Mapping California's Important Bird Areas

Total Page:16

File Type:pdf, Size:1020Kb

Mapping California's Important Bird Areas Mapping California’s Important Bird Areas Mapping California’s Important Bird Areas National Audubon Society © 2008 For questions or comments, please visit our website (http://www.ca.audubon.org/iba), or contact: Andrea Jones, Director of Important Bird Areas Program, Audubon California, 601 Embarcadero, Suite 14, Morro Bay, CA 93442, TEL: (805) 772-1995, FAX: (805) 772- 1995, Email: [email protected]. Mike Perlmutter, Bay Area Conservation Coordinator, Audubon California, 4225 Hollis Street, Emeryville, CA 94608, TEL: (510) 601-1866 ext. 231, FAX: (510) 601-1954, Email: [email protected]. William Monahan, Senior GIS Scientist, Audubon California, 4225 Hollis Street, Emeryville, CA 94608, TEL: (510) 601-1866 ext. 232, FAX: (510) 601-1954, Email: [email protected]. David Yun, GIS Supervisor, City of San Luis Obispo, 919 Palm Street, San Luis Obispo, CA 93401. TEL: (805) 781-7189, FAX: (805) 781-7198, Email: [email protected]. Cover: Black Rail (Laterallus jamaicensis) by John James Audubon. Summary Important Bird Areas (IBAs) identify sites that provide essential habitat for birds. As such they establish a useful framework for helping guide efforts to conserve birds statewide. Audubon California determined that detailed IBA maps are necessary for on-the-ground IBA conservation to be planned and carried out in an effective and efficient fashion. Beginning in 2006, Audubon California set out to define and map the geographic boundaries of the 148 sites originally designated by bird experts around the state. The present document, Mapping California’s Important Bird Areas, serves as a general technical report describing our mapping methodology and basic summary results. It accompanies Version 1.0 of our new Geographic Information Systems (GIS) database containing the boundaries and attributes of California’s Important Bird Areas. Acknowledgments David Yun’s students from California Polytechnic State University, Sarah Bailey and Kerri Johnson, conducted their senior thesis on this project and developed the methodology that we applied across California. They produced excellent reports and were a pleasure to work with. We also thank the following students who assisted with IBA mapping through their GIS coursework: Jackie Hancock, Ninah Hartley, Melinda Elster, and Tony Kochis. Meghan Jerolaman and Julie Messer also completed their senior thesis on the IBA mapping project and are thanked especially for their dedication to work through the summer to see the original map finished. During the review phase, Melinda Elster and Karen Velas both contributed considerable and valuable time to refining and editing IBA maps and providing good humor and expertise to the process. In the San Francisco Bay region, we thank the San Francisco Estuary Institute for providing access to the San Francisco Bay Ecoatlas, Tim Doherty at the Bay Conservation and Development Commission for providing information on and access to several key San Francisco Bay GIS datasets, Ryan Branciforte of the Bay Area Open Space Council for putting together the Bay Area Upland Goals GIS packet and BPAD, Tracy Love at the California Department of Fish and Game for providing California state park and parcel data for Bay Area counties, and Christina Freeman and Cindy Shafer at California State Parks and Meg Peterson at East Bay Regional Parks for providing GIS data for their parks. Glenn Olson, Graham Chisholm, Gary Langham, Dan Taylor, Garrison Frost, Garry George, Alison Sheehey, Rodd Kelsey, and Vance Russell from Audubon California provided important feedback throughout the mapping process. Dan Cooper is thanked for compiling the original site descriptions. While too many people to name, we thank all Audubon California chapters, bird clubs, and birding experts for originally nominating IBAs, editing the site descriptions, and helping delineate the site boundaries. Finally, we thank the Environmental Systems Research Institute for their generous Conservation Program Grant to Audubon California, which provided us with multiple licenses of ArcGIS software, training courses for staff, and free access to ArcGIS Online services. Table of Contents Overview..................................................................................................................... 1 Background ................................................................................................................ 1 Important Bird Areas.............................................................................................. 1 California’s Important Bird Areas.......................................................................... 1 Methods ..................................................................................................................... 3 Creating initial draft maps..................................................................................... 3 Review and refinement of boundaries................................................................... 7 Site summary statistics.......................................................................................... 8 Results ....................................................................................................................... 9 Accuracy.................................................................................................................. 9 Name revisions....................................................................................................... 9 Area ....................................................................................................................... 10 Land ownership .................................................................................................... 10 Land cover............................................................................................................. 12 Political boundaries ............................................................................................. 12 Discussion................................................................................................................ 13 Map representation.............................................................................................. 13 Data dissemination and future updates ............................................................. 13 Conservation ownership and stewardship ......................................................... 13 Future analysis ..................................................................................................... 14 References................................................................................................................ 15 Appendix 1 Example review form ........................................................................................A1.1 Appendix 2 Attributes provided in the geodatabase..........................................................A2.1 Appendix 3 Basic site attributes..........................................................................................A3.1 Appendix 4 Important Bird Areas by county .......................................................................A4.1 Appendix 5 Habitat associations.........................................................................................A5.1 Appendix 6 Important Bird Areas by Senate District..........................................................A6.1 Appendix 7 Important Bird Areas by Congressional District .............................................A7.1 Appendix 8 Important Bird Areas by Assembly District .....................................................A8.1 Mapping California’s Important Bird Areas, Audubon California, Page i Overview Important Bird Areas (IBAs) identify essential sites that provide habitat for (i) rare, threatened or endangered birds, (ii) exceptionally large congregations of shorebirds, or (iii) exceptionally large congregations of waterfowl. In an effort to promote conservation and awareness of these areas, Audubon California set out to define and map the geographic boundaries of all IBAs in California using a Geographic Information System (GIS). The present document serves as the general technical report describing our mapping methodology and basic summary results. Background Important Bird Areas Classification of Important Bird Areas (IBAs) began in Europe in 1985 by Birdlife International as a means to identify and encourage conservation of habitats for preserving avian biodiversity. This international conservation program was a response to growing concerns over bird habitat fragmentation and loss. Since the program’s inception, IBAs have been designated in six continents, nearly 200 countries and territories, and 48 of the 50 United States. As of 2008, there were over 10,000 IBAs throughout the world. While conferring no regulatory authority, a site's designation as an IBA is a powerful distinction which can be utilized to leverage conservation efforts. IBA status increases opportunities for land acquisition, restoration, conservation planning, public outreach, advocacy, and environmental education. In some cases, the IBA program has been used to establish legal protections for bird habitat. For example, the IBAs in New York State served as a model for the State Bird Conservation Area Program, which now legally integrates bird conservation into agency planning, management, and research. California’s Important Bird Areas The American Bird Conservatory and the National Audubon Society joined in the development of an IBA program in the United States. From 1995 to 1998, the California
Recommended publications
  • Elkhorn Slough Estuary
    A RICH NATURAL RESOURCE YOU CAN HELP! Elkhorn Slough Estuary WATER QUALITY REPORT CARD Located on Monterey Bay, Elkhorn Slough and surround- There are several ways we can all help improve water 2015 ing wetlands comprise a network of estuarine habitats that quality in our communities: include salt and brackish marshes, mudflats, and tidal • Limit the use of fertilizers in your garden. channels. • Maintain septic systems to avoid leakages. • Dispose of pharmaceuticals properly, and prevent Estuarine wetlands harsh soaps and other contaminants from running are rare in California, into storm drains. and provide important • Buy produce from local farmers applying habitat for many spe- sustainable management practices. cies. Elkhorn Slough • Vote for the environment by supporting candidates provides special refuge and bills favoring clean water and habitat for a large number of restoration. sea otters, which rest, • Let your elected representatives and district forage and raise pups officials know you care about water quality in in the shallow waters, Elkhorn Slough and support efforts to reduce question: How is the water in Elkhorn Slough? and nap on the salt marshes. Migratory shorebirds by the polluted run-off and to restore wetlands. thousands stop here to rest and feed on tiny creatures in • Attend meetings of the Central Coast Regional answer: It could be a lot better… the mud. Leopard sharks by the hundreds come into the Water Quality Control Board to share your estuary to give birth. concerns and support for action. Elkhorn Slough estuary hosts diverse wetland habitats, wildlife and recreational activities. Such diversity depends Thousands of people come to Elkhorn Slough each year JOIN OUR EFFORT! to a great extent on the quality of the water.
    [Show full text]
  • Your April 2017 Neighborhoods First New...Ter
    12/12/2017 Your April 2017 Neighborhoods First Newsletter - Mike Bonin - Council District 11 ABOUT MIKE COUNCIL STAFF NEWS ISSUES NEIGHBORHOODS MEDIA TAKE ACTION HOME » NEWS Your April 2017 Neighborhoods First Newsletter Sign Up For Updates Posted by David Graham-Caso 721.80sc on April 28, 2017 · Flag · Add your reaction April 2017 Welcome to the April issue of Mike Bonin's "Neighborhoods First Newsletter!” IN THIS ISSUE: Construction begins on Mar Vista’s Great Street, Mike fights for funding for a life-saving program to end traffic fatalities, and an effort launches Contact Our Ofce to protect people from dangerous oil and gas wells in our neighborhoods... but first, please read this month's Neighborhoods First Profile about a Pacific Palisades neighbor who is helping kids see a bright future ahead of them. Connect with Facebook You can find out more about Mike, meet your CD11 staff and see the latest Connect with Twitter videos and updates from the Westside on our website at www.11thdistrict.com. And remember to like Mike's Facebook page to see the latest news about your neighborhood. Councilmember Mike… 5,188 likes Liked You and 17 other friends like this Vision to Learn: Pacific Palisades’ Austin Beutner Is Helping Kids See Success Pacific Palisades neighbor Austin Beutner has served Los Angeles in a variety of capacities - as First Deputy Mayor, interim head of the Los Angeles Department Water and Power, and publisher and CEO of the Los Angeles Times. In 2012, however, Beutner founded Vision To Learn - an organization that serves Los Angeles in a different, more focused way.
    [Show full text]
  • 140 Years of Railroading in Santa Cruz County by Rick Hamman
    140 Years of Railroading in Santa Cruz County By Rick Hamman Introduction To describe the last 140 years of area railroading in 4,000 words, or two articles, seems a reasonable task. After all, how much railroad history could there be in such a small county? In the summer of 1856 Davis & Jordon opened their horse powered railroad to haul lime from the Rancho Canada Del Rincon to their wharf in Santa Cruz. Today, the Santa Cruz, Big Trees & Pacific Railway continues to carry freight and passengers through those same Rancho lands to Santa Cruz. Between the time span of these two companies there has been no less than 37 different railroads operating at one time or another within Santa Cruz County. From these various lines has already come sufficient history to fill at least eight books and numerous historical articles. Many of these writings are available in your local library. As we begin this piece the author hopes to give the reader an overview and insight into what railroads have meant for Santa Cruz County, what they provide today, and what their relevance could be for tomorrow. Before There Were Railroads As people first moved west in search of gold, and later found reason to remain, Santa Cruz County offered many inducements. It was already well known because of its proximity to the former Alta California capital at Monterey, its Mission at Santa Cruz and its excellent weather. Further, within its boundaries were vast mineral deposits in the form of limestone and aggregates, rich alluvial farming soils and fertile orchard lands, and billions of standing board feet of uncut pine and redwood lumber to supply the construction of the San Francisco and Monterey bay areas.
    [Show full text]
  • Industrial Context Work Plan
    LOS ANGELES CITYWIDE HISTORIC CONTEXT STATEMENT Context: Industrial Development, 1850-1980 Prepared for: City of Los Angeles Department of City Planning Office of Historic Resources September 2011; rev. February 2018 The activity which is the subject of this historic context statement has been financed in part with Federal funds from the National Park Service, Department of the Interior, through the California Office of Historic Preservation. However, the contents and opinions do not necessarily reflect the views or policies of the Department of the Interior or the California Office of Historic Preservation, nor does mention of trade names or commercial products constitute endorsement or recommendation by the Department of the Interior or the California Office of Historic Preservation. This program receives Federal financial assistance for identification and protection of historic properties. Under Title VI of the Civil Rights Act of 1964, Section 504 of the Rehabilitation Act of 1973, and the Age Discrimination Act of 1975, as amended, the U.S. Department of the Interior prohibits discrimination on the basis of race, color, national origin, disability, or age in its federally assisted programs. If you believe you have been discriminated against in any program, activity, or facility as described above, or if you desire further information, please write to: Office of Equal Opportunity, National Park Service; 1849 C Street, N.W.; Washington, D.C. 20240 SurveyLA Citywide Historic Context Statement Industrial Development, 1850-1980 TABLE
    [Show full text]
  • Initial Study Appendix B
    Uvas Road at Little Uvas Creek Bridge Replacement Project Biological Assessment Biological Assessment Uvas Road over Little Uvas Creek Bridge Replacement Project (37C-0095/37C-0601 [new]) Near Morgan Hill, Santa Clara County, California 04-SCL-0-CR Federal Project Number BRLO 5937(124) Caltrans District 04 November 2015 Biological Assessment Uvas Road over Little Uvas Creek Bridge Replacement Project (37C-0095/37C-0601 [new]) Near Morgan Hill, Santa Clara County, California 04-SCL-0-CR Federal Project Number BRLO 5937(124) Caltrans District 04 November 2015 STATE OF CALIFORNIA Department of Transportation and Santa Clara County Roads and Airports Department Prepared By: ___________________________________ Date: ____________ Patrick Boursier, Principal (408) 458-3204 H. T. Harvey & Associates Los Gatos, California Approved By: ___________________________________ Date: ____________ Solomon Tegegne, Associate Civil Engineer Santa Clara County Roads and Airports Department Highway and Bridge Design 408-573-2495 Concurred By: ___________________________________ Date: ____________ Tom Holstein Environmental Branch Chief Office of Local Assistance Caltrans, District 4 Oakland, California 510-286-5250 For individuals with sensory disabilities, this document is available in Braille, large print, on audiocassette, or computer disk. To obtain a copy in one of these alternate formats, please call or write to the Santa Clara County Roads and Airports Department: Solomon Tegegne Santa Clara County Roads and Airports Department 101 Skyport Drive San Jose, CA 95110 408-573-2495 Summary of Findings, Conclusions and Determinations Summary of Findings, Conclusions and Determinations The Uvas Road at Little Uvas Creek Bridge Replacement Project (proposed project) is proposed by the County of Santa Clara Roads and Airports Department in cooperation with the Office of Local Assistance of the California Department of Transportation (Caltrans), and this Biological Assessment (BA) has been prepared following Caltrans’ procedures.
    [Show full text]
  • Thomas L. Davis & Jay S. Namson
    S KERN A FRONT N ROUND 1' McDONALD RIO BRAVO POSO MOUNTAIN ANTICLINE CREEK Thomas L. Davis & Jay S. Namson J 3' SOUTH SAN JOAQUINROSEDALE VALLEY KERN U RIVER BELRIDGE SEVENTH RANCH A STANDARD N CHICO-MARTINEZ GEOLOGISTS BOWERBANK KERN BLUFF GREELEY F ROSEDALE LA PANZA RANGE A U ANT HILL CALDERS L FRUITVALE CORNER 592 Poli St., Ventura, CA 93001 T ESTERO CYMRIC NORTHEAST H Ph:(805) 653-2435, Fax:(805) 653-2459 email:[email protected] BAY ENGLISH COLONY BAKERSFIELD EDISON U CARRIZO PLAIN EAST TEMBLOR GOOSLOO UNION WEST BELLEVUE BELLEVUE E S AVENUE R McCLUNG A TEMBLOR RANCH H N STRAND U McKITTRICK TEMBLOR CANAL Southern California Cross Section Study Map E STOCKDALE R A RAILROAD GAP EDISON R O N IN F C A D KERN SUMNER SAN LUIS VALLEY O U CANFIELD Showing 2012 AAPG Annual Mtg Field Trip Stops N L R NORTH RANCH A T BELGIAN ELK HILLS ANTICLINE COLES LEVEE D B E TEN SAN LUIS A - N C I A ASPHALTO SECTION A C G BUENA VISTA VALLEYELK HILLS (Field Trip #5, April 21 & 22, 2012) SODA SOUTH OBISPO IM H S S 4 I R COLES Field Trip Stop IE M P 5' LAKESIDE R IN LAKE E LEVEE MOUNTAIN N E G C T F VIEW PT. SAN LUIS O N A F R E U A U A LT I E F T SOUTH LAKESIDE SANTA LUCIA RANGE A S U MIDWAY-SUNSET A U P S C BUENA VISTA HILLS L F L A ARROYO GRANDE T U A BUENA T T S BUENA VISTA Y U S VISTA A L PALOMA H M T From: thomasldavisgeologist.com; go to downloads F LAKE U A A TEHACHAPI MOUNTAINS A CARRIZO PLAIN U BED F 4' L T T W S A W RANGE KERN LAKE L N U M U E H BED Date: May 24.
    [Show full text]
  • Birding Northern California by Jean Richmond
    BIRDING NORTHERN CALIFORNIA Site Guides to 72 of the Best Birding Spots by Jean Richmond Written for Mt. Diablo Audubon Society 1985 Dedicated to my husband, Rich Cover drawing by Harry Adamson Sketches by Marv Reif Graphics by dk graphics © 1985, 2008 Mt. Diablo Audubon Society All rights reserved. This book may not be reproduced in whole or in part by any means without prior permission of MDAS. P.O. Box 53 Walnut Creek, California 94596 TABLE OF CONTENTS Introduction . How To Use This Guide .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. Birding Etiquette .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. Terminology. Park Information .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 5 One Last Word. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 5 Map Symbols Used. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 6 Acknowledgements .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 6 Map With Numerical Index To Guides .. .. .. .. .. .. .. .. .. 8 The Guides. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 10 Where The Birds Are. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 158 Recommended References .. .. .. .. .. .. .. .. .. .. .. .. .. .. 165 Index Of Birding Locations. .. .. .. .. .. .. .. .. .. .. .. .. .. 166 5 6 Birding Northern California This book is a guide to many birding areas in northern California, primarily within 100 miles of the San Francisco Bay Area and easily birded on a one-day outing. Also included are several favorite spots which local birders
    [Show full text]
  • Farallon Islands and Noon Day Rock, Supports the Largest Seabird Nesting Colony South of Alaska
    U.S. Fish & Wildlife Service Farallon National Wildlife Refuge Photo: ©PRBO Dense colonies of common murres and colorful puffins cloak cliff faces and crags, while two-ton elephant seals fight fierce battles for breeding sites on narrow wave-etched terraces below. Natural History Surrounded by cold water and plenty of food Pt. Reyes San Rafael G ulf o f Fa Golden ra ll Gate on s Bridge iles Oakland 28 M San Francisco C a li fo Fremont rn PACIFIC OCEAN ia San Jose Farallon National Wildlife Refuge, made up of all the Farallon Islands and Noon Day Rock, supports the largest seabird nesting colony south of Alaska. Thirteen seabird species numbering over 200,000 individuals Pigeon nest here each summer. Throughout the year, six species of marine mammals Guillemot breed or haul out on the islands. These islands are beside the cold California current which originates in Alaska and flows north to south, they are also surrounded Photo: © Brian O’Neil by waters of the Gulf of Farallons National Marine Sanctuary. Lying 28 miles west of San Francisco Bay the Refuge is on the western edge of the continental shelf. This area of Western gull the ocean plunges to 6,000 foot depths. Cold upwelling water brought from the depths as the wind blows surface water westward from the shoreline, and the California current flowing southward past the islands provides an ideal biological mixing zone along the continental shelf and around the San Francisco Bay area. Photos: © Brian O’Neil We stw ard Win ds Upwelling ent Mixing urr a C Deep rni lifo Ca Cold Water S N USGS Chart of seafloor Upwelling occurs notably in the spring depths around when these wind and water currents Farallon NWR work together and saturate ocean waters with nutrients brought up from Black the deep ocean.
    [Show full text]
  • Visitors Map
    VISITORS MAP Explore Paso Robles Backroads TheOriginalRoadTrip.com VISITORS MAP Discover Wineries and vineyards Monterey Bay Carmel-by-the-Sea Alma Rosa Winery Wine Tasting 181-C Industrial Way Wine REGION Enjoy our local wines at Buellton 93427 16 tasting rooms – all walkable 805.688.9090 CarmelCalifornia.com/wine AlmaRosaWinery.com Hit the trail – the wine trail. California’s Central Coast is a Eden Rift Ampelos Cellars dream destination for wine lovers, with more than a dozen 10034 Cienega Rd. 312 N. 9th St. Hollister 95023 Lompoc 93436 American Viticultural Areas, or AVAs, producing some of 831.636.1991 805.736.9957 REGION REGION EdenRift.com AmpelosCellars.net California’s most popular wines. Choose among hundreds Elephant Seals, San Simeon Manzoni Cellars Brick Barn Wine Estate of Central Coast wineries to sample California wines Wine Tasting Room 795 W. Hwy. 246 Hampton Court on 7th Ave., Buellton 93427 including Pinot Noir, Chardonnay, and Zinfandel. With its btw San Carlos & Dolores St. 805.686.1208 Explore California’s Central Coast TRAVEL WELL endless variety, the Central Coast is California wine county Carmel by the Sea 93921 BrickBarnWineEstate.com Discover Harvey Bear 831.620.6541 monterey baY monterey baY you can visit again and again. ManzoniWines.com barbarA santa Ranch County Park Explore 350 miles of the world’s most beautiful coastline • Be an altruistic traveler by visiting Welcome Centers, Wineries of Santa Clara Valley Award-winning, meet the Vintner between San Francisco and Los Angeles. supporting the preservation of every destination, staying Enjoy hiking, biking, scenery 408.842.6436 on designated paths, and respecting others and wildlife.
    [Show full text]
  • National Conservation Lands
    ^ BUREAU OF LAND MANAGEMENT National Conservation Lands The Bureau of Land Management’s (BLM) system of National Conservation Lands includes more than 34 million acres of nationally significant landscapes with outstanding historic, cultural, ecological, and scientific values. Congress and presidents have provided specific designations to these lands to conserve, protect, and restore them for the benefit of Pompeys Pillar National Monument in Montana current and future generations. PHOTO BY ANN BOUCHER/BUREAU OF LAND MANAGEMENT National Conservation Lands The National Conservation Lands FY 2020 Appropriations Request system include BLM lands with the following congressional and presidential Please support $45 million for the Bureau of Land Management’s designations: National Conservation Lands in the FY 2020 Interior • National Monuments Appropriations bill, as well as robust funding for Wild and Scenic • National Historic Trails Rivers, National Scenic and Historic Trails, and Components • National Scenic Trails of National Conservation Lands that are part of Oregon and • Wild and Scenic Rivers California Grant Lands. • Wilderness Areas • Wilderness Study Areas APPROPRIATIONS BILL: Interior, Environment, and Related Agencies • National Conservation Areas AGENCY: Bureau of Land Management • Additional areas designated by ACCOUNT: Management of Lands and Resources Congress for inclusion in the system ACTIVITY: National Landscape Conservation System (National Conservation Lands) Background BLM created the National Landscape Recent Funding
    [Show full text]
  • CLASSIFICATION of CALIFORNIA ESTUARIES BASED on NATURAL CLOSURE PATTERNS: TEMPLATES for RESTORATION and MANAGEMENT Revised
    CLASSIFICATION OF CALIFORNIA ESTUARIES BASED ON NATURAL CLOSURE PATTERNS: TEMPLATES FOR RESTORATION AND MANAGEMENT Revised David K. Jacobs Eric D. Stein Travis Longcore Technical Report 619.a - August 2011 Classification of California Estuaries Based on Natural Closure Patterns: Templates for Restoration and Management David K. Jacobs1, Eric D. Stein2, and Travis Longcore3 1UCLA Department of Ecology and Evolutionary Biology 2Southern California Coastal Water Research Project 3University of Southern California - Spatial Sciences Institute August 2010 Revised August 2011 Technical Report 619.a ABSTRACT Determining the appropriate design template is critical to coastal wetland restoration. In seasonally wet and semi-arid regions of the world coastal wetlands tend to close off from the sea seasonally or episodically, and decisions regarding estuarine mouth closure have far reaching implications for cost, management, and ultimate success of coastal wetland restoration. In the past restoration planners relied on an incomplete understanding of the factors that influence estuarine mouth closure. Consequently, templates from other climatic/physiographic regions are often inappropriately applied. The first step to addressing this issue is to develop a classification system based on an understanding of the processes that formed the estuaries and thus define their pre-development structure. Here we propose a new classification system for California estuaries based on the geomorphic history and the dominant physical processes that govern the formation of the estuary space or volume. It is distinct from previous estuary closure models, which focused primarily on the relationship between estuary size and tidal prism in constraining closure. This classification system uses geologic origin, exposure to littoral process, watershed size and runoff characteristics as the basis of a conceptual model that predicts likely frequency and duration of closure of the estuary mouth.
    [Show full text]
  • Park Report Part 1
    Alcatraz Island Golden Gate National Recreation Area Physical History PRE-EUROPEAN (Pre-1776) Before Europeans settled in San Francisco, the area was inhabited by Native American groups including the Miwok, in the area north of San Francisco Bay (today’s Marin County), and the Ohlone, in the area south of San Francisco Bay (today’s San Francisco peninsula). Then, as today, Alcatraz had a harsh environment –strong winds, fog, a lack of a fresh water source (other than rain or fog), rocky terrain –and there was only sparse vegetation, mainly grasses. These conditions were not conducive to living on the island. These groups may have used the island for a fishing station or they may have visited it to gather seabird eggs since the island did provide a suitable habitat for colonies of seabirds. However, the Miwok and Ohlone do not appear to have lived on Alcatraz or to have visibly altered its landscape, and no prehistoric archeological sites have been identified on the island. (Thomson 1979: 2, Delgado et al. 1991: 8, and Hart 1996: 4). SPANISH AND MEXICAN PERIOD (1776-1846) Early Spanish explorers into Alta California encountered the San Francisco Bay and its islands. (Jose Francisco Ortega saw the bay during his scouting for Gaspar de Portola’s 1769 expedition, and Pedro Fages described the three major islands –Angel, Alcatraz, and Yerba Buena –in his journal from the subsequent 1772 expedition.) However, the first Europeans to record their visit to Alcatraz were aboard the Spanish ship San Carlos, commanded by Juan Manuel de Ayala that sailed through the Golden Gate and anchored off Angel Island in August 1775.
    [Show full text]