DOCSLIB.ORG

Cryptochiton Stelleri) Grazing Performance And

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Cryptochiton Stelleri) Grazing Performance And THE EFFECTS OF ELEVATED TEMPERATURES ON GUMBOOT CHITON (CRYPTOCHITON STELLERI) GRAZING PERFORMANCE AND THERMOREGULATION EFFICIENCY By Lily Clare McIntire A Thesis Presented to The Faculty of Humboldt State University In Partial Fulfillment of the Requirements for the Degree Master of Science in Biology Committee Membership Dr. Paul E. Bourdeau, Committee Chair Dr. Bengt J. Allen, Committee Member Dr. Erik S. Jules, Committee Member Dr. Frank J. Shaughnessy, Committee Member Dr. Erik S. Jules, Graduate Coordinator December 2019 ABSTRACT THE EFFECTS OF ELEVATED TEMPERATURES ON GUMBOOT CHITON (CRYPTOCHITON STELLERI) GRAZING PERFORMANCE AND THERMOREGULATION EFFICIENCY Lily McIntire Rocky intertidal zones are some of the most thermally stressful environments on earth, where ectotherms deal with tidal fluctuations in air and water temperatures that can exceed thermal performance limits. However, not all intertidal ectotherms face the same exposure risk. On the northwest coast of the United States, summertime low tides occur during midday, exposing ectotherms to stressful temperatures. In contrast, cooler pre- dawn low tides in southern regions buffer ectotherms from thermal stress. Gumboot chitons (Cryptochiton stelleri) are a thermally sensitive intertidal grazer that range from southern California to Alaska, exposing them to a mosaic of thermal stress. I quantified chiton thermal performance limits in the laboratory, by testing the effects of elevated water and air temperatures on grazing. I also compared the thermoregulation efficiency of chitons from thermally-benign northern California (CA) sites with those from thermally- stressful San Juan Island (SJI), Washington sites using three components: 1) biomimetic thermal models deployed intertidally at three sites each in CA and SJI; 2) chiton body temperatures in the field; and 3) chiton thermal preference in a laboratory-based thermal gradient. I found that chiton thermal performance was reduced at 18℃ in water and ii reached their thermal performance limit at 20℃ in air, confirming previous work documenting thermal performance limits on gumboot chiton respiration. I also found that preferred temperatures of chitons were close to their thermal performance limits, but that they rarely achieved body temperatures that would maximize their performance in the field. This suggests that chitons are thermoregulating inefficiently with respect to maximizing performance, but instead may be minimizing exposure to detrimental thermal extremes. iii ACKNOWLEDGEMENTS I would like to thank my funding sources: CSU Council on Ocean Affairs, Science & Technology (COAST), the Marine Coastal Sciences Institute (MCSI), Friday Harbor Labs, the Pacific Northwest Shell Club, the Western Society of Malacologists, Malcom Oliphant Graduate Fund, the Brusca family, HSU Master’s Student Grant, and Sigma Xi Grant-in-Aid-of-Research. Thank you to my advisor, Dr. Paul Bourdeau, for always being supportive and pushing me to become a better scientist and person. He not only helped with developing my project and writing my thesis, he was also an invaluable help in the field and the laboratory, even if it meant installing loggers in the pouring rain. He gave up countless hours and sleep to help me complete this project and I am grateful for every edit and meeting. I would like to acknowledge my committee members for their help and feedback on my thesis. I would also like to thank all of my research assistants who helped in lab and came out into the field at 3 am for multiple days in a row and helped install loggers, take temperatures, and carry heavy buckets full of algae and gumboots. There are too many to name, but I would like to thank Melanie Dominguez, Crystal Hofer, Agustina Marroquin Martinez, and Viki Heller as they were the most consistent helpers that were with me since the beginning. iv All of my lab mates: Jessica Gravelle, Torre Flagor, Wesley Hull, Andrea Fieber, Johnny Roche, Angela Jones, Timothy McClure, and Kindall Murie, thank you for all the helpful feedback on presentations and help in the field and lab. I would like to thank Kindall, not only for helping me with field installs and lab work but being an ever- supportive roommate and friend without whom I would not have made it through graduate school. Jess also was a huge emotional support throughout this process. I could not have built my thermal gradient without Lewis McCrigler and Colin Wingfield in Environmental Engineering drilling holes through the aluminum and Kyle Weis helping me design and build it. I would like to thank Mike Nishizaki for lending me his thermal imaging camera while I was at Friday Harbor Labs. I would like to thank the director and staff (Grant Eberle and Kyle Weis) at the Telonicher Marine Lab for giving me the space and materials to carry out my laboratory experiments. In addition, I would like to thank the director and staff at Friday Harbor Labs for hosting me while I did my research on San Juan Island. Thanks to all the office managers, Yvonne Kugies, Stephanie Stephen, and Liz Weaver for helping me with paperwork and moral support. Finally, I would like to thank my family, my parents, and sisters, Meagan and Ella, my best friend, Tatiana Kotas, and my countless other friends who encouraged and supported me through this process even from Colorado, Kentucky, Florida, and San Diego, and often became unwitting field assistants. v TABLE OF CONTENTS ABSTRACT ........................................................................................................................ ii ACKNOWLEDGEMENTS ............................................................................................... iv LIST OF TABLES ............................................................................................................ vii LIST OF FIGURES ......................................................................................................... viii CHAPTER 1: THE EFFECTS OF ELEVATED TEMPERATURES ON GUMBOOT CHITON GRAZING PERFORMANCE ............................................................................ 1 INTRODUCTION .............................................................................................................. 1 MATERIALS AND METHODS ........................................................................................ 5 Effects of water and air temperature on gumboot chiton grazing performance ............. 5 Effects of air and water temperature on macroalgal palatability .................................... 9 Quantifying frequency of exposure to thermal extremes .............................................. 11 Statistical analyses ........................................................................................................ 13 RESULTS ......................................................................................................................... 15 DISCUSSION ................................................................................................................... 20 CHAPTER 2: GEOGRAPHIC VARIATION IN GUMBOOT CHITON THERMOREGULATION EFFICIENCY ........................................................................ 25 INTRODUCTION ............................................................................................................ 25 METHODS ....................................................................................................................... 29 Statistical analyses ........................................................................................................ 36 RESULTS ......................................................................................................................... 37 DISCUSSION ................................................................................................................... 43 LITERATURE CITED ..................................................................................................... 50 vi LIST OF TABLES Table 1. Results from the Games-Howell post hoc test for water temperature effects on gumboot chiton (Cryptochiton stelleri) grazing rates. ...................................................... 16 Table 2. Results from the Mann-Whitney U post hoc tests for air temperature effects on gumboot chiton (Cryptochiton stelleri) grazing rates. ...................................................... 17 Table 3. The aerial thermal limits of intertidal organisms in the eastern north Pacific. ... 24 Table 4. Set of variables that were used to calculate thermoregulation efficiency (E) of gumboot chitons (Cryptochiton stelleri). .......................................................................... 30 Table 5. Results from the post-hoc Tukey HSD Test comparing the Tb’s of gumboot chitons (Cryptochiton stelleri) in different habitats between SJI, WA (SJI) and CA (CA). Bold values indicate statistically significant differences at = 0.10. .............................. 41 vii LIST OF FIGURES Figure 1. Map of northern California field sites where “roboboots” were installed during summer 2019. Baker Beach (41° 2'57.37"N, 124° 7'40.54"W), Devil’s Gate (40°23'55.50"N, 124°22'53.72"W), Belinda Point (39°23'56.5"N, 123°49'10.1"W). ........ 6 Figure 2. (a) A live chiton (left) next to a “roboboot”, pre-installation, in the field. (b) The temperatures of “roboboots” (red line, n = 5) and live chitons (black line, n = 5) taken every 20 minutes over the course of 6 hours. Chitons and roboboots were left in air until they reached 30℃, then placed in flow-through sea tables to quantify how both warmed
Load more

Recommended publications
  • GASTROPOD CARE SOP# = Moll3 PURPOSE: to Describe Methods Of
    GASTROPOD CARE SOP# = Moll3 PURPOSE: To describe methods of care for gastropods. POLICY: To provide optimum care for all animals. RESPONSIBILITY: Collector and user of the animals. If these are not the same person, the user takes over responsibility of the animals as soon as the animals have arrived on station. IDENTIFICATION: Common Name Scientific Name Identifying Characteristics Blue topsnail Calliostoma - Whorls are sculptured spirally with alternating ligatum light ridges and pinkish-brown furrows - Height reaches a little more than 2cm and is a bit greater than the width -There is no opening in the base of the shell near its center (umbilicus) Purple-ringed Calliostoma - Alternating whorls of orange and fluorescent topsnail annulatum purple make for spectacular colouration - The apex is sharply pointed - The foot is bright orange - They are often found amongst hydroids which are one of their food sources - These snails are up to 4cm across Leafy Ceratostoma - Spiral ridges on shell hornmouth foliatum - Three lengthwise frills - Frills vary, but are generally discontinuous and look unfinished - They reach a length of about 8cm Rough keyhole Diodora aspera - Likely to be found in the intertidal region limpet - Have a single apical aperture to allow water to exit - Reach a length of about 5 cm Limpet Lottia sp - This genus covers quite a few species of limpets, at least 4 of them are commonly found near BMSC - Different Lottia species vary greatly in appearance - See Eugene N. Kozloff’s book, “Seashore Life of the Northern Pacific Coast” for in depth descriptions of individual species Limpet Tectura sp. - This genus covers quite a few species of limpets, at least 6 of them are commonly found near BMSC - Different Tectura species vary greatly in appearance - See Eugene N.
    [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 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]
  • Grade Levels K-1
    Grade Levels K-1 Tlingit Cultural Significance Since time immemorial Tlingit people have survived using what nature provides. Southeast Alaska has a rich, extensive coastline, so Tlingit people gather numerous beach creatures that nourish them. They in turn respect the creatures of the tides and beaches that sustain them. During winter and early spring, when fresh foods weren’t always A series of elementary level thematic units available, they began the tradition of gathering food from the beaches. featuring Tlingit language, culture and history This unit is best suited for the spring because many schools conduct Sea Week/ were developed in Juneau, Alaska in 2004-6. Month activities during April or May. The project was funded by two grants from the U.S. Department of Education, awarded Elder/Culture Bearer Role to the Sealaska Heritage Institute (Boosting Academic Achievement: Tlingit Language Elders/Culture bearers enrich this unit through their knowledge of beach creatures Immersion Program, grant #92-0081844) and gathering and processing techniques. In addition they can help teach the and the Juneau School District (Building on Lingít names of beach creatures and enrich the activities with personalized cultural Excellence, grant #S356AD30001). and historical knowledge. Lessons and units were written by a team of teachers and specialists led by Nancy Overview Douglas, Elementary Cultural Curriculum Lesson #1—Old Woman of the Tides. This Tlingit legend provides a cultural Coordinator, Juneau School District. The context for learning about inter-tidal sea life. Students listen to the legend, team included Juneau teachers Kitty Eddy, sequence events from the story and retell it to others.
    [Show full text]
  • XIV. Appendices
    Appendix 1, Page 1 XIV. Appendices Appendix 1. Vertebrate Species of Alaska1 * Threatened/Endangered Fishes Scientific Name Common Name Eptatretus deani black hagfish Lampetra tridentata Pacific lamprey Lampetra camtschatica Arctic lamprey Lampetra alaskense Alaskan brook lamprey Lampetra ayresii river lamprey Lampetra richardsoni western brook lamprey Hydrolagus colliei spotted ratfish Prionace glauca blue shark Apristurus brunneus brown cat shark Lamna ditropis salmon shark Carcharodon carcharias white shark Cetorhinus maximus basking shark Hexanchus griseus bluntnose sixgill shark Somniosus pacificus Pacific sleeper shark Squalus acanthias spiny dogfish Raja binoculata big skate Raja rhina longnose skate Bathyraja parmifera Alaska skate Bathyraja aleutica Aleutian skate Bathyraja interrupta sandpaper skate Bathyraja lindbergi Commander skate Bathyraja abyssicola deepsea skate Bathyraja maculata whiteblotched skate Bathyraja minispinosa whitebrow skate Bathyraja trachura roughtail skate Bathyraja taranetzi mud skate Bathyraja violacea Okhotsk skate Acipenser medirostris green sturgeon Acipenser transmontanus white sturgeon Polyacanthonotus challengeri longnose tapirfish Synaphobranchus affinis slope cutthroat eel Histiobranchus bathybius deepwater cutthroat eel Avocettina infans blackline snipe eel Nemichthys scolopaceus slender snipe eel Alosa sapidissima American shad Clupea pallasii Pacific herring 1 This appendix lists the vertebrate species of Alaska, but it does not include subspecies, even though some of those are featured in the CWCS.
    [Show full text]
  • OREGON ESTUARINE INVERTEBRATES an Illustrated Guide to the Common and Important Invertebrate Animals
    OREGON ESTUARINE INVERTEBRATES An Illustrated Guide to the Common and Important Invertebrate Animals By Paul Rudy, Jr. Lynn Hay Rudy Oregon Institute of Marine Biology University of Oregon Charleston, Oregon 97420 Contract No. 79-111 Project Officer Jay F. Watson U.S. Fish and Wildlife Service 500 N.E. Multnomah Street Portland, Oregon 97232 Performed for National Coastal Ecosystems Team Office of Biological Services Fish and Wildlife Service U.S. Department of Interior Washington, D.C. 20240 Table of Contents Introduction CNIDARIA Hydrozoa Aequorea aequorea ................................................................ 6 Obelia longissima .................................................................. 8 Polyorchis penicillatus 10 Tubularia crocea ................................................................. 12 Anthozoa Anthopleura artemisia ................................. 14 Anthopleura elegantissima .................................................. 16 Haliplanella luciae .................................................................. 18 Nematostella vectensis ......................................................... 20 Metridium senile .................................................................... 22 NEMERTEA Amphiporus imparispinosus ................................................ 24 Carinoma mutabilis ................................................................ 26 Cerebratulus californiensis .................................................. 28 Lineus ruber .........................................................................
    [Show full text]
  • Fish Bulletin 161. California Marine Fish Landings for 1972 and Designated Common Names of Certain Marine Organisms of California
    UC San Diego Fish Bulletin Title Fish Bulletin 161. California Marine Fish Landings For 1972 and Designated Common Names of Certain Marine Organisms of California Permalink https://escholarship.org/uc/item/93g734v0 Authors Pinkas, Leo Gates, Doyle E Frey, Herbert W Publication Date 1974 eScholarship.org Powered by the California Digital Library University of California STATE OF CALIFORNIA THE RESOURCES AGENCY OF CALIFORNIA DEPARTMENT OF FISH AND GAME FISH BULLETIN 161 California Marine Fish Landings For 1972 and Designated Common Names of Certain Marine Organisms of California By Leo Pinkas Marine Resources Region and By Doyle E. Gates and Herbert W. Frey > Marine Resources Region 1974 1 Figure 1. Geographical areas used to summarize California Fisheries statistics. 2 3 1. CALIFORNIA MARINE FISH LANDINGS FOR 1972 LEO PINKAS Marine Resources Region 1.1. INTRODUCTION The protection, propagation, and wise utilization of California's living marine resources (established as common property by statute, Section 1600, Fish and Game Code) is dependent upon the welding of biological, environment- al, economic, and sociological factors. Fundamental to each of these factors, as well as the entire management pro- cess, are harvest records. The California Department of Fish and Game began gathering commercial fisheries land- ing data in 1916. Commercial fish catches were first published in 1929 for the years 1926 and 1927. This report, the 32nd in the landing series, is for the calendar year 1972. It summarizes commercial fishing activities in marine as well as fresh waters and includes the catches of the sportfishing partyboat fleet. Preliminary landing data are published annually in the circular series which also enumerates certain fishery products produced from the catch.
    [Show full text]
  • Evolutionary Consequences of Food Chain Length in Kelp Forest Communities (Biogeography/Coevolution/Herbivory/Phlorotannins/Predation) PETER D
    Proc. Natl. Acad. Sci. USA Vol. 92, pp. 8145-8148, August 1995 Ecology Evolutionary consequences of food chain length in kelp forest communities (biogeography/coevolution/herbivory/phlorotannins/predation) PETER D. STEINBERG*, JAMES A. ESTEStt, AND FRANK C. WINTER§ *School of Biological Sciences, University of New South Wales, P.O. Box 1, Kensington, New South Wales, 2033, Australia; tNational Biological Service, A-316 Earth and Marine Sciences Building, University of California, Santa Cruz, CA 95064; and §University of Auckland, Leigh Marine Laboratory, P.O. Box 349, Warkworth, New Zealand Communicated by Robert T. Paine, University of Washington, Seattle, WA, May 12, 1995 ABSTRACT Kelp forests are strongly influenced by mac- consistently important structuring processes throughout the roinvertebrate grazing on fleshy macroalgae. In the North food web. Under these conditions, we would predict that Pacific Ocean, sea otter predation on macroinvertebrates top-level consumers are resource limited. Consequently, the substantially reduces the intensity of herbivory on macroal- next lower trophic level should be consumer limited, in turn gae. Temperate Australasia, in contrast, has no known pred- causing the level below that (if one exists) to again be resource ator of comparable influence. These ecological and biogeo- limited. Looking downward through the food web from this graphic patterns led us to predict that (i) the intensity of very generalized perspective, a pattern emerges of strongly herbivory should be greater in temperate Australasia than in interacting couplets of adjacent trophic levels. Given these the North Pacific Ocean; thus (ii) Australasian seaweeds have circumstances, the interactive coupling between plants and been under stronger selection to evolve chemical defenses and herbivores should be strong in even-numbered systems and (iii) Australasian herbivores have been more strongly selected weak in odd-numbered systems, a prediction recently substan- to tolerate these compounds.
    [Show full text]
  • Investigating the Ecological Consequences of Sea Otter Recovery in the Central Coast of British Columbia
    Investigating the Ecological Consequences of Sea Otter Recovery in the Central Coast of British Columbia Part I. Sea Otters, Kelp Forests & Recovery of Northern Abalone Part II. Do Sea Otters Trigger Trophic Cascades in the Rocky Intertidal? Summary Field Report of a 10-day pilot study conducted May 22-31, 2010 Principal Investigators: Lynn Lee & Dr. Anne Salomon Coastal Marine Ecology and Conservation Lab School of Resource and Environmental Management (REM) Hakai Network for Coastal People, Ecosystems and Management Simon Fraser University (SFU) Co-Investigators: Brooke Davis, SFU Environmental Sciences Undergraduate Student Dr. Jane Watson, Vancouver Island University Matt Drake, SFU Biology Undergraduate Student Julie Carpenter, Heiltsuk Integrated Resource Management Department (HIRMD) Stewart Humchitt, Heiltsuk community Submitted to: Frank Brown & Ross Wilson, Heiltsuk Integrated Resource Management Department Steven Hodgson, BC Parks and Protected Areas Eric Peterson & Christina Munck, Tula Foundation Report dated: March 2011 ACKNOWLEDGEMENTS Special thanks to Leandre Vigneault, Taimen Lee Vigneault, Jane Watson, Stan Hutchings and Karen Hansen for volunteering their time and enthusiasm to the field research; to Stewart Humchitt and Julie Carpenter for sharing their knowledge of Heiltsuk territory and lively discussions; to Rod Wargo for competent navigation throughout the Central Coast archipelago; to the staff of Hakai Beach Institute for keeping us well-fed and welcomed; and to Mark Wunsch for photos and video footage. to the Heiltsuk Integrated Resource Management Department for collaborating in this pilot study, including permission to conduct research in Heiltsuk traditional territory. FINANCIAL SUPPORT This project was supported by the Tula Foundation and the Hakai Beach Institute. Financial support was also provided by Anne Salomon’s Coastal Marine Ecology & Conservation (CMEC) Lab through Natural Science and Engineering Research Council of Canada (NSERC) grants.
    [Show full text]
  • Intertidal Narrative
    Warner Pacific College Boiler Bay Intertidal Trip - Dwight J. Kimberly This is a summary of things to look for on the field trip and a few suggestions to make the trip more enjoyable for you. Be careful where you step because the intertidal floor is the home of many animals. No animals will be collected without a permit. When close to the surf, watch the ocean at all times. Take your time climbing around the rocks. They are slick and a fall could break a bone or remove skin. Use the accompanying checklist to key the phyla that you have learned in the course The following discussion is based upon Ricketts and Calvin, Between the Pacific Tides. Three factors modify the intertidal marine fauna: 1) wave shock, 2) tidal exposure and 3) type of bottom. You will see an example of the protected rocky coast in which the shock of the waves is reduced by the influence of a long sloping shelf. Other possible modifications which produce the same result are offshore reefs, headlands, islands or large kelp beds. The bottom is typically rocky and affords a firm substrate for animal attachment to plants and animals. By turning over rocks you will uncover a myriad of animals, but at the same time expose them to the fatal effects of the sun. Therefore, replace the rocks as you found them to assure the survival of these animals. The zonation of the animal life as a result of the tides is apparent. Familiarize yourself with the zones and their characteristics. ZONE 1.
    [Show full text]
  • GUMBOOT CHITON Cryptochiton Stelleri Middendorff, 1846 (Acanthochitonidae)
    GUMBOOT CHITON Cryptochiton stelleri Middendorff, 1846 (Acanthochitonidae) Global rank G5 (26Jun2006) State rank S5 (26Jun2006) State rank reasons Overall population and trends unknown, but the species is considered locally abundant and widespread in coastal areas. Threatened by human harvest; low recruitment rates make the species vulnerable to overharvest. There is also concern about contamination as a result of individuals are rarely observed (MacGinitie and coastal development and oil spills and the MacGinitie 1968). potential effects of climatic warming. Ecology TaxonomyRecent work by Okusu et al. (2003) Very few predators; they include the lurid places the genus Cryptochiton in a subclade rocksnail (Ocinebrina lurida), tidepool sculpin within the Acanthochitonina along with Tonicella, (Oligocottus maculosus), river otter (Lontra Mopalia, and Katharina, based on genetic and canadensis; O’Clair and O’Clair 1998) and the morphological similarities. large asteroid (Pycnopodia helianthoides; Yates 1989). A traditional source of food for humans, General description but the meat is very tough (Harbo 1997, O’Clair The largest chiton in the world, up to 33 cm long. and O’Clair 1998). The purple urchin In Southeast Alaska, typically smaller, about 15 (Strongylocentrotus purpuratus) and red urchin cm (Yates 1989, O’Clair and O’Clair 1998). (S. franciscanus) may compete with the gumboot Species is unique among chitons because all chiton for space and food (Yates 1989). May be eight plates are completely concealed by the an indirect commensal to coralline algae by thick and leathery reddish brown or brown mantle eating the fleshy red algae that grows on its (Field and Field 1999, Cowles 2005). The surface and reducing the negative effects of underside is yellow or orange, with a broad foot algae overgrowth (Yates 1989).
    [Show full text]
  • Tezula Funebralis Shell Height Variance in the Intertidal Zones
    Laci Uyesono Structural Comparison Adaptations of Marine Animals Tezula funebralis Shell height variance in the Intertidal zones Introduction The Pacific Coast of the United States is home to a great diversity of biota that populates both extremes, from the constantly battered rocks to the calm ocean floor. As a result of this diversity or because of this diversity there are distinct zones created by the physical, chemical, and biological constraints of the organisms. Tegula funebralis (T funebralis) commonly called the Black Turban shell is found in the low to high intertidal zones of rocky shores on or under rocks grazing on macroalgae. T funebralis can be purple to black in color with four whirls on top (usually worn down to a light color at the top), average 3cm in diameter, and can live up to 100 years (Sept 1999). T funebralis' density tends to be greater in the mid to high intertidal zone due to predation by octopus, Pisaster ochraceous, and crabs (Fawcett 1984). They also show a pattern of distribution where juveniles (those not of reproductive size —14mm) stay in the mid intertidal zone because it is midway between the physical stress of desiccation and the biological stress of predation (Fawcett 1984). Generally larger snails are able to withstand desiccation more then smaller snails, but larger Tegula have a greater advantage living lower in the intertidal even at the risk of predation. They are kept at moderate levels in this zone because Pisaster feeds on them and reduces their density, which then increases the food abundance for those who remain (Doering and Phillips 1983).
    [Show full text]