Abundance data from Aleutians offshore epibenthic trawls from R/V Oceanus OC1606A, OC1707A, 2016-2017 (Kelp Forest Ecosystem Engineer Loss project)

Website: https://www.bco-dmo.org/dataset/729630
Data Type: Cruise Results
Version: 2
Version Date: 2019-01-09

Project
» Collaborative Research: Changes in ecosystem production and benthic biodiversity following the widespread loss of an ecosystem engineer (Kelp Forest Ecosystem Engineer Loss)
ContributorsAffiliationRole
Edwards, MatthewSan Diego State University (SDSU)Principal Investigator
Konar, BrendaUniversity of Alaska Fairbanks (UAF)Co-Principal Investigator
Bland, Aaron S.University of Alaska Fairbanks (UAF)Contact
Copley, NancyWoods Hole Oceanographic Institution (WHOI BCO-DMO)BCO-DMO Data Manager

Abstract
This dataset includes epibenthic community abundance collected offshore by trawls and reported as numbers per 100 square meters.


Coverage

Spatial Extent: N:53.4108 E:-167 S:51.4269 W:-179
Temporal Extent: 2016-06-19 - 2017-07-23

Dataset Description

This dataset includes epibenthic community abundance collected offshore by trawls and reported as numbers per 100 square meters.


Methods & Sampling

Sampling locations were from the Aleutian Archipelago offshore between longitude 173.9 and -167.6 in June 2016 and July 2017.

Trawls were conducted with a 3.05 m plumb-staff beam trawl with a 7-mm mesh and a 4-mm codend liner (Gunderson & Ellis, 1986). For each trawl, the trawl net was towed for approximately 3 minutes on the seafloor with the vessel traveling at 1.5 knots. A temperature-depth recorder was attached to the trawl net to determine effective trawling distances. The start of each trawl was determined by the time at which the trawl net stopped descending in the depth profile, and the end of each trawl was determined by the time the trawl net began ascending. Trawl distances were determined by referencing the GPS coordinates of the research vessel for the start and end times of each trawl event. Occasionally, the trawl net became damaged by rocks during a trawl event, preventing effective sampling after the collision. For these trawls, the collision point was detectable by a sudden decrease in depth of the trawl net, and the effective trawling swath was assumed to be from the beginning of the trawl up to the collision point.

Organisms were sorted and identified to the lowest taxonomic level feasible. Members of each taxonomic group were counted and their damp-biomass (including shells for mollusks and crabs) was determined. Voucher specimens were prepared in 10% buffered formalin for those taxa that could not be identified in the field.

Some large samples were split in half. This is Indicated as the subsaample_factor. A value of 2 (trawl 24) indicates that half of the trawl contents were taken for biomass and count measurements. The biomass and count values in the area-standardized data sheets are estimated by doubling the values recorded for the subsampled portion.


Data Processing Description

BCO-DMO Processing Notes:
- added conventional header with dataset name, PI name, version date
- modified parameter names to conform with BCO-DMO naming conventions
- corrected spelling of 4 taxa to agree with World Register of Marine Species names. See Parameter list below for submitted names, in parentheses.


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Data Files

File
abund_trawl.csv
(Comma Separated Values (.csv), 28.24 KB)
MD5:3d6e418e51a88b0550f379b7b450eec0
Primary data file for dataset ID 729630

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Related Publications

Bland, A., Konar, B., & Edwards, M. (2019). Spatial trends and environmental drivers of epibenthic shelf community structure across the Aleutian Islands. Continental Shelf Research, 175, 12–29. doi:10.1016/j.csr.2019.01.006
Results
Gunderson, D. R., & Ellis, I. E. (1986). Development of a plumb staff beam trawl for sampling demersal fauna. Fisheries Research, 4(1), 35–41. doi:10.1016/0165-7836(86)90026-3
Methods
Konar, B., Edwards, M. S., Bland, A., Metzger, J., Ravelo, A., Traiger, S., & Weitzman, B. (2017). A swath across the great divide: Kelp forests across the Samalga Pass biogeographic break. Continental Shelf Research, 143, 78–88. doi:10.1016/j.csr.2017.06.007
Methods

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Parameters

ParameterDescriptionUnits
Islandsampled Island location unitless
RegionA priori region designation: central; east; west; far-west unitless
Trawl_Distance_mEffective trawling distance based on estimates of trawling start/end locations meters
Trawl_AreaEffective trawling area; trawl distance multiplied by the trawling width of the net (2.26 m) meters^2
Subsample_FactorSubsample indicator. Value of 2 indicates that half of the trawl contents were taken for biomass and count measurements. unitless
Start_LatitudeEstimated location of the research vessel when the trawl net reached the bottom decimal degrees
Start_LongitudeEstimated location of the research vessel when the trawl net reached the bottom decimal degrees
End_LatitudeEstimated location of the research vessel when the trawl net reached the bottom OR the net collided with a rock (ending effective trawling) decimal degrees
End_LongitudeEstimated location of the research vessel when the trawl net reached the bottom OR the net collided with a rock (ending effective trawling) decimal degrees
Start_Date_UTMStarting time for each trawl event; UTC unitless
Samplesample identifier unitless
Acmaea_mitraabundance of Acmaea mitra individuals per 100m^2
Actinaria_sp_1abundance of Actinaria sp. 1 individuals per 100m^2
Actinaria_sp_3abundance of Actinaria sp. 3 individuals per 100m^2
Agonidaeabundance of Agonidae individuals per 100m^2
Agonidae_juvenileabundance of Agonidae; juvenile individuals per 100m^2
Ammodytes_hexapterusabundance of Ammodytes hexapterus individuals per 100m^2
Ammodytidae_spabundance of Ammodytidae sp. individuals per 100m^2
Ampelisca_spabundance of Ampelisca sp. individuals per 100m^2
Amphiophiura_spabundance of Amphiophiura sp. individuals per 100m^2
Amphipodaabundance of Amphipoda individuals per 100m^2
Amphiura_sppabundance of Amphiura spp. individuals per 100m^2
Anonyx_sppabundance of Anonyx spp. individuals per 100m^2
Anoplarchus_insignisabundance of Anoplarchus insignis individuals per 100m^2
Aptocyclus_ventricosusabundance of Aptocyclus ventricosus individuals per 100m^2
Arctonoe_vittataabundance of Arctonoe vittata individuals per 100m^2
Argis_spabundance of Argis sp. individuals per 100m^2
Artedius_lateralisabundance of Artedius lateralis individuals per 100m^2
Aspidophoroides_monopterygiusabundance of Aspidophoroides monopterygius individuals per 100m^2
Asteroidea_no_IDabundance of Asteroidea; un-ID individuals per 100m^2
Atheresthes_sppabundance of Atheresthes spp. individuals per 100m^2
Axinella_blancaabundance of Axinella blanca individuals per 100m^2
Bathyagonus_alascanusabundance of Bathyagonus alascanus individuals per 100m^2
Bathyagonus_nigripinnisabundance of Bathyagonus nigripinnis individuals per 100m^2
Bathymaster_signatusabundance of Bathymaster signatus individuals per 100m^2
Bathypolypus_sppabundance of Bathypolypus spp. individuals per 100m^2
Bathyraja_parmiferaabundance of Bathyraja parmifera individuals per 100m^2
Blepsias_bilobusabundance of Blepsias bilobus individuals per 100m^2
Boltenia_oviferaabundance of Boltenia ovifera individuals per 100m^2
Boreotrophon_sppabundance of Boreotrophon spp. individuals per 100m^2
Brachiopodaabundance of Brachiopoda individuals per 100m^2
Brachyura_no_IDabundance of Brachyura; un-ID individuals per 100m^2
Buccinidaeabundance of Buccinidae individuals per 100m^2
Ceramaster_arcticusabundance of Ceramaster arcticus individuals per 100m^2
Ceramaster_patagonicusabundance of Ceramaster patagonicus individuals per 100m^2
Cheiraster_Luidiaster_dawsoniabundance of Cheiraster (Luidiaster) dawsoni individuals per 100m^2
Chionoecetes_bairdiabundance of Chionoecetes bairdi individuals per 100m^2
Chionoecetes_opilioabundance of Chionoecetes opilio individuals per 100m^2
Chirona_evermanniabundance of Chirona evermanni individuals per 100m^2
Chiton_no_IDabundance of Chiton; un-ID individuals per 100m^2
Chlamys_rubidaabundance of Chlamys rubida individuals per 100m^2
Chrysaora_melanasterabundance of Chrysaora melanaster individuals per 100m^2
Ciliatocardium_ciliatumabundance of Ciliatocardium ciliatum individuals per 100m^2
Clinocottus_spabundance of Clinocottus sp. individuals per 100m^2
Colus_spabundance of Colus sp. individuals per 100m^2
Cottoidea_juvenileabundance of Cottoidea; juvenile individuals per 100m^2
Crangonidaeabundance of Crangonidae individuals per 100m^2
Cranopsis_spabundance of Cranopsis sp. individuals per 100m^2
Crepidula_spabundance of Crepidula sp. individuals per 100m^2
Crossaster_papposusabundance of Crossaster papposus individuals per 100m^2
Cryptacanthodes_aleutensisabundance of Cryptacanthodes aleutensis individuals per 100m^2
Cryptonatica_sppabundance of Cryptonatica spp. individuals per 100m^2
Crystallichthys_cyclospilusabundance of Crystallichthys cyclospilus individuals per 100m^2
Ctenodiscus_spabundance of Ctenodiscus sp. individuals per 100m^2
Cucumaria_fallaxabundance of Cucumaria fallax individuals per 100m^2
Cucumaria_spabundance of Cucumaria sp. individuals per 100m^2
Cup_coral_unidabundance of Cup coral unid. individuals per 100m^2
Dendraster_spabundance of Dendraster sp. individuals per 100m^2
Dendronotus_spabundance of Dendronotus sp. individuals per 100m^2
Diaulula_sandiegensisabundance of Diaulula sandiegensis individuals per 100m^2
Diaulula_spabundance of Diaulula sp. individuals per 100m^2
Diplopteraster_multipesabundance of Diplopteraster multipes individuals per 100m^2
Doridoideaabundance of Doridoidea individuals per 100m^2
Doris_odhneriabundance of Doris odhneri individuals per 100m^2
Doris_spabundance of Doris sp. individuals per 100m^2
Echinarachnius_parmaabundance of Echinarachnius parma individuals per 100m^2
Elassochirus_sppabundance of Elassochirus spp. individuals per 100m^2
Erimacrus_isenbeckiiabundance of Erimacrus isenbeckii individuals per 100m^2
Eumicrotremus_orbisabundance of Eumicrotremus orbis individuals per 100m^2
Eupentacta_spabundance of Eupentacta sp. individuals per 100m^2
Fish_larvae_no_IDabundance of Fish larvae; un-ID individuals per 100m^2
Flabellina_sppabundance of Flabellina spp. individuals per 100m^2
Flatfish_juvenileabundance of Flatfish; juvenile individuals per 100m^2
Flatfish_no_IDabundance of Flatfish; un-ID individuals per 100m^2
Fusitriton_oregonensisabundance of Fusitriton oregonensis individuals per 100m^2
Gadus_chalcogrammusabundance of Gadus chalcogrammus individuals per 100m^2
Gastropoda_sp_1abundance of Gastropoda sp. 1 individuals per 100m^2
Glebocarcinus_oregonensisabundance of Glebocarcinus oregonensis individuals per 100m^2
Glebocarcinus_spabundance of Glebocarcinus sp. individuals per 100m^2
Gobiesocidaeabundance of Gobiesocidae individuals per 100m^2
Gorgonocephalus_eucnemisabundance of Gorgonocephalus eucnemis individuals per 100m^2
Gymnocanthus_galeatusabundance of Gymnocanthus galeatus individuals per 100m^2
Gymnocanthus_tricuspisabundance of Gymnocanthus tricuspis individuals per 100m^2
Halocynthia_aurantiumabundance of Halocynthia aurantium individuals per 100m^2
Hemilepidotus_hemilepidotusabundance of Hemilepidotus hemilepidotus individuals per 100m^2
Hemilepidotus_jordaniabundance of Hemilepidotus jordani individuals per 100m^2
Hemilepidotus_spinosusabundance of Hemilepidotus spinosus individuals per 100m^2
Hemithiris_psittaceaabundance of Hemithiris psittacea individuals per 100m^2
Hemitripterus_boliniabundance of Hemitripterus bolini individuals per 100m^2
Henricia_leviuscula_complexabundance of Henricia leviuscula (complex) individuals per 100m^2
Henricia_sp_1abundance of Henricia sp. 1 individuals per 100m^2
Henricia_sp_2abundance of Henricia sp. 2 individuals per 100m^2
Hermissenda_spabundance of Hermissenda sp. individuals per 100m^2
Hiatella_arcticaabundance of Hiatella arctica individuals per 100m^2
Hippasteria_phrygianaabundance of Hippasteria phrygiana individuals per 100m^2
Hippoglossoides_dubiusabundance of Hippoglossoides dubius individuals per 100m^2
Hippoglossoides_elassodonabundance of Hippoglossoides elassodon individuals per 100m^2
Hippoglossus_stenolepisabundance of Hippoglossus stenolepis individuals per 100m^2
Hippolytidaeabundance of Hippolytidae individuals per 100m^2
Horned_sculpin_maybeabundance of Horned sculpin (?) individuals per 100m^2
Hyas_sppabundance of Hyas spp. individuals per 100m^2
Hypsagonus_quadricornisabundance of Hypsagonus quadricornis individuals per 100m^2
Icelinus_borealisabundance of Icelinus borealis individuals per 100m^2
Isopodaabundance of Isopoda individuals per 100m^2
Kallymeniopsis_sp_driftabundance of Kallymeniopsis sp.; drift individuals per 100m^2
Labidochirus_spabundance of Labidochirus sp. individuals per 100m^2
Labidochirus_splendescensabundance of Labidochirus splendescens individuals per 100m^2
Lacuna_spabundance of Lacuna sp. individuals per 100m^2
Lamellaria_spabundance of Lamellaria sp. individuals per 100m^2
Laminaria_longipes_driftabundance of Laminaria longipes; drift individuals per 100m^2
Leodice_valensabundance of Leodice valens individuals per 100m^2
Lepeta_spabundance of Lepeta sp. individuals per 100m^2
Lepidopsetta_bilineataabundance of Lepidopsetta bilineata individuals per 100m^2
Leptasterias_Hexasterias_alaskensisabundance of Leptasterias (Hexasterias) alaskensis individuals per 100m^2
Leptasterias_Hexasterias_coei_truculentaabundance of Leptasterias (Hexasterias) coei truculenta individuals per 100m^2
Leptasterias_arcticaabundance of Leptasterias arctica individuals per 100m^2
Leptasterias_hylodesabundance of Leptasterias hylodes individuals per 100m^2
Leptasterias_nitidaabundance of Leptasterias nitida individuals per 100m^2
Leptasterias_sppabundance of Leptasterias spp. individuals per 100m^2
Leptocottus_armatusabundance of Leptocottus armatus individuals per 100m^2
Leptychaster_anomalusabundance of Leptychaster anomalus individuals per 100m^2
Leptychaster_arcticusabundance of Leptychaster arcticus individuals per 100m^2
Leptychaster_pacificusabundance of Leptychaster pacificus individuals per 100m^2
Lethasterias_nanimensisabundance of Lethasterias nanimensis individuals per 100m^2
Limneria_prolongataabundance of Limneria prolongata individuals per 100m^2
Liparidaeabundance of Liparidae individuals per 100m^2
Liparis_cyclopusabundance of Liparis cyclopus individuals per 100m^2
Liparis_spabundance of Liparis sp. individuals per 100m^2
Lumpenus_sagittaabundance of Lumpenus sagitta individuals per 100m^2
Lycodes_brevipesabundance of Lycodes brevipes individuals per 100m^2
Malacocottus_zonurusabundance of Malacocottus zonurus individuals per 100m^2
Maxillopodaabundance of Maxillopoda individuals per 100m^2
Metridium_sppabundance of Metridium spp. individuals per 100m^2
Modiolus_modiolusabundance of Modiolus modiolus individuals per 100m^2
Molgula_spabundance of Molgula sp. individuals per 100m^2
Musculus_discorsabundance of Musculus discors individuals per 100m^2
Musculus_spabundance of Musculus sp. individuals per 100m^2
Myoxocephalus_polyacanthocephalusabundance of Myoxocephalus polyacanthocephalus individuals per 100m^2
Myoxocephalus_scorpiusabundance of Myoxocephalus scorpius individuals per 100m^2
Naticidaeabundance of Naticidae individuals per 100m^2
Nemerteaabundance of Nemertea individuals per 100m^2
Neoptilota_sp_driftabundance of Neoptilota sp.; drift individuals per 100m^2
Neptunea_spabundance of Neptunea sp. individuals per 100m^2
Nereididaeabundance of Nereididae individuals per 100m^2
Octopoda_juvenileabundance of Octopoda; juvenile individuals per 100m^2
Odontohenricia_ahearnaeabundance of Odontohenricia ahearnae individuals per 100m^2
Odontohenricia_fisheriabundance of Odontohenricia fisheri individuals per 100m^2
Odontohenricia_spabundance of Odontohenricia sp. individuals per 100m^2
Oenopota_spabundance of Oenopota sp. individuals per 100m^2
Ophiolimna_spabundance of Ophiolimna sp. individuals per 100m^2
Ophiopholis_aculeataabundance of Ophiopholis aculeata individuals per 100m^2
Ophiura_sarsiiabundance of Ophiura sarsii individuals per 100m^2
Oregonia_gracilisabundance of Oregonia gracilis individuals per 100m^2
Orthasterias_koehleriabundance of Orthasterias koehleri individuals per 100m^2
Pagurus_sppabundance of Pagurus spp. individuals per 100m^2
Pandora_glacialisabundance of Pandora glacialis individuals per 100m^2
Pandora_wardianaabundance of Pandora wardiana individuals per 100m^2
Patinopecten_caurinusabundance of Patinopecten caurinus individuals per 100m^2
Pedicellaster_magisterabundance of Pedicellaster magister individuals per 100m^2
Peltodoris_nobilisabundance of Peltodoris nobilis individuals per 100m^2
Peribolaster_biserialisabundance of Peribolaster biserialis individuals per 100m^2
Pleurogrammus_monopterygiusabundance of Pleurogrammus monopterygius individuals per 100m^2
Plicifusus_spabundance of Plicifusus sp. individuals per 100m^2
Pododesmus_macrochismaabundance of Pododesmus macrochisma individuals per 100m^2
Podothecus_accipenserinusabundance of Podothecus accipenserinus individuals per 100m^2
Polychaetaabundance of Polychaeta individuals per 100m^2
Polynoidaeabundance of Polynoidae  individuals per 100m^2
Poroclinus_rothrockiabundance of Poroclinus rothrocki individuals per 100m^2
Psychrolutes_paradoxusabundance of Psychrolutes paradoxus individuals per 100m^2
Pteraster_marsippusabundance of Pteraster marsippus individuals per 100m^2
Pteraster_militarisabundance of Pteraster militaris individuals per 100m^2
Pteraster_spabundance of Pteraster sp. individuals per 100m^2
Pteraster_tesselatusabundance of Pteraster tesselatus individuals per 100m^2
Ptilosarcus_gurneyiabundance of Ptilosarcus gurneyi individuals per 100m^2
Pugettia_gracilisabundance of Pugettia gracilis individuals per 100m^2
Pycnogonidaabundance of Pycnogonida individuals per 100m^2
Pycnopodia_helianthoidesabundance of Pycnopodia helianthoides individuals per 100m^2
Rhamphostomella_costataabundance of Rhamphostomella costata individuals per 100m^2
Rocinela_angustataabundance of Rocinela angustata individuals per 100m^2
Ronquil_no_IDabundance of Ronquil; un-ID individuals per 100m^2
Ronquilus_jordaniabundance of Ronquilus jordani individuals per 100m^2
Rossia_pacificaabundance of Rossia pacifica individuals per 100m^2
Sabellidaeabundance of Sabellidae individuals per 100m^2
Saccharina_sp_driftabundance of Saccharina sp.; drift individuals per 100m^2
Sarritor_frenatusabundance of Sarritor frenatus individuals per 100m^2
Sculpin_no_IDabundance of Sculpin; un-ID individuals per 100m^2
Sebastes_alutusabundance of Sebastes alutus individuals per 100m^2
Sebastes_ciliatusabundance of Sebastes ciliatus individuals per 100m^2
Sergeant_poacherabundance of Sergeant poacher individuals per 100m^2
Serripes_groenlandicusabundance of Serripes groenlandicus individuals per 100m^2
Similipecten_greenlandicusabundance of Similipecten greenlandicus individuals per 100m^2
Sipuncula_sp_1abundance of Sipuncula sp. 1 individuals per 100m^2
Sipuncula_sp_2abundance of Sipuncula sp. 2 individuals per 100m^2
Solariella_sppabundance of Solariella spp. individuals per 100m^2
Solaster_sppabundance of Solaster spp. individuals per 100m^2
Stegocephalus_spabundance of Stegocephalus sp. individuals per 100m^2
Stomphia_spabundance of Stomphia sp. individuals per 100m^2
Strongylocentrotus_sppabundance of Strongylocentrotus spp. individuals per 100m^2
Suberites_sppabundance of Suberites spp. individuals per 100m^2
Tachyrhynchus_spabundance of Tachyrhynchus sp. individuals per 100m^2
Tonicella_spabundance of Tonicella sp. individuals per 100m^2
Triglops_macellusabundance of Triglops macellus individuals per 100m^2
Triglops_pingeliiabundance of Triglops pingelii individuals per 100m^2
Triopha_catalinaeabundance of Triopha catalinae individuals per 100m^2
Tripoplax_trifidaabundance of Tripoplax trifida individuals per 100m^2
Tritonia_sppabundance of Tritonia spp. individuals per 100m^2
Tunicata_sp_1abundance of Tunicata sp. 1 individuals per 100m^2
Tunicata_sp_1aabundance of Tunicata sp. 1 individuals per 100m^2
Urticina_spabundance of Urticina sp. individuals per 100m^2
Velutina_sppabundance of Velutina spp. individuals per 100m^2
Volutopsius_spabundance of Volutopsius sp. individuals per 100m^2


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Instruments

Dataset-specific Instrument Name
Generic Instrument Name
Beam Trawl
Dataset-specific Description
A 3.05 m plumb-staff beam trawl with a 7-mm mesh and a 4-mm codend liner
Generic Instrument Description
A beam trawl consists of a cone-shaped body ending in a bag or codend, which retains the catch. In these trawls the horizontal opening of the net is provided by a beam, made of wood or metal, which is up to 12 m long. The vertical opening is provided by two hoop-like trawl shoes mostly made from steel. No hydrodynamic forces are needed to keep a beam trawl open. The beam trawl is normally towed on outriggers, one trawl on each side. While fishing for flatfish the beam trawl is often equipped with tickler chains to disturb the fish from the seabed. For operations on very rough fishing grounds they can be equipped with chain matrices. Chain matrices are rigged between the beam and the groundrope and prevent boulders/stones from being caught by the trawl. Shrimp beam trawls are not so heavy and have smaller mesh sizes. A bobbin of groundrope with rubber bobbins keeps the shrimp beam trawl in contact with the bottom and gives flatfish the opportunity to escape. Close bottom contact is necessary for successful operation. To avoid bycatch of most juvenile fishes selectivity devices are assembled (sieve nets, sorting grids, escape holes). While targeting flatfish the beam trawls are towed up to seven knots, therefore the gear is very heavy; the largest gears weighs up to 10 ton. The towing speed for shrimp is between 2.5 and 3 knots. (from: http://www.fao.org/fishery/geartype/305/en)


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Deployments

OC1606A

Website
Platform
R/V Oceanus
Start Date
2016-06-17
End Date
2016-07-02
Description
Project: Changes in Ecosystem Production and Benthic Biodiversity

OC1707A

Website
Platform
R/V Oceanus
Start Date
2017-07-18
End Date
2017-07-25
Description
Project: Changes in Ecosystem Production and Benthic Biodiversity


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Project Information

Collaborative Research: Changes in ecosystem production and benthic biodiversity following the widespread loss of an ecosystem engineer (Kelp Forest Ecosystem Engineer Loss)


Coverage: Aleutian Islands Alaska (Attu Island to Unalaska)


NSF abstract:

In many ecosystems the presence of a single dominant species can modify the physical conditions of the environment and alter patterns of biodiversity, nutrient cycling, and primary production. Losses of these "ecosystem engineers" can have profound impacts to how ecosystems function. Coastal kelps provide excellent examples of organisms whose structure modifies the physical characteristics of their habitats (light, nutrients, water motion) and supports enhanced biodiversity. The kelp forests in the coastal waters of the Aleutian Archipelago have suffered large-scale declines over the past several decades. This project will examine how these losses impact patterns of ecosystem production and biodiversity using a combination of techniques ranging from in situ benthic chambers and shipboard incubations to remote sensing using satellite imagery. The results will provide an understanding of how such events may impact this and other ecosystems. This project will support graduate students and will introduce the public to the Aleutian ecosystems in a series of videos. The investigators will also work with a San Diego high school teacher to integrate project findings into classroom activities, and they expect to involve a teacher in their field program.

The investigators will ask two highly integrated questions: 1) How do the widespread losses of kelp forests impact benthic productivity across the Aleutian Archipelago? 2) How do the widespread losses of kelp forests impact benthic biodiversity and community structure across the archipelago? To address these, the investigators will estimate changes to productivity at ten islands where they have historic data on seaweed community composition and estimates of kelp canopy cover. They will use in situ benthic chambers placed in both kelp forests and urchin barrens to measure plot-scale patterns of net ecosystem productivity (NEP), and shipboard incubations to examine net primary productivity (NPP) for the dominant macroalgae. Data for individual species rates of NPP will be scaled by their biomass and combined with in situ plot-scale benthic chamber experiments of whole communities to estimate NEP at the islands visited. These estimates will be scaled up to calculate NEP across the entire archipelago by first extrapolating results from the study sites to entire islands, and then across the archipelago. They will also estimate broad-scale patterns in production by characterizing water column irradiances across the archipelago and modeling NPP using species-level relationships between irradiance and photosynthesis. Coupling these with estimates of water column irradiance and community respiration will allow modeling of NEP across this region. Benthic biodiversity will be assessed using diver surveys and shipboard benthic trawls. Following these activities, satellite remote sensing of the kelp canopies dating back to the 1980s and the investigators' own historical data on benthic macroalgal abundances at these and other islands will be used to estimate the temporal and spatial patterns of change across the archipelago.

For more information see:

Project blog: http://sdsukelp.weebly.com/blog
Project website: http://www.uaf.edu/cfos/research/projects/collaborative-research--/



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Funding

Funding SourceAward
NSF Division of Ocean Sciences (NSF OCE)
NSF Division of Ocean Sciences (NSF OCE)

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