional variability of fish communities captured as by-catch from this fishery in the Colombian Caribbean Sea have been poorly...

Ecosystems that change through time impose new scientific challenges for fisheries management advice. We present a case study to illustrate our view on how to face such challenges. The Pink Shrimp fishery in the Southern Gulf of Mexico has collapsed. Annual yields were about 24,000 metric tons during the mid-1950s to early 1970s; currently, they ar...

Latitudinal patterns of composition, biogeographic affinity and indicators of taxonomic diversity are described for the by-catch fish community in five typical shrimping areas in the Mexican Pacific (Upper Gulf of California, Sinaloa-Nayarit, Jalisco-Colima, Michoacán-Guerrero and Gulf of Tehuantepec). The taxonomic composition included two classes...

Marine ecosystems are subject to different disturbances such as trophic relationships, environmental changes, overfishing and social pressure, which may modify their structure and functioning over time; and therefore, these disturbances increase uncertainty about management strategies of fisheries resources. The objetive of this study is contribute...

Recently, stable-isotope analyses have been coupled with mixing models to determine trophic relationships by identifying the most important types of prey and assessing their relative contribution to the diet. This method has advantages over stomach-content analysis and is emerging as a powerful tool to determine trophic relationships. We analysed t...

Ecosystem approach for fisheries management has been promoted in recent time before the challenge of collapsing fisheries worldwide. The aim of this study is to accomplish a bioeconomic analysis of fisheries by maximizing net income and conserving ecosystem stability, in order to explore if there is a relationship between the ecosystem and bioecono...

The Eastern Tropical Pacific Ocean (ETPO) is a region of interest for commercial fisheries but is subject to high oceanographic variability, which affects primary and secondary production. Because pelagic copepods contribute significantly to secondary productivity, they were investigated to examine community structure variation both temporally and...

A nivel mundial, en especial en Latinoamérica, la pesca artesanal genera altos niveles de captura y es una de las principales actividades productivas de las zonas costeras tropicales. Sin embargo, la fuerte presión generada por esta actividad puede atentar contra la sustentabilidad de los recursos pesqueros limitando el normal desarrollo de los pro...

One of the main concerns of shrimp fisheries is the associ-ated impact on ecosystem biodiversity, particularly on fish assemblages that are poorly characterized yet likely very rele-vant to the health of the ecosystem. The continental shelf along the eastern coast of the mouth of the Gulf of Califor-nia is a region of high biodiversity that harbors...

From an ecosystem management perspective, analysis of the functional roles of species is a challenge. It is valuable to determine which species are irreplaceable within a given community based on their contribution to the system’s organization. This study relates the emergent functional and structural indices of biological groups estimated from a t...

A fish farm in Southeastern Spain was described using an Ecopath mass-balanced model, aimed at characterising its structure, the interactions among ecological groups and the impact of fish farms and fisheries. The model comprised 41 functional groups (including the artificial food input). Comparing consumption and respiration to total system throug...

a b s t r a c t Understanding of the intricate interactions of endemic species with anthropogenic impacts of diverse economic interests on ecosystems is of paramount importance to the implementation of effective con-servation programs. A trophic mass-balance model was used to analyze the structural properties of the North and Central Gulf of Califo...

INTRODUCTION The fish family Carangidae includes a relatively large number of commercially important species. These species are used primarily for human consumption. They are exploited in commercial fisheries using several gear types, such as trawls, purse nets, traps, and lines. The Peruvian moonfish, (known also as Pacific moonfish), Selene peru-...

The use of food resources in five of the most abundant fish species (Occidentarius platypogon,Cynoscion parvipinnis, Menticirrhus undulatus, Trachinotus paitensis and Heterodontus francisci) in San Ignacio Lagoon, Baja California Sur, Mexico is described. Prey composition, seasonal changes, diet breadth, trophic diversity and trophic overlap were a...

The present study was performed with the purpose of describing the length-weight relationships for 64 species from 36 fish families of ecological and commercial importance, found at the soft bottom of the continental shelf on the Eastern coast of the mouth of the Gulf of California. The knowing the LWR is important because it provides information o...

Fishing mortality and primary production (or proxy for) were used to drive the dynamics of fish assemblages in 9 trophodynamic models of contrasting marine ecosystems. Historical trends in abundance were reconstructed by fitting model predictions to observations from stock assessments and fisheries independent survey data. The model fitting exercis...

Large jellyfish blooms have occurred in the East China Sea (ECS) during the last decade, a period also characterized by increasing fishing pressure, eutrophication, and changing climatic conditions. As large jellyfish blooms may have detrimental effects on fishery resources and ecosystem functioning it is desirable to understand the factors leading...

The southern Gulf of Mexico has historically sustained important fish- eries, particularly shrimp. From the mid-1950s to early 1970s, annual yields of shrimp averaged about 27,000 metric tons (mt), of which the pink shrimp Farfantepenaeus du- orarum contributed more than 80%. At that time, three fleets, from the United States, Cuba, and Mexico, exp...

The pink shrimp was a very important fishery in the southern Gulf of Mexico, but it is cur-rently collapsed. In the early 1970s, fishery yields peaked at about 27,000 t per year, of which the pink shrimp was 90%. At present, yields are around 3000 t per year, and pink shrimp contributes less than 1000 t of this. Several studies indicate the main ca...

Alvarado is one of the most productive estuary-lagoon systems in the Mexican Gulf of Mexico. It has great economic and ecological importance due to high fisheries productivity and because it serves as a nursery, feeding, and reproduction area for numerous populations of fishes and crustaceans. Because of this, extensive studies have focused on biol...

Summary The inshore lizardfish, Synodus foetens, is one of the most common coastal demersal predators on the continental shelf of the Gulf of Mexico (GOM), but the biology and feeding ecology of this species is virtually unknown. Between November 2001 and January 2003 (10 collections), 603 individuals of S. foetens ranging from 112 to 420 mm standa...

We analyse the concept of carrying capacity (CC), from populations to the biosphere, and offer a definition suitable for any level. For communities and ecosystems, the CC evokes density-dependence assumptions analogous to those of population dynamics. At the biosphere level, human CC is uncertain and dynamic, leading to apprehensive rather than pra...

Huizache–Caimanero is a tropical brackishwater lagoon in western Mexico where there has been an important shrimp fishery for a long time. Four other, less important fish groups in this ecosystem are also exploited. We use a previously constructed Ecopath model to explore harvesting strategies for multispecies management. Changes in fishing mortalit...

The impact of some optimized harvesting strategies on ecosystem structure was investigated using a mass-balanced model of the ecosystem in the southwestern Gulf of Mexico, where there are four types of artisanal fisheries and a shrimp fishery that has collapsed. The Ecopath with Ecosim software was used to simulate harvesting strategies aimed at op...

The Huizache–Caimanero coastal lagoon complex on the Pacific coast of Mexico supports an important shrimp fishery and is one of the most productive systems in catch per unit area of this resource. Four other less important fish groups are also exploited. In this study, we integrated the available information of the system into a mass-balance trophi...

The Huizache-Caimanero coastal lagoon system supports an economically important artisanal shrimp fishery and a less valuable finfish fishery. We analyze the response of the fisheries and the ecosystem to changes in fishing effort. To do this we use Ecosim - a dynamic version of Ecopath, which is a steady-state model emphasizing natural rates of gro...