Comparison of Deep-River and Adjacent Sandy-Beach Fish Assemblages in the Napo River Basin, Eastern Ecuador

Autor:	Myriam Ibarra, Ramiro Barriga-Salazar, Donald J. Stewart
Rok vydání:	2002
Předmět:	geography geography.geographical_feature_category Amazon rainforest Ecology Ecological distance Drainage basin Aquatic Science Habitat Indicator species Tributary Fish Animal Science and Zoology Species richness Ecology Evolution Behavior and Systematics
Zdroj:	Copeia. 2002:333-343
ISSN:	1938-5110 0045-8511
DOI:	10.1643/0045-8511(2002)002[0333:codraa]2.0.co;2
Popis:	We sampled fishes with a small trawl in the deep midchannel and with beach seines on nearby sandy beaches at five sites along two parallel headwater tributaries of the upper Amazon in Eastern Ecuador. We quantified ecological distance between fish assemblages of deep-river and beach habitats and compared assemblage composition, species richness, and diversity. Results of detrended correspondence analyses (DCA) and two-way indicator species analyses (TWINSPAN) clearly revealed the presence of a striking faunal change (i.e., about 92% dissimilarity) between beach-zone and off-shore fishes. The boundary between these assemblages occurred at about 2 m depth. Beach samples collected as far apart as 325 km were more similar to each other than to trawl samples taken only 10s of meters away. The beach-zone fish assemblage was strongly dominated by small characins, whereas the deep-river habitat was dominated by catfishes and weakly electric gymnotiforms. Apparent adaptations to deep-water habitats includ...
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::1952b96257d47f390d657ec60f95350c https://doi.org/10.1643/0045-8511(2002)002[0333:codraa]2.0.co Zobrazit plný text záznamu