Topical and trophic relationships in a boring polychaete–scallop association: fatty acid biomarker approach

Abstract

The association between the Japanese scallop Patinopecten yessoensis and the scallopshell-boring polychaete worm Polydora brevipalpa was investigated in the natural environment. Fatty acid analyses were performed on the scallop, polychaete, and potential food materials available in the environment, with the aim of determining the main food sources of these animals and the trophic relationships between species. The scallop and the polychaete showed a similarity in their fatty acid compositions. High concentrations of 20:5n-3 and 14:0, substantial concentrations of 16:2n-4, 16:3n-4, and 16:4n-1, and ratios of 16:1n-7 to 16:0 close to 1 indicated significant contributions of diatoms in the diets of both mollusk and polychaete. Detectable levels of 18:4n-3 suggest that dinoflagellates also contributed to the diet of the animals. The fatty acid markers showed that the scallop and polychaete feed extensively on a mixed, but probably diatom-dominated phytoplankton diet. Additionally, the elevated level of bacterially derived fatty acids and saturated (mainly 18:0) acids in polychaete lipids point to an additional dietary source, detritus and bacteria. Elevated amounts of 22:6n-3 and 18:1n-9 in the scallop digestive gland are indicative of zooplankton consumption. The similarity of the diets is a major determinant of the feeding competition between these species in the community. The decrease in the scallop internal volume concurrent with an increase in the degree of shell occupation by polychaetes suggests a reduction in water-filtering potential by the scallop. Linear regressions of the degree of polychaete occupation against scallop weight and shell height revealed negative relations in both cases. With high levels of shell occupation by polychaetes, the commensal relationship between scallop and polychaete acquires some elements of parasitism. KEY WORDS: Community · Inter-specific relationships · Trophic biology · Fatty acids · Mollusks · Polychaetes Resale or republication not permitted without written consent of the publisherMar Ecol Prog Ser 394: [125][126][127][128][129][130][131][132][133][134][135][136] 2009 dominant among such organisms. For instance, in muddy bottom areas of Peter the Great Bay of the Sea of Japan, the shell surface of the benthic mobile Japanese scallop Patinopecten (= Mizuhopecten) yessoensis (Jay) is free of epibionts (Silina 2002), and generally only one species (the boring polychaete Polydora brevipalpa Zachs) occurs in association with the scallop shell (Silina 2003(Silina , 2006.The effect of boring worms on oysters, abalones, scallops, clams and mussels have mainly been studied in mariculture conditions. Some researchers have shown that boring worms affect the health and growth of mollusks (Lleonart et al. 2003), whereas others did not find such an effect (Caceres-Martinez & Tinoco-Orta 2001, Calvo et al. 2001, Handley & Bergquist 1997. We investigated the association of the Japanese scallop Patinopecten yessoensis and the polychaete worm Polydora brevipalpa that inhabit...

Characterization of forage fish and invertebrates in the Northwestern Hawaiian Islands using fatty acid signatures: species and ecological groups

“…FA trophic markers have long been recognized as efficient tools in studies of marine food webs (Sargent et al 1989, Budge et al 2002, 2006, Dalsgaard et al 2003. Recent studies have demonstrated that FAs can be successfully used to elucidate feeding ecology and trophic relationships of marine fish (Drazen et al 2009, Stowasser et al 2009) and invertebrates (Silina & Zhukova 2009, Spilmont et al 2009). However, northern/temperate and abyssal marine ecosystems have been the focus of most research efforts, and FA data regarding trophic interactions in tropical marine ecosystems are scarce (reviewed by Dalsgaard et al 2003).…”

Sex change in scallop Patinopecten yessoensis: response to population composition?

“…Starvation of Yeso scallop in wild populations from the study area has never been mentioned in a literature. This scallop feeds on a mixed, but diatom-dominated phytoplankton diet (Silina & Zhukova, 2009). According to some estimates, the diatom genera Thalassiosira, Coscinodiscus, Pseudo-nitzschia, Chaetoceros, Thalassionema, Rhizosolenia, and Skeletonema account for about 60–90% of the total phytoplankton biomass in the study area.…”

Fatty Acids in the Barents Sea Red King Crab Hemolymph

“…Спектр питания камчатского краба в губе Дальнезеленецкая довольно широк (Павлова, 2008; Дворецкий, 2012а): он включает более 40 видов донных беспозвоночных, среди которых наиболее часто встречаются двустворчатые и брюхоногие моллюски, морские ежи, морские звезды, офиуры, ракообразные и полихеты. Исследования биохимического состава донных животных показали, что содержание жирных кислот сильно варьирует в зависимости от таксономического статуса объекта (Howell et al, 2003;Drazen et al, 2008;Silina, Zhukova, 2009). Например, концентрация ДГК в тканях ракообразных и иглокожих обычно выше, чем в тканях полихет (Howell et al, 2003;Drazen et al, 2008), а концентрация арахидоновой кислоты у моллюсков почти в три раза выше, чем у полихет (Silina, Zhukova, 2009).…”

“…Исследования биохимического состава донных животных показали, что содержание жирных кислот сильно варьирует в зависимости от таксономического статуса объекта (Howell et al, 2003;Drazen et al, 2008;Silina, Zhukova, 2009). Например, концентрация ДГК в тканях ракообразных и иглокожих обычно выше, чем в тканях полихет (Howell et al, 2003;Drazen et al, 2008), а концентрация арахидоновой кислоты у моллюсков почти в три раза выше, чем у полихет (Silina, Zhukova, 2009). Таким образом, можно с высокой долей вероятности утверждать, что основную роль в изменчивости жирнокислотного состава гемолимфы отдельных особей краба имеют не физиологические параметры животных, а то, какие объекты были употреблены ими в пищу.…”