Wide distributional range of marine sponges along the Pacific Ocean

Abstract

Widespread geographic distribution of sponges should be rare, mainly because of the low dispersal capacity of their larvae and asexual products. Here we investigate the potential wide-scale distribution range in one marine sponge, Gelliodes wilsoni, that has been spread widely around the Pacific Rim by shipping. The species was originally described from the Philippines (western Pacific Ocean) by Wilson in 1925 as Gelliodes fibrosa. Recently, similar specimens have been collected from Guam (western Pacific Ocean), Hawaii, Palmyra Atoll (central Pacific Ocean), Acapulco Bay and Baja Peninsula (eastern Pacific Ocean). This species now appears to be widely distributed across the Pacific Ocean, and this distribution seems unlikely to have resulted from an extremely high dispersal capability; it is most likely the result of centuries of trans-Pacific shipping. We also propose the new name G. wilsoni for the species G. fibrosa originally described by Wilson because the same name was previously used by Dendy in 1905 to describe a species from Sri Lanka, which is morphologically different from the species described by Wilson. The case of G. wilsoni is not unique because several sponges (discussed here) have similar distribution patterns across the Pacific (at locations more than 10,000 km apart). This suggests an east–west connectivity and that widespread distribution in sponges is indeed possible, albeit the result of human activities. In an increasingly connected world our research highlights the importance of understanding connectivity across oceanic scales in order to predict where invasive species are likely to occur.

Keywords:

• Anthropogenic biogeography
• widespread distribution
• human dispersal
• Pacific Ocean
• sponges

Published in collaboration with the University of Bergen and the Institute of Marine Research, Norway, and the Marine Biological Laboratory, University of Copenhagen, Denmark

Published in collaboration with the University of Bergen and the Institute of Marine Research, Norway, and the Marine Biological Laboratory, University of Copenhagen, Denmark

Acknowledgements

We thank Clara Ramírez Jauregui for help with the literature, Felipe Gil Armendariz, Santiago Valenzuela and Akatzin Barba for their assistance in field sampling and Yolanda Hornelas (ICML) for the SEM photographs. We would also like to thank Rob Toonen for his help with the lab work and collection of samples in Hawaii and Gareth Williams and William Arlidge for field support and collection in Hawaii and Palmyra. The work in Mexican waters has been partially supported by the project SEP-CONACYT-102239 and by the permission DGOPA.00978.120209.0457 conferred for SAGARPA for the collection of the samples. Specimens from La Paz were supported by the project INE/ADE-013/2011. We are also grateful to The Nature Conservancy (TNC), United States Fish and Wildlife Service (USFWS) and the institutes involved in the Palmyra Atoll Research Consortium (PARC) for providing access to the refuge and logistical support, without which this work would not have been possible. The work at Palmyra was conducted under the USFWS special use permit 12533-08004, with funding for Ingrid Knapp being provided by Victoria University of Wellington. We also thank James T. Carlton for his suggestions to improve this manuscript. This is PARC publication number PARC-0094.

Notes

Published in collaboration with the University of Bergen and the Institute of Marine Research, Norway, and the Marine Biological Laboratory, University of Copenhagen, Denmark