Chapters 1 - U.S. Fish and Wildlife Service

Chapter 4
acres within the Refuge support habitats historically found along the southern California coast,
with much of the site falling under the estuarine intertidal or estuarine subtidal habitat
classification per the National Wetlands Inventory (USFWS 2009). As indicated in Figure 4-13,
approximately 740 acres within the Refuge are subject to regular, unobstructed tidal influence,
supporting 565 acres of coastal salt marsh vegetation, 60 acres of intertidal mudflats, and 115 acres
of tidal channels and open water. Another 160 acres of the Refuge have been restored, providing a
combination of coastal salt marsh, mudflat, and subtidal habitats. Although these restored areas
are subject to regular tidal flushing, the tidal regime within these areas is muted. The remaining
+65 acres of the Refuge have either been developed or support disturbed upland habitat consisting
primarily of non-native grasses and weeds. The approximate acreage of each habitat type
occurring on the Refuge is presented in Table 4-5. A partial list of the plant species present on the
Refuge is provided in Appendix F.
Table 4-5
Summary of the Habitat Types Occurring on the Seal Beach NWR
Habitat Type Approximate Acres
Subtidal
Eelgrass present
No eelgrass
4-42 Seal Beach National Wildlife Refuge
95
166
Intertidal mudflat 52
Intertidal salt marsh 565
Tern nesting island 3
Restored Upland (coastal sage scrub) 5
Disturbed Upland 34
Developed (roads, structures) 45
TOTAL ACREAGE 965
4.3.3.1 Shallow Subtidal Habitat
The muted tidal regimes within the Refuge’s four tidal basins (i.e., Forrestal Pond, Case Road
Pond, 7 th Street Pond, and Perimeter Pond) support large areas of continually submerged, shallow
subtidal habitat. These ponds were created in the early 1990s as mitigation for the Port of Long
Beach’s Pier J Landfill project. In total, 116 acres of wetland habitat was restored within the
Refuge as a result of this project. Tidal waters from Anaheim Bay enter and exit the restored
ponds via constructed channels and culverts that pass under the surrounding roadways. The
largest of these culverts are located to the east of the intersection of Kitts Highway and Bolsa
Avenue, under the railroad tracks paralleling Forrestal Avenue, and at the southeast corner of the
7 th Street Pond. The 14.4-acre Forrestal Pond, which is surrounded on three sides by roads, and
the 7.5-acre Perimeter Pond, which is surrounded on all sides by salt marsh habitat, each support
predominantly shallow subtidal habitat. The other two ponds, the 52.4-acre Case Road Pond and
the 41.3-acre 7 th Street Pond, in addition to supporting shallow, subtidal habitat, also include
islands mostly comprised of salt marsh habitat. Additional areas of shallow subtidal habitat occur
at the southern most ends of the three major tidal arms that extend from the main channel that
connects the marsh to the ocean through the inner and outer harbors (refer to Figure 4-13).
Eelgrass (Zostera marina), a type of seagrass, occurs in various locations throughout the Refuge’s
subtidal habitat, including some of the subtidal channels and all of the mitigation ponds (refer to
Figure 4 -13). Eelgrass beds provide microhabitats for a wide variety of invertebrates and small
fishes, and provide important foraging areas for black brant and other types of waterfowl. The