Evidence of Professor Les Watling on Behalf of Greenpeace New Zealand

Before the Environmental Protection Authority

Application for Marine Consent by Chatham Rock Phosphate Ltd

IN THE MATTER the Exclusive Economic Zone and OF Continental Shelf (Environmental Effects) Act 2012

AND

IN THE MATTER An application by Chatham Rock OF Phosphate Ltd for a marine consent application to mine phosphorite nodules from the crest of the Chatham Rise and return sediment to the seabed .

Evidence of Professor Les Watling on behalf of Greenpeace New Zealand, Incorporated Kiwis Against Seabed Mining Incorporated and Deep Sea Conservation Coalition, Incorporated

Dated 11 September 2014 STATEMENT OF EVIDENCE OF LES WATLING

Qualifications and experience

1. My name is Les Watling. I am a Professor in the Department of Biology at the University of Hawaii at Manoa where I have worked since 2006. Previous to that I was at the University of Maine, USA, taking up my position there in 1976. I have undertaken extensive research on benthic communities in both shallow and deep waters, as well as the taxonomy of several invertebrate groups including crustaceans, octocorals, and sponges.

2. I hold a Bachelor of Science in Zoology from the University of Calgary (Canada), a Master of Science from the University of the Pacific, California, USA, and a Ph.D. from the University of Delaware, USA.

3. My current research includes analysis of bottom communities on seamounts, analysis of fisheries data for deep-sea fish species, identification and description of new species of deep-water octocorals, crustaceans, and carnivorous sponges, analysis of global patterns of biogeography of deep-water octocorals, analysis of trawling impacts on bottom communities, and understanding of the relationship between invertebrates and bottom sediment communities.

4. I have published 150 scientific papers, edited 7 books, and written one small popular book. My papers have generally been evenly split between studies of benthic communities and sediments, and studies broadly construed as invertebrate biology including taxonomy.

5. I have participated in 30 oceanic research cruises (including 19 as Chief Scientist) studying all aspects of the deep-sea benthos. Of the 30 cruises, 18 involved using submersibles (including Alvin) and ROVs to image bottom communities and collect samples. In all I have logged more than 300 hours on the seafloor at deep sea depths.

6. In my taxonomic work I have described 50 new species of crustaceans, 10 new species of deep-sea octocorals, and 1 new carnivorous sponge. In addition, I have created 11 new genera of crustaceans and one new genus of octocoral.

7. I have served as President of The Crustacean Society, an international organization devoted to the study of crustaceans, have been awarded a Pew Fellowship in Marine Conservation, and have had 7 new species and one new genus named in my honour. Evidence of Professor Les Watling

8. At the University of Hawaii I teach courses in seamount ecology and fisheries, marine ecology, and high seas fisheries, all at the graduate level. I also serve as the Graduate Chair of Zoology. At the University of Maine I taught graduate-level courses in Invertebrate Zoology, Biological Oceanography, Ecology of Marine Sediments, and Biostatistics.

9. I confirm that I have read the 'Code of Conduct for Expert Witnesses' as contained in Schedule 4 of the Judicature Act 1908 and the Environment Court Consolidated Practice Note 2011. I agree to comply with these Codes of Conduct. Except where I state otherwise, this evidence is within my sphere of expertise and I have not omitted to consider material facts known to me that might alter or detract from the opinions I express.

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Outline of this evidence

10. This statement of evidence addresses the effects of the proposed seabed mining on the benthic ecosystem. It is concerned with two major potential impacts of the mining process. These are, first, the removal of the coral Goniocorella dumosa and its impact on the overall biodiversity of the central part of Chatham Rise, and second, the changes to the benthic habitat as a result of the return of non-phosphatic material to the seabed.

Key points in this evidence

11. The proposed mining activity involves removal of the benthic substrate, particularly the phosphorite nodules, on which a number of organisms live including the protected deep water scleractinian (“hard”) coral species, Goniocorella dumosa . Hard corals normally live in areas that have very low rates of sedimentation. Thus, even minor levels of sediment deposition will affect the ability of this coral to feed and reproduce, and could cause the coral to become stressed to the level of dying.

12. Goniocorella dumosa grows in the form of small thickets, the branches creating space in which other species live. The community of which G. dumosa is a dominant member contains a wide diversity of other epifaunal species such as byrozoans, sponges, and ascidians. These groups all have a similar life style, that is, they live attached to the phosphorite nodules and feed on water- borne particles. Due to their colonial or otherwise three-dimensional form they also provide habitat for a large number of other species. None of the studies in the area have identified any of the species associated with these suspension feeders so we have no way to know how many species might be displaced when the habitat-forming species are removed.

13. The sediment in the nodule area contains a very high fraction of biologically-derived calcium carbonate. These sediment particles do not have the hardness of siliciclastic minerals so will probably become pulverized during the washing and sorting process used to extract the nodules. As a result the returned sediment will most likely have a much higher fraction of very fine silt-sized particles than the sediment in which the nodules are found.

14. The proposed mining activity will involve the removal of phosphate nodules from the surrounding sediment, their separation from non-phosphatic sediment occurring on the mining vessel, with the unwanted material returned to the sea floor through a discharge pipe terminating about 10 m above bottom. The returned residual sediment will have characteristics that are far different from the sediments in which the nodules reside. This sediment will have smaller mean particle size and much

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higher water content than the in situ sediments and so will be more mobile and probably will spread farther than the settling model predicts.

15. As a result the animal community of the mined area, and for some unknown distance away from the mined area, will be impacted. In the mined area, the animal community will be removed along with the sediment and nodules, but in some undefined area surrounding the mined sediments, the impacts will be associated with the returned sediment particles. The returned sediment will differ considerably in its characteristics from the source sediment, especially with respect to the stratification of grains (larger grains settle first, silts, and then clays later) and lower bulk density as a result of added water. In addition, the water content of the silt and clay layer of the returned sediment will be much higher than in the source sediment, so the recovery of the animal community to this returned sediment will not occur until the returned sediment loses water (described by the term self-weight consolidation).

16. Because of the scale of the mining project it is unlikely that any attempts at restoration of the bottom community will be realistic. In the soft-sediment area, there sediment will be too “soupy” for a long time due to issues of self-consolidation. In the coral area, the hard substrate will be removed, so the only mechanism for restoring the coral area will be to replace the mined nodules with some other hard substrate. As will be shown below, this will be impractical and expensive.

The Importance of Goniocorella dumosa

17. One of the most important structure-forming, and thus habitat-creating, species on the Chatham Rise is the scleractinian coral, Goniocorella dumosa . This coral occurs over the whole of the Rise, which models suggest is almost ideal habitat for this species (Davies and Guinotte 2011; Tracey et al. 2011), in fact, to the near exclusion of other scleractinians. Tracey et al. (2011) attribute this to a preference for steep seabed slopes, seamounts, slow seabed orbital velocity (i.e., not impacted heavily by storm waves), fast tidal current speeds, and low levels of particulate organic carbon flux. Rowden et al. (Appendix 16) show Goniocorella abundance to be highest throughout the centre of the permit area where they grow attached to the phosphorite nodules, in contrast to the habitat suitability models that suggest the NW part of the permit area and areas along the NW edge of Chatham Rise to be most favourable for G. dumosa growth, primarily due to the likelihood of exposed hard substrate being found in those areas.

18. In the permit area, the Goniocorella dumosa grows in the form of small thickets, with numerous, often adjoining, groups of highly intertwined branches emanating from a nodule or other hard

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substrate. “These communities satisfy the definition of a ‘coral thicket’, and are considered to be ‘sensitive environments’ under the regulations of the Continental Shelf and EEZ Environmental Effects Act. Goniocorella dumosa is also a protected species, as it is belongs to the taxon Scleractinia – which is one of a group of deep water corals afforded protection by the Wildlife Act” (Rowden et al. Appendix 16, page 74).

19. Goniocorella dumosa provides significant habitat for a large number of species, most of which are not, or are poorly, documented (Beu and Climo 1974, Rowden et al. Appendix 16), and some of which have specializations that take advantage of the coral as a substrate (e.g., Emarginula striatula documented in Beu and Climo 1974; Iphitella neozelandica lives in empty calyces (coral polyp “cups”) of G. dumosa , Beu 1978). “Colonies of Goniocorella dumosa provide niches for a diverse assemblage of organisms including other scleractinians, stoloniferans, sponges, stylasterids, bryozoans, polychaetes, ophiuroids, asteroids, gastropods, bivalves, anemones, and foraminiferans (Cairns, 1995)”: from Probert et al. 1997, p. 34). In fact, Rowden et al. (Appendix 16) note that the assemblage characterized by high abundances of G. dumosa also had high numbers of sponges, bryozoans, and ascidians, all of which like G. dumosa , are suspension feeders. Thus, the nodules provide the essential substrate for a whole suite of colonial organisms and associated suspension feeders. Like Lophelia pertusa in the North Atlantic (Roberts et al. 2006), G. dumosa is an indicator of an assemblage of species that are not well documented but will contribute to the overall biodiversity of the central part of Chatham Rise.

20. Loss of Goniocorella dumosa habitat will occur as a result of two aspects of the mining activity. First, and most obviously, there will be direct impacts as an unknown but significantly large amount of coral will be removed during the mining activity since the species tends to occur on the phosphorite nodules (Rowden et al. Appendix 16). Second, indirect impacts will be associated with sediment disturbance and mobility of returned sediments after nodule processing (see below). Both direct and indirect impacts are likely to have strong secondary effects on the overall biodiversity of the central part of the Chatham Rise.

21. The ability of deep water scleractinians to clear themselves of settled sediment particles is currently open to debate because there is very little information, and none on G. dumosa . Shallow water corals generally suffer from multiple problems (e.g., enhanced energy expenditures, poor tissue and skeletal growth, polyp mortality) when covered with even small amounts of sediment, but this may be due to the fact that the sediment cuts off light that is needed for the associated zooxanthellae (see review in Larsson and Purser 2011) and the coral expends a great deal of energy trying to get rid of

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it. The deep water scleractinian, Lophelia pertusa , however, was able to handle small amounts of settled sediment or drill cuttings (containing barite) in aquarium experiments, but showed some of the same effects as shallow water corals under a regime of repeated sediment addition leading to moderately high levels of sediment accumulation (6 to 19 mm). Brooke et al. (2009) showed that L. pertusa colonies could handle sediment loads for the first two days, but then polyp mortality increased in a step-wise fashion as the experiment continued.

22. The fact that G. dumosa occurs in greatest abundance where particulate organic carbon flux is low and tidal current speeds are high suggests that it does not handle settling sediment particles very well. In fact, the literature on deep water scleractinians barely mentions suspended sediment loads, most likely because the species all occur in areas where suspended particle loads are very low, especially relative to continental shelf waters (see review in Roberts et al. 2009). Rather, the point is made indirectly by noting that the deep water species need a hard, stable substrate on which to settle, attach to, and grow. By implication, then, the substrate needs to be bare and not covered with even a thin veneer of settled sediment.

Settling and movement of non-phosphatic sediment returned to the bottom

23. The sediment in the area to be mined area will be fluidized using high pressure water jets and then moved to the surface through a riser pipe. Turbulence in the riser pipe can be expected to further break up muddy aggregations and free the phosphatic nodules from the surrounding sediment. On the mining vessel, the material will be processed through a series of “logwashers” and sieves to separate the nodules from the non-phosphatic sediment. The CRP Consent document notes that no chemicals will be used to effect this separation but there is no indication in the Environmental Impact Assessment of whether surface water will be added to the slurry.

24. The sediment in the mining area is composed of about 40% calcium carbonate, with additional small aggregates of glauconite, in addition to siliciclastic sands and silts and phosphorite nodules. The sediment grain size is important for modelling the distribution of the returned sediment plume. The modelling parameters for the Deltares Model used a mined sediment composition of 44% and 8% particle size smaller than silt (60 um) and clay (4 um) respectively (CRP Consent document, p. 271).

25. The model does not appear to account for the possibility that grain size could change due to the mechanical effects of both the sediment fluidization process, the turbulence within the riser pipe, or

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the sorting and sieving on the surface vessel. Since the calcium carbonate component of the sediment is most likely contributed by foraminiferans, bivalve shells, and coral fragments, one might predict that the mechanical roughness of the mining procedure would result in the fracturing of a large proportion of the carbonate particles resulting in a significance change in grain size. Thus it is quite possible that the returned sediment would have a much higher proportion of silt and clay sized particles than the source sediment.

26. The model output assumes that the grain size of the returned sediment will be equivalent to that of the mined sediment but it also suggests there will be “full segregation of all particle sizes” (CRP Consent Appl. EIA, p. 271). The segregation by particle size is a result of Stokes Law of settling velocities, where particle settling is a second order function of particle size (Allen 1985). Larger particles settle much faster than finer particles so the resultant deposition of returned sediment will be graded by size with the smallest grain sizes at the surface.

27. It is well known that natural sediments are usually well mixed with numerous smaller grains surrounding larger grains. Note that common geological measures of grain size are actually measures of the total weight of the particles within a size class and do not directly reflect the number of grains in that size class; thus there may be several orders of magnitude more particles in the fine silt range than in the fine sand range (Freidman et al. 1992). Depending on the rate at which new sediment grains are delivered to a particular area of the bottom, the sediments will be more or less compact. Water content (reflecting sediment porosity) is a common measure of that compaction (Allen 1985), especially with respect to the ability of small invertebrate animals to use the sediment as habitat (Thayer 1975). Water content varies with the sediment grain mixture, but as a general rule is higher in sediment that is composed of a high proportion of silt and clay (Freidman et al. 1992).

28. The returned sediment should then have two properties that will make it unsuitable for recolonization by benthic invertebrates. First, the smaller silt and the clay grains (notwithstanding the fact that the proportion of grains in this size class may well be much more numerous) will settle last and so will be at the sediment-water interface, with the larger silt and sand grains below. Second, the fine silt and clay layer will have much higher water content than the original sediment, most likely above 90%. This is similar to what is often found in areas of storm deposits or other sources of rapid sedimentation.

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29. There is very little literature on the problem of high water content for infaunal sediment dwellers, but this is a property of that should be of interest to benthic ecologists. However, it has been investigated formally only by Thayer (1975). Palaeontologists have been interested in the subject for a long time as a way to explain certain morphological features of sediment-dwelling animals, such as spines on brachiopods, for example. As the water content of the sediment increases, the bearing load decreases. Large or dense animals, especially those with shells, will then sink deeper within sediments that are more watery. Because oxygen concentrations in the sediment pore water are near zero within a few mm below the sediment-water interface, animals living in high water content sediment must then have some way of “floating”, or have developed other structures, such as long siphons, that allow them to stay in contact with the overlying oxygenated water. For example, the two cumacean species in the genus Watlingia Gerken (2010), which are known only from the Chatham Rise, live at the sediment-water interface. These species are very small (3.5-4.5 mm total length) but because of their calcareous carapace, would not be able to inhabit watery sediments without sinking too far ( a few mm) below the sediment-water interface. This problem will be faced by all the very small organisms, from amphipods (which dominate one of the infauna communities) to larvae looking for a place to settle.

30. Larval settlement will be a crucial factor in the recolonization of the sediment returned to the dredge area. It seems to be assumed that the overall bulk density, and thus the water content, of the settled sediment will be equivalent in its functional properties to the source sediments. But this will hardly be the case. The overall bulk density of the returned sediment is estimated to be 1,234 kg/m 3 (=1.234 g/cc, a more typical expression of wet bulk density in marine sediments), whereas the source sediment is much more compact, with an average bulk density of 1,750 kg/m 3 (=1.75 g/cc). Mineral grains have a typical density of 2.65 g/cc, while organic particle density is about 1.25 g/cc (Avnimelech et al. 2001). Porosity (roughly equal to water content) can be calculated as 1-(bulk density/particle density) x100. A bulk density of 1.23 g/cc then would imply a water content of 54%, compared to the source sediment of 34%. Unfortunately we do not have estimates of the bulk density of the upper layer of the returned sediment, which will consist primarily of finer grains and will likely have a water content much higher than the bulk density estimate for the sediment as a whole. Larvae looking for a place to settle are on the order of 1 mm in size or smaller. They need to descend through the benthic boundary layer into the diffusive sublayer in order to test the quality of the sediment to see if it is suitable. If it is not, the larva will re-enter the water column and try to find another more suitable location (Butman 1987). But, for many species, this search cannot go on

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for long, so a large are of bottom that consists of watery sediment will result in larvae dying before they find suitable substrate.

31. Contrary to CRP Consent Application EIA section 8.6.4.2, most of the recolonization studies cited are not comparable to the situation here. The shallow water dredging studies deal with the recolonization of the dredge track, which may differ considerably from the surface layer of sediments that were removed, especially with respect to food quality of the remaining sediment itself. However, Watling et al. (2001) showed that in shallow water the biological productivity of the water column can replenish the food quality of the sediment in the dredge track and replenishment of macrofauna can occur both from migrating adults as well as settlement of larvae, depending on season. Similar processes are likely to operate in deeper water but over longer time scales. But the central issue not dealt with here is the recolonization of the spoil pile (in shallow water) or the returned sediment in deeper water. Spoil piles take some time to “consolidate” during which they lose water as the grains continue to settle under the pull of gravity.

32. Section 8.4.6 (p. 291) deals with sediment resuspension. The Deltares model predicted that the “critical erosion shear stress required to erode the cohesive surface sediments (clay and silt fractions) is predicted to be higher than the bed shear stresses under ambient conditions.” The problem with this result is that because the returned sediment will be sorted due to settlement such that the finer grains will be at the sediment-water interface, and because the fine-grained layer will have much higher water content than the ambient sediments, the returned sediments will not be very “cohesive.” As a consequence, with tidal current velocities reaching 30 – 45 cm/s (CRP Consent Document p. 80), these fine-grained sediments will be readily remobilized and will most likely eventually be spread well beyond the mined area.

33. In response to EPA requests 17 and 18, the CRP document states that the sediments “had a range of (bulk) densities between 1,210 to 2,160 kg/m 3, with the average around 1,750 kg/m 3” and that the bulk density of “the discharged sediment will be 1,234 kg/m3.” It is calculated that the shear stress under normal conditions will not be strong enough to move the settled material. As a result “once settled, it is very unlikely that any of the discharged sediment will be resuspended.” This conclusion does not account for the fact that the bulk density of the sediment will change with depth in the deposited sediment layer, being much lower at the surface than at 10 cm or deeper due to the sorting of the grains as they settle. With the finer grains in the surface layer, and with water content therefore also very high, the shear stress required to move the grains will be much lower than for

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the consolidated source sediments (Allen 1985; Stow 1994). It is likely then that settled sediment may move around much more than the model would predict.

Restoration of the Bottom Community

34. The recent literature suggests that anthropogenic uses of deep-sea communities should include plans for restoration of the disturbed areas (van Dover et al. 2013, Barbier et al 2014). While one could see the possibilities of restorative activities in an environment that is spatially restricted, such as hydrothermal vents, or cold vent fields, restoration in the deep sea is for the most part likely to be impractical for a variety of reasons. In the soft sediment area, the returned sediments will have much higher water content than the source sediment, so will be unsuitable for colonization as already noted. In addition, the time for sediment de-watering, known as self-consolidation, seems to be very hard to predict, but could easily be on the order of decades. It is also likely that as the sediment is consolidating, it will be subject to shear forces generated by tidal currents, so may well tend to move around.

35. Restoration of the nodule area is even more problematic. The bottom sediments and nodules will be removed and loose, highly watery sediment will be returned. In order to prepare the area for coral recolonization, solid substrate blocks will need to be placed in the now “soupy” sediments. To keep from sinking below the sediment-water interface, these blocks will need to be quite large, at least 0.5 m high (since 0.3 to 0.5 m of sediment will be removed, that will be approximately the depth of the sediment fill). Such large blocks will not be easily placed. The mined area is initially planned to cover 820 km 2, or 820 million m 2. The number of blocks to be placed will be very high, assuming one block per m 2, which is a density much lower than the current nodule density. Assuming the nodule restoration area to cover only 20% of the mining area, for example, the number of blocks would still be 164 million. Without going in to the details of how this would be done, I think it is possible to see that the cost of placing these blocks, even if dropped from a surface ship (not the preferred method), would be prohibitive.

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References

Allen, J.R.L. 1985. Principles of Physical Sedimentology. George Allen and Unwin, Boston.

Avnimelech, Y. G. Ritvo, L, Meijer, M. Kochba. 2001. Water content, organic carbon and dry bulk density in flooded sediments. Aquacultural Engineering 25: 25-33.

Barbier, E.B., D. Moreno-Mateos, A.D. Rogers, J. Aronson, L. Pendleton, R. Danovaro, L.-A. Henry, T. Morato, J. Ardron, C.L. Van Dover. 2014. Protect the deep sea. Nature 506: 475-477.

Beu, A.G. 1978. Habitat and relationships of Iphitella neozelaniea (Dell) (Gastropoda: Epitoniidae), New Zealand Journal of Marine and Freshwater Research 12(4): 391-396.

Beu, A.G., and F.M. Climo. 1974. Mollusca from a recent coral community in Palliser bay, Cook Strait. New Zealand Journal of Marine and Freshwater Research 8(2): 307-332.

Brooke, S.D., M.W. Holmes, C.M. Young. 2009. Sediment tolerance of two different morphotypes of the deep-sea coral Lophelia pertusa from the Gulf of Mexico. Marine Ecology Progress Series 390: 137-144.

Butman, C.A. 1987. Larval settlement of soft-sediment invertebrates: the spatial scales of pattern explained by active habitat selection and the emerging role of hydrodynamical processes. Oceanogr. Mar. Biol. An. Rev. 25: 113-165.

Cairns, S. D. 1995. The marine fauna of New Zealand: Scleractinia (Cnidaria: Anthozoa). New Zealand Oceanographic Institute Memoir, 103, 210 pp.

Davies, A.J. and J.M. Guinotte. 2011. Global habitat suitability for framework-forming cold-water corals. PLoS ONE 6(4): e18483.

Friedman, G.M., J.E. Sanders & D.C. Kopaska-Merkel. 1992. Principles of Sedimentary Deposits. Macmillan Publishing Company, New York.s

Gerken, S. 2010. Watlingia, a new genus (Cumacean: Lampropidae) from the waters of New Zealand. Journal of Crustacean Biology 30: 296-306.

Larsson, A.I. and A. Purser. 2011. Sedimentation on the cold-water coral Lophelia pertusa: cleaning efficiency from natural sediments and drill cuttings. Marine Pollution Bulletin 62: 1159-1168.

Probert P.K., D.G. McKnight, S.L. Grove. 1997. Benthic invertebrate bycatch from a deep-water trawl fishery, Chatham Rise, New Zealand. Aquatic Conservation: Marine and Freshwater Ecosystems 7: 27-40.

Roberts, J.M., A.J. Wheeler, A. Freiwald. 2006. Reefs of the deep: the biology and geology of cold-water ecosystems. Science 312: 543-547.

Roberts, J.M., A. Wheeler, A. Freiwald, S.D. Cairns. 2009. Cold-Water Corals, The Biology and Geology of Deep-Sea Coral Habitats. Cambridge University Press.

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Stow, D.A.V. 1994. Deep sea processes of sediment transport and deposition. Pp. 257-292, In: K. Pye (ed.) Sediment Transport and Depositional Processes. Blackwell Scientific Publications.

Thayer, C.W. 1975. Morphologic adaptations of benthic invertebrates to soft substrata. Journal of Marine Research 33: 177-189.

Tracey, D.M., A.A. Rowden, K.A. Mackay, T. Compton. 2011. Habitat-forming cold-water corals show affinity for seamounts in the New Zealand region. Marine Ecology Progress Series 430: 1-22.

Van Dover, C.L., J. Aronson, L. Pendleton, S. Smith, S. Arnaud-Haond, D. Morato-Mateus, E. Barbier, D. Billett, K. Bowers, R. Danovaro, A. Edwards, S. Kellert, T. Morato, E. Pollard, A. Rogers, R. Warner. 2014. Ecological restoration in the deep sea: desiderata. Marine Policy 44: 98-106.

Watling, L., R.H. Findlay, L.M. Mayer, D.F. Schick. 2001. Impact of a scallop drag on the sediment chemistry, microbiota, and faunal assemblages of a shallow subtidal marine benthic community. Journal of Sea Research 46: 309-324.

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