Chapters 1 - U.S. Fish and Wildlife Service

Chapter 4
following a period of significant rainfall in late 2004 and early 2005. The increased height and vigor
of the cordgrass was noted on November 15, 2005 when a significant amount of protruding
cordgrass cover was visible during an extremely high 6.7-foot tide.
Middle marsh, or marsh plain, is typically characterized by the presence of saltwort and
pickleweed. Other species identified in the upper portion of the pickleweed zone include arrow
grass (Triglochin concinna) and Jaumea (Jaumea carnosa) (Baker in Lane and Hill 1975). At
Anaheim Bay, middle marsh species are found at the outer edge of the marsh, with no clear line of
demarcation between these species and cordgrass (CDFG and USFWS 1976).
The upper zone of salt marsh habitat lies above the mean high tide line and is flooded only during
the highest spring tides. Dominant plants include glasswort and pickleweed, with a variety of
other plant species also present including alkali heath, estuary seablite, alkali weed, salt grass, sea
lavender, and shore grass. Within those portions of Anaheim Bay that are subject to full tidal
flushing, high marsh habitat is limited to narrow strips of land located along the edges of the road
fills and old berms. High marsh habitat also occurs in portions of Case Road Pond, around the
edges of some of the islands present in 7 th Street Pond, and in the Bolsa Cell, located to the north
of Bolsa Avenue. The muted tidal regime in this area isolates the salt marsh habitat from full tidal
influence, supporting dense stands of pickleweed.
The highest elevations of the high marsh zone are often referred to as wetland/upland transition or
upland transition marsh. This habitat zone is not considered a distinct community; rather it
represents a gradient between the upper marsh and the native upland habitats of coastal sage
scrub and maritime succulent scrub. Unfortunately, no remnants of historical upland transition
habitat remain around Anaheim Bay. Some areas adjacent to the marsh habitat do support a few
native species, but for the most part, these areas are dominated by non-native weeds and grasses.
Other areas have been planted with native upland species in an effort to create a more natural
wetland/upland transition zone.
4.3.3.4 Upland Habitat
The Refuge contains about 65 acres of uplands, most of which were historically wetlands that were
filled during the last century to support a variety of uses associate primarily with military and
agricultural activities. Approximately 41 acres of these uplands have been developed to support
roads, berms, railroad tracks, and other structures associated with past or current operations on
NWSSB. The remaining undeveloped uplands consist of non-native grasslands, natural and manmade
islands, and native shrub revegetation areas.
The only area within the Refuge that historically supported native upland vegetation is Hog Island,
located in the southern portion of the Refuge. None of the original native vegetation exists on Hog
Island today, and the area referred to as Hog Island is actually larger today than it was in the past.
Only about one acre at the center of present day Hog Island is actually part of the original natural
upland island. The three “arms” that extend out from the island consist of fill material placed
there to support past military uses. These “arms” were recently planted with native vegetation to
support uplands birds, as well as to provide cover for shorebirds and other waterbirds during high
tides.
Another upland area within the marsh is NASA Island. This 2.9-acre island is man-made and was
constructed for rocket testing in the mid 1960s. It was used for this purpose until about 1977, when
the site was turned over to the Service for conversion to a nesting site for the California least tern
(USFWS 1985). To make the site suitable for nesting, the area was leveled and portions of the site
4-46 Seal Beach National Wildlife Refuge