Spread of Exotic Cordgrasses and Hybrids (Spartina sp.) in the Tidal Marshes of San Francisco Bay, California, USA

  title={Spread of Exotic Cordgrasses and Hybrids (Spartina sp.) in the Tidal Marshes of San Francisco Bay, California, USA},
  author={Debra R. Ayres and Debra L. Smith and Katherine Zaremba and S Klohr and Donald R. Strong},
  journal={Biological Invasions},
Four species of exotic cordgrass (Spartina sp.) occur in the San Francisco estuary in addition to the California native Spartina foliosa. Our goal was to map the location and extent of all non-native Spartina in the estuary. Hybrids of S. alterniflora and S. foliosa are by far the most numerous exotic and are spreading rapidly. Radiating from sites of deliberate introduction, S. alterniflora and hybrids now cover ca. 190 ha, mainly in the South and Central Bay. Estimates of rate of aerial… 
Responses to salinity of Spartina hybrids formed in San Francisco Bay, California (S. alterniflora × foliosa and S.densiflora × foliosa)
The results imply that mid-zone marshes in SFB are also vulnerable to invasion by salinity-tolerant Spartina hybrids, and efforts in monitoring and management of exotic Spartina and its hybrids must continue as vast areas of tidal marsh restoration are underway and planned.
Salt Marsh Claviceps purpurea in Native and Invaded Spartina Marshes in Northern California.
Under field conditions, S. foliosa sustained a higher incidence of disease in coastal marshes than in marshes within the bay, which may be attributable to environmental differences between the coast and the bay proper, with the former being more conducive to infection by C. purpurea.
Changes in the population genetics of an invasive Spartina after 10 years of management
Investigating changes in the population genetics of the invasion of invasive Spartina after 10 years of eradication efforts and after three subsequent years without eradication in some locations supported previous descriptions of a system of self-fertile hybrid plants that supply seed for mostly localized recruitment into available habitat.
Impact of invasive Spartina alterniflora on song sparrow and marsh wren populations in San Francisco Bay salt marshes
An exotic cordgrass, Spartina alterniflora, is altering the vegetative structure and composition of the San Francisco Bay tidal marsh ecosystem, which has multiple impacts on the Alameda song sparrow
Sexual reproduction of cordgrass hybrids (Spartina foliosa x alterniflora) invading tidal marshes in San Francisco Bay
Cordgrass plants and seedlings throughout the San Francisco, California, USA, estuary are genetically analysed and it is found that hybrids between exotic Spartina alterniflora and native Spartina foliosa are the principal cordgrass invaders and colonizers.
Hybridization between invasive Spartina densiflora (Poaceae) and native S. foliosa in San Francisco Bay, California, USA.
The existence of a third recent Spartina hybridization, discovered in 2002, between introduced S. densiflora and native S. foliosa is reported, indicating that several avenues existed that may have given rise to a new allopolyploid species.
Extinction of a Common Native Species by Hybridization with an Invasive Congener1
The introduction of smooth cordgrass, a tidal marsh grass native to the Atlantic, into the range of California cordgrass in San Francisco Bay, CA, in the 1970s resulted in the loss of existing native cordgrass plants and the usurpation of cordgrass regeneration sites by copious hybrid seed.
Potential Ocean Dispersal of Cordgrass (Spartina spp.) from Core Infestations
The recovery patterns of drift cards, released monthly over the course of 1 yr underscore increased propagule loading at areas proximal to existing infestations, but also highlight the ability of ocean currents to carry seeds great distances, well within known propagule viability ranges.
Native and Introduced Ecosystem Engineers Produce Contrasting Effects on Estuarine Infaunal Communities
This study compared vegetation, sediment structure, and infaunal invertebrates in native and invaded marshes in San Francisco Bay and suggests that these two closely related species both act as ecosystem engineers, but with opposing effects on invertebrate communities.
Benthic macrofaunal communities of three sites in San Francisco Bay invaded by hybrid Spartina, with comparison to uninvaded habitats
It is suggested that the invasive Spartina hybrid in south San Francisco Bay can have differing effects on sediment ecosystems, possibly depending on the location, age, or type of habitats involved.


The introduction and spread of smooth cordgrass (Spartina alterniflora) in South San Francisco Bay
Spartina alterniflora has a wider intertidal distribution than S. foliosa and outproduced the native cordgrass in all aspects that were studied, and once established, it spreads more rapidly vegetatively than the native species.
Extent and degree of hybridization between exotic (Spartina alterniflora) and native (S. foliosa) cordgrass (Poaceae) in California, USA determined by random amplified polymorphic DNA (RAPDs)
The spread of S. alterniflora and S. foliosa × altern iflora hybrids in California was determined and the degree of hybridization examined and the proliferation of cordgrass hybrids could grossly alter the character of the San Francisco Bay was examined.
Spartina (Gramineae) in northern California: distribution and taxonomic notes
Morphological and ecological data support the conclusion that the species occurring in Humboldt Bay should be referred to as Spartina densiflora and was probably introduced to northern California from South America during the mid-nineteenth century.
Hybridization between introduced smooth cordgrass (Spartina alterniflora; Poaceae) and native California cordgrass (S. foliosa) in San Francisco Bay, California, USA.
Introduced Spartina alterniflora (smooth cordgrass) is rapidly invading intertidal mudflats in San Francisco Bay, California. At several sites, S. alterniflora co-occurs with native S. foliosa
Mechanisms of expansion for an introduced species of cordgrass, Spartina densiflora, in Humboldt Bay, California
Findings indicate that S. densiflora expands primarily by vegetative expansion, and lateral tillers are produced by throughout the year, but recruitment in mature salt marshes may be limited by competitors and higher salinities.
Evolution of a new ecotype of Spartina alterniflora (Poaceae) in San Francisco Bay, California, USA.
The absence of S. patens from most of San Francisco Bay has allowed the dwarf ecotype of smooth cordgrass to survive and spread, and it is suggested that the ecological range of the dwarf smooth Cordgrass ecotype is similar to that of S .
Spartina patens as a weed in Galician saltmarshes (NW Iberian Peninsula)
Spartina patens (Gramineae) is an American coastal grass which grows in a wide range of coastal habitats in its native area. After it was discovered in some Galician wetlands two years ago, we
Lower limits of Spartina densiflora and S. maritima in a Mediterranean salt marsh determined by different ecophysiological tolerances
Lower limits to the fundamental niches of the two species in a Mediterranean-type salt marsh are defined and thus provide a basis for future investigations of interactions between them.
Reciprocal hybrid formation of Spartina in San Francisco Bay
The most significant finding was that hybridization proceeds in both directions, assuming maternal inheritance of cpDNA; 26 of the 36 hybrid Spartina plants from San Francisco Bay contained the S. foliosa haplotype, nine contained haplotypes of the invading S. alterniflora, and one had the cpDNA of unknown origin.