Seaweed Week! With Maine Sea Grant and MITA Jaclyn Robidoux, Marine Extension Associate Maine Sea Grant and University of Maine Cooperative Extension Seaweed Algae Macroalgae Microalgae Sea Vegetables Ew Collection: J. Morill, 1975 A L G A E M I C R O A L G A E M A C R O A L G A E ( S E A W E E D ) Microscopic/single celled Macroscopic/multi-cellular Freshwater and marine species Marine species Form base of aquatic food webs Provide habitat and food (“sea vegetables”) Maine’s coast is home to over 200 species of seaweed, that provide essential primary production, nutrient cycling, habitat, and food to healthy coastal ecosystems. Seaweeds also play a role in Maine’s marine resource economy and working waterfront heritage, as a regulated fisheries and aquaculture product. A L G A L C L A S S I F I C A T I O N R E D S B R O W N S G R E E N S Dulse (Palmaria) Sugar Kelp (Saccharina) Sea Lettuce (Ulva) Irish Moss (Chondrus) Winged Kelp (Alaria) Microalgae Nori/Laver (Porphyra, etc.) Rockweed (Ascophyllum) Ecological role of seaweeds Sunlight Oxygen Structure and Habitat CO2 Marine Living Biomass Food Webs Nutrients Human Resource Collection: V. Krishnamurthy, 1964 S E A W E E D V S P L A N T S Seaweeds are the the precursors to land plants and serve similar ecological roles in the marine environment: Habitat and structure Primary production Photosynthesize However, seaweeds are fundamentally different than land plants because they lack true plant structures: Roots Leafy shoots Flowers Vascular tissues Ok but they have to be pretty closely related? Nope! Current evolutionary “tree of life” based on molecular DNA Seaweeds are polyphyletic – they belong to multiple kingdoms within on the tree of life! Algae (3rd Edition). Graham et al., 2016 S T R U C T U R E RECEPTACLE BLADE AIR BLADDER THALLUS = ENTIRE BODY STIPE Collector: Holden, 1901 Collector: A. Sutherland, 1970 HOLDFAST G R O W T H 1) APICAL MERISTEM Meristem: Region of active cell division and growth 3) MARGINAL 4) DIFFUSE 2) INTERCALARY MERISTEM Collector: Holden, 1901 Collector: A. Sutherland, 1970 Z O N A T I O N Species-specific zonation exists within the intertidal and subtidal zones. Generally: Brown > Green > Red > Subtidal Brown R E P R O D U C T I O N Seaweeds have complex life histories… K E L P NE Seaweed Culture Handbook Sporophyte: two sets of chromosomes (like us) Gametophyte: only one set of chromosomes R E P R O D U C T I O N Seaweeds have complex life histories… N O R I (sporophyte) NE Seaweed Culture Handbook Sporophyte: two sets of chromosomes (like us) Gametophyte: only one set of chromosomes Maine Sea Farms, Bristol ME Bangs Island Kelp/Wild Ocean Aquaculture, Portland ME M A I N E S S E A W E E D I N D U S T R I E S W I L D H A R V E S T A Q U A C U L T U R E For over 50 years, Maine’s wild In 2010, commercial seaweed harvest seaweed fishery has aquaculture of sugar kelp commercially harvested Rockweed began in Maine and has been and sea vegetables. growing and expanding since. High protein and fiber content H E A L T H Unique vitamins not found in land plants (B12) Nutrients and bioactive compounds (antioxidants) B E N E F I T S Anti-viral, anti-fungal, anti-cancer properties High in iodine E D I B L E S E A W E E D S The Maine Ten: The Maine Ten is a list of ten commercially important edible seaweed species in the Gulf of Maine R O C K W E E D ASCOPHYLLUM NODOSUM • Large brown algae • Intertidal • Air bladders and receptacles (seasonal) • Use to steam lobster and clams in traditional clambakes B L A D D E R W R A C K FUCUS VESICULOSUS • Medium sized brown algae • Intertidal • Gel-filled tips at the end of the blade • Mid-rib that runs through center • Steam with shellfish or blanch fresh tips to top salads, pizza, etc. S U G A R K E L P SACCHARINA LATISSIMA • Large brown algae • Subtidal • Single large blade with a stipe and holdfast • Use in place of spinach! Make your own seaweed salad, smoothie cubes, etc. • Large brown algae • Golden color • Subtidal • Cold areas with high wave action • Mid-rib runs through center W I N G E D K E L P • “Atlantic Wakame” – delicate ALARIA ESCULENTA flavor is great for salads • Large brown algae • Subtidal • Rare in the wild – high wave energy environments • Farmed throughout Maine • Similar uses to sugar kelp – a little more delicate S K I N N Y K E L P SACCHARINA ANGUSTISSIMA • Large brown algae • Subtidal, high wave energy environments • Broad blade splits into ribbons • Similar to Japanese “Kombu” – thick blade is great in soup stocks and adding flavor to dishes H O R S E T A I L K E L P LAMINARIA DIGITATA D U L S E PALMERIA PALMATA • Medium sized red algae • Dark red to purplish color • Low intertidal to subtidal • Blade is shaped like a hand • Great dried and eaten as a snack or sprinkled on cheese, eggs, rice bowls, etc. • Small red algae • Intertidal and subtidal • Bushy and iridescent • Grows in carpets • Source of carrageenan • Thicken foods, puddings, beverages I R I S H M O S S CHONDRUS CRISPUS N O R I / L A V E R PORPHYRA SPP., WILDEMANIA SPP., ETC. • Small/medium red algae • Golden, light pink, deep red or purple • Intertidal and subtidal • Very thin - 1-2 cell layers thick! Feels slippery but is tough • Savory flavor is great in stir fries, with eggs, veggies, meats, and potatoes • Small/medium green algae • Intertidal and subtidal S E A L E T T U C E • Common ULVA SPP. • Flat or wavy blades • Strong ocean flavor pairs well with lemon to make seaweed lemon butter. A little goes a long way • Use common sense - safe, clean sites • Be aware of pertinent state regulations C O L L E C T I N G • Allow seaweeds to regenerate – don’t pull up the holdfast T I P S • Pressing and art: use seaweeds that have washed up or are floating • Take only what you need • Need: thick paper, wax paper • Just like pressing flowers and plants P R E S S I N G • Some seaweeds press better than others • Get creative! Blades are nice but T I P S unassuming seaweeds can be beautiful when pressed • Minimize moisture R E S O U R C E S Maine Sea Grant. Resources for Seaweed Growers https://seagrant.umaine.edu/extension/resources-for-seaweed-growers/ Maine Seaweed Council. Harvester’s Field Guide to Maine Seaweeds: https://www.seaweedcouncil.org/wp-content/uploads/MSC-Field-Guide-Aug-2014-FINAL-reformatted-new-url.pdf New Hampshire Sea Grant. Field Guide: Common Seaweeds on NH Shores https://extension.unh.edu/resource/field-guide-common-seaweeds-new-hampshire-shores.