Trends in Ecology & Evolution
ReviewRethinking the Role of Salps in the Ocean
Section snippets
Why is the Role of Salps in Marine Ecosystems Underappreciated?
Scientists and the public alike are interested and intrigued by salps, with the media variously describing them as ‘aliens’, ‘jelly-balls’, ‘globs’, ‘buckets of snot’, and ‘sea-walnuts’. Salps belong to the class Thaliacea, a group of pelagic gelatinous zooplankton that also include doliolids and pyrosomes (Box 1). While many similarities and many of the conclusions from this review will apply across all thaliaceans, for this review we focus on salps because information on their roles in the
Why Have Salps Been Ignored? Overturning Longstanding Misconceptions
Given their unusual biology and ecology (Box 2; Figure 2), why have salps been ignored? We contend that a series of misconceptions have led to the perception that salps are unimportant components of marine food webs and this has hindered research in this area.
Avenues for Future Research
Piette and Lemaire [68] reviewed 250 years of research into tunicate evolutionary and developmental biology, and explored how modern genomics such as molecular phylogenetic analyses have helped to revise salp phylogeny, taxonomy, and development. There remain, however, many unanswered ecological and ecosystem questions (see Outstanding Questions), which we discuss below. Many of these avenues will be equally applicable to other thaliaceans (doliolids and pyrosomes).
Concluding Remarks
In this review we have highlighted the importance of salps in the marine ecosystem and have suggested avenues to stimulate future research into this fascinating but understudied group. Salps are ubiquitous, important contributors to higher trophic levels and biogeochemical cycles, with considerable potential to sequester carbon. The future of research into salp ecology depends on the use of novel sampling and experimental techniques designed specifically for ephemeral gelatinous organisms. It
Acknowledgments
This research was funded by Australian Research Council Discovery Grants DP0880078 and DP150102656. N.H. was funded by an Australian Postgraduate Award and a UNSW Evolution and Ecology Research Centre Skills Transfer Award. We thank Oliver Berry for comments on the manuscript and Kira Askaroff for graphic design. Mark Baird was generous with ideas and initiated our salp research. Non-salp images in Box 3 were provided by the Integration and Application Network, University of Maryland Center for
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