Phylum Arthropoda Phylum Mollusca Other Phyla

Total Page:16

File Type:pdf, Size:1020Kb

Phylum Arthropoda Phylum Mollusca Other Phyla Phylum Arthropoda Phylum Mollusca Other Phyla Acorn Barnacle Balanus glandulus Yellow-Green Encrusting Sponge Blue Mussel Mytilus trossulus ~ 6 smooth plated sides Halichondria panicea Phylum Porifera ~ smooth shell with growth lines ~ diameter usually less than 1.5 cm ~ simplest multi-cellular organism ~ attaches to rocks with byssal threads ~ stays moist by staying closed ~ no organs; body acts as a filter for ~ a favorite food of sea stars feeding ~ opens up and feeds when under water Calcareous Tube Worm Thatched Barnacle Semibalanus cariosus Seaslug Nudibranch Phylum Annelida ~ 6 wall plates composed of vertical ~ Latin: nudus, naked + brankhia, gills ~ tubes formed from calcium tube-like ribs giving a thatched look ~ breaths through feathery gills carbonate found in sea water ~ eats by kicking food into its mouth ~ sheds its shell after its larval stage ~ crown serves the dual purpose of ~ lives up to 15 years respiration and filter feeding Black Katy Chiton Katharina tunicata Beach Hopper Traskorchestia traskiana ~ has 8 shell plates Clam Worm Nereis vexillosa ~ sometimes called sand fleas ~ butterfly-shaped plates are often left Phylum Annelida ~ length less than 1.8 cm by birds in the woods ~ can grow to 30 cm ~ has 14 legs and looks like a shrimp ~ a food source for native Alaskans ~ secretes an acid that it uses to ~ found at high tide line under algae burrow through clam shells Isopod Idotea spp. Shield Limpet Collisella pelta ~ important food source for birds ~ various species ~ snail with a cone-shaped shell Gunnels and Pricklebacks ~ 1.5 cm, flattened body ~ uses a muscular foot to attach to rocks Phylum Chordata ~ lives under rocks ~ rasps food from rocks with file-like ~ many members of these two ~ scavenger tongue called a radula families look similar ~ lives under rocks Hermit Crab Pagurus spp. Sitka Periwinkle Littorina sitkana ~ 28 Species in Alaska ~ round spiral shell, up to 1.5 cm long Tide Pool Sculpin Oligocottus maculosus ~ lives in a snail shell for protection ~ most are brown or gray Phylum Chordata ~ fight among selves for food and shells ~ some have lighter bands ~ big head and tapering body ~ large pectoral fins ~ not true crabs Snails and Welks ~ can change color to blend in Graceful Kelp Crab Pugettia gracilis ~ protected by a hard calcium shell Sea Anemone ~ carapace resembles a sheriff’s badge ~ has plume-like gills and eyes on tentacles Phylum Cnidaria ~ length about 5 cm ~ has a single muscular foot with a cover called an operculum ~ cylindrical shape with an oral disk at the top ~ found living on and eating kelp which protects it from predators and water loss ~ tentacles have stinging cells called nematocysts ~ often attaches kelp to carapace ~ tentacles fold in to capture prey Pygmy Rock Crab Cancer oregonensis ~ heavy-looking, claws have black tips Frilled File ~ adults are reddish brown Hairy Triton Dire Welk ~ legs covered with small hairs ` Dogwinkle Dogwinkle Fusitriton Nucella Lirabuccinum ~ up to 5 cm wide Nucella lima oregonensis lamellosa dirum Christmas Burrowing Rose Urticina crassicornis Anthopleura artemisia Urticina piscivora Marine Algae Phylum Echinodermata Sea Lettuce Ulva spp. Green Sea Urchin Stronglocentrotus droebachiensis ~ at least 11 different species Fort Abercrombie State Historical Park ~ thin, transparent blade consisting of ~ can be red, purple, green or white two cell layers ~ has 5 teeth operated by a jaw structure called an Aristotle’s lantern ~ edible Guide to Marine Life Sea Star Black Pine Algae Neorhodomela larix ~ Class Asteroidea ~ color is brownish-black to black ~ has a water vascular system ~ looks like “dreadlocks” that operates its tube feet ~ often has Sea Cauliflower attached Common Star Rainbow Star Pisaster ochraceus ~ can regenerate lost limbs Orthasterias koehleri Sea Sac Halosaccion glandiforme ~ sometimes called “deadman’s fingers” ~ water-filled sacs make good squirt guns when gently squeezed Blood Star Six-Rayed Star Sunflower Star Mottled Star Henricia leviuscula Leptasterias hexactis Pycnopodia helianthoides Evasterias troschelii Crustose Corallines Clathromorphum, Lithothamnion, Melobesia, and Mesophyllum Intertidal Zone The intertidal zone is the area between the ~ exact species hard to identify highest high tide and the lowest low tide of the year. It is broken up into zones based upon vertical height and tide ~ calcium carbonate in cell walls ~ contain chlorophyll coverage. Intertidal animals are adapted to life in specific ~ are photosynthetic zones. Zone One The splash zone of life extends from the highest splash of Sea Cauliflower Leathesia marina ocean spray and storm waves to the average of all high tides. Most of ~ thick, convoluted outer layer these organisms are land dwellers that can withstand exposure to - ~ very slimy when torn salt water and air that can dry them out. ~ often attaches to Black Pine Algae Zone Two The high intertidal zone extends from the average high tide mark to mean sea level. Most of the animals of Zone Two are Rock Weed or Pop Weed Fucus distichus accustomed to tolerating air exposure. ~ can reach lengths of 25 cm Zone Three This zone is below mean sea level. It is uncovered by ~ fronds have air bladders on tips that most low tides and covered by most high tides. There are a variety contain reproductive structures of different habitats in this zone. ~ provides shelter for other organisms Zone Four This zone is only uncovered during minus tides. Only a few animals are exposed to wave action, sun and wind. This zone Bull Kelp Nereocysitis luetkeana has the greatest diversity of intertidal life. ~ holdfast attaches alga to ocean floor ~ stalk ends in round bulb-shaped float Images and documentation compiled for ~ bulb has flat blades attached Fort Abercrombie State Historical Park by volunteers, Nancy & Melissa Meitle, Summer 2011. ~ bulb used for containers by native This document is available at http://dnr.alaska.gov/parks/units/kodiak/ftaber.htm Alaskans .
Recommended publications
  • Diversity and Community Structure of Pelagic Cnidarians in the Celebes and Sulu Seas, Southeast Asian Tropical Marginal Seas
    Deep-Sea Research I 100 (2015) 54–63 Contents lists available at ScienceDirect Deep-Sea Research I journal homepage: www.elsevier.com/locate/dsri Diversity and community structure of pelagic cnidarians in the Celebes and Sulu Seas, southeast Asian tropical marginal seas Mary M. Grossmann a,n, Jun Nishikawa b, Dhugal J. Lindsay c a Okinawa Institute of Science and Technology Graduate University (OIST), Tancha 1919-1, Onna-son, Okinawa 904-0495, Japan b Tokai University, 3-20-1, Orido, Shimizu, Shizuoka 424-8610, Japan c Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Yokosuka 237-0061, Japan article info abstract Article history: The Sulu Sea is a semi-isolated, marginal basin surrounded by high sills that greatly reduce water inflow Received 13 September 2014 at mesopelagic depths. For this reason, the entire water column below 400 m is stable and homogeneous Received in revised form with respect to salinity (ca. 34.00) and temperature (ca. 10 1C). The neighbouring Celebes Sea is more 19 January 2015 open, and highly influenced by Pacific waters at comparable depths. The abundance, diversity, and Accepted 1 February 2015 community structure of pelagic cnidarians was investigated in both seas in February 2000. Cnidarian Available online 19 February 2015 abundance was similar in both sampling locations, but species diversity was lower in the Sulu Sea, Keywords: especially at mesopelagic depths. At the surface, the cnidarian community was similar in both Tropical marginal seas, but, at depth, community structure was dependent first on sampling location Marginal sea and then on depth within each Sea. Cnidarians showed different patterns of dominance at the two Sill sampling locations, with Sulu Sea communities often dominated by species that are rare elsewhere in Pelagic cnidarians fi Community structure the Indo-Paci c.
    [Show full text]
  • MARINE TANK GUIDE About the Marine Tank
    HOME EDITION MARINE TANK GUIDE About the Marine Tank With almost 34,000 miles of coastline, Alaska’s intertidal zones, the shore areas exposed and covered by ocean tides, are home to a variety of plants and animals. The Anchorage Museum’s marine tank is home to Alaskan animals which live in the intertidal zone. The plants and animals in the Museum’s marine tank are collected under an Alaska Department of Fish and Game Aquatic Resource Permit during low tide at various beaches in Southcentral and Southeast Alaska. Visitors are asked not to touch the marine animals. Touching is stressful for the animals. A full- time animal care technician maintains the marine tank. Since the tank is not located next to the ocean, ocean water cannot be constantly pumped through it. This means special salt water is mixed at the Museum. The tank is also cleaned regularly. Equipment which keeps the water moving, clean, chilled to 43°F and constantly monitored. Contamination from human hands would impact the cleanliness of the water and potentially hurt the animals. A second tank is home to the Museum’s king crab, named King Louie, and black rockfish, named Sebastian. King crab and black rockfish of Alaska live in deeper waters than the intertidal zone creatures. This guide shares information about some of the Museum’s marine animals. When known, the Dena’ina word for an animal is included, recognizing the thousands of years of stewardship and knowledge of Indigeneous people of the Anchorage area and their language. The Dena’ina & Marine Species The geographically diverse Dena’ina lands span both inland and coastal areas, including Anchorage.
    [Show full text]
  • Black Oystercatcher Diet and Provisioning 2014 Annual Report
    National Park Service U.S. Department of the Interior Natural Resource Stewardship and Science Black Oystercatcher Chick Diet and Provisioning 2014 Annual Report Natural Resource Data Series NPS/KEFJ/NRDS—2015/749 ON THIS PAGE Nest camera captures a black oystercatcher provisioning chick on Natoa Island. Photograph Courtesy: NPS/Kenai Fjords National Park ON THE COVER Black oystercatchers at nest in Aialik Bay, Kenai Fjords National Park Photograph by: NPS/Katie Thoresen Black Oystercatcher Diet and Provisioning 2014 Annual Report Natural Resource Data Series NPS/KEFJ/NRDS—2015/749 Sam Stark1, Brian Robinson2 and Laura M. Phillips1 1National Park Service Kenai Fjords National Park PO Box 1727 Seward, AK 99664 2 University of Alaska, Fairbanks Department of Biology and Wildlife PO Box 756100 Fairbanks, AK 99775 January 2015 U.S. Department of the Interior National Park Service Natural Resource Stewardship and Science Fort Collins, Colorado The National Park Service, Natural Resource Stewardship and Science office in Fort Collins, Colorado, publishes a range of reports that address natural resource topics. These reports are of interest and applicability to a broad audience in the National Park Service and others in natural resource management, including scientists, conservation and environmental constituencies, and the public. The Natural Resource Data Series is intended for the timely release of basic data sets and data summaries. Care has been taken to assure accuracy of raw data values, but a thorough analysis and interpretation of the data has not been completed. Consequently, the initial analyses of data in this report are provisional and subject to change. All manuscripts in the series receive the appropriate level of peer review to ensure that the information is scientifically credible, technically accurate, appropriately written for the intended audience, and designed and published in a professional manner.
    [Show full text]
  • Testing the Generality of the Trophic Cascade Paradigm for Sea Otters: a Case Study with Kelp Forests in Northern Washington, USA
    Hydrobiologia (2007) 579:233–249 DOI 10.1007/s10750-006-0403-x PRIMARY RESEARCH PAPER Testing the generality of the trophic cascade paradigm for sea otters: a case study with kelp forests in northern Washington, USA Sarah K. Carter Æ Glenn R. VanBlaricom Æ Brian L. Allen Received: 6 April 2006 / Revised: 24 August 2006 / Accepted: 15 September 2006 / Published online: 31 January 2007 Ó Springer Science+Business Media B.V. 2007 Abstract Trophic cascade hypotheses for biolog- followed by a decline in diversity as one or a few ical communities, linking predation by upper tro- perennial algal species become dominant. Both sea phic levels to major features of ecological structure otter predation and commercial sea urchin harvest and dynamics at lower trophic levels, are widely are ecologically and economically important subscribed and may influence conservation policy. sources of urchin mortality in nearshore benthic Few such hypotheses have been evaluated for systems in northern Washington marine waters. We temporal or spatial generality. Previous studies of recorded changes in density of macroalgae in San sea otter (Enhydra lutris) predation along the outer Juan Channel, a marine reserve in the physically coast of North America suggest a pattern, often protected inland waters of northern Washington, elevated to the status of paradigm, in which sea otter resulting from three levels of experimental urchin presence leads to reduced sea urchin (Strongylo- harvest: (1) simulated sea otter predation (monthly centrotus spp.) biomass and rapid increases in complete harvest of sea urchins), (2) simulated abundance and diversity of annual algal species, commercial urchin harvest (annual size-selective harvest of sea urchins), and (3) no harvest (control).
    [Show full text]
  • Marine Invertebrate Field Guide
    Marine Invertebrate Field Guide Contents ANEMONES ....................................................................................................................................................................................... 2 AGGREGATING ANEMONE (ANTHOPLEURA ELEGANTISSIMA) ............................................................................................................................... 2 BROODING ANEMONE (EPIACTIS PROLIFERA) ................................................................................................................................................... 2 CHRISTMAS ANEMONE (URTICINA CRASSICORNIS) ............................................................................................................................................ 3 PLUMOSE ANEMONE (METRIDIUM SENILE) ..................................................................................................................................................... 3 BARNACLES ....................................................................................................................................................................................... 4 ACORN BARNACLE (BALANUS GLANDULA) ....................................................................................................................................................... 4 HAYSTACK BARNACLE (SEMIBALANUS CARIOSUS) .............................................................................................................................................. 4 CHITONS ...........................................................................................................................................................................................
    [Show full text]
  • THE CASE AGAINST Marine Mammals in Captivity Authors: Naomi A
    s l a m m a y t T i M S N v I i A e G t A n i p E S r a A C a C E H n T M i THE CASE AGAINST Marine Mammals in Captivity The Humane Society of the United State s/ World Society for the Protection of Animals 2009 1 1 1 2 0 A M , n o t s o g B r o . 1 a 0 s 2 u - e a t i p s u S w , t e e r t S h t u o S 9 8 THE CASE AGAINST Marine Mammals in Captivity Authors: Naomi A. Rose, E.C.M. Parsons, and Richard Farinato, 4th edition Editors: Naomi A. Rose and Debra Firmani, 4th edition ©2009 The Humane Society of the United States and the World Society for the Protection of Animals. All rights reserved. ©2008 The HSUS. All rights reserved. Printed on recycled paper, acid free and elemental chlorine free, with soy-based ink. Cover: ©iStockphoto.com/Ying Ying Wong Overview n the debate over marine mammals in captivity, the of the natural environment. The truth is that marine mammals have evolved physically and behaviorally to survive these rigors. public display industry maintains that marine mammal For example, nearly every kind of marine mammal, from sea lion Iexhibits serve a valuable conservation function, people to dolphin, travels large distances daily in a search for food. In learn important information from seeing live animals, and captivity, natural feeding and foraging patterns are completely lost.
    [Show full text]
  • California Coast Educator Guide
    California Coast Educator Guide Preschool –Grade 2 What’s Inside: A. Exhibit Overview B. Exhibit Map c. Key Concepts d. Vocabulary E. museum connections f. Resources A. exhibit overview The mix of sunshine, wind, water and geology has created one of the world’s richest temperate marine communities. Come see why it’s special and protected. Welcome to the Northern California Coast, home to some of the world’s Use this guide to: richest temperate marine ecosystems. In this exhibit, students can learn » Plan your field trip to about the coastal ecosystems of the Northern California Coast on both the California Academy of Sciences’ Northern Level 1 and the Lower Level. California Coast exhibit. Upstairs on Level 1, students can follow a walkway along a transect of » Learn about exhibit themes, key concepts the coast from the San Francisco Bay estuary to the rocky coastline. and behind–the–scenes Downstairs on the Lower Level, students will have several underwater information to enhance views into the rocky coast tank, modeled on the habitats of the Gulf of and guide your students’ experience. the Farallones National Marine Sanctuary, including a dramatic floor–to– » Link to exhibit–related ceiling window. Students will walk through a gallery of medium–size and activities you can smaller tanks displaying characteristic habitats of the California coast, download. including rocky coast, rocky reef and sandy bottom. » Connect your field trip to the classroom. Through interactive stations, students can learn more about the Gulf of the Farallones National Marine Sanctuary and California marine life. Students can also interact with docents and use magnifiers to explore a variety of marine organisms at the Tidepool.
    [Show full text]
  • Download Download
    Appendix C: An Analysis of Three Shellfish Assemblages from Tsʼishaa, Site DfSi-16 (204T), Benson Island, Pacific Rim National Park Reserve of Canada by Ian D. Sumpter Cultural Resource Services, Western Canada Service Centre, Parks Canada Agency, Victoria, B.C. Introduction column sampling, plus a second shell data collect- ing method, hand-collection/screen sampling, were This report describes and analyzes marine shellfish used to recover seven shellfish data sets for investi- recovered from three archaeological excavation gating the siteʼs invertebrate materials. The analysis units at the Tseshaht village of Tsʼishaa (DfSi-16). reported here focuses on three column assemblages The mollusc materials were collected from two collected by the researcher during the 1999 (Unit different areas investigated in 1999 and 2001. The S14–16/W25–27) and 2001 (Units S56–57/W50– source areas are located within the village proper 52, S62–64/W62–64) excavations only. and on an elevated landform positioned behind the village. The two areas contain stratified cultural Procedures and Methods of Quantification and deposits dating to the late and middle Holocene Identification periods, respectively. With an emphasis on mollusc species identifica- The primary purpose of collecting and examining tion and quantification, this preliminary analysis the Tsʼishaa shellfish remains was to sample, iden- examines discarded shellfood remains that were tify, and quantify the marine invertebrate species collected and processed by the site occupants for each major stratigraphic layer. Sets of quantita- for approximately 5,000 years. The data, when tive information were compiled through out the reviewed together with the recovered vertebrate analysis in order to accomplish these objectives.
    [Show full text]
  • DEEP SEA LEBANON RESULTS of the 2016 EXPEDITION EXPLORING SUBMARINE CANYONS Towards Deep-Sea Conservation in Lebanon Project
    DEEP SEA LEBANON RESULTS OF THE 2016 EXPEDITION EXPLORING SUBMARINE CANYONS Towards Deep-Sea Conservation in Lebanon Project March 2018 DEEP SEA LEBANON RESULTS OF THE 2016 EXPEDITION EXPLORING SUBMARINE CANYONS Towards Deep-Sea Conservation in Lebanon Project Citation: Aguilar, R., García, S., Perry, A.L., Alvarez, H., Blanco, J., Bitar, G. 2018. 2016 Deep-sea Lebanon Expedition: Exploring Submarine Canyons. Oceana, Madrid. 94 p. DOI: 10.31230/osf.io/34cb9 Based on an official request from Lebanon’s Ministry of Environment back in 2013, Oceana has planned and carried out an expedition to survey Lebanese deep-sea canyons and escarpments. Cover: Cerianthus membranaceus © OCEANA All photos are © OCEANA Index 06 Introduction 11 Methods 16 Results 44 Areas 12 Rov surveys 16 Habitat types 44 Tarablus/Batroun 14 Infaunal surveys 16 Coralligenous habitat 44 Jounieh 14 Oceanographic and rhodolith/maërl 45 St. George beds measurements 46 Beirut 19 Sandy bottoms 15 Data analyses 46 Sayniq 15 Collaborations 20 Sandy-muddy bottoms 20 Rocky bottoms 22 Canyon heads 22 Bathyal muds 24 Species 27 Fishes 29 Crustaceans 30 Echinoderms 31 Cnidarians 36 Sponges 38 Molluscs 40 Bryozoans 40 Brachiopods 42 Tunicates 42 Annelids 42 Foraminifera 42 Algae | Deep sea Lebanon OCEANA 47 Human 50 Discussion and 68 Annex 1 85 Annex 2 impacts conclusions 68 Table A1. List of 85 Methodology for 47 Marine litter 51 Main expedition species identified assesing relative 49 Fisheries findings 84 Table A2. List conservation interest of 49 Other observations 52 Key community of threatened types and their species identified survey areas ecological importanc 84 Figure A1.
    [Show full text]
  • Comparative Neuroanatomy of Mollusks and Nemerteans in the Context of Deep Metazoan Phylogeny
    Comparative Neuroanatomy of Mollusks and Nemerteans in the Context of Deep Metazoan Phylogeny Von der Fakultät für Mathematik, Informatik und Naturwissenschaften der RWTH Aachen University zur Erlangung des akademischen Grades einer Doktorin der Naturwissenschaften genehmigte Dissertation vorgelegt von Diplom-Biologin Simone Faller aus Frankfurt am Main Berichter: Privatdozent Dr. Rudolf Loesel Universitätsprofessor Dr. Peter Bräunig Tag der mündlichen Prüfung: 09. März 2012 Diese Dissertation ist auf den Internetseiten der Hochschulbibliothek online verfügbar. Contents 1 General Introduction 1 Deep Metazoan Phylogeny 1 Neurophylogeny 2 Mollusca 5 Nemertea 6 Aim of the thesis 7 2 Neuroanatomy of Minor Mollusca 9 Introduction 9 Material and Methods 10 Results 12 Caudofoveata 12 Scutopus ventrolineatus 12 Falcidens crossotus 16 Solenogastres 16 Dorymenia sarsii 16 Polyplacophora 20 Lepidochitona cinerea 20 Acanthochitona crinita 20 Scaphopoda 22 Antalis entalis 22 Entalina quinquangularis 24 Discussion 25 Structure of the brain and nerve cords 25 Caudofoveata 25 Solenogastres 26 Polyplacophora 27 Scaphopoda 27 i CONTENTS Evolutionary considerations 28 Relationship among non-conchiferan molluscan taxa 28 Position of the Scaphopoda within Conchifera 29 Position of Mollusca within Protostomia 30 3 Neuroanatomy of Nemertea 33 Introduction 33 Material and Methods 34 Results 35 Brain 35 Cerebral organ 38 Nerve cords and peripheral nervous system 38 Discussion 38 Peripheral nervous system 40 Central nervous system 40 In search for the urbilaterian brain 42 4 General Discussion 45 Evolution of higher brain centers 46 Neuroanatomical glossary and data matrix – Essential steps toward a cladistic analysis of neuroanatomical data 49 5 Summary 53 6 Zusammenfassung 57 7 References 61 Danksagung 75 Lebenslauf 79 ii iii 1 General Introduction Deep Metazoan Phylogeny The concept of phylogeny follows directly from the theory of evolution as published by Charles Darwin in The origin of species (1859).
    [Show full text]
  • Temporal Trends of Two Spider Crabs (Brachyura, Majoidea) in Nearshore Kelp Habitats in Alaska, U.S.A
    TEMPORAL TRENDS OF TWO SPIDER CRABS (BRACHYURA, MAJOIDEA) IN NEARSHORE KELP HABITATS IN ALASKA, U.S.A. BY BENJAMIN DALY1,3) and BRENDA KONAR2,4) 1) University of Alaska Fairbanks, School of Fisheries and Ocean Sciences, 201 Railway Ave, Seward, Alaska 99664, U.S.A. 2) University of Alaska Fairbanks, School of Fisheries and Ocean Sciences, P.O. Box 757220, Fairbanks, Alaska 99775, U.S.A. ABSTRACT Pugettia gracilis and Oregonia gracilis are among the most abundant crab species in Alaskan kelp beds and were surveyed in two different kelp habitats in Kachemak Bay, Alaska, U.S.A., from June 2005 to September 2006, in order to better understand their temporal distribution. Habitats included kelp beds with understory species only and kelp beds with both understory and canopy species, which were surveyed monthly using SCUBA to quantify crab abundance and kelp density. Substrate complexity (rugosity and dominant substrate size) was assessed for each site at the beginning of the study. Pugettia gracilis abundance was highest in late summer and in habitats containing canopy kelp species, while O. gracilis had highest abundance in understory habitats in late summer. Large- scale migrations are likely not the cause of seasonal variation in abundances. Microhabitat resource utilization may account for any differences in temporal variation between P. gracilis and O. gracilis. Pugettia gracilis may rely more heavily on structural complexity from algal cover for refuge with abundances correlating with seasonal changes in kelp structure. Oregonia gracilis mayrelyonkelp more for decoration and less for protection provided by complex structure. Kelp associated crab species have seasonal variation in habitat use that may be correlated with kelp density.
    [Show full text]
  • The Biology of Seashores - Image Bank Guide All Images and Text ©2006 Biomedia ASSOCIATES
    The Biology of Seashores - Image Bank Guide All Images And Text ©2006 BioMEDIA ASSOCIATES Shore Types Low tide, sandy beach, clam diggers. Knowing the Low tide, rocky shore, sandstone shelves ,The time and extent of low tides is important for people amount of beach exposed at low tide depends both on who collect intertidal organisms for food. the level the tide will reach, and on the gradient of the beach. Low tide, Salt Point, CA, mixed sandstone and hard Low tide, granite boulders, The geology of intertidal rock boulders. A rocky beach at low tide. Rocks in the areas varies widely. Here, vertical faces of exposure background are about 15 ft. (4 meters) high. are mixed with gentle slopes, providing much variation in rocky intertidal habitat. Split frame, showing low tide and high tide from same view, Salt Point, California. Identical views Low tide, muddy bay, Bodega Bay, California. of a rocky intertidal area at a moderate low tide (left) Bays protected from winds, currents, and waves tend and moderate high tide (right). Tidal variation between to be shallow and muddy as sediments from rivers these two times was about 9 feet (2.7 m). accumulate in the basin. The receding tide leaves mudflats. High tide, Salt Point, mixed sandstone and hard rock boulders. Same beach as previous two slides, Low tide, muddy bay. In some bays, low tides expose note the absence of exposed algae on the rocks. vast areas of mudflats. The sea may recede several kilometers from the shoreline of high tide Tides Low tide, sandy beach.
    [Show full text]