thumbnail

Food-web dynamics and isotopic niches in deep-sea communities residing in a submarine canyon and on the adjacent open slopes

Marine Ecology Progress Series

By:
ORCID iD , ORCID iD , , , and
https://doi.org/10.3354/meps12231

Links

Abstract

Examination of food webs and trophic niches provide insights into organisms' functional ecology, yet few studies have examined trophodynamics within submarine canyons, where the interaction of canyon morphology and oceanography influences habitat provision and food deposition. Using stable isotope analysis and Bayesian ellipses, we documented deep-sea food-web structure and trophic niches in Baltimore Canyon and the adjacent open slopes in the US Mid-Atlantic Region. Results revealed isotopically diverse feeding groups, comprising approximately 5 trophic levels. Regression analysis indicated that consumer isotope data are structured by habitat (canyon vs. slope), feeding group, and depth. Benthic feeders were enriched in 13C and 15N relative to suspension feeders, consistent with consuming older, more refractory organic matter. In contrast, canyon suspension feeders had the largest and more distinct isotopic niche, indicating they consume an isotopically discrete food source, possibly fresher organic material. The wider isotopic niche observed for canyon consumers indicated the presence of feeding specialists and generalists. High dispersion in δ13C values for canyon consumers suggests that the isotopic composition of particulate organic matter changes, which is linked to depositional dynamics, resulting in discrete zones of organic matter accumulation or resuspension. Heterogeneity in habitat and food availability likely enhances trophic diversity in canyons. Given their abundance in the world's oceans, our results from Baltimore Canyon suggest that submarine canyons may represent important havens for trophic diversity.

Study Area

Additional publication details

Publication type:
Article
Publication Subtype:
Journal Article
Title:
Food-web dynamics and isotopic niches in deep-sea communities residing in a submarine canyon and on the adjacent open slopes
Series title:
Marine Ecology Progress Series
DOI:
10.3354/meps12231
Volume:
578
Year Published:
2017
Language:
English
Publisher:
Inter-Research
Contributing office(s):
Wetland and Aquatic Research Center
Description:
15 p.
First page:
19
Last page:
33
Country:
United States
Other Geospatial:
Baltimore Canyon