Aerial view of Abbotts Lagoon

Dune Restoration in the Seashore

Dunes are dynamic interfaces between the land and the sea. From afar, they appear somewhat barren landscapes of seemingly endless undulating mounds of sand, but, in reality, they teem with life. The ecologically precarious western snowy plovers (Charadrius alexandrinus var. nivosus), listed as federally threatened species, nest at the oceanward edge of dunes, moving further inland at times for foraging. Federally threatened California red-legged frogs (Rana aurora draytonii) breed in the swale wetlands that form within interdune depressions in this otherwise seemingly arid landscape. Rare butterflies such as myrtle’s silverspot (Speyeria zerene myrtleae) forage on delicate violets and other vegetation within their midst. All in all, this unique habitat supports 11 federally listed plant and animal species.

Unfortunately, as with many other unique habitats in California and the coast of the U.S., dunes have been tremendously impacted. Homes and businesses have been built to the edge of the sea. Where dunes remain, they have often been artificially stabilized by vegetation and fencing to prevent migration and impact to adjacent homes, businesses, farms, and ranches. Many of the plants brought in to stabilize dunes come from elsewhere and, once introduced, these non-native species spread rapidly, slowly encroaching into and eventually ousting the native plant species adapted to this environment—many of which have subsequently become threatened and endangered. Some of the most common species planted to stabilize dunes are European beach grass (Ammophila arenaria), and iceplant (Carpobrotus spp).

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Not only do these non-native species displace rare and common native plant species, but, because most of these species form dense colonies, they actually retard the natural process of dune movement or migration. In natural communities, dunes continually move in response to wind pressure and wave action, typically forming morphologically and floristically distinct smaller foredune and slightly larger backdune communities. These dune systems are often characterized by relatively flat corridors between dunes that allow for movement of many animal species, including snowy plovers, and "slacks" or depressional basins where groundwater and precipitation form an aquatic oasis. Non-native species and their deep root and rhizome systems act to armor dune systems and prevent natural migration, which leads to overly large foredunes and backdunes, an impoverished native vegetation community, and a substantial decrease in value of this system to wildlife.

Some of the largest remnant dune systems in California can be found in Point Reyes National Seashore. There are approximately 16 miles of dunes along the Point Reyes Peninsula, Drakes, and Limantour coastlines. In addition, the Seashore has one of the largest remaining breeding populations for the plover, which, based on statewide numbers, is in imminent danger of extinction. However, the Seashore’s dunes are threatened by continued encroachment of European beachgrass and iceplant, which were planted decades ago to stabilize these systems.

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Dune Habitat at Abbotts Lagoon showing native vegetation in the foreground and dunes dominated by non-native European beachgrass in the background.

For this reason, the Seashore is embarking on an active program of restoration for its dune systems. Since 2002, it has been conducting a number of small-scale removal projects near Abbotts Lagoon that have been focused on mechanical removal with limited spot spraying of resprouts. Initial results have been encouraging. While dunegrass has resprouted, its density has been reduced, and the cover of native plant species, including some federally threatened and endangered species such as Tidestrom’s lupine (Lupinus tidestromii), has more than dramatically increased (Peterson 2005). In addition, these efforts have seemingly encouraged some restoration of more natural contours through redistribution of sand in the formerly Ammophila-armored dunes.

Based on these promising results, the Seashore is embarking on a more ambitious program of removal just south of Abbotts Lagoon to remove more than 130 acres of European beachgrass from a 300-acre Project Area. This project, which is still in the planning stages, would possibly start in 2010. The Seashore is currently releasing the draft Environmental Assessment for public review (see below). In future years, the Seashore hopes to expand its restoration program southward along the Great Beach and on the dunes that border Drake’s and Limantour Esteros.

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EA Now Available for Abbotts Lagoon Dune Restoration Project

The Seashore has released the Abbotts Lagoon Area, Dune Restoration Plan and Environment Assessment (EA) (4,607 KB PDF), which focuses on improving and restoring coastal dune habitat directly south of Abbotts Lagoon, for public review.

Part of project planning is the examination of environmental impacts through the National Environmental Policy Act (NEPA) process. Because no significant impacts are expected to occur, the Seashore has prepared an environmental assessment, rather than an environmental impact statement.

In the National Park Service, the public is asked to comment on the EA or any other aspect of the proposal in an early 45-day comment period. Your comments can be submitted through the NPS Planning, Environment and Public Comment (PEPC) website, or in writing via fax or letter. The PEPC website is http://parkplanning.nps.gov/. Letters should be addressed to: Superintendent:

Coastal Dune Restoration Project
Point Reyes National Seashore
1 Bear Valley Road
Point Reyes Station, CA 94956

You may also fax your comments to 415-663-8132, or you may email your comments. Your comments will be most helpful to us if we receive them no later than March 20, 2009.

In addition, to facilitate public input, the Seashore held a public information meeting on Wednesday, March 11, at 6:00 p.m. in the Red Barn.

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Options for treating different subsets of the 300-acre project area now slated for Ammophila removal were initially developed after public scoping and refined using value analysis. Alternatives presented in the project EA evaluate different approaches to achieving restoration within the 300-acre project area. Alternative C would achieve restoration objectives using mechanical excavation treatments with potential re-treatment of resprouts with minimal use of herbicides through spot spraying of herbicides, and Alternative B that would treat all 300 acres using use a combination of treatment methods including fire and herbicides in addition to mechanical excavation. Alternative A is the No Action Alternative and would continue the present program of small-scale eradication projects.

The preferred alternative is Alternative C, which emphasizes Mechanical Control Methods. The preferred alternative was selected after initial assessment and comparison of the potential impacts associated with four alternatives. Both Alternatives B and C would equally improve the condition of resources in the long term, but Alternative C would have fewer adverse impacts and therefore result in less loss of resource during implementation. Cost was considered as well, but was secondary to the alternative’s ability to meet the primary objective of resource protection.

Previous work on experimental plots in the Seashore and elsewhere have indicated that the most effective treatment to restore dunes where these invasive species exist is to remove all biomass and bury it deep under a cap of clean sand. This requires the use of heavy motorized equipment. Small scale hand removal to protect resources (where Ammophila is interspersed with wetland or rare vegetation for example) and the minimal use of herbicides to minimize resprouts would also occur. (Herbicide is being included as a potential retreatment option, because other projects have demonstrated that Ammophila removal is not as effective without some use of herbicide.) Small experimental burns are also possible.

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Any restoration work would be accomplished within the constraints imposed by laws, policies and sound management practices including environmental protection measures. For example, no heavy equipment would be used within 500 feet of where snowy plovers are nesting, and surveys and flagging would prevent impacts from excavators to sensitive plant and animal species. In addition, a minimal amount of herbicides would be used only in selected areas with protective buffers established adjacent to wetlands, rare plants, nesting areas, and adjacent land uses and would involve only a very controlled application of herbicide directly to resprouts.

Consultation on potential impacts on to listed special status species will be conducted with the US Fish and Wildlife Service. In addition, because the project area is located within the coastal zone, and will result in modification to wetland resources, the project will also require review of by, and permits from the San Francisco Bay Regional Water Quality Control Board, US Army Corps of Engineers, and federal consistency review by the California Coastal Commission.

Please note that names and addresses of people who comment become part of the public record. If you wish to withhold your name and or address from the public record for this project, you must state your request prominently at the beginning of your comments. Anonymous comments may not be considered. We will make all submissions from organizations, businesses, and from individuals who identify themselves as representatives or officials of organizations or businesses available for public inspection in their entirety. Individuals not representing business or organizations may request that the NPS withhold their name and/or address from the record.

Abbotts Lagoon Area Dune Restoration Plan Environmental Assessment – January 2009 (4,607 KB PDF)

Letter to Interested Parties - February 9, 2009 (43 KB PDF)

Restore Critical Dune Habitat Flyer - October 14, 2005 (220 KB PDF)

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