Presentation on theme: "Beaufort Regional Environmental Assessment"— Presentation transcript:
1 Beaufort Regional Environmental Assessment Marine Fishing Program:Integrated Knowledge of the Canadian Beaufort SeaGood morning, Jim Reist regrets that he could not attend so I will be presenting the talk.Jim Reist (lead PI) and Staff from Arctic Aquatic Research Division, Winnipeg, MBUS-Canada Oil & Gas Forum, Anchorage, Nov 2012Presented by Lisa Loseto
2 Beaufort Regional Environmental Assessment (BREA) Oil and Gas Leases (Source: INAC)BREA announced by INAC in Aug 2010$21.8 Million over 5 yearsTargeted research to support an efficient regulatory processBased on the Beaufort Sea Strategic Regional Plan of Action (BSTRPA)Supported by Inuvialuit, industry and governmentsThe BREA is an initiative of the Government of Canada and Inuvialuit of the Western Arctic designed to identify and fill strategic gaps in knowledge for the Canadian Beaufort Sea.
3 Tier 1 Gap Identified for BREA: Presence & Relevance of Fishes in Deepwater Areas? Project OverviewDeepwater fish project proposed and approved (Sept 2011) by BREA k over 5 years (to March 2015)BREA Proposal Leveraged:PERD (318k to 2012)ESRF (1154k to 2014)DFO IGS (293k over 3 years)ArcticNet (68k ship support)Other PI leveraging (~1158k)DFO in kind (~3000k)Total ~11.5MParticipants: DFO 15 staff (~ 8 ftes) plus 6 ftes (terms); Universities (3 Canada) staff + 6 students + other collaboratorsProject LinkagesMulti-disciplinary ecosystem study with two major themes:Offshore Fishes: diversity, habitat associations & ecosystem rolesCoastal Fishes: linkages among sub-ecosystemsDevelop new knowledge for ‘unknown’ offshore ecosystem, establish key baselines & understand vulnerabilitiesWork complements & extends previous and ongoing DFO work - are coastal and offshore processes and outcomes coupled?Linked with other BREA, ArcticNet projects and US (BOEM) work in BeaufortOne of the Tier 1 gaps identified for BREA was knowledge regarding the offshore marine ecosystem and more specifically the presence and relevance of fishes in deep water areas. Accordingly, we developed a BREA project to address this gap and supplemented that through additional initiatives.The project has been designed as an ecosystem-based study with two major themes – offshore fishes and coastal fishes.The work complements and extends previous research in coastal and shelf areas; it also is designed to determine whether offshore ecosystem components and coastal components are coupled.The work is linked with other BREA projects, ArcticNet activities and with similar work being conducted in the Alaskan Beaufort Sea.A key aspect of this work is that it is the first-ever systematic marine sampling program focused on fishes to a target depth of about 1000m.Completely New Research: Due to previous persistent ice cover, offshore deepwater fishes, their biodiversity & ecological relationships are presently unknown (isolated occurrences only), especially in deep waters – first-ever systematic sampling to 1000m.
4 Overview of Fishes and Their Habitats in the Canadian Beaufort Sea About 70 species of fishes occur in the Canadian Beaufort Sea, however, these are very heterogenous in their distribution and associations with different sub-ecosystems of the overall system. A notable aspect here is that once one moves into depths greater than around 20 meter, fish species tend to become separated in terms of their habitat uses – i.e., those which are associated primarily with the water column are pelagic species, whereas those associated with the bottom are benthic species. Some species (e.g., Arctic cod) can be found in both habitats.Marine fishes occupy a range of trophic levels with the ecosystems thus are pivotal components.Marine fishes also occupy different key habitats during their lives. The various sub-ecosystems or habitat types are also connected through both abiotic processes as well as biotically. Thus from a fish’s perspective, different habitats or areas may be connected through life history associations or by active migrations (either short term or seasonal) by adult fishes.70 fish sp. in the BS, heterogeneous in distribution and association with sub ecosystemsFishes occupy several trophic levels thus are pivotal within ecosystems – e.g., rely on zooplankton for food and in turn are food for seals, whales and sea birdsFishes rely on key habitats at different stages of life – e.g., most larvae -pelagic near surfaceSub-ecosystems/habitats are connected abiotically (e.g., upwellings, currents) and biotically (e.g., passively by fish life stages and actively by migratory adult fishes)
5 BREA Marine Fishes Project Objectives Field survey of offshore area to 1000m depths to establish:a) fish occurrence and community diversity,b) habitat associations, andc) couplings (e.g., foodweb or trophic patterns) within and among components in offshore (~ m) habitats2) Establish the functional relationships within/among offshore and slope, shelf and coastal, benthic and pelagic sub-ecosystems3) Summarize existing knowledge of fish occurrences and habitat associations geo-spatially4) Link offshore research findings with past & ongoing research in the estuary, coastal and the shelf areas in Canadian & US waters5) Establish regional contexts for future monitoring & assessments (e.g., hydrocarbon metabolites, Hg, species diversity and habitat use)The overall objectives of the project are to then establish fish presence and habitat associations in the area, understand their linkages within and among component systems, and thus to establish their vulnerabilties to possible development in the area. We also intend to determine what functional relationships may exists among sub-ecosystems present in the area.This knowledge will establish the regional contexts within which future regulatory decisions can be effectively made and as well provide baselines against with future monitoring might be conducted.IntroductionIn 2004 the Inuvialuit Game Council (IGC) initiated a dialogue with the government and industry regarding the need to address issues surrounding offshore development in the Beaufort Sea.“Beaufort Sea, including deep water fish populations, coastal and marine birds, seabed hazards assessment, distribution and thickness of sea ice, as well as modeling and forecasting of ocean and ice conditions.”"The BREA will provide critical baseline information to Inuvialuit, industry and government for consultations on a comprehensive management approach to the Beaufort Sea ecosystem," said Nellie Cournoyea, Chair/CEO, Inuvialuit Regional Corporation.5
6 Vessel retrofitted with side crane & wet/dry lab spaces The Charter VesselName: F/V Frosti (1979)Home Port: Richmond B.C.Length: 40 mBeam: 8 mDraft: 5 mHorsepower: 1200Gross Tonnage: 454Work was conducted from a chartered fisheries vessel, F/V Frosti modified to fulfill our research needs. A month long late summer science program was planned and executed.Vessel retrofitted with side crane & wet/dry lab spacesHydroacoustics system onboard (NOAA)Science sea trials, calibration, gear lading & shakedown late JulyFrosti – two weeks transit to Canadian Beaufort Sea (arrive 31 July)Science program: 4 August – 4 September, 4 transects each with 7 planned stations (all science components) & hydroacoustics transect with targeted trawling
7 2012 Field sampling- F/V Frosti CCGS Nahidik2006 & 200920082009Four primary transects: Dalhousie (Dal12), Kugmallit (Kug12), Garry (GRY12) and Transboundary (TBS12) – red lines.Three of these, Dal12, Kug12 and Gry12 , are extension of transects sampled during NCMS with Nahidik.Stations along each transect: 20-40, 75, 200, 350, 500, 750, 1000 mAt each station, this was done:CTD-rosette – oceanography and marine productivityPlankton – vertical (multi-plankton sampler) and horizontal (bongo)Boxcore – sediment characterization, infauna3m beam trawl – small bodied demersal fishesWestern IIA otter trawl – All demersal fishes3m beam trawl on Nahidik during years indicated on transects.UAF also using a 3m beam trawl and is testing our this fall for comparability with their net (paired trawls).Once station work along a transect was complete, the transect was re-run (N-S) using hydroacoustics to look for fishes in the water column. Hydroacoustics were “truthed” with bottom and mid-water trawl tows.Hydroacoustics done in collaboration with ArcticNet and DFO-Pacific.All stations completed except 6&7 on TBS12 line. Ledges and humps, etc would not allow for bottom trawling. Other sampling components were completed at these stations.Opportunistically ran a hydroacoustics and CTD transect through Mackenzie Trough to examine upwelling and investigate fish aggregations. No net sampling (done at night) – green line.Three days left after we completed stations work:Conducted additional hydroacoustics work to examine geographic extent of near bottom Arctic Cod aggregation detected on slope (future slide).Some additional net testing also conducted (HCT12) to examine net bias in sampling Arctic Cod, and to systematically assess any change in abundance of Arctic Cod offshore of the 400m isobath – blue line.7
8 Sampling Regime Station sampling (F/V Frosti): Oceanography and water sampling: 4 primary transects x 7 stations/transect = 28 stations; m depths; 475 linear km; 90km transect through key transition zone – Mackenzie Trough)Zooplankton & ichthyoplankton (larval fishes) at 28 stationsSediments & benthic infauna at 27 stationsBenthic macrofauna at 26 stationsFishing – benthic nets at 26 stations (Atlantic Western IIA (WIIA) benthic otter trawl & 3m beam trawl)Hydroacoustics & Water-Column (pelagic) sampling (F/V Frosti):Re-run transect lines for spatial distribution of biomass (~475 linear km)Identify potential aggregations of fish in water columnMid-water and benthic fishing to ‘ground-truth’ hydroacoustics (Cosoms-Swam midwater trawl; 3m beam trawl)Run hydroacoustics ‘section’ across area of highest biomass concentration (i.e., shelf break at ~ m depths – 385 linear km)Coastal Sampling (field camps & local fishers):Sampled 3 estuarine and 3 marine sites near to traditional use areas6 sites for fishes, beluga, other biota; 2 also for oceanographic parametersDirect from slide8
9 Deploying the small 3-meter Beam Trawl Main fishing gear was a large benthic and midwater trawl, however, to ensure comparability to earlier work and to work conducted in Alaska we also deployed a small beam trawl to sample for benthos. Comparisons of catches among trawls indicated that larger fishes tended to avoid the smaller gear, thus some biases exist in terms of size of gear.To allow for comparison of benthic catches with previous NCMS work on Mackenzie Shelf and ongoing Alaskan work, this smaller trawl was deployed.The main benthic trawl was a larger Otter trawl (not shown).Diversity of catches in smaller trawls was similar to that of larger benthic trawl but abundances were less.Larger-bodied fishes tend to avoid these smaller trawls.
10 Fishes Captured: 9258 individuals from 11 families Righteye flounders 113Eelpouts 311Snailfishes 286Overall fishing was minimized to ensure a limited impact in the area. Around 9300 individuals representing 11 families of fishes were captured with most of the catch comprised of the five families shown here. Arctic cod and likely also polar cod represented the vast majority of all fishes captured.Arctic Cod 791510
11 Preliminary Findings - Overall Fish Catch FamilyCommon nameNumber of fishWeight of catch (kg)AgonidaeAlligatorfish1300.27CottidaeSculpins3591.49CyclopteridaeLumpsuckers50.07GadidaeArctic/Polar Cod (mostly B. saida)791551.59Larval fish?0.03LiparidaeSnailfishes2866.09MyctophidaeLanternfishes17PleuronectidaeRighteye flounders113115.18PsychrolutidaeFathead sculpins120.6RajidaeSkates1525.34StichaeidaePricklebacks950.16Unidentified0.11ZoarcidaeEelpouts3116.13Grand Total9258207.74Arctic Cod (and Polar Cod) are largest percentage of catch (85%).Most Arctic Cod caught in pelagic (water column habitats) at ~ m (= halocline transition between fresher warmer Pacific and saltier colder Atlantic waters).Halocline likely is a dynamic feature concentrating pelagic food and fishes.Benthos in shallower depths appears to represent Pacific species (e.g., Bering Flounder, Snow Crab).Deeper stations likely represent Atlantic water masses & associated fishes (e.g., Greenland Halibut, some of these species are new records for area).Much greater diversity in benthic vs pelagic fishes in offshore areas.Many of the groups indicated are benthic in nature; as noted Arctic cod comprised the vast majority of fishes captured numerically but due to their small size comprised a smaller percentage overall by weight. Most cods were captured in pelagic habitat between around 250 and 400 m depths which represents the halocline transition between fresher surface waters and colder deeper waters. The halocline zone likely represents an important dynamic feature that concentrates both fishes and their pelagic foods. Where the halocline zone intersects with the bottom the abundance and diversity of fishes likely is higher than elsewhere, however, this requires more extensive analyses for verification.Benthic fishes (and some invertebrates) present in depths shallower than the halocline zone appear to represent primarily Pacific species such as Bering Flounder. Deeper stations represent water masses originating from the Atlantic Ocean which gyre through the Arctic Basin at depth and approach the Beaufort Slope around 400m and deeper.Some large-bodied fishes were also captured (e.g., 5.5kg Greenland Halibut) and large skates.This table shows the total weight and number of fish caught with the exception of 1 tow*Larval fish do not have a total number associated with them yet and it is the same for fish in the ‘unidentified’ category with a weight but without a total number. These represent a small portion of fish that were not identified at the time they were weighed. Both examples above reflect that data is still being organized. This is true of all the data presented in this document: it is for illustrative purposes only and not meant to reflect final totals of numbers/weights.*the tow that is exempt was a benthic beam trawl (the small 3m net used on the Nahidik) at the Dalhousie transect at the 75m station. It came up as a huge mudbomb which we took a total weight for and subsampled. The subsample had two fish in it, one cod and one aligatorfish. I haven’t included them in the total number of fish as I don’t have their weight – not that their weights would be significant – but I felt it best to exclude the entire trawl for now.11
12 Larger epibenthic species in the Canadian Beaufort Greenland HalibutSnow Crab & Basket StarfishAn idea of the large epibenthic species.Top left: Charlie Ruben and Greenland HalibutTop right: Snowcrab on top of basket starsBottom left: Berring flounderBottom right: Wojecich Walkusz and snowcrabSnow CrabBering Flounder (new record?)12
13 Offshore Demersal Fishes in the Canadian Beaufort Sea Fish community composition shifts with depthThese shifts are coincident with changes in habitat features: depth, salinity, temperature, sediment composition & prey compositionArctic cod present across all offshore habitats but dominate the slope communityBASIN(>450m)Multi-year sea iceWarmer, saltier Atlantic water massAtlantic species presentBenthic catch abundance less dominated by Arctic CodLanternfishesFlatfishesSnailfishesEelpoutsB. SheikoSLOPE( m)Convergence of Pacific & Atlantic water massesThermocline/Halocline concentrate food and fishesDemersal fish community dominated by Arctic codSnailfishesArctic CodB. SheikoAll photos from DFO unless otherwise specifiedSHELF(shallow)Disturbance from seasonal ice scourPacific Water mass with Mackenzie R. sediments & freshwaterShift in fish community composition at 50 m depth(Majewski et al. submitted)EelblenniesAlligatorfish> 50m< 50mStaghorn SculpinB. SheikoDepth is important in explaining fish community structure on the Mackenzie Shelf of the Beaufort Sea (Majewski et al., submitted) with the composition shifting significantly as deeper areas are encountered. These results confirm preliminary findings from the previous work on the shelf conducted through the Nahidik program, but extend that understanding much deeper and further off shore.Benthic diversity overall is much higher than is pelagic diversity in the same areas.We also see shifts in the overall abundance of Arctic cod present in the three general areas as noted earlier.Three sub-habitats are Shelf (<200m), Slope (200 – 500 m), and Basin (>500m)Changes in depth associated with changes in water mass (Pacific/Atlantic/Arctic; Cond/Temp/Depth), bottom type, and prey distributionMost abundant fishes by sub-habitat (from Majewski et al. submitted & BREA 2012 preliminary results):Shelf < 50m: Arctic Staghorn Sculpin, Canadian Eelpout, Arctic Cod (Majewski et al. submitted);Shelf > 50m: Arctic Alligatorfish, Arctic Cod, Stout Eelblenny, Canadian Eelpout, Spatulate Sculpin (Majewski et al. submitted)Shelf: Alligatorfishes, Sculpins, Pricklebacks, Snailfishes (BREA 2012)Slope: Almost entirely Arctic cod (BREA 2012)Basin: Lanternfishes, Flatfishes (Bering Flounder, Greenland Halibut), Cods, Eelpout, Snailfishes*Grossly over-simplified because many of these fishes overlap these habitats, but the most abundant at each habitat type are shown hereDiscuss dynamic nearshore habitat; changes in sediment composition and water mass with depthGoal is to predict distribution of Arctic marine fishes based on habitat association13
14 Benthic Fish Abundance by Habitat SkatesSnailfishAs noted previously, overall benthic diversity is higher than is pelagic fish diversity, however, there appears to be some structuring of benthic diversity with depth at least at the family level with both shallow and deeper areas exhibiting slightly higher diversity than is found on the slope drop off. Whether this also applies to species diversity remains to be seen through future analyses.Show difference in fish diversity across different benthic habitats: Shallow, Slope, and Off slopeAbundance of cod in slope habitatMore biomass in benthic habitats than pelagic habitats – *could be because of net catchability. Fish may be better at avoiding pelagic trawl nets than benthic trawl nets*More diversity in benthic habitats than pelagic habitats (11 families in benthic habitat, 3 in pelagic)Below are the tables associated with each pie chart – in case you find yourself in need of more info:Shallow habitat 20-75m:Alligatorfish/Poachers 85Cods (B. Saida) 547Eelpouts 31Lumpfish 3Sculpins 228Shannies/Pricklebacks 88Snailfish 52Grand Total 1034Slope habitat m:Alligatorfish/Poachers 6Cods (B. Saida) 2468Eelpouts 82Fathead Sculpins 6Lanternfish 2Righteye Flounders 40Sculpins 10Skates 3Snailfish 83Grand Total 2700Off slope habitat m:Cods (B. Saida) 47Eelpouts 67Fathead Sculpins 3Lanternfish 1Righteye Flounders 48Sculpins 8Skates 11Snailfish 36Grand Total 221Righteye FloundersArctic Cod (B. Saida)
15 Pelagic Fish Relative Abundance by Habitat SnailfishOverall as mentioned previously, the pelagic habitat is less diverse (n=3 families) in contrast with benthic habitat (n=11 families).Also there appears to be relatively little difference in diversity across the different habitats by depth. Arctic cod dominates in all locations.Habitat types are based off a slide made for Jim Reist’s presentation to the ADM by E. Carmack.Fish abundance is not broken into adult and larval fish – Near surface (Pacific water mass) is a important habitat for larval fish (Arctic Cod, Snailfish, Righteye Flounders). The data is incomplete at this point and needs to wait for laboratory verification before we can be confidant reporting numbers of larval fish caught.Arctic Cod(B. saida)Lanternfish15
16 Fishes in their Ecosystem Preliminary FindingsFishesOceanographic parameters, physical topography and substrate type determine fish diversityDiversity and biomass are both relatively high in benthic areas and in key transition zones (especially on slope drop off)Arctic/Polar Cod is most abundant and widespread fish species but others important locallySpecies are associated with specific habitats (water masses) but also geographically patterned (east-west)Fish benthic diversity much higher than pelagic diversitySome large-bodied fishes presentSo What?Benthic fishes tend to be more sedentary than pelagic species, e.g., establish local home ranges, thus are vulnerable to local impactsPelagic species tend to be more mobile thus are vulnerable to widespread impactsSome species and habitats are more important than othersFishes in their EcosystemOther aspects of overall study will determine food web (trophic) patterns, energetics, relevance of other key biota, and baselines for monitoring and linkages with coastal systems and higher trophic levels.So, in summary of the preliminary findings.Oceanographic and physical parameters structure fish habitats in this area, and the resulting fish diversity tends to be habitat specific. That is, density and biomass are relatively high in benthic areas and key transition zones. Arctic cod is most abundant and widespread species but others are important locally also.Fish species are associated with specific habitats but also some east to west patterning is apparent.Overall benthic diversity is much higher than is pelagic diversity and some large bodied fishes are present in the benthic fauna.This all matters because of differences between these groups of species: benthic fishes tend to be more sedentary thus one would expect greater vulnerability to local impacts whereas pelagic species are less sedentary and thus more vulnerable to widespread or pervasive impacts. Some species and habitats appear to also be more important than are others.Aspects of the overall study that I have not discussed today will also help determine the relevance of fishes in food web patterns, energetics and the role of other biota,
17 Where to next on fishes and other biota? Sample ProcessingIdentifications confirmedBiological parametersTissues for lab analysesDiversity and abundance over space, habitat and depthLab AnalysesFatty Acids, Hg, PAHs & stress metabolites at DFO WinnipegWater Chemistry at DFO Winnipeg and IOS SidneyLinkages to past coastal & nearshore studies (data analysis)Linkages to coastal components (sample & data analyses)Follow-on CollaborationsStable Isotopes (C,N) – U WaterlooBenthic invertebrates – U Quebec at RimouskiEnergetics & coastal work – U ManitobaHydroacoustics Data Analysis – U Laval (ArcticNet)Linkages with BOEM & U Alaska Fairbanks – matching of outcomesFuture WorkPlanning 2013 BREA field programPlanning/linkages to ArcticNet 2013 field program (hydroacoustics)Integration of relevant data into geospatial planning tools2012 represents the first field year of the overall project and we still have a large amount of work to do with the accumulated samples including processing and gathering of additional data, tissue/sample analyses for follow-on work and to other components of the study. Aspects of this additional work will be undertaken with outside partners and collaborators. We also have to plan for a 2013 field program that will focus in part on the eastern portion of the Canadian Beaufort Sea, execute operational linkages with ArcticNet and also with the ongoing work in Alaska.
18 BREA Frosti Offshore Fishes Crew 2012 Back – Left to Right:Wojciech WalkuszAndy MajewskiLorena EdenfieldGuillaume MeisterhansLaure de MontetyFront – Left to Right:Sheila AtchisonShannon MacPheeCharlie ReubenJane Eert(Present in Spirit: Jim Reist& Rob Young – photos)Thanks and questions.Field Crew aboard F/V FrostiOther project participants at DFO: B. Cress, J. Delaronde, J. Johnson, T. Loewen, L. Loseto, B. Lynn, A. MacHutchon, C. Michel, B. Rosenberg, G. Stern & G. Tomy.Outside direct participants: B. Norcross (UAF), L. Fortier (ULaval), M. Geoffroy (ULaval), M. Power (UWaterloo), J. Treberg (UManitoba), H. Swanson (UWaterloo).
19 Overview of Fishes and Their Habitats in the Canadian Beaufort Sea Beaufort Sea Fishes: ~70 speciesFishes Associate with Areas or Sub-ecosystems and Habitats:Freshwater species some times in freshened nearshore areasSea-run species (chars, whitefishes) seasonally present (summer only) coastally and on shelfCoastal (0- ~20+m depths) marine species tolerant of wide salinitiesNearshore/Shelf (~20-200m) speciesPelagic species (water column)Benthic species (bottom)Slope (~ m) speciesPelagic speciesBenthic speciesOffshore (~ m) speciesAbyssal speciesIce – if present acts as focal point for biota (e.g., feeding area) and also as predatory refuge for some fishesSome Overall ConsiderationsFishes occupy several trophic levels thus are pivotal within ecosystems – e.g., rely on zooplankton for food and in turn are food for seals, whales and sea birdsFishes rely on key habitats at different stages of life – e.g., most larvae are pelagic near surfaceSub-ecosystems/habitats are connected abiotically (e.g., upwellings, currents) and biotically (e.g., passively by fish life stages and actively by migratory adult fishes)About 70 species of fishes occur in the Canadian Beaufort Sea, however, these are very heterogenous in their distribution and associations with different sub-ecosystems of the overall system. A notable aspect here is that once one moves into depths greater than around 20 meter, fish species tend to become separated in terms of their habitat uses – i.e., those which are associated primarily with the water column are pelagic species, whereas those associated with the bottom are benthic species. Some species (e.g., Arctic cod) can be found in both habitats.Marine fishes occupy a range of trophic levels with the ecosystems thus are pivotal components.Marine fishes also occupy different key habitats during their lives. The various sub-ecosystems or habitat types are also connected through both abiotic processes as well as biotically. Thus from a fish’s perspective, different habitats or areas may be connected through life history associations or by active migrations (either short term or seasonal) by adult fishes.
20 Hydroacoustics – Midwater Trawl Sampling Detect pelagic organisms and document their assemblage and biomass within surface and bottom aggregations, with particular focus on Arctic Cod“Truth” targets identified on acoustic echogram with fishing netsWork linked with Laval University (ArcticNet program – Geoffroy & Fortier)200 m400 mThe importance of Arctic cod is emphasized in this echogram from the onboard hydroacoustics system. As noted, after the station sampling was completed for a particular transect that was re-run with the hydroacoustic system to estimate biomass of pelagic biota. Throughout the area surveyed a consistent near-bottom aggregation of fish occurred between around 200 and 400m depths; Netting indicated these primarily Arctic cod possibly with some polar cod also being present. Maxime Geoffroy who is here will present additional information on this.Andy’s notes:Aboard the CCGS Nahidik, we were only able to sample small demersal fishes to depths of approximately 150 m.Preliminary results from the 2012 BREA program indicate that the highest fish biomass is likely between 200 and 400 m depth, and there are distinct shifts in species composition beyond 200 m depth, including larger bodied fishes (e.g., Greenland Halibut).These results highlight the value of the BREA marine fish program.After all stations on a transect were sampled, the transect was re-run using the hydroacoustic system to estimate pelagic biomass.Preliminary results suggest a near-bottom aggregation of Arctic Cod between approximately 200 – 400 m depth spanning the Canadian Beaufort Shelf.Arctic/Polar Cod relatively abundant in pelagic habitats also, but less so in deeper water further offshore.Adult Arctic Cod20
21 Pelagic Sampling & Hydroacoustics Groundtruthing Arctic Cod = typical midwater catch.Pelagic sampling in the midwater column resulted in relatively low overall diversity with Arctic cod dominating the catches as shown here. The presence of meso-pelagic Atlantic species confirmed the faunal associations of the mid-water fishes with the Atlantic.Cosoms-Swam midwater trawl. A cod catch with midwater trawl. Note single lanternfishGlacier Lanternfish (Benthosema glaciale) – new Beaufort Sea record (?); Baffin Bay, North Atlantic, pelagic to 1250m.21
22 Possible Points of Intersection of O&G Development with Marine Fishes Development ActivitySeismic ExplorationShip-based DrillingPelagic ecosystemBenthic ecosystem – habitat lossLand-based DrillingHabitat alteration (borrow pits, islands)Support Activities (ice-breaking, marine traffic)Discharges & minor spillsCatastrophic incidentsCumulative Effects (O&G Activity)Temporal cumulation over life time of populationSpatial cumulation over life historyCumulative Effects (many stressors)Temporal cumulationSpatial cumulationActivity ConsequencesNoise (pelagic & benthic habitats):episodic high dB outputs have uncertain effects on fish hearing and sound communications (e.g., ?fatal close to source; cods attracted to air guns); effects on Arctic Cod a key pelagic species are unknown.Small footprints relative to area and general habitat types suggest limited benthic effects.Chronic noisy sources (e.g., ship operation) at lower dB are unknown but could include exclusion from pelagic habitats.Light effects:unknown/uncertain summer relevance.Ice-breaking and Ice loss/alteration:Habitat or refugium loss (e.g., Arctic Cod)Benthic Habitat loss/alteration:Hard substrate (rocks, gravel fields, etc.) limited in location and extent – removal may affect ‘naturally rare’ species requiring these habitatsCreation of artificial islands would result in small losses of local habitat, but diversity of habitats likely increased (?positive effect)Toxic or Contaminant Effect (episodic release):Localized (spatial & temporal) habitat exclusion of organismsShort-term productivity effectsLimited entrainment and bioaccumulation in ecosystemChronic Toxic or Contaminant Effect (catastrophic release):Extensive (spatial & temporal) habitat exclusionLong-term productivity effectsSignificant entrainment and bioaccumulation in ecosystemNature of the impact affects the fishes differently: so those focused upon local areas likely mean benthic fishes are more susceptible given that they do not move much; pelagic fishes are less susceptible to local effects because they general move more. However, the nature of the impact and its transmission to the fishes may result in many different scales of effect.
23 Overview Other Components: Oceanography (Eert) Conductivity, Temperature & Depth and Water Sampling RosetteTemperature – Dalhousie 12Salinity – Dalhousie 12
24 Zooplankton and fish larvae sampling - MultiNet & Bongos (Walkusz) 200 zooplankton samplesCopepods, Euphausids and Amphipods mainly320 fish larvae collected (1/3 Arctic cod)Spatial & depth analyses for taxonomy, diversity & relative abundance ongoing21 taxa chosen for analysis of foodweb patterns, energetics and baseline contaminant markers (Hg, PAHs)
25 Sediments & Benthic Invertebrates – MacPhee, de Montety & Archambault Characterize bottom substrate as a key habitat feature for benthic marine fishes(% sand, silt, clay, organic content, contaminants & benthic chlorophyll)Characterize benthic fauna as important food resources to marine fishes and other biota (diversity, abundance, biomass, and food-web linkages)Bottom Trawling for EpifaunaNo. Stations Sampled: 29Box Coring for Sediments & InfaunaNo. Stations Sampled: 27Andy’s notes:Beaufort Sea fishes and macrobenthos may show preferences for different sediment typesBox core sampling extends coverage of sediment sampling in Canadian Beaufort Sea to deepwater habitats (500 m +).Bottom dwelling fishes likely feed on bottom dwelling invertebrates such as crabs, sea urchins, shrimp, sea stars, polychaetes – sampled with benthic trawlBox core samples were also processed to characterize infauna and to contribute to studies of trophic dynamics using integrative techniques including stable isotopes and fatty acids25
26 Benthos in the Offshore Canadian Beaufort Sea EpifaunaInfaunaPolychaete worms occurred at all depths and substrate typesThemistoPolar ShrimpCephalopodsSquidSnow CrabEpifauna Notes from Laure:Species richness was similar among the three easternmost transect, however the dominant species group seems to vary considerablyThe transect West of Herschel Island seems to have some species not encountered on the others transect as Psolus sp, Sclerocrangon ferox, Lebbeus PolarisAt this point, we do not know if this variability is significant and if it is governed by sediment type, food availability or other environmental variables. Further results, identification of organisms and sediment analyses will be carried out in home labs.Also from Shannon: Note that some commercially important species were sampled (Snow Crab, Polar Shrimp)Infauna Notes from Shannon:Polychaetes are an important component of the benthic food web, and occurred across all habitat types (Shelf/Slope/Basin, depths, substrate types)Sediments at the Easternmost stations were heavily influenced by the Mackenzie River and had high clay content; sites west of Herschel Island had more sand and gravel (grain size data not yet in, but this is a fair statement, it was pretty obvious)Gastropods and bivalves were more apparent at sites with higher sand and gravel contentBivalves & Gastropods present in sediment with higher % sand and gravelAsteridaeMany invertebrates sampled are important food sources to fishes and marine mammalsStable isotope and fatty acid analyses will be used to assess benthic-pelagic coupling and the ecological role of benthic invertebratesEstablish baselines for contaminants (Hg & PAHs) from key speciesPhotos: Laure de Montety (UQAR) except Themisto, R. Hopcroft26
27 Primary Productivity - Michel & Meisterhans Spatial distribution of surface chlorophyll aNote strong influence of Mackenzie RiverTBS12 transectNote low productivity offshore waterSection distance (km)
28 Structural and Functional Relationships of Mercury: Baselines & Patterns (Stern) Mercury exists in a range of chemical forms as it cycles through the Arctic environment; mercury bioaccumulates and biomagnifies within ecosystems and biota.HgTo date, virtually no information is available on biomagnification and bioaccumulation of mercury in deep water and shelf adult fishes.Key baselines established for future reference.
29 PAHs and metabolites in Beaufort Sea Biota (Tomy) Establish baseline levels of Poly Aromatic Hydrocarbons (PAH) and their metabolites in fish from coastal waters in the Beaufort SeaPAHs can be readily metabolized by many fish species; the resulting metabolites pose a greater threat to fish health than do the parent compoundsBackground values will be established for indicators of fish health (e.g., thyroid hormone levels, levels of oxidative stress) due to exposure to PAHs and their toxic metabolitesBaselines will provide for future comparative studies
30 Fish Habitats in the Beaufort Sea in Summer Three Groups of Fish HabitatsWater column (pelagic) with layers of different densities (salinities):Fresh river inputs (Mackenzie R.) – 0-10m (highly mixed waters 0-30 psu)Mixed layers (SML/WML) on the shelf – 10-60mPacific (BSSW/BSWW) water – mSharp halocline (LHW) – mAtlantic Water (AW) – mBottom (benthic) types:Fine muds and clays (Mackenzie eastwards)Gravel patches & muds (western areas)Bedrock further offshore in westCoastal & nearshore surface (0-5+m): highly freshened (5-20 psu) narrow band west and east, wide near Mackenzie outflowCombinations of salinity, temperature, depth, and/or bottom type determine fishes present in pelagic (water column) or benthic (bottom) habitats.(E. Carmack)Three groups of habitats can be delineated: water column or pelagic zones, benthic or bottom types, and coastal zones. Depending upon where one is in the Canadian Beaufort Sea, these may each be further differentiated into water layers, different bottom types and also different mixed zones of fresh and marine water on the shelf.Fishes ‘see’ these habitat differences and exhibit preferences for certain habitat types, thus fishes themselves then associate with the different habitats. This association then results in heterogeneity in the distributions of fishes among habitats but also means that, because habitat impacts tend to be specific to sites, the vulnerabilities of the fishes differ with respect to different perturbations in their environments.General (approximate) characteristics of water masses in the Beaufort Sea.Plate A. The water masses stratify into layers according to their density, which is driven by salinity given the small range of temperature difference. Density is directly related to salinity; as salinity increases, density also increases. SML = Summer Mixed Layer; WML = Winter Mixed Layer; BSSW = Bering Sea Summer Water; BSWW = Bering Sea Winter Water; LHW = Lower Halocline Water; and AW = Atlantic Water.Plate B. The conservative characteristics of temperature and salinity allow the various water masses to be identified by their position on a ts-plot. (Graphs courtesy of E. Carmack, personal communication.)