Phyllospadix scouleri 

Scope: Global
Language: English

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Taxonomy [top]

Kingdom Phylum Class Order Family
Plantae Tracheophyta Liliopsida Najadales Zosteraceae

Scientific Name: Phyllospadix scouleri Hook.
Common Name(s):
English Surf Grass, Species code: Ps

Assessment Information [top]

Red List Category & Criteria: Least Concern ver 3.1
Year Published: 2010
Date Assessed: 2007-10-23
Assessor(s): Short, F.T., Carruthers, T.J.R., Waycott, M., Kendrick, G.A., Fourqurean, J.W., Callabine, A., Kenworthy, W.J. & Dennison, W.C.
Reviewer(s): Livingstone, S., Harwell, H. & Carpenter, K.E.
This is a common species within suitable habitat and the population status is thought to be stable. There are no major threats although there are some localized declines due to coastal development and mechanical damage and the species is slow to recover from damage. This species is listed as Least Concern.

Geographic Range [top]

Range Description:Phyllospadix scouleri occurs in the Pacific from Southeast Alaska to the tip of Baja California and Mexico.
Countries occurrence:
Canada; Mexico; United States
FAO Marine Fishing Areas:
Pacific – eastern central; Pacific – northeast
Additional data:
Range Map:Click here to open the map viewer and explore range.

Population [top]

Population:This is a common species in suitable substrate. The population status is thought to be stable.
Current Population Trend:Stable
Additional data:
Population severely fragmented:No

Habitat and Ecology [top]

Habitat and Ecology:Along the Pacific coast of North America, this species inhabits the lower intertidal and shallow subtidal zone (Green and Short 2003). Phyllospadix spp. grow on rocky substrates in regions with high wave exposure (Hemminga and Duarte 2000).

Surfgrass (Phyllospadix spp.) are not found where sea surface temperatures exceed 21°C in winter or 27°C in the summer. Surfgrass has a low tolerance to higher temperatures which suggests that populations in Baja California Sur might be impacted by global climate change. Phyllospadix scouleri is distributed higher in the lower intertidal and upper subtidal zones than P. torreyi (Ramirez-Garcia et al. 2002).

Phyllospadix scouleri dominates space and persists through all seasons without serious damage by disturbances such as storm waves. This species is long-lived and persistent and may preempt space, preventing other species from invading. This species is slow to recover after removal (Turner 1985).
Generation Length (years):6

Threats [top]

Major Threat(s): There are no major threats to this species. Localized threats include coastal development and modifications and over-water structures in the form of ferry terminals, commercial docks. Mechanical damage from boats and dredging is also a minor localized threat.

Conservation Actions [top]

Conservation Actions: There are no known species-specific conservation measures for this species. It is not clear if the federal, provincial or state, or local administrative laws and ordinances recognize this species in the Northeast Pacific (Green and Short 2003).

Classifications [top]

9. Marine Neritic -> 9.2. Marine Neritic - Subtidal Rock and Rocky Reefs
9. Marine Neritic -> 9.5. Marine Neritic - Subtidal Sandy-Mud
9. Marine Neritic -> 9.9. Marine Neritic - Seagrass (Submerged)
12. Marine Intertidal -> 12.1. Marine Intertidal - Rocky Shoreline
12. Marine Intertidal -> 12.2. Marine Intertidal - Sandy Shoreline and/or Beaches, Sand Bars, Spits, Etc

In-Place Research, Monitoring and Planning
In-Place Land/Water Protection and Management
In-Place Species Management
In-Place Education
1. Residential & commercial development -> 1.2. Commercial & industrial areas
♦ timing:Ongoing    
→ Stresses
  • 1. Ecosystem stresses -> 1.2. Ecosystem degradation
  • 2. Species Stresses -> 2.2. Species disturbance

4. Transportation & service corridors -> 4.3. Shipping lanes
♦ timing:Ongoing    
→ Stresses
  • 1. Ecosystem stresses -> 1.2. Ecosystem degradation
  • 2. Species Stresses -> 2.2. Species disturbance

Bibliography [top]

Green, E.P. and Short, F.T. 2003. World Atlas of Seagrasses. University of California Press, Berkeley.

Hemminga, M.A. and Duarte, C.M. 2000. Seagrass Ecology. Cambridge University Press, Cambridge.

IUCN. 2010. IUCN Red List of Threatened Species (ver. 2010.3). Available at: (Accessed: 2 September 2010).

Ramirez-Garcia, P., Lot, A., Duarte, C.M., Terrados, J. and Agawin, N.S.R. 1998. Bathymetric distribution, biomass and growthdynamics of intertidal Phyllospadix scouleri and Phyllospadix torreyi in Baja California (Mexico). Marine Ecology Progress Series 173: 13-23.

Ramirez-Garcia, P., Terrados, J., Ramos, F., Lot, A., Ocana, D. and Duarte, C.M. 2002. Distribution and nutrient limitation of surfgrass, Phyllospadix scouleri and Phyllospadix torreyi, along the Pacific coast of Baja California (Mexico). Aquatic Botany 74: 121-131.

Turner, T. 1985. Stability of rocky intertidal surfgrass beds: persistence, preemption, and recovery. Ecology 66(1): 83-92.

Citation: Short, F.T., Carruthers, T.J.R., Waycott, M., Kendrick, G.A., Fourqurean, J.W., Callabine, A., Kenworthy, W.J. & Dennison, W.C. 2010. Phyllospadix scouleri. The IUCN Red List of Threatened Species 2010: e.T173367A7000726. . Downloaded on 21 June 2018.
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