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2018
Mullineaux, LS, Metaxas A, Beaulieu SE, Bright M, Gollner S, Grupe BM, Herrera S, Kellner JB, Levin LA, Mitarai S, Neubert MG, Thurnherr AM, Tunnicliffe V, Watanabe HK, Won YJ.  2018.  Exploring the ecology of deep-sea hydrothermal vents in a metacommunity framework. Frontiers in Marine Science. 5   10.3389/fmars.2018.00049   AbstractWebsite

Species inhabiting deep-sea hydrothermal vents are strongly influenced by the geological setting, as it provides the chemical-rich fluids supporting the food web, creates the patchwork of seafloor habitat, and generates catastrophic disturbances that can eradicate entire communities. The patches of vent habitat host a network of communities (a metacommunity) connected by dispersal of planktonic larvae. The dynamics of the metacommunity are influenced not only by birth rates, death rates and interactions of populations at the local site, but also by regional influences on dispersal from different sites. The connections to other communities provide a mechanism for dynamics at a local site to affect features of the regional biota. In this paper, we explore the challenges and potential benefits of applying metacommunity theory to vent communities, with a particular focus on effects of disturbance. We synthesize field observations to inform models and identify data gaps that need to be addressed to answer key questions including: (1) what is the influence of the magnitude and rate of disturbance on ecological attributes, such as time to extinction or resilience in ametacommunity; (2) what interactions between local and regional processes control species diversity, and (3) which communities are "hot spots" of key ecological significance. We conclude by assessing our ability to evaluate resilience of vent metacommunities to human disturbance (e.g., deep-sea mining). Although the resilience of a few highly disturbed vent systems in the eastern Pacific has been quantified, these values cannot be generalized to remote locales in the western Pacific ormid Atlantic where disturbance rates are different and information on local controls is missing.

2000
Rathburn, AE, Levin LA, Held Z, Lohmann KC.  2000.  Benthic foraminifera associated with cold methane seeps on the northern California margin: Ecology and stable isotopic composition. Marine Micropaleontology. 38:247-266.   10.1016/s0377-8398(00)00005-0   AbstractWebsite

Release of methane from large marine reservoirs has been linked to climate change, as a causal mechanism and a consequence of temperature changes, during the Quaternary and the Paleocene. These inferred linkages are based primarily on variations in benthic foraminiferal stable isotope signatures. Few modem analog data exist, however, to assess the influence of methane flux on the geochemistry or faunal characteristics of benthic foraminiferal assemblages. Here we present analyses of the ecology and stable isotopic compositions of living (Rose Bengal stained) and dead (fossil) foraminifera (>150 mu m) from cold methane seeps on the slope off of the Eel River, northern California (500-525 m), and discuss potential applications for reconstructions of methane release in the past and present. Calcareous foraminiferal assemblages associated with Calyptogena clam bed seeps were comprised of species that are also found in organic-rich environments. Cosmopolitan, paleoceanographically important taxa were abundant; these included Uvigerina, Bolivina, Chilostomella, Globobulimina, and Nonionella. We speculate that seep foraminifera are attracted to the availability of food at cold seeps, and require no adaptations beyond those needed for life in organic-rich, reducing environments. Oxygen isotopic values of the tests of living foraminiferal assemblages from seeps had a high range (up to 0.69 parts per thousand) as did carbon isotopic values (up to 1.02 parts per thousand). Many living foraminiferal isotope values were within the range exhibited by the same or similar species in non-seep environments. Carbon isotopic values of fossil foraminifera found deeper in the sediments (18-20 cm), however, were 4.10 parts per thousand (U. peregrina) and 3.60 parts per thousand (B. subargentea) more negative than living delta(13)C values. These results suggest that delta(13)C values of foraminiferal tests reflect methane seepage and species-specific differences in isotopic composition, and can indicate temporal variations in seep activity. A better understanding of foraminiferal ecology and stable isotopic composition will enhance paleo-seep recognition, and improve interpretations of climatic and paleoceanographic change. (C) 2000 Elsevier Science B.V. All rights reserved.

1992
Gooday, AJ, Levin LA, Thomas CL, Hecker B.  1992.  The distribution and ecology of Bathysiphon filiformis sars and B. major de folin (Protista, Foraminiferida) on the continental slope off North Carolina. Journal of Foraminiferal Research. 22:129-146. AbstractWebsite

Two large species of the agglutinated foraminifera genus Bathysiphon are common in samples and photographs from bathyal depths on the North Carolina continental slope: B. filiformis off Cape Hatteras (588-930 m bathymetric depth) and B. major off Cape Lookout (850-1950 m depth). The sampling area, and particularly the 850 m station where B. filiformis is abundant (mean densities of 59-154 per m2), is believed to receive large inputs of organic material from various sources. This is consistent with the previously observed occurrence of large Bathysiphon species in regions of high food supply. Ten camera sled transects across the eastern U.S. continental slope between 32-degrees-N and 41-degrees-N emphasize the abundance of B. filiformis in the Cape Hatteras area compared with its rarity or absence elsewhere along the continental slope. Box cores, bottom photographs, and direct submersible observations indicate that B. filiformis tubes project above the sediment in an arcuate curve with only the lower 1 cm or so buried. Bathysiphon major adopts a similar orientation but has a greater proportion (50-80%) of the tube buried. The voluminous, dense, granular protoplasm of both species contains biogenic particles (including diatoms, in B. filiformis only), dinoflagellate cysts, fungal remains, pollen grains, tintinnid loricae, polychaete jaws and setae, benthic foraminiferal tests, and fish tooth fragments), suggesting that they feed mainly on material derived from the sediment surface. Submersible observations indicate that B. filiformis is patchily distributed at 100 m scales. Smaller scale dispersion patterns (analyzed from photographs) are generally random but with a tendency to be aggregated at lower densities and uniform at higher densities. A variety of metazoans and foraminifers live epifaunally on the outer surfaces of B. filiformis tubes. The most frequently occurring metazoans were larvae and juveniles of an unidentified gastropod and a tubiculous terebellid polychaete Nicolea sp. The most common epifaunal foraminifers were Tritaxis conica and Trochammina sp. Tubes of B. major, however, are virtually devoid of epifauna. Our results support the view that large, agglutinated rhizopod tests may influence the structure of deep-water benthic communities. However, in the case of Bathysiphon on the North Carolina continental slope, the effect appears limited to taxa directly associated with the foraminiferal tubes.