ITIS Basic Information
Common Name: Coast Horned Lizard
Scientific Name: Phrynosoma blainvillii
Species Code: PHABLA
Management Category: VF (species with limited distribution in the MSPA or needing specific vegetation characteristics requiring management)
Occurrence Map

Historically present
Currently present
Currently not detected
Table of Occurrences
Loading...

Goals and Objectives

Goal: Maintain, enhance and restore coastal sage scrub on Conserved Lands in the MSPA that supports or has the potential to support VF species (i.e., cliff spurge, Palmer's goldenbush, San Diego barrel cactus, snake cholla, Blaineville's horned lizard, California gnatcatcher, San Diego black-tailed jackrabbit) and to incidentally benefit a diverse array of other species (e.g., San Diego thornmint, willowy monardella, Hermes copper, Quino checkerspot, coastal cactus wren) so that the vegetation community has high ecological integrity, and these species are resilient to environmental stochasticity, catastrophic disturbances and threats, such as very large wildfires, invasive plants and prolonged drought, and will be likely to persist over the long term (>100 years).

Regional NFO 2017, 2018 VF
MON-RES-GEN PHABLA-1

Management units: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11

In 2017 continue a next-generation DNA sequencing study to characterize the phylogeographic and population genetic structure Blainville's horne lizard in southern California, including Conserved Lands throughout the MSPA. This species is a target for regional-scale connectivity within and between core areas of the MSPA and will provide information important to identify areas that may require management to improve connectivity for small vertebrates.

Action Statement Action status Projects
RES-1 Submit project metadata, genetic datasets, analyses and report to the MSP Web Portal. In progress
Criteria Deadline year
Study completed and report submitted by 2018 2021
Threat Name Threat Code
Loss of connectivityLOSCON
Regional NFO 2018 VF
MON-PRP-MONPL PHABLA-2

Management units: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11

In 2018, develop a long-term Blainville's Horned Lizard Monitoring Plan to track their distribution and status, habitat associations and level of threats in chaparral, coastal sage scrub and grassland vegetation communities across Conserved Lands in the MSPA. The plan should integrate with the Chaparral, Coastal Sage Scrub and Grassland Vegetation Monitoring Plan to include sampling at long-term vegetation monitoring plots. The monitoring plan should build upon previous surveys, habitat assessments and modeling to develop specific questions, monitoring methods, a statistically valid sampling design, sampling locations, and standardized protocols for determining the status and abundance of the lizard and for assessing habitat and threats at each sampling site to determine vegetation management needs. The plan should include guidelines for data analysis and preparation of a report with monitoring results and vegetation management recommendations.

Action Statement Action status Projects
PRP-1 Submit project metadata and Blainville's Horned Lizard Monitoring Plan to the MSP Web Portal. On hold
Criteria Deadline year
Blainville's Horned Lizard Monitoring Plan completed in 2018 2021
Code Obj. code Statement
PHABLA-3 MON-IMP-MONPL In 2019, begin implementing long term Blainville's horned lizard monitoring as specified in the Blainville's Horned Lizard Monitoring Plan. Prepare a report detailing lizard and habitat and threat assessment results and with site specific vegetation management recommendations.
Regional NFO 2019 VF
MON-IMP-MONPL PHABLA-3

Management units: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11

In 2019, begin implementing long term Blainville's horned lizard monitoring as specified in the Blainville's Horned Lizard Monitoring Plan. Prepare a report detailing lizard and habitat and threat assessment results and with site specific vegetation management recommendations.

Action Statement Action status Projects
IMP-1 Submit project metadata, datasets, analyses and monitoring report with management recommendations to the MSP Web Portal. waiting for precedent action
Criteria Deadline year
Blainville's Horned Lizard Monitoring and Report completed by 2020 2021
Code Obj. code Statement
PHABLA-2 MON-PRP-MONPL In 2018, develop a long-term Blainville's Horned Lizard Monitoring Plan to track their distribution and status, habitat associations and level of threats in chaparral, coastal sage scrub and grassland vegetation communities across Conserved Lands in the MSPA. The plan should integrate with the Chaparral, Coastal Sage Scrub and Grassland Vegetation Monitoring Plan to include sampling at long-term vegetation monitoring plots. The monitoring plan should build upon previous surveys, habitat assessments and modeling to develop specific questions, monitoring methods, a statistically valid sampling design, sampling locations, and standardized protocols for determining the status and abundance of the lizard and for assessing habitat and threats at each sampling site to determine vegetation management needs. The plan should include guidelines for data analysis and preparation of a report with monitoring results and vegetation management recommendations.
Blaineville's Horned Lizard Genetics Study
The proposed study will provide data on whether coast horned lizard populations are genetically interconnected across the NCCP reserve system, or whether gene flow has occurred recently but is no longer possible due to habitat fragmentation.
Lusardi Creek Restoration and Invasive Plant Removal
This project is working to eradicate invasive species and support native plants along Lusardi Creek. Many areas have already been treated and are recruiting natives naturally. Other areas are being planted with natives after invasive plant removal. The current goals include: 1) treat artichoke in several upland areas, 2) continue removing tamarix in the creek, 3) treat any regrowing Peruvian pepper, 4) treat any remaining pampas grass or tree tobacco, 5) work on an overall restoration plan. See the map link below for detailed treatment information.
SR 94 Wildlife Infrastructure Plan
Proposed road improvements to SR 94 provide an opportunity to mitigate the potential barrier effects of the highway. This project identifies where improvements to existing infrastructure on SR-94 could improve connectivity across the South County preserves, using Best Management Practices from the scientific literature; recommends wildlife movement monitoring to identify where new crossings are needed; and identifies where additional conservation would enhance the integrity of South County linkages. The review prioritizes infrastructure improvements of 35 existing undercrossings inspected by wildlife experts in the field along 14.6 miles of SR-94 where the highway bisects conserved lands. The majority of the recommendations for infrastructure improvement focus on increasing the diameter, and thus the openness ratio (cross-sectional area divided by length), of the undercrossing itself, removing vegetation and debris blocking the undercrossing, restoring habitat in the approach to the undercrossing, and installing fencing to both (1) keep animals off the highway and (2) funnel wildlife to the undercrossings.

Current Distribution Rangewide

Native to California and occurs along the Pacific coast from the border of Baja California as far north as Santa Cruz, and inland as far north as Shasta County [1]. A very small disjunctive population also occurs in Siskiyou County.

Known Populations in San Diego County

Found in MUs 1, 3, 4, 5, 6, 7, 8, 9, 10, and 11 within the MSPA [2].

List Status

SSC [3]

Habitat Affinities

Prefer open areas with sandy soil and low vegetation, but are also found in a wide variety of habitats including valley-foothills, conifer, riparian habitats, grasslands, and semiarid mountains [4]. In southern California, Blainville’s horned lizard is commonly found in chaparral habitats with native ant colonies, and areas with loose sandy soils [5]. During periods of inactivity and hibernation, individuals will burrow into loose soil under logs, rocks, mammal burrows, or crevices. Does not require permanent water.

Taxonomy and Genetics

Montanucci (2004) concluded in a morphological study, that P. coronatum is in fact four separate species (P. blainvillii, P. cerroense, P. coronatum, and P. wigginsi) [6]. Out of the four species, P. blainvillii is the only species known to occupy California [7].

Seasonal Activity

Diurnal species [8]. During spring and fall seasons most activity occurs in the middle of the day, but is restricted to morning and late afternoon activity during hot summer months. Nocturnal activity may occur during weather events of extreme heat. Individuals during fall and winter are inactive in most areas. Seasonal movements or migration has not been reported, and hibernation is found within the normal area of activity [8].

Life History/Reproduction

The reproduction season can vary from year to year depending on local conditions [9]. Females will lay their eggs (6-21) in a nest under the soil or in a burrow during the months from May to June. Eggs hatch from August to September. Females may lay two clutches of eggs per year. Adults are known to live up to 10 years in captivity [10]

Diet and Foraging

Forages between shrubs in open areas, generally near ant nests [9]. Primarily feeds on ants, but will also feed on moth larvae, small beetles, wasps, grasshoppers, spiders, and caterpillars [10].

Threats

Habitat destruction from human development and agriculture, and the spread of nonnative Argentine ants which displace the native food source has threatened and eliminated Blainville’s horned lizard from many areas [11]. The lizard was also extensively exploited by the pet trade until commercial collecting was banned in 1981 [12].

Literature Sources

[1] Hollingsworth, B. & Hammerson, G.A. 2007. Phrynosoma coronatum. The IUCN Red List of Threatened Species 2007.

[2] MSP-MOM. 2016. Management Strategic Plan Master Occurrence Matrix.

[3] California Department of Fish and Wildlife, Natural Diversity Database. July 2017. Special Animals List. Periodic publication. 51 pp

[4] Grismer, L. Lee. 2002. Amphibians and reptiles of Baja California, including its Pacific islands and the islands in the Sea of Cortés. Berkeley: University of California Press.

[5] Fisher, R.N., A.W. Suarez, and T. J. Case. 2002. Spatial patterns in the abundance of the Coastal Horned Lizard. Conservation Biology 16:205–215.

[6] Montanucci, R. 2004. “Geographic Variation in Phyrnosoma coronatum (Lacertilia, Phrynosomatidae): Further Evidence for a Peninsular Archipelago.” Herptologica 60(1):117–139.

[7] Reeder, T.W., and R.R. Montanucci. 2001. A phylogenetic analysis of the horned lizards (Phrynosomatidae: Phrynosoma): evidence from mitochondrial DNA and morphology. Copeia 2001:309-323.

[8] Baharav, D. 1975. Movement of the horned lizard Phrynosoma solare. Copeia 1975:649-657.

[9] Pianka, E. R., and W. S. Parker. 1975. Ecology of horned lizards: a review with special reference to Phrynosoma platyrhinos. Copeia 1975:141-162.

[10] Stebbins, R. C. 1954. Amphibians and reptiles of western North America. McGraw-Hill, New York. 536pp.

[11] Jennings, M.R. 1987. Impact of the curio trade for San Diego Horned Lizards (Phrynosoma coronatum blainvillii) in the Los Angeles Basin, California: 1885- 1930. J. Herpetol. 21(4):356-358.

[12] Jennings, M.R. 1988. Phrynosoma coronatum.. Cat. Amer. Amph. Rept. 428.1-5. ______ and M.P. Hayes. 1994. Amphibian and reptile species of special concern in California. Final Report, Contract 8023. California Department of Fish and Game, Inland Fisheries Division, Sacramento, California.