Chapters 1 - U.S. Fish and Wildlife Service

Chapter 5
impacts on nontarget species.” Kwan et al. (2009) reported similar results in a study conducted in
2007, and concluded that a considerable number of small-bodied insects are killed as a result of a
single application of ultra-low volume pyrethrins; however, the effect is short lived at the
population level. Another study conducted at some seasonal ponds on the Sutter NWR found that
although there was a decrease in the number of flying insects following application of adulticides,
including pyrethrin, the numbers rebounded within 48 hours (Jensen et al. 1999). Although these
studies looked at the effects of various adulticides, they did not include the use of phenothrin.
However, phenothrin is a synthetic form of pyrethrin; therefore, the outcomes would be expected
to be similar.
Although the application of ultra-low volume adulticides can result in the loss of significant
numbers of non-target insects within and surrounding a treatment area, it appears from the
literature that the effects would be localized and temporary in nature. The anticipated limited use
of ultra-low volume adulticide application on the Refuge is expected to be very infrequent and use
will be limited to specific locations and under specific meteorological conditions; all of which will
further reduce the potential for significant adverse effects on terrestrial invertebrates.
Public Use
As no new public use opportunities are proposed under Alternative B, the effects to insects,
reptiles, and amphibians would be the same as those described for Alternative A.
5.4.2.5 Effects to Mammals
Wildlife and Habitat Management
Under Alternative B, all of the actions described in Alternative A would also be implemented.
Therefore, the effects to mammal as a result of implementing these specific actions, including
predator management, would be the same as those described above for Alternative A.
Impacts to land mammals would be similar to those described for landbirds in that upland habitat
would be converted to wetland and transitional habitat resulting in the loss of habitat to support
upland oriented species. The mammalian species that occur on the Refuge also occur on the
adjacent uplands of NWSSB, as well as along the edges of the marsh, therefore, some habitat to
support these species will continue to be present on the Refuge. Because the population of
mammals on the Refuge is small and no special status or sensitive species are supported
exclusively on the Refuge, the loss of upland habitat would not represent a significant adverse
impact to mammals.
Avoidance of significant adverse effects to seals and sea lions that occasionally enter the Refuge
through the larger tidal channels that extend to Perimeter Pond and 7 th Street Pond would occur
through the implementation of measures similar to those described to protect sea turtles during
construction and culvert replacement. These measures include conducting presence/absence
surveys prior to construction, monitoring for these species during construction, and installing
appropriate barriers, as appropriate, to keep these species out of the restoration areas during
construction.
Pest Management
Implementation of the IPM Plan for the Refuge (Appendix C), as described above, would ensure
that no adverse effects to the Refuge’s mammals would occur as a result of the use of pesticides.
The pesticides proposed for use under this alternative to control mosquitoes are not expected to
adversely affect mammalian species supported on the Refuge. Spinosad is relatively low in toxicity
5-50 Seal Beach National Wildlife Refuge