State Route 58 Widening Project - Bakersfield Freeways

Chapter 4 Results: Biological Resources, Discussion of Impacts and Mitigation
Indirect Effects
Following project completion, there could be an unintentional increase in kit fox
vehicle strike in the action area. Vehicular strike is the primary source of mortality
among kit foxes in Bakersfield (Cypher 2000, Bjurlin et al. 2005) and has been found
to occur most frequently where kit foxes are abundant, on major arterial roads with
relatively high traffic volumes, and at intersections (Bjurlin et al. 2005). Currently,
the San Joaquin kit fox is exposed to the traffic along SR-58. Crossing additional
lanes may result in an increase in road kill mortality.
The construction of the proposed project could result in the displacement of kit foxes
and altered space use patterns, such as a change in habitat use or daily movement
patterns, both of which could result in disrupted social ecology, reduced fertility,
pregnancy rates, prenatal survival, mortality, and reduced carrying capacity in the
vicinity of the BSA.
Effects Determination
Based on the analysis of the potential direct and indirect effects, it can be concluded
that the proposed project ‘may affect, likely to adversely affect’ the San Joaquin kit
fox.
To reduce the potential for adverse effects on San Joaquin kit fox that could occur
during ground disturbing activities, Caltrans is proposing to implement standard
Avoidance and Minimization Measures that were described previously in
Section 4.1.1.3. These measures include standard construction and operational
requirements, pre-activity surveys, den monitoring, worker environmental awareness
training, and construction monitoring that are in accordance with USFWS
Standardized Recommendations for Protection of the Endangered San Joaquin Kit
Fox Prior to or During Ground Disturbance (USFWS 2011) and are expected to
avoid or substantially reduce the potential for adverse effects on kit fox such as den
loss and disturbance during construction activities.
Caltrans is also proposing to implement additional conservation measures beyond
those described for the standard Avoidance and Minimization Measures that would
further offset the potential adverse effects and also compensate for effects to habitat
that would result from the proposed project. As described in the following section
(4.1.1.5., see Onsite Mitigation through Project Design Modifications), Caltrans is
proposing to incorporate elements into the road design that are intended to facilitate
safe movement by kit foxes and substantially reduce adverse direct effects associated
36 State Route 58 Widening Project Biological Assessment