Articles | Volume 22, issue 4
https://doi.org/10.5194/bg-22-959-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-22-959-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
19 Feb 2025
Research article |
| 19 Feb 2025
| 19 Feb 2025
Including the invisible: deep depth-integrated chlorophyll estimates from remote sensing may assist in identifying biologically important areas in oligotrophic coastal margins
Renée P. Schoeman
CORRESPONDING AUTHOR
Centre for Marine Science and Technology, Curtin University, Bentley, Western Australia 6102, Australia
Christine Erbe
Centre for Marine Science and Technology, Curtin University, Bentley, Western Australia 6102, Australia
Robert D. McCauley
Centre for Marine Science and Technology, Curtin University, Bentley, Western Australia 6102, Australia
Cited articles
Australian Bureau of Meteorology: Southern hemisphere monitoring, http://www.bom.gov.au/climate/enso/?ninoIndex=nino3.4&index=nino34&period=weekly#tabs=Pacific-Ocean&pacific=History (last access: 13 February 2025), 2025.
Bahlburg, D., Thorpe, S. E., Meyer, B., Berger, U., and Murphy, E. J.: An intercomparison of models predicting growth of Antarctic krill (Euphausia superba): The importance of recognizing model specificity, PLoS One, 18, e0286036, https://doi.org/10.1371/journal.pone.0286036, 2023.
Baldry, K., Strutton, P. G., Hill, N. A., and Boyd, P. W.: Subsurface chlorophyll-a maxima in the Southern Ocean, Front. Mar. Sci., 7, 671, https://doi.org/10.3389/fmars.2020.00671.
Barbieux, M., Uitz, J., Gentili, B., Pasqueron de Fommervault, O., Mignot, A., Poteau, A., Schmechtig, C., Taillandier, V., Leymarie, E., Penkerc'h, C., D'Ortenzio, F., Claustre, H., and Bricaud, A.: Bio-optical characterization of subsurface chlorophyll maxima in the Mediterranean Sea from a Biogeochemical-Argo float database, Biogeosciences, 16, 1321–1342, https://doi.org/10.5194/bg-16-1321-2019, 2019.
Bock, N., Cornec, M., Claustre, H., and Duhamel, S.: Biogeographical classification from the global ocean from BGC-Argo floats, Global Biogeochem. Sci., 36, e2021GB007233, https://doi.org/10.1029/2021GB007233, 2022.
Boettger, D., Robertson, R., and Brassington, G. B.: Verification of the mixed layer depth in the OceanMAPS operational forecast model for Austral autumn, Geosci. Model Dev., 11, 3795–3805, https://doi.org/10.5194/gmd-11-3795-2018, 2018.
Cade, D. E., Kahane-Rapport, S. R., Wallis, B., Goldbogen, J. A., and Friedlaender, A. S.: Evidence for size-selective predation by Antarctic humpback whales, Front. Mar. Sci., 9, 747788, https://doi.org/10.3389/fmars.2022.747788, 2022.
Chai, T. and Draxler, R. R.: Root mean square error (RMSE) or mean absolute error (MAE)? – Arguments against avoiding RMSE in the literature, Geosci. Model Dev., 7, 1247–1250, https://doi.org/10.5194/gmd-7-1247-2014, 2014.
Chen, M., Pattiaratchi, C. B., Ghadouani, A., and Hanson, C.: Seasonal and inter-annual variability of water column properties along the Rottnest continental shelf, south-west Australia, Ocean Sci., 15, 333–348, https://doi.org/10.5194/os-15-333-2019, 2019.
Chen, M., Pattiaratchi, C. B., Ghadouani, A., and Hanson, C.: Influence of storm events on chlorophyll distribution along the oligotrophic continental shelf off south-western Australia, Front. Mar. Sci., 7, 287, https://doi.org/10.3389/fmars.2020.00287, 2020.
Chiswell, S. M., Gutiérrez-Rodríguez, A., Gall, M., Safi, K., Strzepek, R., Décima, M. R., and Nodder, S. D.: Seasonal cycles of phytoplankton and net primary production from Biogeochemical Argo float data in the south-west Pacific Ocean, Deep-Sea Res. Pt. I, 187, 103834, https://doi.org/10.1016/j.dsr.2022.103834, 2022.
Cornec, M., Claustre, H., Mignot, A., Guidi, L., Lacour, L., Poteau, A., D'Ortenzio, F., Gentili, B., and Schmechtig, C.: Deep chlorophyll maxima in the global ocean: Occurrences, drivers and characteristics, Global Biogeochem. Cy., 35, e2020GB006759, https://doi.org/10.1029/2020GB006759, 2021.
Cresswell, G. R. and Golding, T. J.: Observations of a south-flowing current in the southeastern Indian Ocean, Deep-Sea Res. Pt. A, 27, 449–466, https://doi.org/10.1016/0198-0149(80)90055-2, 1980.
Croll, D. A., Marinovic, B., Benson, S., Chavez, F. P., Black, N., Ternullo, R., and Tershy, B. R.: From wind to whales: Trophic links in a coastal upwelling system, Mar. Ecol. Prog. Ser., 289, 117–130, https://doi.org/10.3354/MEPS289117, 2005.
Cullen, J. J.: The deep chlorophyll maximum: Comparing vertical profiles of chlorophyll a, Can. J. Fish. Aquat. Sci., 39, 791–803, https://doi.org/10.1139/f82-108, 1982.
Cullen, J. J.: Subsurface chlorophyll maximum layers: Enduring enigma or mystery solved?, Ann. Rev. Mar. Sci., 7, 207–239, https://doi.org/10.1146/annurev-marine-010213-135111, 2015.
de Boyer Montégut, C., Madec, G., Fischer, A. S., Lazar, A., and Iudicone, D.: Mixed layer depth over the global ocean: An examination of profile data and a profile-based climatology, J. Geophys. Res.-Oceans, 109, C12003, https://doi.org/10.1029/2004JC002378, 2004.
Double, M. C., Andrews-Goff, V., Jenner, K. C. S., Jenner, M. N., Laverick, S. M., Branch, T. A., and Gales, N. J.: Migratory movements of pygmy blue whales (Balaenoptera musculus brevicauda) between Australia and Indonesia as revealed by satellite telemetry, PLoS One, 9, e95378, https://doi.org/10.1371/journal.pone.0093578, 2014.
Erbe, C., Verma, A., McCauley, R., Gavrilov, A., and Parnum, I.: The marine soundscape of the Perth Canyon, Prog. Oceanogr., 137, 38–51, https://doi.org/10.1016/j.pocean.2015.05.015, 2015.
Fearns, P. R., Twomey, L., Zakiyah, U., Helleren, S., Vincent, W., and Lynch, M. J.: The Hillarys transect (3): Optical and chlorophyll relationships across the continental shelf off Perth, Cont. Shelf. Res., 27, 1719–1746, https://doi.org/10.1016/j.csr.2007.02.004, 2007.
Feinberg, L. R. and Peterson, W. T.: Variability in duration and intensity of euphausiid spawning off central Oregon, 1996–2001, Prog. Oceanogr., 57, 363–379, https://doi.org/10.1016/s0079-6611(03)00106-X, 2003.
Feng, M., Meyers, G., Pearce, A., and Wijffels, S.: Annual and interannual variation of the Leeuwin Current at 32° S, J. Geophys. Res., 108, 3355, https://doi.org/10.1029/2002JC001763, 2003.
Feng, M., Waite, A. M., and Thompson, P. A.: Climate variability and ocean production in the Leeuwin Current system off the west coast of Western Australia, J. R. Soc. West Aust., 92, 67–81, 2009.
Feng, M., Wijffels, S., Godfrey, S., and Meyers, G.: Do eddies play a role in the momentum balance of the Leeuwin Current?, J. Phys. Oceanogr., 35, 964–975, https://doi.org/10.1175/JPO2730.1, 2015.
Fernand, L., Weston, K., Morris, T., Greenwood, N., Brown, J., and Jickells, T.: The contribution of the deep chlorophyll maximum to primary production in a seasonally stratified shelf sea, the North Sea, Biogeochemistry, 113, 153–166, https://doi.org/10.1007/s10533-013-9831-7, 2013.
Fisher, J. L., Menkel, J., Copeman, L., Shaw, C. T., Feinberg, L. R., and Peterson, W. T.: Comparison of condition metrics and lipid content between Euphausia pacifica and Thysanoessa spinifera in the northern California Current, USA, Prog. Oceanogr., 188, 102417, https://doi.org/10.1016/j.pocean.2020.102417, 2020.
Frolov, S., Ryan, J. P., and Chavez, F. P.: Predicting euphotic-depth-integrated chlorophyll-a from discrete-depth and satellite-observable chlorophyll-a off central California, J. Geophys. Res.-Oceans, 117, C05042, https://doi.org/10.1029/2011JC007322, 2012.
Gieskes, W. W. C. and Kraay, G. W.: Continuous plankton records: Changes in the plankton of the North Sea and its eutrophic southern bight from 1948 to 1975, Neth. J. Sea Res., 11, 334–364, https://doi.org/10.1016/0077-7579(77)90014-X, 1977.
Gordon, H. R. and McCluney, W. R.: Estimation of the depth of sunlight penetration in the sea for remote sensing, Appl. Optics, 14, 413–416, https://doi.org/10.1364/AO.14.000413, 1975.
Graff, J. R. and Behrenfeld, M. J.: Photoacclimation responses in subarctic Atlantic phytoplankton following a natural mixing-restratification event, Front. Mar. Sci., 5, 209, https://doi.org/10.3389/fmars.2018.00209, 2018.
Groom, S., Sathyendranath, S., Ban, Y., Bernard, S., Brewin, R., Brotas, V., Brockmann, C., Chauhan, P., Choi, J. K., Chuprin, A., Ciavatta, S., Cipollini, P., Donlon, C., Franz, B., He, X., Hirata, T., Jackson, T., Kampel, M., Krasemann, H., Lavender, S., Pardo-Martinez, S., Mélin, F., Platt, T., Santoleri, R., Skakala, J., Schaeffer, B., Smith, M., Steinmetz, F., Valente, A., and Wang, M.: Satellite ocean colour: Current status and future perspective, Front. Mar. Sci., 6, 485, https://doi.org/10.3389/fmars.2019.00485, 2019.
Hanson, C. E., Pattiaratchi, C. B., and Waite, A. M.: Seasonal production regimes off south-western Australia: Influence of the Capes and Leeuwin currents on phytoplankton dynamics, Mar. Freshwater Res., 56, 1011–1026, https://doi.org/10.1071/MF04288, 2005a.
Hanson, C. E., Pattiaratchi, C. B., and Waite, A. M.: Sporadic upwelling on a downwelling coast: Phytoplankton responses to spatially variable nutrient dynamics off the Gascoyne region of Western Australia, Cont. Shelf. Res., 25, 1561–1582, https://doi.org/10.1016/j.csr.2005.04.003, 2005b.
Hanson, C. E., Pesant, S., Waite, A. M., and Pattiaratchi, C. B.: Assessing the magnitude and significance of deep chlorophyll maxima of the coastal eastern Indian Ocean, Deep-Sea Res. Pt. II, 54, 884–901, https://doi.org/10.1016/j.dsr2.2006.08.021, 2007a.
Hanson, C. E., Waite, A. M., Thompsson, P. A., and Pattiaratchi, C. B.: Plankton community structure and nitrogen nutrition in Leeuwin Current and coastal waters off the Gascoyne region of Western Australia, Deep-Sea Res. Pt. II, 54, 902–924, https://doi.org/10.1016/j.dsr2.2006.10.002, 2007b.
Hellessey, N., Johnson, R., Ericson, J. A., Nichols, P. D., Kawaguchi, S., Nicol, S., Hoem, N., and Virtue, P.: Antarctic krill lipid and fatty acid content variability is associated to satellite derived chlorophyll a and sea surface temperatures, Sci. Rep.-UK, 10, 6060, https://doi.org/10.1038/s41598-020-62800-7, 2020.
Hobday, A. J. and Hartog, J. R.: Derived ocean features for dynamic ocean management, Oceanography, 27, 134–145, https://doi.org/10.5670/oceanog.2014.92, 2014.
Hodson, T. O.: Root-mean-square error (RMSE) or mean absolute error (MAE): when to use them or not, Geosci. Model Dev., 15, 5481–5487, https://doi.org/10.5194/gmd-15-5481-2022, 2022.
Hovis, W. A., Clark, D. K., Anderson, F., Austin, R. W., Wilson, W. H., Baker, E. T., Ball, D., Gordon, H. R., Mueller, J. L., El-Sayed, S. Z., Sturm, B., Wrigley, R. C., and Yentsch, C. S.: Nimbus-7 coastal zone color scanner: System description and initial imagery, Science, 210, 60–63, https://doi.org/10.1126/science.210.4465.60, 1980.
Huot, Y., Babin, M., Bruyant, F., Grob, C., Twardowski, M. S., and Claustre, H.: Relationship between photosynthetic parameters and different proxies of phytoplankton biomass in the subtropical ocean, Biogeosciences, 4, 853–868, https://doi.org/10.5194/bg-4-853-2007, 2007.
IMOS: IMOS – Australian Facility for Ocean Gliders (ANFOG) – delayed mode glider deployments, https://portal.aodn.org.au, last access: 26 July 2023.
IOC, SCOR, and IAPSO: The international thermodynamic equation of seawater – 2010: Calculation and use of thermodynamic properties, Intergovernmental Oceanographic Commission, Manuals and Guides, UNESCO, Paris, France, https://www.teos-10.org/pubs/TEOS-10_Manual.pdf (last access: 4 August 2023), 2010.
Jeffrey, S. W.: Profiles of photosynthetic pigments in the Ocean using thin-layer chromatography, Mar. Biol., 26, 101–110, https://doi.org/10.1007/BF00388879, 1974.
Jeffrey, S. W., Wright, S. W., and Zapata, M.: Recent advances in HPLC pigment analysis of phytoplankton, Mar. Freshwater Res., 50, 879–896, https://doi.org/10.1071/MF99109, 1999.
Koslow, J. A., Pesant, S., Feng, M., Pearce, A., Fearns, P., Moore, T., Matear, R., and Waite, A.: The effect of the Leeuwin current on phytoplankton biomass and production off southwestern Australia, J. Geophys. Res.-Oceans, 113, C07050, https://doi.org/10.1029/2007JC004102, 2008.
Lourey, M. J., Dunn, J. R., and Waring, J.: A mixed-layer nutrient climatology of Leeuwin current and Western Australian shelf waters: Seasonal nutrient dynamics and biomass, J. Marine Syst., 59, 25–51, https://doi.org/10.1016/j.jmarsys.2005.10.001, 2006.
Lourey, M. J., Thompson, P. A., McLaughlin, M. J., Bonham, P., and Feng, M.: Primary production and phytoplankton community structure during a winter shelf-scale phytoplankton bloom off Western Australia, Mar. Biol., 160, 355–369, https://doi.org/10.1007/s00227-012-2093-4, 2013.
Mantovanelli, A. and Thomson, P. G.: Particle backscattering coefficient for Wetlab Ecopucks in IMOS ANFOG gliders, IMOS Technical Report, https://doi.org/10.13130/RG.2.1.4875.5440, 2016.
Marañón, E., Van Wambeke, F., Uitz, J., Boss, E. S., Dimier, C., Dinasquet, J., Engel, A., Haëntjens, N., Pérez-Lorenzo, M., Taillandier, V., and Zäncker, B.: Deep maxima of phytoplankton biomass, primary production and bacterial production in the Mediterranean Sea, Biogeosciences, 18, 1749–1767, https://doi.org/10.5194/bg-18-1749-2021, 2021.
McCauley, R. D. and Cato, D. H.: Evening choruses in the Perth Canyon and their potential link with Myctophidae fishes, J. Acoust. Soc. Am., 140, 2384–2398, https://doi.org/10.1121/1.4964108, 2014.
McCauley, R., Bannister, J., Burton, C., Jenner, C., Rennie, S., and Salgado Kent, C.: Western Australian exercise area blue whale project. Final Report R2004-09, Centre for Marine Science and Technology, 73 pp., https://cmst.curtin.edu.au/wp-content/uploads/sites/4/2016/05/2004-29.pdf (last access: 13 February 2025), 2004.
McClain, C. R.: Satellite remote sensing: Ocean color, in: Encyclopedia of Ocean Sciences, edited by: Steele, J. H., Thorpe, S. A., and Turekian, K. K., Academic Press, San Diego, CA, United States, 114–126, ISBN: 978-0-12-227430-5, 2009.
McDougall, T. J. and Barker, P. M.: Getting started with TEOS-10 and the Gibbs Seawater (GSW) Oceanographic Toolbox version 3.06.12, SCOR/IAPSO, 1–28, https://www.teos-10.org/pubs/Getting_Started.pdf (last access: 4 August 2023), 2020.
Mignot, A., Claustre, H., Uitz, J., Poteau, A., D'Ortenzio, F., and Xing, X.: Understanding the seasonal dynamics of phytoplankton biomass and the deep chlorophyll maximum in oligotrophic environments: A bio-argo float investigation, Global Biogeochem. Cy., 28, 856–876, https://doi.org/10.1002/2013GB004781, 2014.
Morel, A. and Berthon, J. F.: Surface pigments, algal biomass profiles, and potential production of the euphotic layer: Relationships reinvestigated in view of remote-sensing applications, Limnol. Oceanogr., 34, 1545–1562, https://doi.org/10.4319/lo.1989.34.8.1545, 1989.
Morel, A. and Maritorena, S.: Bio-optical properties of oceanic waters: A reappraisal, J. Geophys. Res.-Oceans, 106, 7163–7180, https://doi.org/10.1029/2000jc000319, 2001.
Ocean Gliders Facility, Integrated Marine Observing System (IMOS): IMOS – Australian National Facility for Ocean Gliders (ANFOG) – delayed mode glider deployments, Australian Ocean Data Network, https://portal.aodn.org.au/ (last access: 13 February 2025), 2024.
Organelli, E., Barbieux, M., Claustre, H., Schmechtig, C., Poteau, A., Bricaud, A., Boss, E., Briggs, N., Dall'Olmo, G., D'Ortenzio, F., Leymarie, E., Mangin, A., Obolensky, G., Penkerc'h, C., Prieur, L., Roesler, C., Serra, R., Uitz, J., and Xing, X.: Two databases derived from BGC-Argo float measurements for marine biogeochemical and bio-optical applications, Earth Syst. Sci. Data, 9, 861–880, https://doi.org/10.5194/essd-9-861-2017, 2017.
Owen, K., Jenner, C. S., Jenner, M.-N. M., and Andrews, R. D.: A week in the life of a pygmy blue whale: Migratory dive depth overlaps with large vessel drafts, Anim. Biotelemetry, 4, 17, https://doi.org/10.1186/s40317-016-0109-4, 2016.
Palacios, D. M., Bailey, H., Becker, E. A., Bograd, S. J., DeAngelis, M. L., Forney, K. A., Hazen, E. L., Irvine, L. M., and Mate, B. R.: Ecological correlates of blue whale movement behavior and its predictability in the California Current Ecosystem during the summer-fall feeding season, Mov. Ecol., 7, 26, https://doi.org/10.1186/s40462-019-0164-6, 2019.
Parsons, T. T. and Strickland, J. D. H.: Discussion of spectrophotometric determination of marine-plant pigments, with revised equations for ascertaining chlorophylls and carotenoids, J. Mar. Res., 21, 155–163, 1963.
Paul, A. J., Coyle, K. O., and Ziemann, D. A.: Timing of spawning of Thysanoessa raschii (Euphausiacea) and occurrence of their feeding-stage larvae in an Alaskan Bay, J. Crustacean Biol., 10, 69–78, https://doi.org/10.1163/193724090X00258, 1990.
Pearce, A., Hart, A., Murphy, D., and Rice, H.: Seasonal wind patterns around the Western Australian coastline and their application in fisheries analysis, Fisheries Research Report No. 266, Department of Fisheries, 48 pp., https://www.fish.wa.gov.au/Documents/research_reports/frr266.pdf (last access: 13 February 2025), 2015.
Plourde, S., Winkler, G., Joly, P., St-Pierre, J. F., and Starr, M.: Long-term seasonal and interannual variations of krill spawning in the lower St Lawrence estuary, Canada, 1979–2009, J. Plankton Res., 33, 703–714, https://doi.org/10.1093/plankt/fbq144, 2011.
Quartly, G. D., Aiken, J., Brewin, R. J. W., and Yool, A.: The link between surface and sub-surface chlorophyll-a in the centre of the Antlantic subtropical gyres: A comparison of observations and models, Front. Mar. Sci., 10, 1197753, https://doi.org/10.3389/fmars.2023.1197753, 2023.
Quetin, L. B. and Ross, R. M.: Environmental variability and its impact on the reproductive cycle of Antarctic krill, Am. Zool., 41, 74–89, https://doi.org/10.1093/icb/41.1.74, 2001.
R Core Team: R: A language and environment for statistical computing, https://www.R-project.org/ (last access: 19 September 2023), 2022.
Rennie, S. J.: Oceanographic processes in the Perth Canyon and their impact on productivity, PhD, Curtin University of Technology, Perth, Western Australia, https://espace.curtin.edu.au/handle/20.500.11937/1904 (last access: 1 November 2024), 2005.
Rennie, S. J., McCauley, R. D., and Pattiaratchi, C. B.: Thermal structure above the Perth Canyon reveals Leeuwin Current, undercurrent and weather influences and the potential for upwelling, Mar. Freshwater Res., 57, 849–861, https://doi.org/10.1071/MF05247, 2006.
Rennie, S., Hanson, C. E., McCauley, R. D., Pattiaratchi, C., Burton, C., Bannister, J., Jenner, C., and Jenner, M. N.: Physical properties and processes in the Perth Canyon, Western Australia: Links to water column production and seasonal pygmy blue whale abundance, J. Marine Syst., 77, 21–44, https://doi.org/10.1016/j.jmarsys.2008.11.008, 2009a.
Rennie, S. J., Pattiaratchi, C. B., and McCauley, R. D.: Numerical simulation of the circulation within the Perth Submarine Canyon, Western Australia, Cont. Shelf. Res., 29, 2020–2036, https://doi.org/10.1016/j.csr.2009.04.010, 2009b.
Roesler, C. S. and Barnard, A. H.: Optical proxy for phytoplankton biomass in the absence of photophysiology: Rethinking the absorption line height, Methods in Oceanography, 7, 79–94, https://doi.org/10.1016/j.mio.2013.12.003, 2013.
Roesler, C., Uitz, J., Claustre, H., Boss, E., Xing, X., Organelli, E., Briggs, N., Bricaud, A., Schmechtig, C., Poteau, A., D'Ortenzio, F., Ras, J., Drapeau, S., Haëntjens, N., and Barbieux, M.: Recommendations for obtaining unbiased chlorophyll estimates from in situ chlorophyll fluorometers: A global analysis of WET Labs ECO sensors, Limnol. Oceanogr.-Meth., 15, 572–585, https://doi.org/10.1002/lom3.10185, 2017.
Salgado Kent, C., Bouchet, P., Wellard, R., Parnum, I., Fouda, L., and Erbe, C.: Seasonal productivity drives aggregations of killer whales and other cetaceans over submarine canyons of the Bremer Sub-Basin, south-western Australia, Aust. Mammal., 43, 168–178, https://doi.org/10.1071/AM19058, 2020.
Schmechtig, C., Claustre, H., Poteau, A., D'Ortenzio, F., Schallenberg, C., Trull, T. W., and Xing, X.: Biogeochemical-Argo quality control manual for chlorophyll-a concentration and chl-fluorescence, Version 3.0., https://doi.org/10.13155/35385, 2023.
Schmidt, K., Atkinson, A., Venables, H. J., and Pond, D. W.: Early spawning of Antarctic krill in the Scotia Sea is fuelled by “superfluous” feeding on non-ice associated phytoplankton blooms, Deep-Sea Res. Pt. II, 59–60, 159–172, https://doi.org/10.1016/j.dsr2.2011.05.002, 2012.
Scott, B. E., Sharples, J., Ross, O. N., Wang, J., Pierce, G. J., and Camphuysen, C. J.: Sub-surface hotspots in shallow seas: Fine-scale limited locations of top predator foraging habitat indicated by tidal mixing and sub-surface chlorophyll, Mar. Ecol. Prog. Ser., 408, 207–226, https://doi.org/10.3354/meps08552, 2010.
Seegers, B. N., Stumpf, R. P., Schaeffer, B. A., Loftin, K. A., and Werdell, P. J.: Performance metrics for the assessment of satellite data products: An ocean color case study, Opt. Express, 26, 7404, https://doi.org/10.1364/OE.26.007404, 2018.
Smith, R. C.: Remote sensing and depth distribution of ocean chlorophyll, Mar. Ecol. Prog. Ser., 5, 359–361, 1981.
Speakman, C. N., Hoskins, A. J., Hindell, M. A., Costa, D. P., Hartog, J. R., Hobday, A. J., and Arnould, J. P. Y.: Environmental influences on foraging effort, success and efficiency in female Australian fur seals, Sci. Rep.-UK, 10, 17710, https://doi.org/10.1038/s41598-020-73579-y, 2020.
Steele, J. H.: Environmental control of photosynthesis in the sea, Limnol. Oceanogr., 7, 137–150, https://doi.org/10.4319/lo.1962.7.2.0137, 1962.
Steele, J. H.: A study of production in the Gulf of Mexico, J. Mar. Res., 22, 211–222, 1964.
Steinke, K. B., Bernard, K. S., Ross, R. M., and Quetin, L. B.: Environmental drivers of the physiological condition of mature female Antarctic krill during the spawning season: implications for krill recruitment, Mar. Ecol. Prog. Ser., 669, 65–82, https://doi.org/10.3354/meps13720, 2021.
Suryan, R. M., Santora, J. A., and Sydeman, W. J.: New approach for using remotely sensed chlorophyll a to identify seabird hotspots, Mar. Ecol. Prog. Ser., 451, 213–225, https://doi.org/10.3354/meps09597, 2012.
Sutton, A. L.: Krill in the Leeuwin Current system: Influence of oceanography and contribution to Indian Ocean zoogeography, PhD, Murdoch University, Perth, Western Australia, https://researchportal.murdoch.edu.au/esploro/outputs/doctoral/Krill-in-the-Leeuwin-Current-system/991005544756707891 (last access: 13 September 2023), 2015.
Sutton, A. L. and Beckley, L. E.: Influence of the Leeuwin Current on the epipelagic euphausiid assemblages of the south-east Indian Ocean, Hydrobiologia, 779, 193–207, https://doi.org/10.1007/s10750-016-2814-7, 2016.
The MathWorks Inc.: MATLAB version: 9.13.0 (R2022b), https://www.mathworks.com/?s_tid=gn_logo (last access: 12 October 2023), 2022.
Thieurmel, B. and Elmarhraoui, A.: Suncalc: Compute sun position, sunlight phases, moon position, and lunar phase. R package version 0.5.1, https://CRA~N.R-project.org/package=suncalc (last access: 19 September 2023), 2022.
Thompson, P. A., Pesant, S., and Waite, A. M.: Contrasting the vertical differences in the phytoplankton biology of a dipole pair of eddies in the south-eastern Indian Ocean, Deep-Sea Res. Pt. II, 54, 1003–1028, https://doi.org/10.1016/j.dsr2.2006.12.009, 2007.
Thompson, P. A., Bonham, P., Waite, A. M., Clementson, L. A., Cherukuru, N., Hassler, C., and Doblin, M. A.: Contrasting oceanographic conditions and phytoplankton communities on the east and west coasts of Australia, Deep-Sea Res. Pt. II, 58, 645–663, https://doi.org/10.1016/j.dsr2.2010.10.003, 2011.
Thomson, P. G., Mantovanelli, A., Wright, S. W., and Pattiaratchi, C. B.: In situ comparisons of glider bio-optical measurements to CTD water properties, Presented at the 52nd Australian Marine Sciences Association Annual Conference: Estuaries to Oceans, Geelong, Victoria, Australia, 5–9 July 2015, https://www.amsa.asn.au/wp-content/uploads/2016/09/AMSA-2015-handbook.pdf (last access: 13 February 2025), 2015.
Thums, M., Ferreira, L. C., Jenner, C., Harris, D., Davenport, A., Andrews-Goff, V., Double, M., Möller, L., Attard, C. R. M., Bilgmann, K., Thomson, P. G., and McCauley, R.: Pygmy blue whale movement, distribution and important areas in the Eastern Indian Ocean, Global Ecol. Conserv., 35, e02054, https://doi.org/10.1016/j.gecco.2022.e02054, 2022.
Twomey, L. J., Waite, A. M., Pez, V., and Pattiaratchi, C. B.: Variability in nitrogen uptake and fixation in the oligotrophic waters off the south west coast of Australia, Deep-Sea Res. Pt. II, 54, 925–942, https://doi.org/10.1016/j.dsr2.2006.10.001, 2007.
Uitz, J., Claustre, H., Morel, A., and Hooker, S. B.: Vertical distribution of phytoplankton communities in open ocean: An assessment based on surface chlorophyll, J. Geophys. Res.-Oceans, 111, C08005, https://doi.org/10.1029/2005JC003207, 2006.
van Ruth, P., Rodriguez, A. R., Davies, C., and Richardson, A. J.: Indicators of depth layers important to phytoplankton production, State and Trends of Australia's Ocean Report, https://doi.org/10.26198/5e16a98549e7d, 2020.
Visser, F., Hartman, K. L., Pierce, G. J., Valavanis, V. D., and Huisman, J.: Timing of migratory baleen whales at the Azores in relation to the North Atlantic spring bloom, Mar. Ecol. Prog. Ser., 440, 267–279, https://doi.org/10.3354/meps09349, 2011.
Waite, A. M., Thompson, P. A., Feng, M., Beckley, L. E., Domingues, C. M., Gaughan, D., Hanson, C. E., Holl, C. M., Koslow, T., Meuleners, M., Montova, J. P., Moore, T., Muhling, B. A., Paterson, H., Rennie, S., Strzelecki, J., and Twomey, L.: The Leeuwin Current and its eddies: An introductory overview, Deep-Sea Res. Pt. II, 54, 789–796, https://doi.org/10.1016/j.dsr2.2006.12.008, 2007.
Weston, K., Fernand, L., Mills, D. K., Delahunty, R., and Brown, J.: Primary production in the deep chlorophyll maximum of the central North Sea, J. Plankton Res., 27, 909–922, https://doi.org/10.1093/plankt/fbi064, 2005.
Whiteway, T.: Australian bathymetry and topography grid, June 2009. Scale 1:5 000 000, https://doi.org/10.4225/25/53D99B6581B9A, 2009.
Woo, L. M. and Gourcuff, C.: Delayed mode QA/QC best practice manual version 3.1, Integrated Marine Observing System (IMOS), 1–60, https://doi.org/10.26198/5c997b5fdc9bd, 2023.
Woo, M. and Pattiaratchi, C.: Hydrography and water masses off the western Australian coast, Deep-Sea Res. Pt. I, 55, 1090–1104, https://doi.org/10.1016/j.dsr.2008.05.005, 2008.
Wu, J., Lee, Z., Xie, Y., Goes, J., Shang, S., Marra, J. F., Lin, G., Yang, L., and Huang, B.: Reconciling between optical and biological determinants of the euphotic zone depth, J. Geophys. Res.-Oceans, 126, e2020JC016874, https://doi.org/10.1029/2020JC016874, 2021.
Yentsch, C. S. and Menzel, D. W.: A method for the determination of phytoplankton chlorophyll and phaeophytin by fluorescence, Deep Sea Research and Oceanographic Abstracts, 10, 221–231, https://doi.org/10.1016/0011-7471(63)90358-9, 1963.
Yoshida, T., Virtue, P., Kawaguchi, S., and Nichols, P. D.: Factors determining the hatching success of Antarctic krill Euphausia superba embryo: Lipid and fatty acid composition, Mar. Biol., 158, 2313–2325, https://doi.org/10.1007/s00227-011-1735-2, 2011.
Short summary
Marine habitat models do not include deep chlorophyll maxima, which may support higher trophic level foraging in (meso-)oligotrophic habitats. We used ocean glider data to show that chlorophyll maxima form off Western Australia in September–April. At least 50 % were biomass maxima, likely supporting local krill growing sufficiently for whale consumption. We suggest including deep chlorophyll maxima in marine habitat models as deep depth-integrated estimates from satellite-derived surface values.
Marine habitat models do not include deep chlorophyll maxima, which may support higher trophic...
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