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Revista mexicana de biodiversidad - Factores ambientales asociados a los patrones en las comunidades de peces en un río de alta pendiente en la vertiente del golfo de México

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Revista mexicana de biodiversidad

versión impresa ISSN 1870-3453

Rev. Mex. Biodiv. vol.83 no.1 México mar. 2012

 

Ecología

 

Environmental factors associated with fish assemblage patterns in a high gradient river of the Gulf of Mexico slope

 

Factores ambientales asociados a los patrones en las comunidades de peces en un río de alta pendiente en la vertiente del golfo de México

 

Norman Mercado–Silva1*, John Lyons2, Edmundo Díaz–Pardo3, Saúl Navarrete3, Altagracia Gutiérrez–Hernández3

 

1 School of Natural Resources and the Environment, University of Arizona; 325 Biosciences East, Tucson, AZ 85721, USA. *nmercado@u.arizona.edu

2 University of Wisconsin Zoological Museum and Wisconsin Department of Natural Resources, 2801 Progress Road, Madison WI 53716.

3 Facultad de Ciencias Naturales, Universidad Autónoma de Querétaro. Avenida de las Ciencias S/N. Col. Juriquilla, 76230 Querétaro, Querétaro, Mexico.

 

Recibido: 10 junio 2010;
aceptado: 09 agosto 2011

 

Abstract

Using multivariate analyses of fish community and environmental data, we explored associations among 13 fish species and 9 ecological guilds and identified ecological gradients that explain patterns in the fish community of the La Antigua River (Veracruz, Mexico). Altitude, distance to ocean, stream width, and water temperature were the most important variables explaining community composition. Sites with high altitudes (> 1 393 m), cold water (< 17°C), located far from the ocean (> 100 km) and less than 5 m wide were dominated by non–native Onchorhynchus mykiss. Many sites exclusively inhabited by native poeciliids were also narrow (< 2 m), but were located at intermediate altitudes (1 039–1 400 m) and distances to the ocean (> 80 km, < 100 km) and had warmer water temperatures (> 20°C). Because 7 guilds were exclusive to a single species, results from the guild analysis were very similar to species–specific analyses. Higher species and guild diversity were found in wider sites (> 5 m), sites with lower altitudes (< 600 m), and sites closer to the ocean (< 71 km). Variables related to human influence did not explain trends found in the fish communities.

Key words: Veracruz, fish community, Mexican rivers, La Antigua River, ecological gradients.

 

Resumen

Utilizamos datos de la comunidad de peces y de variables ambientales y análisis multivariados para explorar asociaciones entre 13 especies y 9 gremios ecológicos en el río La Antigua (Veracruz, México). Además, identificamos gradientes ecológicos que explicaron los patrones en las comunidades de peces. Las variables más importantes en la determinación de la composición de la comunidad fueron altitud, distancia al océano, ancho de río y temperatura del agua. Los sitios ubicados a gran altitud (> 1 393 m), con aguas frías (< 17°C), lejos del océano (> 100 km) y menos de 5 m de ancho estuvieron dominados por la especie no nativa Onchorhynchus mykiss. Muchos sitios habitados exclusivamente por poecílidos nativos también fueron angostos (< 2 m), pero se ubicaron a altitudes intermedias (1 039–1 400 m), tuvieron temperaturas más cálidas (> 20°C) y estuvieron a distancias intermedias al océano (> 80 km, < 100 km). Siete de los gremios ecológicos fueron exclusivos de una especie por lo que los resultados del análisis de gremios fueron similares a los análisis de las especies taxonómicas. La diversidad específica y de gremios fue mayor en sitios más anchos (> 5 m), con menor altitud (< 600 m) y más cercanos al océano (< 71 km). Las variables relacionadas con la influencia antropogénica no tuvieron relevancia en la explicación de las tendencias encontradas.

Palabras clave: Veracruz, comunidad de peces, ríos mexicanos, río La Antigua, gradientes ecológicos.

 

Introduction

Multiple geological, historical and ecological factors determine the composition and structure of riparian fish communities. These factors operate at a variety of spatial and temporal scales. Several models have proposed a hierarchy of factors that can help explain trends in the assemblage of fish communities (Angermeier and Karr, 1983; Lamoroux et al., 2002; Hoeinghaus et al., 2007; Ibanez et al., 2007). Atop these hierarchies, long–duration evolutionary and zoogeographical processes (i.e., volcanic events, stream capture) determine the species that can potentially be present in ecosystems within a region. At lower hierarchies, smaller scale factors (i.e., water temperature, channel depth, biological interactions) determine which species are actually capable of occupying a particular area of a river (Angermeier and Winston, 1998; Matthews and Robison, 1998; Lyons and Mercado–Silva, 1999; D'Ambrosio et al., 2009).

A number of fish community patterns in lotic systems are well studied in temperate areas. For example, an increase in species richness in an upstream–downstream gradient as a result of increased habitat size, diversity, or both, is a general attribute for most river systems (other general trends reviewed in Matthews, 1998). A growing body of literature has tested these patterns in tropical systems around the world (Cop Ferreira and Petrere, 2009; Ibañez et al., 2009) often finding support for general trends. Most of these studies have focused on taxonomic richness as the variable to test against biotic and abiotic determining factors. Fewer studies have tested the influence of these factors in structuring the functional assemblage of fish communities (e.g., Schlosser 1982, Higgins 2009, Higgins and Strauss 2008).

The information that can be obtained from carrying out community comparisons between areas based on taxonomic identities is valuable, but can be much improved by analyzing functional attributes of the recorded organisms (Welcomme et al., 2006; Elliot et al., 2007). Integration of species into guilds has been used to increase the information on functioning, hierarchical structure and connectivity, and to simplify complex ecosystem analysis (Elliot et al., 2007). Guilds are defined as a group of species that exploit the same class of environmental resources in a similar way (Root, 1967).

Multivariate analyses have been broadly used to estimate the relative importance of ecological and geographic variables that explain the composition and structure of fish communities in freshwater ecosystems. The use of these methods in Mexican tropical systems is incipient. At the national level, only a few studies have attempted to determine the relative importance of multiple habitat, ecological or geographic variables in structuring fish communities (Díaz–Pardo et al., 1993; Paulo–Maya and Ramírez–Enciso, 1997; Lyons and Mercado–Silva, 1999; Ruíz–Gómez et al., 2008). These studies are lacking in Mexican rivers draining into the Gulf of Mexico, systems that carry a rich and complex freshwater fish fauna in very diverse freshwater environments.

Species descriptions, their distribution, and their parasites have mostly been the focus of freshwater ichthyological studies in the State of Veracruz, Mexico, and the Gulf of Mexico coast in general (Obregón–Barbosa et al., 1994; Garrido–Olvera et al., 2006; McEachran and Dewitt, 2008; Mercado–Silva et al., 2011). Little is known about how various ecological parameters may be affecting the composition and structure of fish communities in this region. This information is of utmost importance not only for our understanding of the basic biology and ecology of species, but also for understanding how fish communities are affected by a wide array of anthropogenic factors present in this area of the country, and to better inform fish and freshwater ecosystem conservation and protection measures.

The objective of this study was to explore not only associations among species and ecological guilds, but also to identify ecological gradients that could explain patterns in the fish community in a river draining into the Gulf of Mexico. We used multivariate analyses of community and environmental data and other statistical analyses to test our specific expectations of higher taxonomic and functional group richness in an upstream–downstream gradient, and a relatively restricted distribution of specialized functional groups to upper areas of the basin.

 

Materials and methods

Study area. The La Antigua river is a high gradient piedmont river originating from the Cofre de Perote volcano and adjacent mountains (Sierra Madre Oriental) (altitude= 4 200 m) in the states of Puebla and Veracruz (Mexico) that runs approximately 100 km east into the Gulf of Mexico. The La Antigua River is the 6th largest system in the state of Veracruz and has a total basin area of 2 326 km2 (Fig. 1) and an annual water discharge of 2.8 million m3 (Tamayo, 1996; Miller et al., 2005). The La Antigua river watershed has been declared by the National Biodiversity Commission (Conabio) as one of high diversity and of great hydrological importance (Conabio, 2000). The river plays an important role supplying water to urban centers, agriculture, and supporting commercial and subsistence fisheries. Typical of rivers in hilly terrain, in La Antigua numerous headwater streams coalesce to form montane and piedmont canyons, before the river arrives at the coastal plain. The La Antigua runs through a variety of landscapes, ranging from relatively undisturbed fragments of alpine to deciduous tropical and riparian forests, to sugar cane plantations and urban areas. Cattle grazing, shade coffee and mango plantations are common in the area. Deforestation due to increased agriculture and animal husbandry practices is an ongoing problem in the region (Muñoz–Villers and López–Blanco, 2007; Martínez et al., 2009). Land use changes have resulted in reduced water quality in different areas of the basin (Martínez et al., 2009). The La Antigua region has 3 seasons: wet (Jun.–Oct.), cool dry (Nov.– Mar.) and warm dry (Mar. – May). Our sampling sites were located between 19°35' and 19°10' N, and 96°38' and 97°10' W at altitudes ranging approximately from 200 to 1 800 m (Fig. 1).

Data collection. Water and habitat quality, and fish community data were collected between February and September 2007 from 34 sites in the La Antigua river basin. Eleven sites were visited more than once, resulting in 56 total collections available for analysis. The 11 sites were visited during each season. The remaining 23 sites were visited during only 1 of the 3 seasons. Two of the 23 sites had no fish and were dropped from analyses. Specific collection information is located in the Appendix.

We used seines, DC backpack electroshockers, and dipnets, as required, to obtain representative samples of the fish community in all habitats at each sampling site. Sampling efforts were continued until we detected no changes in the number of species captured or their relative abundance. Collection effort (CPUE) was calculated as number of fish per minute of total sampling time across all collection methods. All fishes captured were identified and counted. Voucher specimens for some of the collections were deposited in the Colección de Peces of the Universidad Autónoma de Querétaro, in Querétaro, Mexico. Most of the fishes captured were released unharmed after processing.

Water, habitat and geographic information were obtained for each site via direct measurements in the field (indicated by ª) or by analysis of existing ArcGis layers (indicated by b) (obtained from topographic maps of scale 1:50 000) and satellite images (Google Earth ©) (indicated by c) for the following 16 variables: mean stream widtha, maximum deptha, water velocitya, habitat diversitya, substrate diversitya, cover for fishesa, amount of erosion in land surrounding each sitea, landuse typea, water clarityª, quality of riparian forest at the siteª, site altitudec, horizontal distance via stream channels to the Gulf of Mexicoc, basin area upstream from the sampling pointc, stream order (Strahler method)b, distance via stream channels to nearest upstream urban areac, and water temperatureª. Units and categorical values for each variable are included in Table 1. Most of these variables are known as determinants of fish community composition in streams and rivers in North and Central America (Winemiller and Leslie, 1990; Rahel and Hubert, 1991; Lyons and Mercado–Silva, 1999).

Criteria for the construction of ecological guilds. We categorized each species into ecological guilds based on their reproduction, size, diet, position in the water column, and migratory tendencies. All of these guild attributes have been reported as useful for understanding the functional attributes of a fish community (Welcomme et al., 2006). Information for each species was obtained from literature (Table 2). Based on their reproductive strategies, fishes were categorized as having simple, complex or viviparous reproductive strategies. Simple reproduction refers to an oviparous strategy without nest building or parental care; complex reproduction refers to an oviparous strategy with either nest building or parental care. Fishes with a typical maximum adult total length (ATL) < 100 mm were categorized as small, fishes with ATL between 100 mm and 200 mm were categorized as medium, and fishes with ATL > 200 mm were categorized as large. Diet categories were herbivore (> 75% of diet dominated by plant materials), omnivore (with ≥ 25% animal material and ≥ 25% plant material or detritus) and carnivore (> 75% of diet dominated by animals). Fishes that are normally in constant contact with substrates were categorized as benthic, whereas those that occupy positions between the stream bottom and the water surface were categorized as water column fishes. Fishes that require migrations to brackish/salt water environments to complete their life cycles were categorized as migratory, while those that can complete their life cycles within their immediate habitat were categorized as local. We further identified species native and exotic to the Antigua basin, but did not include this information as part of our analyses.

Analysis. We built separate databases that contained geographic variables, habitat variables, and fish collection information. Separate fish collection databases were built using CPUE for species and CPUE for ecological guilds found at a site. We carried out preliminary analyses of species richness and species' relative abundances among samples from each site taken in different seasons; no relevant differences at any of the sites for either richness or relative abundance were related to season. Thus, for those sites sampled more than once, we retained only the sample from May 2007 (the year when most of the other collections were made) resulting in a total of 31 samples, 1 from each of the 31 sites, in the final dataset used for analyses.

We used Non Metric Multidimensional Scaling (NMDS), implemented through PC–ORD software (Version 5.18; McCune and Mefford 2006), to ordinate sites based on the 13 species, and separately on the 9 guilds, and then correlated site scores for NMDS results with values for the environmental variables, in order to identify ecological gradients. Our use of NMDS follows from the inclusion of non–linear and categorical data in our analysis; NMDS is an appropriate ordination technique for community analyses (Kenkel, 2006). For each ordination, we calculated 2 ordination axes, and the statistical significance of similarity in species' distributions among sites on each axis and for the overall ordination was determined by a Monte Carlo re–sampling procedure. For each ordination, bi–plots (sites and either species or guilds) were generated showing their relationships in multivariate space.

In the plots, samples that fell close to each other had similar species or guild composition, whereas those far apart had different fish assemblages. Similarly, species or guilds that were close in the plot had similar distribution patterns among sites, whereas those far apart had different distribution patterns. We used the results from the NMDS to interpret possible relationships among the sites and either species or guilds to our geographical and habitat variables for the following characteristics: altitude, temperature, stream width at site, basin area at site, and distance to the ocean. These relationships were studied using correlation analysis (Kendall's τ). Environmental variables were then added to the bi–plot (based on correlations with sample scores) to reveal these additional relationships within the context of the original bi–plot.

 

Results

We collected 5 412 individuals of 13 species in 8 families (Table 2). Two exotic species, Onchorhynchus mykiss and Xiphophorus helleri, were captured. Among all species collected, Heterandria bimaculata, Poecilia sphenops and Xiphophorus helleri (Table 3) were most numerous and widespread. We found 9 ecological guilds (Table 2). Seven guilds each comprised a unique species. Guilds VSOPL and VSCPL were the most abundant and widely distributed (Table 3).

Sites located at higher altitudes had lower water temperatures (r= –0.831, p < 0.001), smaller stream width (r= –0.392, p= 0.029), smaller basin area (r= –0.367, p= 0.042) and a larger distance to the ocean (r= 0.908, p > 0.001). Sites farther from the ocean also had lower water temperature (r= –0.768, p > 0.001), smaller stream width (r= –0.411, p= 0.024), and smaller basin area (r= –0.393, p < 0.029). Sites with greater basin area had higher water temperature (r= 0.411, p= 0.024).

Both of the NMDS ordinations and axes accounted for significantly more of the patterns in similarity among species distributions among sites than would be expected by chance. For the fish species ordination, the first 2 axes accounted for 62% of the similarity in fish distribution and abundance among sites, with each of the axis explaining 31%. For the first axis, H. bimaculata, Xiphophorus helleri and A. monticola had negative loadings and the remaining 11 species had positive loadings, which were relatively strong for 8 species (Table 3). Thus, sites with low scores on this axis were most likely to have relatively high abundance of either H. bimaculata or A. monticola and low abundance of most of the remaining species, whereas the opposite was true for sites with high scores. For the second axis, 11 species had negative loadings, with the largest magnitude for A. monticola, whereas H. bimaculata and X. helleri had relatively small magnitude and positive loadings. Sites with low scores on the second axis had relatively high numbers of many species, whereas sites with high scores would tend to have mainly H. bimaculata and X. helleri. For the fish guild ordination, the first 2 axis explained 86% of the variation in guild distribution and abundance among sites, with the first axis explaining 63% and the second 23%. For the first axis, 3 guilds had positive loadings, with VSCPL (i) having the greatest magnitude. The remaining 8 guilds in the first axis had negative scores, with SLCPL (d) having the greatest magnitude (Table 3). For the second axis, only 1 guild, SLCPL, had a positive loading, and the rest were negative, with the greatest magnitude for SLPOM (f) and CLOPL (a). For both axes in the guild ordination, sites with lower scores were more likely to comprise fish of several guilds, whereas sites with higher scores had fewer guilds present.

Patterns in the distribution of species and guilds were evident from the ordination plots. For the species ordination, sites dominated by H. bimaculata were distinctive from other sites and tended to have low scores on axis 1 and high scores on axis 2 (Fig. 2a). All other sites, including those dominated by O. mykiss, were not distinctive from one another, and clustered together with sites that had higher species richness. No sites had high scores on both axis 1 and axis 2. For the guild analysis, sites dominated by guild SLCPL (d, uniquely O. mykiss) were distinctive, with high scores on axis 2 and low scores on axis 1 (Fig. 2b). Sites dominated by guild VSCPL (i, uniquely H. bimaculata) had high scores on both axis 1 and axis 2. Other sites contained several different guilds, had low to intermediate scores on axis 1, and intermediate to high scores on axis 2.

Site scores from the 2 ordinations were significantly related to environmental variables. For the species ordination, the first axis was negatively correlated with distance from urban centers (Kendall's tau [τ]= –0.268) and positively correlated with stream order (τ= 0.180) and basin area (τ= 0.172). In other words, sites with higher (magnitude) scores on this axis tended to be of higher stream order and greater basin area (i.e., larger streams) and were located relatively close to population centers, whereas the opposite was true of sites with lower scores. The second axis was negatively correlated with stream order (τ= –0.408) and basin area (τ= –0.353), and positively correlated with distance to the ocean (τ= 0.233). Sites with higher scores on this axis were relatively smaller and located relatively farther from the ocean. For the guild ordination, the first axis was significantly negatively correlated with stream order (τ= –0.372) and basin area (τ= –0.177). Sites with higher scores on this axis tended to occur in smaller streams. The second axis had strong positive correlations with altitude (τ= 0.646) and distance from the ocean (τ= 0.547) and negative correlations with basin area (τ= –0.366), stream order (τ= –0.342), and distance from population centers (τ= –0.268). Sites with higher scores on this axis were mainly found on relatively smaller streams located at higher altitudes and farther from the ocean, but relatively closer to population centers.

 

Discussion

Abiotic and biotic variables are important in structuring stream fish assemblages (Gilliam and Fraser 2001; Higgins and Wilde 2005). The physical structure of a stream channel, along with flow regimes and energy inputs produce a consistent pattern of structure along a stream (Vannote et al. 1980). This pattern has been widely used to explain the spatial and temporal structure of fish assemblages (Hoeinghaus et al. 2003; Higgins 2009, Ibañez et al., 2009) in many lotic systems around the globe. Stream size and geographic attributes are associated with differences in the species composition and guild structure of fish communities in the La Antigua river system. Longitudinal zonation in species diversity and composition is common in stream–fish assemblages (Oberdorff et al., 1993; Ostrand and Wilde, 2002). Stream order, related to altitudinal position and stream size, has been linked to changes in species diversity (Hawkes, 1975; Godinho et al., 2000). Especially in large scale studies such as this, abiotic (e.g., climatic, geographic) factors often appear as drivers of community composition and assemblage structure and become more important than biotic factors (Jackson et al., 2001). The sharp inclination of the terrain and high altitudinal gradient of the La Antigua system may be the most important factors determining which species can be found in different areas of the river. High river slopes are known to affect upstream fish movement, impeding the passage of many species from lower to higher portions of the river (Lyons and Navarro–Pérez, 1990; Lyons et al., 1998; Rodiles–Hernández et al., 1999). In addition, along its short course from the high altitude volcanoes to the coastal plateau the La Antigua river has numerous falls >10m in altitude that likely block fish movement.

Several environmental variables used in our analysis are correlated with altitude and distance from the ocean. Water temperature is lower in higher elevation montane areas influenced by snowmelt from nearby volcanoes. In the La Antigua river, such low temperatures (10–20°C) can only be tolerated by O. mykiss, an introduced species from aquaculture activities. As the river descends, increasing temperatures allow for higher species richness, including species accustomed to warmer waters (for example, the families Cichlidae and Pimelodidae), and those which carry out seasonal reproductive migrations (S. gymnogaster and A. monticola) between fresh and saline waters. Distance to the ocean thus has an important effect on the composition of the fish communities.

The native fish fauna in the La Antigua basin is neotropical and includes most elements of the Papaloapan–Usumacinta division of Miller et al. (2005). We only found 2 non–native species in the area we sampled, O. mykiss (rainbow trout) and X. helleri. Numerous trout farming operations exist in the higher elevation areas of the La Antigua basin and adjacent basins, and trout are widely used in the restaurant industry of the region. Trout are commonly raised in artificial tanks that extract water from the numerous rivers in the basin. During the rainy season, it is common that the water–holding capacity of the tanks is surpassed and trout escape to the main stream. It is unknown if trout have established self–sustained, naturalized populations in the river. Xiphophorus helleri have most likely been introduced to the La Antigua river basin as escapees from the aquarium industry which is prevalent in the region. However, the status of X. helleri as a non–native species in high elevation areas of the basin is uncertain because native populations may exist in lower portions of the La Antigua basin (Rosen, 1960). Our collections failed to produce other non–native fishes that are known from several coastal systems in Veracruz: Oreochromis spp., Carassius auratus and Cyprinus carpio. It is likely that these species utilize low–flow, turbid–water habitats located lower areas in the basin than those we sampled.

Only 1 of the species we captured, Rhamdia guatemalensis, is listed as a species with special protection by the Mexican federal government (NOM–059–SEMARNAT–2001). However, it is important to note that the fish fauna in the La Antigua river is facing several conservation issues. A few samples, particularly those near sugar processing plants, in areas with intensive agriculture, and near urban centers, produced no fish. In some of these collection efforts low water quality (i.e., high turbidity, presence of detergents and other contaminants, or excess nutrients) was evident. An active commercial and subsistence fishery is present in the lower portions of the La Antigua basin. It is unknown if fishing activities are having adverse effects on fish populations in these areas.

Aside from variables like stream width, altitude, water temperature, distance to the ocean, and basin area, other variables did not help to explain the variability found in our fish collections. This may stem from the strong correlations that exist among the most explanatory variables on these 2 axes, which may obscure the effects of any other non–correlated variables. Alternatively, variables measured in our samples may not reflect the diverse habitat conditions that can be found throughout the basin. We expected that some variables related to habitat quality (i.e., cover for fish, bank erosion, quality of riparian vegetation) would help determine some of the trends we found in the communities. The absence of these may reflect some or all of several factors, such as insufficient sampling across the entire continuum of habitat quality existing in the basin, little effect of habitat quality on the viability of fish communities, or as stated above, the strong influence that geographic variables have in structuring the communities of the La Antigua river. Similarly, we may have insufficiently sampled higher order systems in the basin. Increased geographical coverage of sampling efforts could help in providing a better description of environmental factors that determine fish assemblage in the basin.

Similar to other studies in Mexican systems (Lyons and Mercado–Silva, 1999), the relatively high number of ecological guilds found in the fish community of the La Antigua river reflects that ecological differences follow taxonomical differences in these fish assemblages. This result may be a product of the criteria chosen for the definition of the guilds. These criteria were chosen since they may reflect the diversity of habitats that species can use within an ecosystem and may allow our understanding of a species' function in the community. Other criteria, based on other aspects of the life history of the species (Winemiller, 2005), could group more species into fewer guilds, which could change some of the interpretation of our results. The use of these criteria however could be hampered by the lack of information on the basic biology of many of the species in the La Antigua basin. Guild–based analyses of fish communities will benefit from further study of species life histories, especially those that can help in determining whether a species does or does not change its ecological function in the community as a result of ontogeny or opportunity (Jackson et al., 2001). We encourage future studies to consider other guilds that might be more responsive to the same or different environmental variables. Additionally, we suggest that future studies attempt to represent an entire study region or basin in a more balanced way in their sampling efforts. In our results, some overlap among ecological guilds may result simply from an unbalanced distribution of sampling sites.

It is important to note that other native species are known from the La Antigua basin and were not captured in our efforts. Especially in areas located near the Gulf of Mexico at lower altitudes, Eleotrids, Ictalurids, other species of Cichlids, and Gobiids are present. In locations near some of our sampling sites, Parachromis friedrichstalli (Cichlidae), Poecilia latipinna, and Poeciliopsis catemaconis (Poeciliidae) have also been collected (EDP – unpublished data). The fish fauna of the lower La Antigua river, remains largely unstudied.

To our knowledge, this is one of the first community–level studies of the fish assemblages in Mexican rivers of the Gulf Coast, especially for the numerous rivers that originate from the Neovolcanic Axis in Central Mexico. In addition to providing information on the composition and ecological attributes of the fish communities in this region, we believe the information presented herein could be important for future investigations and management decisions as to the conservation of the fish fauna of the State of Veracruz.

 

Acknowledgements

We are thankful to Emanuel Mimila, Miguel Rubio, Lyssette Muñóz–Villers, Gabriela Vázquez, David Escandón, Enrique Meza, Guillermo Salgado, Rosario Landgrave, Javier Tolome, Ariadna Martínez, I. Chacón, A. Barrera and two anonymous reviewers for their assistance with field work, technical support, and in the preparation of this manuscript. A portion of the work for this project was part of NMS postdoctoral research at the Instituto de Ecología, A.C. Funding for this research was provided by CONACYT project No. 43082 and FOMIX project No. 32679.

 

Literature cited

Angermeier, P. L. and J. R. Karr. 1983. Fish communities along environmental gradients in a system of tropical streams. Environmental Biology of Fishes 9:117–138.         [ Links ]

Angermeier, P. L. and M. R. Winston. 1998. Local versus regional influence on local diversity in stream communities in Virginia. Ecology 79:911–927.         [ Links ]

Conabio. 2000. Regiones hidrológicas prioritarias para la conservación de la biodiversidad. Consejo Nacional para la Conservación de la Biodiversidad, México D.F., México.         [ Links ]

Cop Ferreira, F. and M. Petrere Jr. 2009. The fish zonation of the Itanhaém river basin in the Atlantic forest of southeast Brazil. Hydrobiologia 636:11–34.         [ Links ]

D'Ambrosio, J. L., L. R. Williams, J. D. Witter and A. Ward. 2009. Effects of geomorphology, habitat, and spatial location on fish assemblages in a watershed in Ohio, USA. Environmental Monitoring and Assessment 148:325–341.         [ Links ]

Dawes, J. A. 1991. Livebearing fishes. A guide to their aquarium care, biology and classification. Blandforn. London. 240 p.         [ Links ]

Díaz–Pardo, E., M. A. Godínez–Rodríguez, E. López –López and E. Soto–Galera. 1993. Ecología de los peces de la cuenca del río Lerma, México. Anales de la Escuela Nacional de Ciencias Biológicas 39:103–127.         [ Links ]

Elliott, M., A. K. Whitfield, I. C. Potter, S. J. M. Blaber, D. P. Cyrus, F. G. Nordlie and T. D. Harrison. 2007. The guild approach to categorizing estuarine fish assemblages: a global review. Fish and Fisheries 8:241–268.         [ Links ]

Garrido–Olvera, L., L. García–Prieto and G. Pérez–Ponce de León. 2006. Checklist of the adult nematode parasites of fishes in freshwater localities from Mexico. Zootaxa 1202:1–45.         [ Links ]

Gilliam, J. F. and D. F. Fraser. 2001. Movement in corridors: Enhancement by predation threat, disturbance, and habitat structure. Ecology 82:258–273.         [ Links ]

Godinho, F. M., M. T. Ferreira and J. M. Santos. 2000. Variation in fish community composition along an Iberian river basin from low to high discharge: relative contributions of environmental and temporal variables. Ecology of Freshwater Fish 9:22–29.         [ Links ]

Hawkes, H. A. 1975. River zonation and classification. In River Ecology, B. R. Whitton, (ed.). Berkeley, University of California Press. p. 312–374.         [ Links ]

Higgins, C. L. 2009. Spatiotemporal variation in functional and taxonomic organization of stream–fish assemblages in central Texas. Aquatic Ecology 43:1133–1141.         [ Links ]

Higgins, C. L. and R. E. Strauss. 2008. Modeling stream–fish assemblages with niche apportionments models: patterns, processes and scale dependence. Transactions of the American Fisheries Society 137:696–706.         [ Links ]

Higgins, C. L. and G. R. Wilde. 2005. The role of salinity in structuring fish assemblages in a praire stream system. Hydrobiologia 549:197–203.         [ Links ]

Hoeinghaus, D. J., C. A. Layman, D. A. Arrington and K. O. Winemiller. 2003. Spatiotemporal variation in fish assemblage structure in tropical floodplain creeks. Environmental Biology of Fishes 67:379–387.         [ Links ]

Hoeinghaus, D. J., K. O. Winemiller and J. S. Birnbaum. 2007. Local and regional determinants of stream fish assemblage structure: inferences based on taxonomic vs. functional groups. Journal of Biogeography 34:324–338.         [ Links ]

Hulsey, C. D. 2006. Function of a key morphological innovation: fusion of the cichlid pharyngeal jaw. Proceedings of the Royal Society B 273:669–675.         [ Links ]

Ibanez, C., T. Oberdorff, G. Teugeis, V. Mamononekene, S. Lavoue, Y. Fermon, D. Paugy and P. K. Tohams. 2007. Fish assemblages structure and function along environmental gradients in rivers of Gabon (Africa). Ecology of Freshwater Fish 16:315–334.         [ Links ]

Ibañez, C., J. Belliard, R. M. Hughes, P. Irz, A. Kamdem–Toham, N. Lamoroux, P. A. Tedesco and T. Oberdorff. 2009. Convergence of temperate and tropical fish assemblages. Ecography 32:685–670.         [ Links ]

Jackson, D. A., P. R. Peres–Neto and J. D. Olden. 2001. What controls who is where in freshwater fish communities – the roles of biotic, abiotic, and spatial factors. Canadian Journal of Fisheries and Aquatic Sciences 58:157–170.         [ Links ]

Kenkel, N. C. 2006. On selecting an appropriate multivariate analysis. Canadian Journal of Plant Science 86:663–676.         [ Links ]

Lamoroux, N., N. L. Poff and P. L. Angermeier. 2002. Intercontinental convergence of stream fish community traits along geomorphic and hydraulic gradients. Ecology 83:1792–1807.         [ Links ]

Lyons, J., G. González–Hernández, E. Soto–Galera and M. Guzmán–Arroyo. 1998. Decline of freshwater fishes and fisheries in selected drainages of west central Mexico. Fisheries 23:10–18.         [ Links ]

Lyons, J. and N. Mercado–Silva. 1999. Patrones taxonómicos y ecológicos entre comunidades de peces en ríos y arroyos en el oeste de Jalisco, México. Anales de la Escuela Nacional de Ciencias Biológicas (Zoología) 70:169–190.         [ Links ]

Lyons, J. and S. Navarro–Pérez. 1990. Fishes of the Sierra de Manantlán. The Southwestern Naturalist 35:32–46.         [ Links ]

Martínez, M. L., O. Pérez–Maqueo, G. Vázquez, G. Castillo–Campos, J. García–Franco, K. Mehltreter, M. Equihua and R. Landgrave. 2009. Effects of land use change on biodiversity and ecosystem services in tropical montane cloud forests of Mexico. Forest Ecology and Management DOI: 10.1016/j.foreco.2009.02.023.         [ Links ]

Matthews, W. J. 1998. Patterns in freshwater fish ecology. Norwell, Kluwer Academic Publishers. 784 p.         [ Links ]

Matthews, W. J. and H. W. Robison. 1998. Influence of drainage connectivity, drainage area and regional species richness on fishes in the interior highlands of Arkansas. American Midland Naturalist 139:1–19.         [ Links ]

McCune, B. and M. J. Mefford. 2006. PC–ORD. Multivariate analysis of ecological date. Version 5.18. MjM Software, Gleneden Beach, Oregon.         [ Links ]

McEachran, J. D. and T. J. Dewitt. 2008. A new livebearing fish, Heterandria tuxtlaensis, from Lake Catemaco, Veracruz, Mexico (Cyprinodontiformes: Poeciliidae) Zootaxa 1824:45–54.         [ Links ]

Mercado–Silva, N., E. Díaz–Pardo, A. Gutierrez–Hernandez and E. Soto–Galera. 2011. Peces Dulceacuícolas. In La biodiversidad en Veracruz: estudio de Estado, vol. II, G. C. Castillo–Campos, C. Landero–Sánchez, J. Lorea–Hernández, E. Morales–Mávil, M. Soto–Esparza and E. Olguín–Palacios (eds.). Conabio/Gobierno del Estado de Veracruz/Universidad Veracruzana/Instituto de Ecología, A.C. México, D.F. p. 495–504.         [ Links ]

Mercado–Silva, N., J. Lyons, G. Salgado–Maldonado and M. Medina–Nava. 2002. Validation of a fish–based index of biotic integrity for streams and rivers of central Mexico. Reviews in Fish Biology and Fisheries 12:179–191.         [ Links ]

Miller, R. R., W. L. Minckley and S. R. Norris. 2005. Freshwater fishes of Mexico. The University of Chicago Press. Chicago. 490 p.         [ Links ]

Muñoz–Villers, L. E. and J. López–Blanco. 2007. Land use/cover changes using Landsat TM/ETM images in a tropical and biodiverse mountainous area of central–eastern Mexico. International Journal of Remote Sensing 29:71–93.         [ Links ]

NOM–059–SEMARNAT–2001 (Norma Oficial Mexicana). Protección ambiental – Especies nativas de México de Flora y Fauna Silvestres – Categorías de Riesgo y especificaciones para su inclusión, exclusión o cambio – Lista de Especies en Riesgo. SEMARNAT (Secretaría de Medio Ambiente y Recursos Naturales).         [ Links ]

Oberdorff, T., E. Guilbert and J. C. Lucchetta. 1993. Patterns of fish species richness in the Seine River basin, France. Hydrobiologia 259:157–167.         [ Links ]

Obregón–Barbosa, H., S. Contreras–Balderas and M. d. L. Lozano–Vilano. 1994. The fishes of northern and central Veracruz, Mexico. Hydrobiologia 286:79–95.         [ Links ]

Ostrand, K. G. and G. R. Wilde. 2002. Seasonal and spatial variation in a praire stream–fish assemblage. Ecology of Freshwater Fish 11:137–149.         [ Links ]

Paulo–Maya, J. and A. Ramírez–Enciso. 1997. Distribución espacio–temporal de la ictiofauna del río Cutzamala, Michoacán, México. Revista Biología Tropical 45:845–853.         [ Links ]

Rahel, F. J. and W. A. Hubert. 1991. Fish assemblages and habitat gradients in a Rocky Mountain – Great Plains stream; biotic zonation and additive patterns of community change. Transactions of the American Fisheries Society 102:319–332.         [ Links ]

Rodiles–Hernández, R., E. Díaz–Pardo and J. Lyons. 1999. Patterns in the species diversity and composition of the fish community of the Lacanja River, Chiapas, Mexico. Journal of Freshwater Ecology 14:455–468.         [ Links ]

Root, R. B. 1967. The niche exploitation pattern of the blue–grey gnatcatcher. Ecological Monographs 37:317–350.         [ Links ]

Rosen, D. E. 1960. Middle–American Poeciilid fishes of the genus Xiphophorus. Bulletin of the Florida State Museum 5:1–242.         [ Links ]

Ruíz–Gómez, M. d. L., J. F. Méndez–Sánchez, F. d. J. Rodríguez–Romero and C. M. Taylor. 2008. Spatiotemporal changes in fish assemblages of Los Terreros Creek, an isolated stream system in headwaters of the Lerma River, Central Mexico. The Southwestern Naturalist 53:224–229.         [ Links ]

Schlosser, I. J. 1982. Fish community structure and function along two habitat gradients in a headwater stream. Ecological Monographs 52:395–414.         [ Links ]

Tamayo, J. L., 1996. Geografía Moderna de México, 10th ed., Trillas. México, D. F. 400 p.         [ Links ]

Trujillo–Jiménez, P. and H. Toledo–Beto. 2007. Alimentación de los peces dulceauícolas tropicales Heterandria bimaculata y Poecilia sphenops (Cyprinodontiformes: Poeciliidae). Revista de Biología Tropical 55:603–615.         [ Links ]

Tobler, M. 2008. Divergence in trophic ecology characterizes colonization of extreme habitats. Biological Journal of the Linnean Society 95:517–528.         [ Links ]

Vannote, R. L., G. W. Minshall, K. W. Cummins, J. R. Sedell and C. E. Cushing. 1980. The river continuum concept. Canadian Journal of Fisheries and Aquatic Sciences 37:130–137.         [ Links ]

Welcomme, R. L., K. O. Winemiller and I. G. Cowx. 2006. Fish environmental guilds as a tool for assessment of ecological condition of rivers. River Research and Applications 22:377–396.         [ Links ]

Winemiller, K. O. 2005. Life history strategies, population regulation, and implications for fisheries management. Canadian Journal of Fisheries and Aquatic Sciences 62:872–885.         [ Links ]

Winemiller, K. O. and M. A. Leslie. 1990. Fish assemblages across a complex, tropical freshwater/marine ecotone. Environmental Biology of Fishes 34:29–50.         [ Links ]