appendix b final 2008 biological surveys of los angeles and long ...

9.0 Birds
Angeles Harbor. The relatively higher percent contribution of Western Gulls in recent studies
likely relate to the fact that the surveys encompassed both inner and outer harbor habitats, both
of which are used by the species.
The HEP (1979) study suggested that the increased breeding success of Brown Pelicans after
the ban on DDT discharges may have influenced the increase in Brown Pelicans counted in the
harbors between the early and late 1970s surveys. The number of Brown Pelicans has
remained relatively high since then. Although the percent contribution of Brown Pelicans to the
total bird counts has been somewhat less in recent surveys, that result is attributable to
differences in survey methodology compared to studies conducted in the 1980s. Because
Brown Pelicans mainly occur in the outer harbor, inclusion of the inner harbor in the total count
data of the 2000–2001 and current surveys contributes to a dilution of the percent contribution
calculation for that species compared to studies that only surveyed the outer harbor.
The percent composition of terns (most notably the Elegant Tern) increased in 2000–2001 over
previous surveys due to Elegant Tern nesting at Pier 400 (see Section 9.4.2). Elegant Terns
nested once again in 2008 after a two-year hiatus, although their nesting location was different
(see Section 9.4.2). Although nest numbers were similar to those during the 2000–2001
surveys (Table 9.4-3), the contribution of Elegant Tern decreased from approximately 10% in
2000–2001 to 7% in 2007–2008 (Table 9.6-1). This small reduction was likely associated with
the slight increase in the total birds counted per survey during the current study.
The percent contribution of Brandt’s Cormorants has increased over time, including a
substantial increase from approximately 5% in 2000–2001to 14% in 2007–2008. This increase
was due to their nesting in Zone 23 at the Long Beach West Basin during the current study.
The percent contribution of Double-crested Cormorants is comparable to previous surveys.
Surf scoter relative abundance has varied among surveys. During the 2000–2001 surveys, the
Surf Scoter showed a dramatic decline in percent contribution compared to previous surveys,
which MEC (2002) suggested was possibly related to dredging activity in the Ports. During the
2007–2008 surveys, the percent contribution of Surf Scoters increased by nearly four-fold, from
3% to 11%, with most individuals observed in Zone 23 (Long Beach West Basin). Because
dredging was ongoing in the West Basin and in other outer harbor areas during the 2000–2001
surveys, the relatively high abundance of Surf Scoters in the current study suggest that any
potential dredging effects were not persistent.
Western Grebes increased from approximately 5% of total observations during 1986–1987
surveys to 8% during 2000–2001 and 2007–2008 surveys (Table 9.6-1), likely due, at least in
part, to the addition of inner harbor stations in the recent studies.
Rock Dove accounted for approximately 5% of total birds during the 2000–2001 and 2007–2008
surveys (Table 9.6-1). Rock doves were most numerous on docks of the inner harbor (Table
9.5-2), presumably due to suitable roosting and nesting locations under the piers.
2008 Biological Surveys of Los Angeles and Long Beach Harbors 9–13
April 2010