Biodiversity Guide - The Intertwine

egional conservation strategybiodiversity guideAppendix I Watershedswidespread in westernOregon, western pearlshellsare considered avulnerable species andtheir conservation isclosely linked to thatof salmon.Other sensitivespecies present includelong-toed, northwestern,and Columbia salamanders,red-leggedfrogs, and paintedturtles. The East Buttesand forested tributaryheadwaters provideupland and streamsidehabitat for residentand migratory birds,including Pacific-slopeand willow flycatchers;western wood-pewees;golden-crowned kinglets; Bewick’s and winterwrens; orange-crowned, Wilson’s, and Townsend’swarblers; and Swainson thrushes. The JohnsonCreek mainstem and its many tributaries act astravel corridors and connect habitat for birds,black-tailed deer, coyote, river otter, and beaver.The East Buttes provide important habitat andconnectivity for elk, and the Johnson Creek mainstemis probably the most important east-westbiodiversity corridor in the southern portion ofthe Portland metropolitan region.There currently are about 4,600 acres of parksand open space in the watershed. including nearly900 acres acquired since 1995. Inside the Cityof Portland boundary, more than 1,000 acresare designated as special habitat areas, meaningthat they provide especially important fish andwildlife habitat values and functions. Importanthabitat types still present in the watershed includebottomland hardwood forest, wetland complexes(one of the largest being 19-acre Beggars Tickmarsh), and upland prairie and grasslands. Thereis protected forested upland habitat on PowellButte, Clatsop Butte, Gabbert Hill, and variousother volcanic buttes.Some of the most extensive streamside foreston Johnson Creek is in the middle watershed. Forexample, Reach 16, upstream of Regner Road inGresham, has an intact riparian forest canopy,as does the riparian corridor between PowellButte and Leach Botanical Garden. The headwaterstreams flowing through rural and agriculturallands in the upper watershed have verylittle riparian vegetation. Some of the tributaryheadwaters remain well forested (e.g., Upper KelleyCreek and Upper Mitchell Creek). The lowerwatershed generally suffers from a lack of riparianvegetation. Notable exceptions include JohnsonCreek’s confluence with the Willamette River andTideman Johnson Natural Area.Based on Ecosystem Diagnosis and Treatment(EDT) modeling for coho salmon, priorities forcore instream and riparian habitat protectioninclude Reach 16 of Johnson Creek, lower HoganCreek, upper and lower Kelley Creek, and upperMitchell Creek. Priority areas for restoration areReaches 4 and 5 of Johnson Creek (i.e., Tideman-Johnson), Reach 15 of Johnson Creek, UpperCrystal Springs, Errol Creek, middle KelleyCreek, lower Mitchell and Sunshine creeks, andBadger Creek. The next step for salmon habitatrecovery is to connect core habitat areas, whichinclude Reaches 1, 2, 6, 7, 8, 9, 10, and 17 ofJohnson Creek.Conservation and restoration efforts shouldfocus on areas that increase riparian connectivityand provide wildlife travel corridors. One ofthe challenges will be to maintain ecological andhydrological function as areas in the middle andupper watershed (notably the Pleasant Valleyand Springwater planning areas and the City ofDamascus) develop in the coming years.As noted above, much of Johnson Creek hasbeen channelized and disconnected from itshistorical floodplain. Off-channel habitat remainsrare on Johnson Creek, in spite of recent projectsthat have reconnected the creek to its floodplain(notably at Tideman-Johnson Natural Area, theconfluence of Errol Creek and Johnson Creek, theJohnson Creek mainstem south of Powell Butte,and Kelley Creek’s confluence with JohnsonCreek). In addition, large woody debris is severelylacking throughout Johnson Creek.The Oregon Department of EnvironmentalQuality rated water quality in Johnson Creek aspoor. Water quality issues include bacteria, hightemperatures, and toxic legacy pesticides suchas DDT, primarily originating in the agriculturalupper watershed and brought into the creek byeroding soils.There are several known invasive weed speciesin the watershed, including Japanese knotweed(more than 90 percent controlled as of 2010),false-brome, garlic mustard, and regionally ubiquitousinvasive species such as reed canarygrass,English and Irish ivy, and Himalayan blackberry.The following are high-priority conservationor restoration actions in this watershed:n Non-point source pollution reductionn Low-impact development in middle and upperwatershedn Stormwater retrofitting in existingdevelopmentn Private lands restoration and conservationn Continued streamside forest restorationCurrent Major Initiatives —Johnson Creek Watershedn Watershed-wide riparian invasive weed removaland native species revegetation (ongoing)n Removal of eight partial fish passage barrierson Crystal Springs Creekn Floodplain reconnection /off-channel rearingand refuge habitat (several large projects havebeen completed; several more programmed)n Instream and floodplain large wood installationat Johnson Creek/Willamette River confluenceOrganizations and Partners —Johnson Creek Watershedn Johnson Creek Watershed Council –Matt Clarkn City of Damascus – Dan O’Delln City of Milwaukie – JoAnn Herrigeln City of Portland – Maggie Skenderian (Bureauof Environmental Services), Lynn Barlow (PortlandParks and Recreation)n City of Gresham – Steve Fanchern Clackamas Water Environment Services –John Nagyn North Clackamas Parks and Recreation –Tonia Burnsn Multnomah County – Roy Iwain East Multnomah Soil and Water ConservationDistrict – Jean Fiken Clackamas County Soil and WaterConservation District – Tom Salzern Johnson Creek Conservation Partnership (agroup of nonprofits and jurisdictions focused onacquisition of conservation land)n Backyard Habitat Certification Program /JohnsonCreek pilot (Johnson Creek Watershed Council,Portland Audubon, Columbia Land Trust)n Crystal Springs Community Collaborative –Rowan Steele, City of Portlandn SOLV – Sara Ryann Friends of Trees – Logan Lauvrayn Reed College – Zac Perryn Johnson Creek Interjurisdictional Committee(focus on watershed monitoring)n Xerces Society /Johnson Creek WatershedCouncil – Freshwater mussel sampling274 275