Escondido Creek Conservation Parcels Bird Survey Report. prepared for San Elijo Lagoon Conservancy. by Maryanne Bache.

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1 Escondido Creek Conservation Parcels Bird Survey Report prepared for San Elijo Lagoon Conservancy by Maryanne Bache August 3, 2009 INTRODUCTION This report summarizes the results of a bird monitoring study conducted along Escondido Creek from November 2008 to June 2009 on conservation parcels owned by San Elijo Lagoon Conservancy. The objective of this initial study was to determine avian species presence as a biological parameter of a baseline assessment of conservation parcels. To accomplish that, a standardized bird monitoring protocol was developed that could be used for future surveys and assessments. There are many reasons that bird monitoring is adopted as a basic component of long-term stewardship in conservation areas with significant riparian habitats. Birds are highly visible, diverse, diurnal and therefore cost effective to monitor. Many migrants and year round birds are dependent on riparian habitats. Consequently, they are good indicators of the health of an ecosystem. As secondary consumers, birds are sensitive indicators of environmental change. By managing for a diversity of birds most other elements of biodiversity are assured. Riparian habitats are important to ecosystem integrity and function. They provide important breeding grounds, over wintering and migration stopovers and corridors for dispersal for many bird species. Despite their importance, riparian habitat has been decimated over the past 150 years and now covers less than 2% to 15% of its historic range regionally. Due to their biological wealth and severe degradation riparian areas are the most critical habitat for conservation of migrant and resident birds in the West (RHJV, 2004). Transect bird surveys have been conducted monthly in the San Elijo Lagoon Ecological Reserve downstream of the Escondido Creek parcels for over 10 years by Robert Patton. The accumulated data is a valuable record of avian species richness and diversity. Because of the

2 popularity of birdwatching and the high level of sophistication of many amateur birdwatchers there is a great potential for public participation in bird monitoring. This is evident in the steady number of volunteers who contribute to the monthly counts in the reserve. The sustained and serious interest so many people show for birds has unquestionably heightened the awareness of land stewardship needs. STUDY SITE The study site is comprised of contiguous conservation parcels located along a one mile stretch of Escondido Creek in northern San Diego County, California (see map). Escondido Creek, extending from Lake Dixon to the mouth of the San Elijo Lagoon, is home to a wide range of riparian habitats and many species of breeding birds. The creek in the study site location supports a willow dominant riparian habitat infiltrated by non-native invasive plants including eucalyptus. The creek s influence varies in width from a narrow ravine of approximately 40 meters to a broader floodplain of 400 meters across. It is bordered on both sides by private residences and horse facilities. METHOD There are numerous field data collection methods for documenting birds in a particular area. In this case a point count method was chosen due to three limiting factors: (1) establishing a year round walking transect through the riparian corridor was prevented by conservation measures in place; (2) the creek is in a flood plain and seasonally saturated, limiting a walking transect; and (3) the conservation parcels are surrounded by private property with no public access. Avian point count monitoring is a quantitative assessment involving repeated measures at regular intervals at fixed locations to establish a baseline measure of bird diversity. Carried out in its most basic form it is a tally of all birds seen or heard for a given time at a given location. Point counts can detect the relative abundance of many species over broad areas from discrete locations. The given time period allows quick and accurate accounts of all birds seen and heard. This can be accomplished most effectively by one to two trained monitors. Over time (3-5 years) bird abundance and richness can be assessed. Monitoring for population trends needs a much longer time commitment, requiring 5 to 10 years or more of continuous sampling depending on what is being measured and the desired level of accuracy. Nine point count stations averaging 200meters apart along a one mile riparian corridor adjacent to Escondido Creek were identified and mapped (Table 1).

3 Table 1: Escondido Creek Point Count Stations Number Name Address/location GPS coordinates 1 Potluck Berm north th St. N W Potluck Berm south N W Estes 4580 El Mirlo N W La Bajada south White Gate N W Pond/rookery Queen's SW corner N W Ford Reserve Manchester gate N W MacConnel's north 4098 Manchester Ave N W MacConnel's sewer cover N W MacConnel's south creekside/canoe N W Permission to access the stations on private parcels was obtained from property owners prior to surveying. All count stations were surveyed monthly during the winter and breeding seasons, November 2008 to June Number of visits: Visit timing: Weather guidelines: Station count time: Detection: Detections distance: Once a month to all stations on the same day starting in the early morning; visits 4 weeks apart. 4 visits in the winter season (Nov. Feb.) and 4 in the breeding season (Mar. Jun.) Do not survey in rain, cold drizzle, heavy fog or wind > 15mph 10 minute count; begin recording after a one minute settle down period, adjusting for human/dog disturbances. Flyover birds and juvenile birds recorded; no sound recordings used 0 to 50 meters; >50 meters; overhead (see data form)

4 RESULTS Overall 69 bird species were detected on the monthly surveys between November 2008 and June 2009 along the one mile stretch of Escondido Creek (Table 2). Table 2: Monthly Species Counts Survey Date 11/19/08 12/18/08 1/21/09 2/18/09 3/18/09 4/15/09 5/22/09 6/19/09 Total SPECIES Gadwall Mallard Pied-billed Grebe Great Blue Heron Great Egret Snowy Egret 3 3 Black-cr. Night-Heron 1 1 White-faced Ibis White-tailed Kite 1 1* 2* Sharp-shinned Hawk 1 1 Cooper's Hawk 1* 0 Red-shouldered Hawk 1* Red-tailed Hawk * American Kestrel 1 1 1* Clapper Rail Virginia Rail Semipalmated Plover 2 2 Killdeer Lesser Yellowlegs 2 2 Least Sandpiper 1 1 Wilson's Snipe 1 1 Rock Dove 10* 0 Mourning Dove White-throated Swift Anna's Hummingbird Selasphorus sp Nuttall's Woodpecker Downy Woodpecker Black Phoebe Say's Phoebe Cassin's Kingbird Western Kingbird 1 1 Least Bell's Vireo Hutton's Vireo 1 1 Western Scrub Jay 1 1 American Crow 6* Common Raven 1* 3* 0 Tree Swallow 1 1 Cliff Swallow Bushtit Bewick's Wren House Wren Marsh Wren

5 Ruby-crowned Kinglet Western Bluebird Wrentit Northern Mockingbird European Starling 13* American Pipit Orange-cr. Warbler Yellow Warbler Yellow-rumped Warbler Common Yellowthroat Yellow-breasted Chat Spotted Towhee California Towhee Song Sparrow White-crowned Sparrow Black-headed Grosbeak Red-winged Blackbird Brewer's Blackbird 1 1 Great-tailed Grackle 1 1 Brown-headed Cowbird Hooded Oriole House Finch Lesser Goldfinch American Goldfinch House Sparrow 3 3 TOTALS * = Birds detected greater than 50 meters from the count station and high flyovers are noted but not counted. Species richness, or the number of species detected per count varied between count stations and seasons. The average number of species detected per month was 34, with a low of 23 species in November 08 and a high of 41 in April 09. Vegetative canopy structure and cover, percentage of invasive plant species, width of the creek, breadth of the flood plain, associated habitats, horse pastures, and human disturbances varied substantially at each count station. These factors undoubtedly influenced the number of birds detected. Count stations #1 and #2 showed the greatest species richness over the 8 surveys (Table 3).

6 Table 3: Species Richness is number of species detected per count Count Station Total^ Av.** Date Nov Dec Jan Feb Mar Apr May Jun Average* * = Average # of species detected at each station over 8 surveys = Overall average # of species detected per point count 34 = Average # of species detected per month 69 = Total number of species detected on all surveys ^ = Total # of species detected each month at all stations **= Average # of species detected at each station in that month Bird abundance, or the number of individuals detected per count, also varied between count stations and seasons. The average number of individuals detected per month was 382 with a low of 200 in November 08 and a high of 461 individuals in June 09 (Table 4). Table 4: Bird Abundance is number of individuals detected per count Count Station Total^^ Date Nov Dec Jan Feb Mar Apr May Jun Total^ Average* * = Average # of individuals detected per station over 8 surveys 382 = Overall average # of individuals detected per month = Average # of individuals detected per count ^ = Total # of individuals detected per station over 8 surveys ^^ = Total # of individuals detected per month at all stations

7 Breeding behavior was observed and recorded using codes employed on the San Diego County Bird Atlas (Unitt, 2004): nest building (NB), adult on nest (ON), presence of nestlings seen or heard (NN), adults feeding young or carrying food (FY), chicks seen or heard (CH), fledglings dependent on parents (FL), or juvenile birds (JV). Possible breeding was noted by the presence of singing males in suitable habitat during the breeding season (SM) or a pair together in suitable habitat during breeding season (PR). The data for each point count station with numbers of birds, species and breeding codes can be found in the Appendix. Table 5: Breeding Species Observed Common name Scientific Name Conservation Status Breeding Behaviors Great Blue Heron Ardea herodias CSC NB, ON, NN, FY Great Egret Ardea alba CSC NB, ON, NN, FY White-tailed Kite Elanus caeruleus CSC JV Virginia Rail Rallus limicola CH Light-footed Clapper Rail Rallus longirostris E PR Anna s Hummingbird Calypte anna NB, ON Black Phoebe Sayornis nigricans FY, FL Least Bell s Vireo Vireo bellii pusillus E FY, FL American Crow Corvus brachyrhynchos FY Bushtit Psaltriparus minimus NB, ON House Wren FL Marsh Wren Cistothorus palustris CSC NB, FY, FL clarkae Yellow Warbler Dendroica petechia CSC SM Common Yellowthroat FS FL Yellow-breasted Chat Icteria virens auticollis CSC SM California Towhee Pipilo crissalis JV Song Sparrow Melospiza melodia FS FY, FL Black-headed Grosbeak Pheucticus FS SM, PR melanocephalus Red-winged Blackbird Agelaius phoeniceus FY Brown-headed Cowbird Molothrus ater SM, PR House Finch Carpodacus mexicanus FY, FL Lesser Goldfinch Carduelis psaltria FY, FL E = endangered species, federal and state listed CSC = California Species of Special Concern FS = California Partners in Flight Riparian Conservation Focal Species (RHJV 2004)

8 DISCUSSION Of the 69 bird species recorded during the study, there is a subset of species that are riparian obligates. These species depend on intact riparian habitats for breeding success and as such have experienced drastic population declines as riparian and associated wetland habitats have degraded. Their presence and breeding status gives insight into the quality of the habitat. This initial baseline study will be useful in future examinations of bird response to changes in habitat and management of the conservation parcels. Species that have particular breeding requirements making them indicators of riparian habitat quality can be considered focal species. Those listed in the Riparian Bird Conservation Plan (RHJV, 2004) include but are not limited to: Black-headed Grosbeak, Common Yellowthroat, Least Bells Vireo, Song Sparrow, Yellow-breasted Chat, and Yellow Warbler. Marsh Wren, Light-footed Clapper Rail, White-tailed Kite, and Red-winged Blackbird, as well as the nesting locations of Great Blue Herons and Great Egrets are also important indicators of riparian associated habitats found in the study site. Of the 22 species that showed possible or confirmed breeding success, 12 of them are valuable indicators of habitat quality, riparian focal species (Table 6). Table 6: Riparian Focal Species Common name Scientific Name Conservation Breeding Behaviors Status Great Blue Heron Ardea herodias CSC NB, ON, NN, FY Great Egret Ardea alba CSC NB, ON, NN, FY White-tailed Kite Elanus caeruleus CSC JV Light-footed Clapper Rail Rallus longirostris E PR Least Bell s Vireo Vireo bellii pusillus E FY, FL Marsh Wren Cistothorus palustris CSC NB, FY, FL clarkae Yellow Warbler Dendroica petechia CSC SM Common Yellowthroat FS FL Yellow-breasted Chat Icteria virens auticollis CSC SM Song Sparrow Melospiza melodia FS FY, FL Black-headed Grosbeak Pheucticus FS SM, PR melanocephalus Red-winged Blackbird Agelaius phoeniceus FY E = endangered species, federal and state listed CSC = California Species of Special Concern FS = California Partners in Flight Riparian Conservation Focal Species (RHJV 2004) Of particular note, is the endangered Least Bells Vireo whose populations have been greatly reduced in much of its historical range. Nests are typically within one meter of the ground in dense vegetation preferably in early successional riparian zones. It is a common target of nest parasitism by Brown-headed Cowbirds. On May 22, 2009 successful breeding was documented at station #3 with the observation of two fledglings following an adult and being fed by the adult. It is encouraging in an area where cowbirds were present during three months of the breeding season surveys, April-June The young family attests to sufficient vegetative cover in at least one area of the one mile study site. Station #3 exhibits a broad and diverse canopy

9 including sycamores and willows and a significant vegetative understory. Dense cover near nests likely reduces the ability of cowbirds to locate vireo nests and may shield parental activity from the view of searching cowbirds (Kus, 2006). As land managers seek to understand the complex issues involved in making decisions about the physical parameters of conservation parcels, bird monitoring studies can shed light on the functional value of the landscape. Birds are sensitive indicators of environmental change due to their high metabolic rate, their relatively high position in the food chain and their distribution across a wide variety of habitats. Birds studies are relatively cost effective to conduct providing an excellent means by which to track changes in natural systems. REFERENCES Bibby, C. J., Burgers, N. D., and Hill, D. A Bird Census Techniques. British Trust for Ornithology. Academic Press. Kus, B. E Factors Influencing the Incidence of Cowbird Parasitism of Least Bell s Vireos. USGS Publication Brief for Resource Managers. Western Ecological Research Center. Kus, B. E., and Beck, P. P. An Approach for Monitoring Bird Communities to Assess Development of Restored Riparian Habitat. In: Faber, P.M. (ed.) California Riparian Systems: Processes and Floodplain Management, Ecology, and Restoration. Riparian Habitat Joint Venture, Sacramento, CA. Ralph, C. J., Droege, S., and Saur, J. R Managing and Monitoring Birds Using Point Counts: Standards and Applications. USDA Forest Service General Technical Report. PSW- GTR 149, RHJV (RIPARIAN HABITAT JOINT VENTURE) Version 2.0. The riparian bird conservation plan: a strategy for reversing the decline of riparian associated birds in California. California Partners in Flight. Unitt. P San Diego County Bird Atlas. Proceedings of the San Diego Society of Natural History.

10 !( 1 RANCHO SANTA FE RD!( 2!( 3!( 6!( 4 LA BAJADA MANCHESTER AVE!(!( 9!( 8 7!( 5 LA NORIA Base Map Source: Encanidas.sid (2005) Miles. Escondido Creek Bird Survey Point Count Stations Legend San Elijo Lagoon Ecological Reserve Point Count Stations

11 Escondido Creek Survey November 19, 2008 POINT COUNT STATION Total SPECIES White-tailed Kite 1 1 Red-shouldered Hawk 1* 0 Red-tailed Hawk 1* 1 2* 1 American Kestrel 1* 1 1 Killdeer 3 3 Mourning Dove 0 Anna's Hummingbird Nuttall's Woodpecker Black Phoebe Say s Phoebe Cassin's Kingbird Western Scrub-Jay 1 1 American Crow 2* 2* 1* 3* 0 Common Raven 1* 0 Bewick's Wren House Wren 1 1 Marsh Wren 3 3 Ruby-crowned Kinglet Wrentit 2 2 Orange-crowned Warbler 2 2 Yellow-rumped Warbler Common Yellowthroat California Towhee 1 1 Song Sparrow Lincoln s Sparrow 0 White-crowned Sparrow Red-winged Blackbird Hooded Oriole 0 House Finch 2* Lesser Goldfinch 0 TOTAL * >50m from station

12 Escondido Creek Survey December 18, 2009 POINT COUNT STATION TOTAL SPECIES Mallard 3 3 Snowy Egret White-faced Ibis White-tailed Kite 1* 0 Red-shouldered Hawk Red-tailed Hawk American Kestrel 1 1 Virginia Rail 2 2 Semipalmated Plover 2 2 Killdeer 4 4 Lesser Yellowlegs 2 2 Least Sandpiper 1 1 Rock Pigeon 10* 0 Mourning Dove White-throated Swift 4 3* 4 Anna's Hummingbird Nuttall's Woodpecker 1 1 1* 2 Downy Woodpecker 1 1 Black Phoebe Say s Phoebe Cassin's Kingbird American Crow * 1* 31 Common Raven 2* 1* 0 Bushtit Bewick's Wren House Wren 1 1 Marsh Wren Ruby-crowned Kinglet 1 1 American Pipit European Starling 10* 3* 0 Orange-crowned Warbler 1 1 Yellow-rumped Warbler Common Yellowthroat California Towhee 2 2 Song Sparrow White-crowned Sparrow Red-winged Blackbird Brewer's Blackbird 1 10* 1 House Finch Lesser Goldfinch 4 4 TOTAL * >50m from station

13 Escondido Creek Survey January 21, 2009 POINT COUNT STATION Total SPECIES Mallard 2 2 Great Blue Heron 1 1 Black-crowned Night-Heron 1 1 White-tailed Kite 2* 0 Red-tailed Hawk 1 1* 1* 1 2 American Kestrel 1* 0 Mourning Dove Anna's Hummingbird Nuttall's Woodpecker Downy Woodpecker Black Phoebe 2 2 Say s Phoebe 1 1 Cassin's Kingbird 1 1 1* 2 American Crow 2* 4 1* 3* 4 Bushtit Bewick's Wren House Wren Marsh Wren Ruby-crowned Kinglet European Starling 2 2 Yellow-rumped Warbler Common Yellowthroat Spotted Towhee 1 1 California Towhee Song Sparrow White-crowned Sparrow Red-winged Blackbird House Finch TOTAL * >50m from station

14 Escondido Creek Survey February 18, 2009 POINT COUNT STATION Total SPECIES Gadwall 3 3 Mallard 4* 4 4 Pied-billed Grebe 5 5 Red-shouldered Hawk 1 1 Red-tailed Hawk American Kestrel 1 1 Clapper Rail Virginia Rail Killdeer Wilson's Snipe 1 1 Mourning Dove Anna's Hummingbird Nuttall's Woodpecker 2 2 Downy Woodpecker 1 1 Black Phoebe Say s Phoebe 1 1 Cassin's Kingbird American Crow Bushtit Bewick's Wren 1 1 Marsh Wren Ruby-crowned Kinglet 1 1 Western Bluebird 2 2 Wrentit 1 1 Northern Mockingbird 1 1 Orange-crowned Warbler 1 1 Yellow-rumped Warbler Common Yellowthroat Spotted Towhee 1 1 California Towhee Song Sparrow White-crowned Sparrow Red-winged Blackbird House Finch Lesser Goldfinch TOTAL * >50m from station

15 Escondido Creek Survey March 18, 2009 POINT COUNT STATION Total SPECIES Mallard 2 1 2* 3 Pied-billed Grebe 1 1 Great Blue Heron 1 2 ON 1 Great Egret 1 10 ON 1 Red-shouldered Hawk 1 1* Red-tailed Hawk 1 1 2* 2 American Kestrel 1 1 Virginia Rail 2 2 Killdeer Mourning Dove Anna's Hummingbird 3 3 NB NB 14 Selasphorus Hummingbird 1 1 Nuttall's Woodpecker Downy Woodpecker Black Phoebe Say s Phoebe 1 1 Cassin's Kingbird * 4 Least Bell s Vireo 1 SM 2 SM 3 American Crow * 2 12 Tree Swallow 1 1 Bushtit NB 2 6 Bewick's Wren 1 1 House Wren 1 1 Marsh Wren 2 NB Northern Mockingbird 1 1 American Pipit 8 8 European Starling Orange-crowned Warbler 1 1 Yellow-rumped Warbler Common Yellowthroat Spotted Towhee 3 3 California Towhee 1 1 Song Sparrow White-crowned Sparrow 1 1 Red-winged Blackbird Hooded Oriole 2 2 House Finch Lesser Goldfinch TOTAL * >50m from station NB = nest building ON = adult on nest NN = presence of nestlings seen or heard FY = adults feeding young or carrying food CH = chicks seen or heard FL = fledglings dependent on parents JV = juvenile birds SM = singing male in suitable habitat PR = pair together in suitable habitat

16 Escondido Creek Survey April 15, 2009 POINT COUNT STATION Total SPECIES Gadwall 1 1 Great Blue Heron ON 5 Great Egret 13 ON 1 1 Sharp-shinned Hawk 1 1 Red-shouldered Hawk 1 1 Red-tailed Hawk 1* 0 American Kestrel 1 1 Virginia Rail 1 1 Killdeer Mourning Dove Anna's Hummingbird Selasphorus Hummingbird 1 1 Nuttall's Woodpecker Downy Woodpecker Black Phoebe Cassin's Kingbird Western Kingbird 1 1 Least Bell's Vireo 1 SM 0 Hutton's Vireo 1 1 American Crow Cliff Swallow Bushtit 14 5 NN House Wren 1 1 Marsh Wren Wrentit 1 1 American Pipit 4 4 European Starling Yellow Warbler 1 1 Common Yellowthroat Yellow-breasted Chat 2 SM 1 SM 1 SM 0 California Towhee Song Sparrow White-crowned Sparrow 3 3 Black-headed Grosbeak 2 SM Red-winged Blackbird Great-tailed Grackle 1 1 Brown-headed Cowbird 2 PR Hooded Oriole House Finch Lesser Goldfinch American Goldfinch 2 2 House Sparrow 3 3 TOTAL * >50m from station NB = nest building ON = adult on nest NN = presence of nestlings seen or heard FY = adults feeding young or carrying food CH = chicks seen or heard FL = fledglings dependent on parents JV = juvenile birds SM = singing male in suitable habitat PR = pair together in suitable habitat

17 Escondido Creek Survey May 22, 2009 POINT COUNT STATION Total SPECIES Pied-billed Grebe 1 1 Great Blue Heron 2 NN 0 Great Egret NN 2 White-tailed Kite 1 1 Red-shouldered Hawk 1 1 Red-tailed Hawk Clapper Rail 1 1 Virginia Rail 2 CH 0 Mourning Dove Anna's Hummingbird Nuttall's Woodpecker Downy Woodpecker 1 1 Black Phoebe 2 FY FL 1 4 Cassin's Kingbird 1 1 Least Bell's Vireo 3 FY 1 1 American Crow 4* Cliff Swallow Bushtit Bewick's Wren 1 1 House Wren 1 1 Marsh Wren Wrentit 1 1 Northern Mockingbird 1 1 European Starling 1 1 Orange-crowned Warbler 1 1 Yellow Warbler Common Yellowthroat Yellow-breasted Chat Spotted Towhee California Towhee 2 JV 2 2 Song Sparrow 10 7 FY FL 8 FL 6 50 Black-headed Grosbeak Red-winged Blackbird Brown-headed Cowbird PR Hooded Oriole 1 1 House Finch FY FL 9 76 Lesser Goldfinch FL 5 10 American Goldfinch 2 2 TOTAL * >50m from station 0 NB = nest building ON = adult on nest NN = presence of nestlings seen or heard FY = adults feeding young or carrying food CH = chicks seen or heard FL = fledglings dependent on parents JV = juvenile birds SM = singing male in suitable habitat PR = pair together in suitable habitat

18 Escondido Creek Survey June 19, 2009 POINT COUNT STATION Total SPECIES Pied-billed Grebe 1 1 Great Blue Heron 1* 1 1 Great Egret White-tailed Kite 2 JV 0 Red-tailed Hawk 1* 1* 1 1 Cooper's Hawk 1* 0 Mourning Dove White-throated Swift 2 2 Anna's Hummingbird Selasphorus Hummingbird 1 1 Nuttall's Woodpecker Downy Woodpecker 2 2 Black Phoebe Say s Phoebe 1 1 Cassin's Kingbird Least Bell's Vireo 2 1 1* SM 3 American Crow 3* 5 FY 0 Cliff Swallow Bushtit Bewick's Wren 1 1 House Wren 1 1 FL 2 3 Marsh Wren JV 1 FL 0 Western Bluebird 1 1 Northern Mockingbird European Starling 6 6 Yellow Warbler Common Yellowthroat 4 3 FL Yellow-breasted Chat 1* * 4 Spotted Towhee 1 1 Song Sparrow FL Black-headed Grosbeak Red-winged Blackbird FY 42 Brown-headed Cowbird Hooded Oriole 1 1 House Finch 12 FL Lesser Goldfinch TOTAL * >50m from station NB = nest building ON = adult on nest NN = presence of nestlings seen or heard FY = adults feeding young or carrying food CH = chicks seen or heard FL = fledglings dependent on parents JV = juvenile birds SM = singing male in suitable habitat PR = pair together in suitable habitat