ANGELO FRAGA BERNARDINO Whales, wood and kelp islands in the deep-sea: ecological succession and species overlap with other chemosynthetic habitats in the Californian continental slope (NE Pacific) Tese apresentada ao Instituto Oceanográfico da Universidade de São Paulo, como parte dos requisitos para obtenção do título de Doutor em Ciências, área de Oceanografia Biológica. Orientador: Prof. Dr. Paulo Yukio Gomes Sumida Co-orientador: Prof. Dr. Craig R. Smith São Paulo 2009 Universidade de São Paulo Instituto Oceanográfico Whales, wood and kelp islands in the deep-sea: ecological succession and species overlap with other chemosynthetic habitats in the Californian continental slope (NE Pacific) Angelo Fraga Bernardino Tese apresentada ao Instituto Oceanográfico da Universidade de São Paulo, como parte dos requisitos para obtenção do título de Doutor em Ciências, área de Oceanografia Biológica. Julgada em ___/___/_____ Prof.(a) Dr.(a) Conceito Prof.(a) Dr.(a) Conceito Prof.(a) Dr.(a) Conceito Prof.(a) Dr.(a) Conceito Prof.(a) Dr.(a) Conceito i INDEX List of Tables ……………………………………………………………….………… ii List of Figures ………………………………………………………………..………. iii Abstract ………………………………………………………………..……………… v Resumo ………………………………………………………………..……………… vi Chapter 1. Introduction ………………………………………………….…………….. 1 1.1. References ..………………………..….………………………………..…........ 6 Chapter 2. Macrofaunal succession in sediments around kelp and wood falls in the 9 deep NE Pacific and community overlap with other reducing habitats 2.1. Introduction ……………………………………………………………………. 10 2.2. Materials and methods ……………...........…………………………………….. 12 2.3. Results ………………………............................................................................. 19 2.4. Discussion …………………………….……………………………………….. 38 2.5. Conclusions …………….……………………………………………………… 46 2.6. References ……….…………………………………………………………….. 46 2.7. Supplementary material …………………………….…………………………. 55 Chapter 3. Infaunal community structure and succession during the sulfophilic stage 57 of a whale carcass in the deep NE Pacific 3.1. Introduction ……………………………….…………………………………… 58 3.2. Material and methods ……………………..…………………………………… 62 3.3. Results ………………………………….……………………………………… 68 3.4. Discussion ……………………………………………………………………... 88 3.5. Conclusions ……………………………………………….…………………... 97 3.6. References …………………………………………………………………….. 98 Chapter 4. The San Clemente cold seep: macrofaunal structure and species overlap 109 with reducing habitats in the deep NE Pacific 4.1. Introduction …………………………………………….……………………… 110 ii 4.2 Study site and methods ………………………..………………..…………….. 113 4.3 Results …………………..……………………………………..……………… 117 4.4 Discusion ……………………………...……………………….………………. 124 4.5 References ……………………………................................…………..……… 132 Chapter 5. Conclusions ………………………………................................................ 141 LIST OF TABLES Table 2.1 ……………………………….……………………………………............... 14 Table 2.2 …………………………………………………………………...……..…... 23 Table 2.3 …………………...……..…..…………………...……..…………………… 24 Table 2.4 ..……………………………………............................................................. 28 Table 2.5 ……………………………………………................................................... 29 Table 2.6 …………………………………………………………………................... 33 Table 2.7 ……………………………………………………………........................... 38 Appendix 2A ………………………………………………………............................ 52 Appendix 2B ………………………………………………………………………… 53 Table S2.1 …………………………………………………………............................ 56 Table 3.1 …………………………………………………………………………….. 70 Table 3.2 ……………................................................................................................. 73 Table 3.3 ……………………………………………………………………………. 79 iii Table 3.4 ……………………………………………………………………………. 80 Table 3.5 ……………………………………………………………………………. 84 Table 3.6 ……………………………………………………………………………. 86 Appendix 3A. ……...................................................................................................... 105 Appendix 3B ……………………………................................................................... 106 Table 4.1 ……………………………………………………………………………. 114 Table 4.2 ……………………………………………………………………………. 119 Table 4.3 ……………………………………………………………………………. 120 Table 4.4 ……………………………………………………………………………. 130 Appendix 4.A ………………………………………………………………………. 137 LIST OF FIGURES Figure 1.1 ………………………………………................................................... 5 Figure 2.1 ............................................................................................................... 13 Figure 2.2. …………………………...................................................................... 20 Figure 2.3. …………………………….................................................................... 22 Figure 2.4. …………….……..….…………………...……..…............................... 23 Figure 2.5. ……………………………………………………………………….... 24 Figure 2.6 ….............................................................................................................. 25 Figure 2.7 .................................................................................................................. 27 Figure 2.8 .................................................................................................................. 28 iv Figure 2.9 ……………………………………........................................................... 29 Figure 2.10 …………………………………............................................................. 30 Figure 2.11 …………………………………............................................................. 31 Figure 2.12 …………................................................................................................. 34 Figure S2.1. ……........................................................................................................ 55 Figure 3.1 ………....................................................................................................... 69 Figure 3.2 ………....................................................................................................... 70 Figure 3.3 ………....................................................................................................... 72 Figure 3.4 ………………………………………………............................................ 74 Figure 3.5 …………………………………………................................................... 76 Figure 3.6 ………………………………………………………............................... 77 Figure 3.7 …………………………............................................................................ 78 Figure 3.8 ………………………................................................................................ 81 Figure 3.9 .................................................................................................................... 82 Figure 3.10 .................................................................................................................. 85 Figure 4.1 ……............................................................................................................ 114 Figure 4.2 ……............................................................................................................ 118 Figure 4.3 ……............................................................................................................ 119 Figure 4.4 ……............................................................................................................ 121 Figure 4.5 ……............................................................................................................ 122 Figure 4.6 ……............................................................................................................ 124 v Abstract Sunken parcels of macroalgae, wood and whale carcasses provide important oases of organic enrichment at the deep-sea floor, but sediment community structure and succession around these habitat islands are poorly evaluated. We experimentally implanted parcels of kelp and wood falls nearby a 30-ton deep-sea whale-fall at 1670 m in the Santa Cruz Basin (SCr; NE Pacific). At each organic island, we aimed to evaluate patterns of organic enrichment and spatial and temporal patterns of macrofaunal community structure and succession over time scales of 0.25 to 7y. Additionally, species overlap between kelp-, wood- and whale-falls with nearby cold-seep communities were investigated. In general, the abundance of infaunal macrobenthos was highly elevated at periods of intense organic enrichment at all organic falls, with decreased macrofaunal diversity and evenness within 0.5 meters of the falls. At kelp and wood falls opportunistic species and sulfide tolerant microbial grazers (dorvilleid polychaetes) abounded after the peak of sedimentary enrichment (0.25y and 1.8y, respectively), while the whale-fall macrofauna was highly abundant from 4.5 to 6.8 y, and was dominated by enrichment opportunist, chemoautotrophic-symbiont-hosting and heterotrophic species grazing sulfur-oxidizing bacterial mats. Sediments around kelp and wood parcels provided low- intensity reducing conditions, which sustain a limited chemoautotrophically-based fauna, with low levels of species overlap among other chemosynthetic habitats in the deep NE Pacific. Whale-fall sediments harbor many species and trophic types not present in background sediments, but there were low levels of species overlap between the whale- fall, cold seeps and hydrothermal vents, explained by differences in biogeochemistry and food webs among these habitats. We conclude that organically enriched sediments around kelp, wood and whale-falls may provide important habitat islands for the persistence and evolution of species dependent on organic- and sulfide-rich conditions at the deep-sea floor and contribute