Growth, reproduction and survivorship responses to food enhancements for two species of estuarine polychaetes: Streblospio benedicti and Laeonereis culveri

UNCW Author/Contributor (non-UNCW co-authors, if there are any, appear on document)
Meredith Q. Owens (Creator)
Institution
The University of North Carolina Wilmington (UNCW )
Web Site: http://library.uncw.edu/
Advisor
Martin Posey

Abstract: Previous studies evaluating effects of eutrophication in estuarine systems have produced mixed results, sometimes showing weak linkages between resource enhancement and infaunal population responses. A general lack of life history information for many benthic infaunal species, and variable links between trophic controls and population responses, indicate a need to evaluate species-specific responses to specific food resources of varying quantities. This study examined growth, reproduction and survivorship responses to varying food sources for two estuarine polychaetes, Streblospio benedicti and Laeonereis culveri, common to southeastern North Carolina. I compared responses to ten food sources fed at specific quantities: ground Ulva, enhanced benthic microalgae, organic mud slurry, Tetramen fish flakes (high quality food control), azoic sediment and a starvation control for both species, with the additional inclusion of Spartina alterniflora, Phaeosphaeria spartinicola (fungal decomposer), Phaeosphaeria-infused Spartina and an agar control for S. benedicti. Multiple twenty-one day feeding assays were run with 2-3 levels of food, based on N content or volume, fed to field densities of each species. Response variables included survivorship, growth, total length, reproductive condition, and total biomass. S. benedicti showed significant growth and reproductive responses to the benthic microalgae and mud slurry treatments, but little response to other treatments. L. culveri showed variable responses to several treatments. The results suggest that S. benedicti will respond with increased growth, survivorship and oocyte production to enhanced food in the laboratory and may be food-limited in the field. The results for L. culveri illustrate the opportunism utilized by this species and suggest that it may be able to grow similarly among a variety of food sources. The combined results for these species demonstrate the variability in responses to food enhancement and suggest that some aspect of food limitation, either availability or nutrient content, plays a role in regulating growth, abundance and reproduction in benthic communities.

Additional Information

Publication
Thesis
A Thesis Submitted to the University of North Carolina at Wilmington in Partial Fulfillment of the Requirement for the Degree of Masters of Science
Language: English
Date: 2009
Keywords
Polychaeta--Food supply, Polychaeta--Reproduction, Polychaeta--Growth
Subjects
Polychaeta -- Growth
Polychaeta -- Reproduction
Polychaeta -- Food supply

This item contains the following parts:

TitleLocation & LinkType of Relationship
Figureshttp://libres.uncg.edu/ir/uncw/f/owensm2003-2.pdfThe described resource includes the related resource either physically or logically.
Table 5http://libres.uncg.edu/ir/uncw/f/owensm2003-3.pdfThe described resource includes the related resource either physically or logically.