Ecosystem effects of mining
Dr Matt Pinkerton
Presentation to the EPA DMC – Chatham Rock Phosphate Wednesday 15 October 2014 Ecosystem effects of mining
• Direct mortality from mining Direct operation effects • Impacts of the sediment plume • Other direct impacts (noise etc) Effects on individual species Habitat- • Species / life-stages may be mediated impacted by change of habitat effects
Ecosystem effects
Food-web
2 Components Measurements of food-web • Ocean colour remote sensing Primary production • Phytoplankton incubations (NPP) • Underway surface bio-optics • Nutrient analysis Mixed Bacteria, detritus • Flow cytometry layer Viruses • Bacterial activity Micro-zooplankton • Water column structure • Stable isotope analysis • Lipid biomarkers Meso-zooplankton • Zooplankton grazing experiments Meso- Macro-zooplankton • Zooplankton nets Mesopelagic fish • MOCNESS (fine-mesh towed nets) pelagics Thermocline • Midwater trawling Cephalopods • Opening-closing cod-end Meroplankton • Multi-frequency acoustics • Acoustic target strength analyses • Thorium isotopes • Hyperbenthic trawls (Brenke sled) Hyperbenthics Vertical detrital flux • Benthic trawls (beam trawls) • DTIS (Deep-towed Imaging System) Demersals • Multicorer • Sediment traps (moored, floating) Hyperbenthos • Benthic landers
Benthos • … Benthos
3 Day
Dusk
Night
4 • Midwater catch >134 species • >23 mesopelagic fish species
amphipod Cyphocaris richardi amphipod Gammaridae Bathylagidae Bathylagus longirostris amphipod Themisto gaudichaudii Bramidae Brama brama amphipod Vibilia robusta Diretmidae Diretmus argenteus decapod Acanthephyra pelagica Gonostomatidae Margrethia obtusirostra decapod Gennades gilchristi Macrouridae Lepidorhynchus denticulatus decapod Oplophorus novaezeelandiae Myctophidae Diaphus danae decapod Pasiphaea australis Myctophidae Diaphus osterfeldi decapod Pasiphaea balssi Myctophidae Electrona carsbergi decapod Pasiphaea sp. (barnardi) Myctophidae Electrona paucirastra decapod Sergestes arcticus Myctophidae Electrona risso decapod Sergia potens Myctophidae Electrona subaspera euphausiid Euphausia similis Myctophidae Gymnoscopelus piabilis euphausiid Euphausia spinifera Myctophidae Lampanyctodes hectoris euphausiid Nematoscelis megalops Myctophidae Lampanyctus australis jellyfish Mitrocomella sp. Myctophidae Lampanyctus intricarius jellyfish Polaria rufescens? Myctophidae Lampichthys procerus jellyfish Periphylla periphylla Myctophidae Protomyctophum andriashevi mysid Neognathophausia ingens Myctophidae Protomyctophum luciferum pteropod Cymbulia peroni house Myctophidae Protomyctophum normani pyrosoma Pyrosoma sp. Myctophidae Symbolophorus spp. C salp Iasis zonaria Phosichthyidae Photichthys argenteus salp Thetys vagina Platytroctidae Perspasia kapua siphonophora Hippopodius hippopus Serrivomeridae Serrivomer samoensis squid Histioteuthis hoylei Sternoptychidae Argyropelecus gigas squid Iridoteuthis maoria
squid Teuthowenia pellucida Sternoptychidae Argyropelecus hemigymnus Sternoptychidae Maurolicus australis arrow squid Nototodarus sloani Sternoptychidae Sternoptyx obscura warty squid Moroteuthis ingens, M. robsoni Stomiidae Chauliodus sloani red squid Ommastrephes bartrami 5 Stomiidae Idiacanthus atlanticus giant squid Architeuthis Stomiidae Stomias boa boa Chatham Rise: defining the study area for the trophic model
• Organisms have different ranges / movement capabilities • Not one “Chatham Rise food-web” • Trophic model considers large area: 222,800 km2 • Mainly bounded by 1250 m and 250 m depth contours
6 Chatham Rise food-web (trophic) model
7 Trophic importance: overall importance of group in food-web
8 Ecosystem effects of mining
• Direct mortality from mining Direct operation effects • Impacts of the sediment plume • Other direct impacts (noise etc) Effects on individual species Habitat- • Species / life-stages may be mediated impacted by change of habitat effects
Ecosystem effects
Food-web
9 Direct and habitat-mediated impacts Rank Group Location of spawning/early life stages. Likely direct effects of mining/plume on trophic Habitat dependence. productive capacity importance 1 Phytoplankton Whole Chatham Rise; planktonic. No significant impact. Not relevant – no spawning Negligible impact on in/out flows of detritus 2 Detritus benthic at scale of Chatham Rise. Not relevant – no spawning Negligible impact on in/out flows of detritus 3 Detritus water at scale of Chatham Rise. Can reproduce in water column or Probably low overall. 4 Mesozooplankton on/near the seabed. Planktonic. Not known – diverse group. Likely to Not known, but could be high if key species vary between species. Some may in group spawn in/close to mining area. Small demersal require hard benthic substrate for 5 fish spawning/early life stages. Spawn outside Chatham Rise area. Early Low direct impact. 6 Hoki life stages widespread in area. 7 Het. flagellates Whole Chatham Rise; planktonic. Negligible impact at scale of Chatham Rise. Arthropods (e.g. Unlikely to move large distances. May Probably low. prawns & depend on habitat (hard or soft) to 8 shrimps) spawn. Early life stages planktonic. Whole Chatham Rise; very small scale Negligible impact at scale of Chatham Rise. 9 Meiobenthos movement. Whole Chatham Rise; planktonic. Negligible impact on bacteria at scale of 10 Bacteria_water Chatham Rise. Mesopelagic All likely to be pelagic spawners. Early Probably low, but not well known for most 11 fish life stages planktonic. species in group. 10 Direct and habitat-mediated impacts
Rank Group Location of spawning/early life stages. Likely direct effects of mining/plume on trophic Habitat dependence. productive capacity importance Macrozoo May be pelagic or benthic spawners. May Not known, but could be high if key species 12 krill require benthic habitat. Semi-nektonic. in group spawn in/close to mining area. Largely/entirely planktonic and likely to be Probably low. Macrozoo pelagic spawners. Early life stages 13 gelatinous planktonic. Poorly known. Likely to vary between Not known, but could be high if key species species and some may require had benthic in group spawn in/close to mining area. 14 Cephalopods habitat for spawning/early life-stages. Whole Chatham Rise. Small scale Likely low at scale of Chatham Rise for movement. Spawning will depend on group as a whole, but some species in 15 Macrobenthos suitable habitat (hard or soft). group may occur only close to mining areas Ecology not well known. Could make Not known, but could be high if key species Rattails & spawning migrations. Spawning could in group spawn in/close to mining area. 16 ghost sharks depend on hard benthic habitat. Hake spawning not near mining area. Probably low for hake. Not known for other Spawning/juvenile areas of other species species in guild. 17 Hake guild in guild less well known. Whole Chatham Rise Negligible impact on bacteria at scale of Bacteria Chatham Rise. 18 sediment Ling spawning not in mining area. Probably low for ling (though reasons for Spawning/juvenile areas for other species hotspot not known). Not known for other 19 Ling guild in guild less well known. species in guild. 11 Conclusions
• 1. Model / trophic importance limitations Trophic model – no habitat • Not dynamic; not spatially resolved • Small number of trophic groups • Focus on major energy flows
2. Higher ecosystem effects associated with impacts on species with:
3. Anticipated direct/habitat-mediated impacts of mining on 10 of the 11 groups with the highest trophic importances are likely to be low or negligible (because they are widely spread over the Chatham Rise or planktonic)
4. The four trophic groups with the highest direct/habitat-mediated risk from mining and high trophic importances are likely to be:
12 Conclusions
• 1. Model / trophic importance limitations Trophic model – no habitat • Not dynamic; not spatially resolved • Small number of trophic groups • Focus on major energy flows
2. Higher ecosystem effects associated with impacts on species with: • higher trophic importance • providers of structured benthic habitat • spawning / early life stages have particular dependence on the region of mining • known/likely dependence on hard (structured) benthic habitat
3. Anticipated direct/habitat-mediated impacts of mining on 10 of the 11 groups with the highest trophic importances are likely to be low or negligible (because they are widely spread over the Chatham Rise or planktonic)
4. The four trophic groups with the highest direct/habitat-mediated risk from mining and high trophic importances are likely to be:
13 Conclusions
• 1. Model / trophic importance limitations Trophic model – no habitat • Not dynamic; not spatially resolved • Small number of trophic groups • Focus on major energy flows
2. Higher ecosystem effects associated with impacts on species with: • higher trophic importance • providers of structured benthic habitat • spawning / early life stages have particular dependence on the region of mining • known/likely dependence on hard (structured) benthic habitat
3. Anticipated direct/habitat-mediated impacts of mining on 10 of the 11 groups with the highest trophic importances are likely to be low or negligible (because they are widely spread over the Chatham Rise or planktonic)
4. The four trophic groups with the highest direct/habitat-mediated risk from mining and high trophic importances are likely to be:
14 Conclusions
• 1. Model / trophic importance limitations Trophic model – no habitat • Not dynamic; not spatially resolved • Small number of trophic groups • Focus on major energy flows
2. Higher ecosystem effects associated with impacts on species with: • higher trophic importance • providers of structured benthic habitat • spawning / early life stages have particular dependence on the region of mining • known/likely dependence on hard (structured) benthic habitat
3. Anticipated direct/habitat-mediated impacts of mining on 10 of the 11 groups with the highest trophic importances are likely to be low or negligible (because they are widely spread over the Chatham Rise or planktonic)
4. The four trophic groups with the highest direct/habitat-mediated risk from mining and high trophic importances are likely to be: • small demersal fish • hard-bodied macrozooplankton (krill) • cephalopods • rattails & host sharks
15 Conclusions
• 1. Model / trophic importance limitations Trophic model – no habitat • Not dynamic; not spatially resolved • Small number of trophic groups • Focus on major energy flows
2. Higher ecosystem effects associated with impacts on species with: • higher trophic importance • providers of structured benthic habitat • spawning / early life stages have particular dependence on the region of mining • known/likely dependence on hard (structured) benthic habitat
3. Anticipated direct/habitat-mediated impacts of mining on 10 of the 11 groups with the highest trophic importances are likely to be low or negligible (because they are widely spread over the Chatham Rise or planktonic)
4. The four trophic groups with the highest direct/habitat-mediated risk from mining and high trophic importances are likely to be: • small demersal fish • hard-bodied macrozooplankton (krill) • cephalopods • rattails & host sharks
16