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School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

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Biogeography

Articles 1 - 5 of 5

Full-Text Articles in Physical Sciences and Mathematics

First Description Of Deep Benthic Habitats And Communities Of Oceanic Islands And Seamounts Of The Nazca Desventuradas Marine Park, Chile, Jan M. Tapia-Guerra, Ariadna Mecho, Erin E. Easton, María De Los Ángeles Gallardo, Matthias Gorny, Javier Sellanes Mar 2021

First Description Of Deep Benthic Habitats And Communities Of Oceanic Islands And Seamounts Of The Nazca Desventuradas Marine Park, Chile, Jan M. Tapia-Guerra, Ariadna Mecho, Erin E. Easton, María De Los Ángeles Gallardo, Matthias Gorny, Javier Sellanes

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Seamounts and oceanic islands of the Chilean Exclusive Economic Zone at the intersection of the Nazca and Salas y Gómez ridges lie within one of the least explored areas in the world. The sparse information available, mainly for seamounts outside Chilean jurisdiction and shallow-water fauna of the Desventuradas Islands, suggests that the area is a hotspot of endemism. This apparent uniqueness of the fauna motivated the creation of the large Nazca-Desventuradas Marine Park (NDMP, ~ 300,000 km2) around the small islands San Felix and San Ambrosio in 2015. We report for the first time a detailed description of benthic microhabitats …


Environmental Forcing On Zooplankton Distribution In The Coastal Waters Of The Galápagos Islands: Spatial And Seasonal Patterns In The Copepod Community Structure, Diego F. Figueroa Mar 2021

Environmental Forcing On Zooplankton Distribution In The Coastal Waters Of The Galápagos Islands: Spatial And Seasonal Patterns In The Copepod Community Structure, Diego F. Figueroa

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

The oceanographic setting of the Galápagos Archipelago results in a spatially diverse marine environment suitable for a variety of species with different climatic requirements. The goal of this study is to demonstrate that the community of zooplankton in the Galápagos is highly structured by regional differences in productivity patterns and advective sources. Results are mostly based on biodiversity patterns of the copepod community collected over the Galápagos shelf between 2004 and 2006. Two contrasting marine environments were observed: a nutrientrich upwelling system with a shallow mixed layer and a diatom-dominated phytoplankton community in the west, and a non-upwelling system with …


Architectonica Karsteni Rutsch, 1934 (Gastropoda: Architectonicidae) In Seamounts Of The Nazca-Desventuradas Marine Park: First Evidence Of An Extant Population In Chilean Waters Since The Miocene, Cynthia M. Asorey, Javier Sellanes, Erin E. Easton, Rüdiger Bieler, Ariadna Mecho Jan 2020

Architectonica Karsteni Rutsch, 1934 (Gastropoda: Architectonicidae) In Seamounts Of The Nazca-Desventuradas Marine Park: First Evidence Of An Extant Population In Chilean Waters Since The Miocene, Cynthia M. Asorey, Javier Sellanes, Erin E. Easton, Rüdiger Bieler, Ariadna Mecho

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

The presence of Architectonicidae in Chile was previously recorded only from fossil material of eight species present during the Lower Miocene, when Architectonica karsteni had a geographic range that extended from Costa Rica to central Chile (34°S). No evidence of the presence of the family in Chile after the Lower Miocene have been reported. As part of this study, we report the discovery of A. karsteni at four seamountsat ~200 m water depth in the recently created Nazca-Desventuradas Marine Park, located ~900 km west of continental Chile. Morphological identification was based on protoconch diameter, coloration patterns, and teleoconch sculpture. We …


Unexplored Diversity Of The Mesophotic Echinoderm Fauna Of The Easter Island Ecoregion, Ariadna Mecho, Erin E. Easton, Javier Sellanes, Matthias Gorny, Christopher Mah Jun 2019

Unexplored Diversity Of The Mesophotic Echinoderm Fauna Of The Easter Island Ecoregion, Ariadna Mecho, Erin E. Easton, Javier Sellanes, Matthias Gorny, Christopher Mah

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

The Easter Island ecoregion (EIE) is one of the most remote marine areas of the world and encompasses a vast and fragile ecosystem including oceanic islands and seamounts. In January 2014 and March 2016, a remotely operated vehicle was used to explore a subsurface peak off Easter Island (27.23°S, 109.48°W) and a seamount (26.92°S, 110.26°W), respectively located 10 km southwest and 98 km west of the island. More than 950 echinoderms were observed in the 5 h of video recorded during the seven dives conducted at depths between ~ 160 and 280 m. The communities of echinoderms observed at these …


Oceanographic Conditions And Diversity Of Sea Stars (Echinodermata: Asteroidea) In The Gulf Of California, México, Carlos E. Cintra-Buenrostro, Hector Reyes-Bonilla, Maria Dinorah Herrero-Perezrul Jan 2005

Oceanographic Conditions And Diversity Of Sea Stars (Echinodermata: Asteroidea) In The Gulf Of California, México, Carlos E. Cintra-Buenrostro, Hector Reyes-Bonilla, Maria Dinorah Herrero-Perezrul

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Species richness is one of the best indicators of biodiversity. However, there are few investigations on concordance of diversity patterns and environmental settings for marine regions. The objectives of this study were to correlate species richness of shallow water (< 200 m deep) sea stars with key oceanographic factors in the Gulf of California, México, and to predict species richness of Asteroidea using multiple regressions. In these analyses the Gulf was divided into nine sections of one degree in latitude (from 23 - 31° N), at each section we recorded: continental shelf area (at 100 and 200 m depth), temperature mean and range at three depth levels (0, 60 and 120 m), thermocline depth, surface nutrient concentrations (nitrates, phosphates and silicates), surface photosynthetic pigment concentration, and integrated productivity. Sea star species richness at each latitudinal section was estimated from literature data, new collections and museum records. Species were assigned to one of the following feeding guilds: predators of small mobile invertebrates (I), detritivores (D), predators of colonial organisms (C), generalist carnivores (G), and planktivores (P). There are 47 shallow water asteroid species in the Gulf of California (16 I, 15 D, eight C, six G, one P and one not assigned). Total species richness and guild species richness showed strong latitudinal attenuation patterns and were higher in the southernmost Gulf, an area characterized by a narrow shelf, high temperature, and low nutrient concentrations. Species diversity for each guild was correlated to a set of oceanographic parameters: temperature, nitrate concentration, and integrated productivity were linked to richness in must cases. We detected that nutrients and surface pigments always presented negative relationships with species richness, indicating that productive environments limit asteroid diversity in the study area. Finally, the postulated regression models to estimate species richness from oceanographic data were significant and highly precise. We conclude that species richness of Asteroidea in the Gulf of California is related to oceanographic conditions and can be estimated from regional oceanographic information.