The Historical Ecology of the Tijuana Estuary & River Valley (Restore America's Estuaries 2018 Conference Presentation)

The Historical Ecology of the Tijuana Estuary & River Valley Sam Safran San Francisco Estuary Institute Long Beach, CA  December 12, 2018 Restore America’s Estuaries Co-authors: Sean Baumgarten, Erin Beller, Danielle Bram, Jeff Crooks, Shawna Dark, Robin Grossinger, Travis Longcore, Julio Lorda, Eric Stein Funded by: The California State Coastal Conservancy courtesy Coronado Public Library courtesy Coronado Public Library courtesy Coronado Public Library courtesy Coronado Public Library courtesy Coronado Public Library Remarking the boundary, ca. 1894 IBC 1898, courtesy University of North Texas Mendenhall 1905, courtesy USGS Botanizing on Mesa, 1905 Travelling to Mexico, ca. 1890 Historical Ecology Using the past to understand the present landscape and envision its future potential •Not about recreating the past! • Understand ecological and physical patterns/process that shaped the landscape • Not just the “way things were,” but the “way things work” Streams and estuaries reconstructed Sacramento-San Joaquin Delta Napa River Mark West Creek SF Baylands South Coast estuaries Marsh Creek Alameda Creek Penitencia Creek Coyote Creek Guadalupe River Uvas Creek Llagas Creek Pajaro River Salinas River Ventura River Santa Clara River Ballona Creek San Gabriel River Tijuana River Streams and estuaries reconstructed Sacramento-San Joaquin Delta Napa River Mark West Creek SF Baylands South Coast estuaries Marsh Creek Alameda Creek Penitencia Creek Coyote Creek Guadalupe River Uvas Creek Llagas Creek Pajaro River Salinas River Ventura River Santa Clara River Ballona Creek San Gabriel River Tijuana River Tijuana River watershed lower Tijuana River Valley 1,750 sq. mi. 16.4 sq. mi. Methods Collect archival data Methods Collect archival data Extract relevant information Methods Collect archival data Extract relevant information Overlay, synthesize Methods Collect archival data Extract relevant information Overlay, synthesize Create map (and other products) Historical conditions: Tijuana River Valley, ca. 1850 1 km Dune River channel Beach River wash / Riparian scrub Subtidal water Grassland / Coastal sage scrub Mud flat / Sand flat Perennial freshwater wetland Salt flat / Open water Pond Salt marsh Vernal pool Alkali meadow complex / H lex / High marsh transition zone River channel Temporary stream Riparian forest Historical conditions: Tijuana River Valley, ca. 1850 Salt marsh/mudflatdominated estuary 1 km Dune River channel Beach River wash / Riparian scrub Subtidal water Grassland / Coastal sage scrub Mud flat / Sand flat Perennial freshwater wetland Salt flat / Open water Pond Salt marsh Vernal pool Alkali meadow complex / H lex / High marsh transition zone River channel Temporary stream Riparian forest Historical conditions: Tijuana River Valley, ca. 1850 Salt marsh/mudflatdominated estuary 1 km Dune River channel Beach River wash / Riparian scrub Subtidal water Grassland / Coastal sage scrub Mud flat / Sand flat Perennial freshwater wetland Salt flat / Open water Pond Salt marsh Vernal pool Alkali meadow complex / H lex / High marsh transition zone River channel Temporary stream Riparian forest Broad river corridor with (mostly) intermittent flow and riparian scrub Historical conditions: Tijuana River Valley, ca. 1850 Seasonal wetlands on valley bottom Salt marsh/mudflatdominated estuary 1 km Dune River channel Beach River wash / Riparian scrub Subtidal water Grassland / Coastal sage scrub Mud flat / Sand flat Perennial freshwater wetland Salt flat / Open water Pond Salt marsh Vernal pool Alkali meadow complex / H lex / High marsh transition zone River channel Temporary stream Riparian forest Broad river corridor with (mostly) intermittent flow and riparian scrub Grassland/coastal scrub with wetlands on tablelands and in canyons Historical conditions: Tijuana River Valley, ca. 1850 Seasonal wetlands on valley bottom Salt marsh/mudflatdominated estuary 1 km Dune River channel Beach River wash / Riparian scrub Subtidal water Grassland / Coastal sage scrub Mud flat / Sand flat Perennial freshwater wetland Salt flat / Open water Pond Salt marsh Vernal pool Alkali meadow complex / H lex / High marsh transition zone River channel Temporary stream Riparian forest Broad river corridor with (mostly) intermittent flow and riparian scrub Key messages for today 1 The valley supported a diverse array of wetlands in a dry climate. Key messages for today 1 The valley supported a diverse array of wetlands in a dry climate. 2 Floods maintained a large and dynamic river corridor. Key messages for today 1 The valley supported a diverse array of wetlands in a dry climate. 2 Floods maintained a large and dynamic river corridor. Management implications of these changes Key messages for today 1 The valley supported a diverse array of wetlands in a dry climate. 2 Floods maintained a large and dynamic river corridor. Management implications of these changes 1 km Dune River channel Beach River wash / Riparian scrub Subtidal water Grassland / Coastal sage scrub Mud flat / Sand flat Perennial freshwater wetland Salt flat / Open water Pond Salt marsh Vernal pool Alkali meadow complex / H lex / High marsh transition zone River channel Temporary stream Riparian forest drylands wetlands 1 km ~75% wetland habitat types Estuarine wetlands 1 km N USA Dune River channel Beach River wash / Riparian scrub Subtidal water Grassland / Coastal sage scrub Mud flat / Sand flat Perennial freshwater wetland Salt flat / Open water Pond Salt marsh Vernal pool Alkali meadow complex / H lex / High marsh transition zone River channel Temporary stream Riparian forest Estuarine wetlands 80 ha (200 acres) of intertidal flats • 21 km of tidal channels • at least double today’s area 1 km N US Coast Survey 1852 Estuarine wetlands 80 ha (200 acres) of intertidal flats • 21 km of tidal channels • at least double today’s area 250 ha (600 ac) of salt marsh • 10% of all vegetated estuarine wetlands in SoCal • 75% more than today 1 km N US Coast Survey 1852 Estuarine wetlands • Salt marsh loss concentrated in southern part of the estuary • Thought to be driven by local sedimentation and associated decrease in tidal prism (minus 55-85%) 250 ha (600 ac) of salt marsh • 10% of all vegetated estuarine wetlands in SoCal • 75% more than today Management implications • Supports continued efforts to restore intertidal habitat and increase tidal prism • Highlights future management concern (will sediment become more of a resource as SLR accelerates?) US Coast Survey 1852 Estuarine wetlands Gray 1849 Courtesy Coronado Public Library Coast Survey 1852 Courtesy Coronado Public Library 17 ha (40 ac) of salt flat Gray 1849 Courtesy Coronado Public Library US Coast Survey 1852 Alkali meadow complex / High marsh transition zone 1 km N USA 1896: “Salt grass meadows of Tia Juana valley” – Pacific Rural Press 1896 Dune River wash / Riparian scrub Beach Grassland / Coastal sage scrub Subtidal water Perennial freshwater wetland Mud flat / Sand flat Pond Salt flat / Open water Vernal pool Salt marsh Riparian forest Alkali meadow complex / High marsh transition zone River channel Alkali meadow complex / High Marsh Transition Zone Wandering skipper (Panoquina errans) • candidate for listing under ESA • host plant is salt grass • today considered to be restricted to salt marshes… … but possible this species once also thrived further inland. ca. 1850 ca. 2012 Alkali meadow complex / High Marsh Transition Zone ca. 1850 • Loss associated with conversion to more xeric grass/scrub habitats (not development) • Likely driven by early groundwater declines ca. 2012 Alkali meadow complex / High Marsh Transition Zone ca. 1850 • Loss associated with conversion to more xeric grass/scrub habitats (not development) • Likely driven by early groundwater declines • Groundwater levels have rebounded • Can we recover “missing” wetlands and associated functions? ca. 2012 River wash & Riparian scrub 1 km N USA Dune River wash / Riparian scrub Beach Grassland / Coastal sage scrub Subtidal water Perennial freshwater wetland Mud flat / Sand flat Pond Salt flat / Open water Vernal pool Salt marsh Riparian forest Alkali meadow complex / High marsh transition zone River channel “monte de saus” River wash & Riparian scrub “Arroyo Tijuan” “monte de saus” USDC ca. 1840 Courtesy Bancroft Library 1 km N USA Dune River wash / Riparian scrub Beach Grassland / Coastal sage scrub Subtidal water Perennial freshwater wetland Mud flat / Sand flat Pond Salt flat / Open water Vernal pool Salt marsh Riparian forest Alkali meadow complex / High marsh transition zone River channel Primarily willow scrub, but broad range of species Common Name Trees Latin Name sandbar willow Salix exigua Goodding’s willow red willow arroyo willow cottonwood California sycamore Shrubs S. gooddingii S. laevigata S. lasiolepis Populus sp. Platanus racemosa mulefat Baccharis salicifolia black sage white sage common sagebrush arrowweed Bush senecio fourwing saltbush chaparral mallow Salvia mellifera S. apiana Artemisia tridentata Pluchea sericea Senecio douglasii Atriplex canescens Malacothamnus fasciculatus northwest willow California fagonia blue elderberry Salix sessilifolia Fagonia laevis Sambucus nigra subsp. caerulea Species indicative of wetter zones (obligate and rigid bird’s beak facultative wetland species) Herbs nightshade clematis branching phacelia Chinese parsley rigid bird’s beak bladderpod skunkbush Solanum sp. Clematis ligusticifolia Phacelia ramosissima Heliotropium curassavicum Cordylanthus rigidus Peritoma arborea Navarretia squarrosa Matilija poppy Romneya coulteri “rare” (Harwood) California evening primrose Oenothera californica spiny rush Juncus acutus southwestern spiny rush Juncus acutus subsp. leopoldi “abundant” California croton Croton californicus Heermann’s lotus Acmispon heermannii “common” Nuttall’s lotus Lotus nuttallianus “common” Beardless wild rye Elymus triticoides “rare” spiny goldenbush/ spiny chloracantha Chloracantha spinosa, C. spinosa var. spinosa bush seepweed Suaeda nigra slender woolly-heads Nemacaulis denudata var. gracilis “banks of Tia Juana River” (Brandegee) scarlet lupine Lupinus concinnus California sealavender Limonium californicum Indian hemp Apocynum cannabinum mugwort Artemisia douglasiana wide throated yellow monkeyflower Mimulus brevipes volcanic gilia Gilia ochroleuca ssp. Exilis ropevine clematis Clematis pauciflora “common” “common” “rare” “common” “common” “common” “common” “edges of dried streams near Southern point San Diego Bay”; “abundant in the Tia Juana River bed. It is Records from 1849-1949 “co “co “rar “co “co “co “co “ed Bay “Tia “Tia Primarily willow scrub, but broad range of species Common Name Trees Latin Name sandbar willow Salix exigua Goodding’s willow red willow arroyo willow cottonwood California sycamore Shrubs S. gooddingii S. laevigata S. lasiolepis Populus sp. Platanus racemosa mulefat Baccharis salicifolia black sage white sage common sagebrush arrowweed Bush senecio fourwing saltbush chaparral mallow Salvia mellifera S. apiana Artemisia tridentata Pluchea sericea Senecio douglasii Atriplex canescens Malacothamnus fasciculatus northwest willow California fagonia blue elderberry Salix sessilifolia Fagonia laevis Sambucus nigra subsp. caerulea Species indicative of wetter zones (obligate and rigid bird’s beak facultative wetland species) Species indicative of drier zones (sage scrub species, generally more xeric) Herbs nightshade clematis branching phacelia Chinese parsley rigid bird’s beak bladderpod skunkbush Solanum sp. Clematis ligusticifolia Phacelia ramosissima Heliotropium curassavicum Cordylanthus rigidus Peritoma arborea Navarretia squarrosa Matilija poppy Romneya coulteri “rare” (Harwood) California evening primrose Oenothera californica spiny rush Juncus acutus southwestern spiny rush Juncus acutus subsp. leopoldi “abundant” California croton Croton californicus Heermann’s lotus Acmispon heermannii “common” Nuttall’s lotus Lotus nuttallianus “common” Beardless wild rye Elymus triticoides “rare” spiny goldenbush/ spiny chloracantha Chloracantha spinosa, C. spinosa var. spinosa bush seepweed Suaeda nigra slender woolly-heads Nemacaulis denudata var. gracilis “banks of Tia Juana River” (Brandegee) scarlet lupine Lupinus concinnus California sealavender Limonium californicum Indian hemp Apocynum cannabinum mugwort Artemisia douglasiana wide throated yellow monkeyflower Mimulus brevipes volcanic gilia Gilia ochroleuca ssp. Exilis ropevine clematis Clematis pauciflora “common” “common” “rare” “common” “common” “common” “common” “edges of dried streams near Southern point San Diego Bay”; “abundant in the Tia Juana River bed. It is Records from 1849-1949 “co “co “rar “co “co “co “co “ed Bay “Tia “Tia Dry-season conditions: areas without surface water areas with surface water 1 mi 1 km Intermittent river; limited locations with perennial surface water Sept 1869: “dry bed of TJ river” September 1869: “bed of river dry” September 1869: “bed of river dry” Dry-season conditions: areas without surface water areas with surface water September 1869: “dry bed of ravine” June 1854: “in dry time sink in sand” July 1903: “waterless Tia Juana River” May 1928: surface flow disappears July 1937: “river near the 1849: boundary ceased flowing” above this point… “dry Sept 1869: “dry during the bed of creek” greatest portion of the year” Intermittent river; limited locations with perennial surface water 1 mi 1 km Sept 1889: “spring” Dry-season conditions: areas without surface water areas with surface water 1 mi 1 km Summer 1931: “Potholes” with water Sept. 1869: “running water” Agua Caliente hot springs “agua permanente” May 1769: “stream running with a good sized flow of water that… issues up out of the ground” [location very approximate] Jan 1910: river “water for some months to come” in Matanuco Cnyn. July 1920: surface flow in photos Intermittent river; limited locations with perennial surface water Sept 1889: “spring” Dry-season conditions: areas without surface water areas with surface water 1 mi 1 km Summer 1931: “Potholes” with water Sept. 1869: “running water” Agua Caliente hot springs “agua permanente” May 1769: “stream running with a good sized flow of water that… issues up out of the ground” [location very approximate] Jan 1910: river “water for some months to come” in Matanuco Cnyn. July 1920: surface flow in photos Intermittent river; limited locations with perennial surface water Perennial wetlands within the river corridor courtesy Archivo Histórico del Agua Key messages for today 1 The valley supported a diverse array of wetlands in a dry climate. 2 Floods maintained a large and dynamic river corridor. Key messages for today 1 The valley supported a diverse array of wetlands in a dry climate. 2 Floods maintained a large and dynamic river corridor. Periodic floods inundated most of the valley 1918, courtesy SDHC 1918, courtesy SDHC 80,000 70,000 60,000 100-yr flood 50,000 estimated discharge 40,000 50-yr 30,000 20,000 measured discharge 10-yr 10,000 2000 1990 1980 1970 1960 1950 1940 1930 1920 1910 1900 1890 0 1880 Annual Peak Discharge (cfs) 1921, courtesy Sociedad de Historia de Tijuana Floods drove river movement May 1941 (after sizeable floods in February, March, and April) Erickson 1941, courtesy SDHC Floods drove river movement May 1941 (after sizeable floods in February, March, and April) Erickson 1941, courtesy SDHC Floods drove river movement May 1941 (after sizeable floods in February, March, and April) Erickson 1941, courtesy SDHC Floods drove river movement May 1941 (after sizeable floods in February, March, and April) Erickson 1941, courtesy SDHC Floods drove river movement May 1941 (after sizeable floods in February, March, and April) Erickson 1941, courtesy SDHC Historical courses of the Tijuana River 1 850 1 889 1 894 1 904 1 921 1 928 1 943 1 967 1 980 1 989 201 2 basemap: NAIP 2014 Historical courses of the Tijuana River 1 850 1 889 1 894 1 904 1 921 1 928 1 943 1 967 1 980 1 989 201 2 • Nearly all 10-year flood events have caused major channel movement basemap: NAIP 2014 • Most smaller events do not. 1 850 Historical courses of the Tijuana River 1 889 1 894 • River movement is a natural, relatively-frequent process 1 904 1 921 1 928 1 943 1 967 1 980 1 989 201 2 • Nearly all 10-year flood events have caused major channel movement basemap: NAIP 2014 • Most smaller events do not. Floods created habitat variability Erickson 1941, courtesy SDHC Floods created habitat variability Erickson 1941, courtesy SDHC Floods created habitat variability “After I entered the field, small open spaces of alluvial river-bottom sand were encountered that make an ideal situation for pocket mice” - Erickson 1941, courtesy SDHC Jack von Bloeker July 1931 Floods created habitat variability “After I entered the field, small open spaces of alluvial river-bottom sand were encountered that make an ideal situation for pocket mice” - Jack von Bloeker July 1931 “In the summer…all that remains of the water…is found in depressions excavated by the current. Western pond turtles were quite abundant.” - Robert Harwood August 1931 Erickson 1941, courtesy SDHC Floods created habitat variability • River movement is a natural, relatively-frequent process… • …that helps maintain habitat heterogeneity and biodiversity • Could be both practical and beneficial to allow for this movement “After I entered the field, small open spaces of alluvial river-bottom sand were encountered that make an ideal situation for pocket mice” - Jack von Bloeker July 1931 “In the summer…all that remains of the water…is found in depressions excavated by the current. Western pond turtles were quite abundant.” - Robert Harwood August 1931 Erickson 1941, courtesy SDHC Key messages for today 1 The valley supported a diverse array of wetlands in a dry climate. 2 Floods maintained a large and dynamic river corridor. Management implications of these changes Final thought THANK YOU. sams@sfei.org www.sfei.org/projects/tijuana Funder California State Coastal Conservancy Greg Gauthier (Contract Manager) Team Robin Grossinger (SFEI) Erin Beller (SFEI) Sean Baumgarten (SFEI) Sam Safran (SFEI) Shawna Dark (CSU Northridge) Danielle Bram (CSU Northridge) Travis Longcore (USC) Eric Stein (SCCWRP) Jeff Crooks (TRNERR) Julio Lorda (TRNERR) Technical Advisors Brian Bledsoe (Colorado State) Jeff Haltiner (ESA) Dave Jacobs (UCLA) John Largier (UC Davis) Lina Ojeda (COLEF) Bruce Orr (Stillwater Sciences) Ellen Wohl (Colorado State) Richard Wright (San Diego State) Joy Zedler (UW-Madison)