Monarchs Estimated at Overwintering Sites Since 1997

Numbers of monarchs estimated at overwintering sites since 1997 are listed below. These numbers reflect observations from trained volunteers. Not all sites can be checked every season. However we now have baseline data for population fluctuations. When sites were not visited, no number appears in the space on the chart.

SITE NAME	2012	2011	2010	2009	2008	2007	2006	2005	2004	2003	2002	2001	2000	1999	1998	1997
COUNTY: Mendocino
Anchor Bay	5			0										0		1310
China Gulch, Gualala	5													0	0	2000
Fish Rock #1, Anchor Bay	0							0						0	50
COUNTY: Sonoma
Bay Flat Rd., Bodega Bay	0											3	700	450
Bodega Dunes Campground, Bodega Bay	10	600		0	0	0	0	0	34	160		4	2500	300
Monarch Glen, The Sea Ranch	0							0						0	1600	440
Ranch Road, Bodega Bay	0											0	6	0		6220
COUNTY: Marin
Alder Rd., vortex (Larch, Ocean St)	150	7700	0	1700	390	1000	3520	950	8880	10400	2300
BPUD Sewer Ponds, Bolinas	0	0	0	0			0		122	5	0	0	1500
Chapman Ravine, Stinson Beach	0	800	0	49	3	0	0	0	8050	2000	2000	1000	15150	3000	4000	15500
Fort Baker, GGNRA	10	500	0	0	5	0	550	0	2200	9	0	15	310	200	1600
Fort Barry, Marin Headlands (Youth Hostel)	5	0	0	0	0	0	0	1	0	0	0	0	0	0	0	2550
Purple Gate, Bolinas	530	400	0	27	20	0	2600	130	7200	300	2000	3	12050	1500	8050	12000
Terrace Ave., Bolinas	0	0	0	0	0	0	0			0	0	0	2000	1000	2050
Terwilliger Grove, Muir Beach	0	0	0	0	0	0		365		54	35	0	305	500	500	2100
COUNTY: San Francisco
Fort Mason, Near Bldg. 201	2	11	3	1	6	14				0	0	0	0	0	110	150
Golden Gate Park, 41st & Fulton	0	0	1	1	0	0					0		0	0	0	700
Golden Gate Park, Bot. Garden	4	4	2	1	7
Golden Gate Park, Strawberry Hill		3
John McLaren Park		0
Rob Hill / The Presidio	2	2	2	3	5	1					0
Stern Grove / Pine Lake	3	15	0	0	4
Treasure Isl.	22	240
Yerba Buena Isl.	10	365
COUNTY: Solano
Mare Island, Vallejo	0														50
COUNTY: Contra Costa
Point Pinole, Point Pinole	4	785	0	0	0	0	0	0	879		0	3	600	1000		5000
U.C. Berkeley Extension, Richmond	0										0	150	0		12	3000
COUNTY: Alameda
Albany Hill, Albany	45	2137	9	18	83	0		350			0	0	0	3	85	3000
Ardenwood Historical Farm, Fremont	1682	4188	224	883	683	182	1595		2036	1500		1000	1530	135	5000	25000
Coyote Hills, Fremont			30	72			420		249	300			500	210	500	700
Chuck Corica Golf Course, Bay Farm Island	2171			100	0		2250			750	2000	3000			1500
Oyster Point Regional Shoreline	0
San Leandro Golf Course, San Leandro	4000	7000	3000	5000	5000	6000	5625	4900		2500	1000	1050	2050	2000	20000	25000
Skywest Golf Course, Hayward	37		0	54								1000	5600	5000
COUNTY: San Mateo
Whitehouse Creek, Año Nuevo		2
COUNTY: Santa Cruz
Escalona Gulch, Capitola	200		4	9	370	0	2	15	9	0	18	105	166	625	1200
Home of Peace Cemetary, Santa Cruz					3	0		34	5	1		1	27	6	6
Lighthouse Field, Santa Cruz	3200	18100	4000	4000	2607	5700	10300	14000	9600	11000	3200		35000	9500	50000	70000
Lifeguard Headquarters, 14th Ave., Santa Cruz	0			14	14	7	13	20	21	0	4	13	43
Manresa State Beach	0
Moran Lake, Moran Lake	2500	4500	3000	2276	4023	2200	6600	3400	4500	6000	1000	1500	4000	4500	8000	70000
Natural Bridges State Beach, Santa Cruz	500	3000	2300	1300	3500	2700	7300	3900	9600	5700	6000	3000	20000	15000	60000	120000
New Brighton / Potbelly, Aptos	400		24	41	35	12	2015	617	500	3	8	64	2640	2000	445
Oxford & Alamar	0
Rispin Mansion, Santa Cruz	9		2	4	7	3	9	11	16	0	0	17	11	20	5
Seascape Golf Course, Aptos	2500		1000	23	1560	48	2000		950		4	1400	1050	280	240
South Branciforte, Buena Vista	7		2	7	8	5	32	48	75	0	0	23	24	27	2
UCSC Arboretum	0
COUNTY: Monterey
Andrew Molera State Park	1852	4201	1551	155	4903	607	2858	8239	4759	13888	917	4470
Butterfly Grove Sanctuary, Pacific Grove	10790	12265	4968	793	17866	8181	28746	12199	10867	22802	4700	14960	20000	25000	35000	45000
Los Padres National Forest/Caltrans Grove	8	6
Moss Landing Middle School, Moss Landing													0
Pacific Grove Golf Course	0
Palo Colorado, South of Carmel Highlands		0	0		0	1	0	0	10	33	0	300	0
Paskett Creek, South of Big Sur	610	643	0	110	397	0	916	928	786	3083	23	95	0
Point Lobos State Park, Carmel Bay	117	791	39	6	1274	2	1430	14	1198	4306	3	960			6000
Prewitt Creek		0	0		0	0	5	0	0	199	0	105
Private Property near Big Sur	15671	9821	2076	3671	5333	6629	14203	16132	32536	21918	5950	10313
Sycamore Canyon, Big Sur		0	0	0	1290	4	4	26
Washington Park, Pacific Grove	0	61	0	0	0	2	11795	2	4325	2750			0
COUNTY: San Luis Obispo
Alapay, North of Cayucos													1700
Avila Golf Course, San Luis Obispo						0			0			3000	1000
Bowden Estates, San Luis Obispo	0	4	3	4	0	1	49	25	50	950	5	200
Blacklake I, E of parking area, W of Entrance		9713	7120	1632	2862	0	0	2442	3250	4723
Blacklake II, NW end of meadow, S of Lake		7583	1775	2240	5390	1921	4080	7110	11714	8500	3900	7000
Camp Keep, Montana De Oro State Park		0	0	0	825	0	0	0	1050	300	5	1000	8000	1000	2000	50000
Eagle Rock, Morro Bay	80	700	65	15	18	2	463	0	0	0	0	0	5000
French Hospital, San Luis Obispo		70	136	85	12	23	53	10	50
Halcyon Hill, Halcyon	4255	7547	4593	622	825	177	2460	4100	0	6400
Hamlet, Cambria	867	6073	1	0	0				600	4600						25000
Higuera & Elks Ln SLO Cemetery, San Luis	104	1181	290	404	140	120	565	900	700	860	150	650	3000
Kaberline, Cayucos		13	1	15	10	8	30	100	20	0	0	25	7600	2500	7000	35000
La Due, Halcyon		3	0	0		0	0	0	0	0
Monarch Lane, Los Osos (modified site)	13	395	63	246	600	400	1890	100	280	1160	150	2000	3000	1500	4000	3000
Morro Bay Golf Course, Morro Bay	10976	9494	7292	3720	1375	3880	7242	8300	750	3535	806	1500	6000	5300	40000	20000
Main & South St., Morro Bay		9	1	0	5	5	0	2	0	0	10	5000	1500	50
Main & Surf St., Morro Bay		12	20	2		2	0	0	2	1	1	3	25
Morro Bay State Park Campground, Morro Bay	121	21	160	571	335	550	800	0	3750	8105	2000	5000	13000	3100	0	100
N. Santa Rosa, San Luis Obispo		220	12	0	75	0	0	100	350	300
Nipomo, S. Oakglen									0	160
Oceano Campground, Oceano	3198	4708	2656	1420	2470	1500	2600	700	2725	7406	10811	4400	7500	8000	9850	75
Pecho Rd., Los Osos (Pecho & Rosin Dr.)	2342	3275	3689	720	880	500	2000	2000	3000	3000	380	2000	100	1500	4100	15000
Pike, Halcyon	179	199	2944	296	175	455	1900	1800	5503	470	0	450
Pismo Beach, Maintenance Yard Complex					0	0		0	0	0	0	0	4	0	0	700
Pismo Beach, North Beach Campground	28086	18000	21286	17200	23050	16900	22050	24840	25575	38438	30160	33000	26100	60000	115100	100000
Price & Solar, Pismo	238	20	162	0	26	38	150	20	210	50	184	40
Sweet Springs, Los Osos	104	8	4	10	120	6	36	0	400	500	230	0	1000	100	0	925
Toro Creek, South of Cayucos		492										0	5000
Villa Creek, North of Cayucos		270	2150	500	400	1060	3775	6000	1200	3300	350	2500	13500
Woodlands Village Monarch Habitat, Nipomo	3100	1075	50	164
COUNTY: Santa Barbara
Arroyo Hondo Preserve	6
Arroyo Quemado, Near Refugio State Beach	3													3000
Atascadero Creek, Santa Barbara	4										0	5470	8912	4000		20000
Boys and Girls Club, Goleta								5		17
Butterfly Lane, Montecito													0
Carpinteria Business Park, Carpenteria												13	5
Carpinteria Creek, Carpenteria	1500	1800				30	4250	6300	3200	6150	4500	1800	22500	13000	9000	50000
Devereux School, Santa Barbara	298	1850	570					800		475	350	2306	7320
Douglas Family Preserve, Santa Barbara	1	84					50	60
Eagle Canyon, Near Naples									5		40	9000	4230	1430
Ellwood Central and West, Goleta	0		0		8700		10000	0					30	2200		35000
Ellwood, Hollister & Coronado Dr., Goleta	0	33	318		45		600	25			4		6	37	200	750
Ellwood Main, Goleta	17150	21800	27600	6500	12000	11000	19000	54700	16680	18400	4500	35000	58000	25000	20000	25000
Ellwood North, Goleta	0		3	1500	131		1800	1400	4550	3160	6	82	11650	2060
Ellwood / Sandpiper Golf Course	655	8100	8309		2800		3000	775			3		10	55
El Refugio Ranch, Near Refugio State Beach												180		12500
Gaviota State Beach, Gaviota	6397	24										0		500
Hale Park, Montecito													3		7
Hidden Valley Park, Santa Barbara													0
Honda Valley / SBCC	463	6100	2850		54		975	570	110	36	350	100	20
Lambert Road, Summerland	50												2
Las Armas, Goleta														0
La Mesa Park, Santa Barbara	55	25	775				400	85
La Posada Hill, Goleta		0						6					0	0
Llano & Mariposa Ln / Santa Barbara								25
Lookout Park, Summerland	0						0						2
Los Carneros Lake, Goleta		15	27					570			9		0	58
Maria Ygnacio Creek, Goleta	5	35	59				15	1036		0	40			530
Maria Ygnacio / Ramada Rd.							35
More Mesa, Goleta													3	200
More Ranch Road, Near Goleta Beach											30		4500
Music Academy, Montecito											3	17	0	50	2
Oil & Gas Buffer Zone, Carpenteria	2200				4000	3050	3000		100					800	2000	8000
Ortega Hill, Montecito and Summerland	650				1500		4500	5800	6050	5800
Padaro Lane, Summerland						350		0	2900	1280	1525	5700		4000	30000	55000
Preisker Park, Santa Maria	21												450			350
Rincon Creek, Carpenteria											20		300	38
Rincon Road, Carpenteria													500	3680
San Jose Cr / Elks Club, Goleta	51	2046						307		6	30	82	1190	2300
Tajiguas Canyon, Goleta											2500	800		500
Tecolote Canyon, Goleta									3		12	3	3	100
Vandenberg AFB, 35th Street	788	0
Vandenberg AFB, Airfield Rd.	0	303
Vandenberg AFB, Archery Range	0	3										575		250	7200	17000
Vandenberg AFB, Bear Creek	24
Vandenberg AFB, Cross Rd.	10	15												0
Vandenberg AFB, Family Camp Site		0													0	600
Vandenberg AFB, Marshalia Golf Course	35														3000
Vandenberg AFB, Mesa Rd / Arguello Blvd.	774	2642										410	2800	1210	50	6500
Vandenberg AFB, Spring Canyon	1025	6015					2899	700				4800	8830	5780	1500	50000
Vandenberg AFB, Tangair Rd.	692	2563					329	5095				0		3860	8100	25500
Vandenberg AFB, Upper Spring Canyon	1							60							50	60000
Vandenberg AFB, Water Treatment Plant	613	302
Vandenberg Village, Lompoc												740			3200	600
Veronica Springs, Santa Barbara													0
COUNTY: Ventura
Arrundel Barranca, Ventura	900	2500	6000		360	1300	4600	1833		4650	15	2900	2500	4900	12000	40000
Big Sycamore Canyon, Pt. Mugu State Park	0	10	200		85	10				110	10	15	90	600	5000	7000
Camino Real Park, Ventura	5750	10000	9500		1300	1100	8300	6400		590	40	750	800	1800	100	20000
Harbor Blvd. Ventura	0	1650	1700		1000	200	450	3300		4960	600	1300	4300	3000	30000	5000
Harmon Barranca, Ventura						50	1			30	40	3050				1000
Little Sycamore Canyon, Private Camp					30					365	60	2150	2020	500	8000	25000
Ocean Ave. Park, Ventura	3200	4000	6000
Oxnard College, Oxnard		30	30		1200									15
Taylor Ranch, North Ventura			500		950							0	9000	8000	4000
Vista Del Mar, Ventura			0		5500	4700	1400			4600	4200	18300		4000	6000	45000
COUNTY: Los Angeles
Ballona Wetlands, Playa Del Rey										80	0	90	5			1150
Banning Park, Wilmington					20					6		10	50		125
Busch Dr. & Pacific Coast Hwy., Malibu			1000		2000	3600		2300		535		200	8200	1500	7000	6500
Chevron Refinery, El Segundo (Kansas St.)										10		500	25		250
Encinal Canyon, Malibu					0					10		5	15			7500
El Dorado Nature Center, Long Beach (#1)	5	30	30		40	25	25			8		30	15	10	500	2500
El Dorado Nature Center, Long Beach (#2)	5	5								0		3	10	10
Heartwell Park, Lakewood													0		100	25
Leo Carrillo State Beach, Malibu	3		15		40	10		35		155	45	5	60	300	4500	100
Malibu Creek (Serra Rd.), Malibu					4	15				300	10		1	200	4000	5000
Old Kinney‐Stahly Place, Malibu																10500
Recreation Park (north), Long Beach					25					0		40	130		70	150
Recreation Park (south), Long Beach					120					3		3	20		0	750
Schabarum Co. Park, Rowland Heights					25	6					7			2	60
Via La Selva & Via Capay, Palos Verdes										3		10	150		300
Wilderness Park, Redondo Beach					2	12				20		35	0		300	200
Woodlawn Cemetery, Santa Monica			75		30					30	60	600	15		175
27540 Hwy. 1, Malibu										25			5			400
2817 Via La Selva, Palos Verdes										6		10	0		800
COUNTY: Orange
Aliviso Resort, Laguna Beach																200
Bolsa Chica, Huntington Beach	25	6	15
Doheny State Beach, Dana Point		0			3				0	0		0	15	10	120	150
Festival of the Arts, Laguna Beach					5
Golden West College, Huntington Beach	15	50	60		20	8	15	140	235	0		35	1	0	800
Gum Grove Park, Seal Beach	20	40	40		25	2				0		0	0	20	0	2000
Hospital Site, Dana Point					5					0		0	0	5	80	650
Huntington Central Park, (amphitheater)	12	30	30	17	25	60	25	450	123	0		19	1	0	1500	3800
Huntington Central Park, Gothard Sr. Site	3	2		4	0		40		45	0		1	1	0	0	3000
Junipera & Presidente, San Clemente		0	5
Marina Park, Seal Beach	0		7
Naval Weapons Station, Seal Beach															200
Norma Gibbs, Grahm St., Huntington	2	25	100	175	30	1		60	20	1		8	0	7	8	350
San Clemente State Park, San Clemente	225	175	240	15	100	1	20	110	104			0	20	1	150
Sundance Dr., Costa Mesa	10	280			3	10	3		20	6		23	5	0	1500	3500
Trafalger Ln., San Clelmente		1	5
COUNTY: San Diego
Camp Pendleton, Camp Pendelton			2	12	50		300	830	130	15	20		225	10	5	10000
Camp Pendleton, Tomato fields			20	50	130			30
Camp Pendleton, San Onofre Creek			35	1	150
Crest Dr., Encinitas										0			0	0		50
Crest Rd., Del Mar	0														0	300
El Camino Real & Chestnut, Carlsbad	20	0			25	1				0	0	0	0	2	60	150
El Prado & 6th Street, Balboa Park		0			1					0		0	0	6	0	100
Eucalyptus Park, Chula Vista	30	0	20	0	50	0	0			3		0	0	25	190	250
Grape Street Park, Balboa Park	10	30	30	0	90					0		0	0	0	30	200
Hidden Pines, Del Mar	30	0			5			0		0	0	15	1	0	5	170
Hosp Grove, Carlsbad	35	5	40		15	0		0	0	0	0	6	0	0	200	1100
Mount Soledad, La Jolla, Romero Dr.										0		0		0	70	500
Nogales Site, Del Mar	75	15	20		75	20	30	12	45	3	0	1	40	25	400	1100
Pottery Canyon, La Jolla		0			0					1		0	0	0	15	55
Presidio Park, Old Town	40	10	50	5	60	20	25	20	50	13	5	25	32	17	100	250
Quail Botanical Gardens, Encinitas		15	40		30	10	20			15	15	6	17	0	7	150
Quail Gardens Dr., Encinitas												0	0	0		50
San Dieguito County Park, Solana Beach					0					0		0	0	0	8	120
South Torrey Pines State Park	0		2			0				0	0	5	0	0	5	80
Space Theater Way, Balboa Park		10			10					0		2	0	0	0	100
UCSD Che Cafe	0	0	1		0	0			0	0	0	0	0	3	50	450
UCSD Coast Site, Azul St.	25	2	90	5	30	0	20	10	35	0	0	15	26	10	350	2400
UCSD Mandeville	0	0	10		1	0			0	0	0	1	1	1	750	8000
UCSD Salk Site, Near Salk Institute	0					0				0	0	0	0	0	325	0
UCSD Weiss, Near the Weiss Theater	0	0	0		1				0	0	0	2	6	1	20	40
Veterans Park, Imperial Beach	15	5	12
COUNTY: Baja California
El Sauzal, Near Mex. 1 and Mex. 3									40	20			48	100	600	2000
La Mission									3	1			12		7	30
La Salina									45	60			80	50	800	1700
Moneadero, 12 miles south of Ensenada										0			4		250	50
Rancho Santa Anita (Mex. 3)									6	1			54		100	900
COUNTY: Phoenix, AZ
Desert Botanical Garden		1	12
Rio Salado Habitat Restoration Area‐Main		42	17
Rio Salado Habitat Restoration Area‐N. Anex		26	2
Rio Salado Habitat Restoration Area‐S. Anex		18	6
South Mountain & 24th Street		15	10
COUNTY: Tempe, AZ
McClintock & Salt River Riparian Area		12	5

Compiled by Mia Monroe, Sarina Jepsen, and Candace Fallon
Updated November 1, 2013

Monarchs Estimated at Overwintering Sites Since 1997

Monarchs Estimated at Overwintering Sites Since 1997

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