CarlsbadHSCorridorReport Final April 2010 · College and Cannon Carlsbad High School Site Wildlife Movement Study 6552-01 1 April 2010 1.0 INTRODUCTION The Carlsbad Unified School

College and Cannon Carlsbad High School Site Wildlife Movement Study

Prepared for:

Carlsbad Unified School District 6225 El Camino Real

Carlsbad, California 92009

Prepared by:

605 Third Street

Encinitas, California 92024 Contact: Mike Howard

APRIL 2010

Printed on 30% post-consumer recycled material.


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TABLE OF CONTENTS

Section Page No.

1.0 INTRODUCTION..............................................................................................................1 1.1 Wildlife Habitat Connectivity Primer..................................................................... 1

2.0 PROJECT SETTING ......................................................................................................14

3.0 METHODS AND SURVEY CONDITIONS .................................................................14 3.1 Literature Review.................................................................................................. 14 3.2 Field Reconnaissance............................................................................................ 16

3.2.1 Road-kill Survey ....................................................................................... 16 3.2.2 Track Survey............................................................................................. 19 3.2.3 Camera Study............................................................................................ 19

3.3 Survey Limitations................................................................................................ 20

4.0 RESULTS OF SURVEYS ...............................................................................................29 4.1 Road-Kill Survey .................................................................................................. 29 4.2 Track Surveys ....................................................................................................... 30

4.2.1 Scent Station Surveys ............................................................................... 30 4.2.2 Trail Surveys............................................................................................. 31

4.3 Camera Study........................................................................................................ 33 4.4 Special-status Biological Resources ..................................................................... 33

4.4.1 Special-status Wildlife .............................................................................. 33 4.4.2 Wildlife Corridors and Habitat Linkages.................................................. 34

5.0 DISCUSSION ...................................................................................................................41

6.0 LITERATURE CITED ...................................................................................................51

APPENDIX

List of Wildlife Observed Within Study Area


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LIST OF FIGURES

Figure 1 Regional Map...........................................................................................................3 Figure 2 Vicinity Map ............................................................................................................5 Figure 3 Project Overview Map .............................................................................................7 Figure 4 Road-Kill Survey Area ..........................................................................................17 Figure 5 Track Surveys – Scent Station Locations ..............................................................21 Figure 6 Track Survey – Trail Overview and Species Locations.........................................23 Figure 7 CNLM Conservation Area.....................................................................................25 Figure 8 Camera Locations ..................................................................................................27 Figure 9A Cameras 1 & 5 Wildlife Photographs ....................................................................35 Figure 9B Camera 5 Wildlife Photographs.............................................................................37 Figure 10 Wildlife Movement and Barriers ..........................................................................39 Figure 11 Linkage Constraint Levels .....................................................................................47 Figure 12 Recommendations for Wildlife Movement Facilitation and

Improvements ........................................................................................................49

LIST OF TABLES

1 Crossing Structure Type and Size: Recommendations for Different Species ...................12 2 Road-kill Survey Results ...................................................................................................29 3 Scent Station Survey Results .............................................................................................30 4 Camera Survey Results ......................................................................................................33 5 Potential Wildlife Connections Within the Study Area.....................................................41


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1.0 INTRODUCTION

The Carlsbad Unified School District is planning to construct a new high school at the corner of College Boulevard and Cannon Road in Carlsbad, California (Figures 1, 2, and 3). The proposed location for the new high school is adjacent to the Calavera Conservation Area, a recreational open space and core habitat area located within the City of Carlsbad. This is adjacent to Calavera Hills & Robertson Ranch Habitat Conservation Area (Conservation Area) managed by the Center for Natural Lands Management (CNLM; Figure 3). Additionally, there is an extension of Cannon Road planned in the same vicinity. Carlsbad Unified School District is interested in wildlife movement in the area. The proposed project is located within and adjacent to a large block of undeveloped lands and is surrounded by a network of open lands that occur between neighborhoods and developments in the vicinity. These areas potentially support wildlife movement to other connected lands to the west (Agua Hedionda, Buena Vista, and Batiquitos Lagoons), north (Oceanside habitat blocks), and southeast (Elfin Forest and Lake Hodges), and other lands to the east. Dudek was contracted to perform a variety of wildlife movement methods during a three-week period in January/February 2010, to identify wildlife movement and related issues. This report describes the results of the wildlife movement study conducted for the proposed project area, surrounding open space and roadways. The purpose of the wildlife movement study was to determine what wildlife species are utilizing the area, where movement is occurring and the potential impact to wildlife from existing and proposed land uses.

1.1 Wildlife Habitat Connectivity Primer

A fundamental concept and central tenet of conservation biology theory is that a lack of habitat connectivity and contiguity (usually referred to as habitat fragmentation and isolation) may cause extinction of local populations as a result of two processes: (1) reduction in total habitat area, which reduces effective population sizes; and (2) insularization of local populations, which affects dispersal and immigration rates (Wilcox and Murphy 1985; Wilcove et al. 1986). Wilcox and Murphy (1985) further point out that immigration may be impeded by conversion of natural vegetation communities that provide habitat between occupied or potential habitat patches, thus increasing the probability of extinction. This latter point is the crux of the habitat linkage problem. That is, isolation of habitat patches accompanied by intervening inhospitable land cover (e.g., urban development, roadways) is thought to increase the probability of permanent extinction of local populations. Because of complex community-level interactions (e.g., mutualistic species, habitat guilds, keystone species), the loss of one or a few species from a habitat patch as a direct result of habitat fragmentation (primary extinctions) may also result in multiple "secondary" extinctions within the habitat patch (Wilcox and Murphy 1985).


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Habitat fragmentation has been linked with reduced diversity in bird species, even on adjacent nonfragmented habitats (Rottenborn 1999). Several studies in coastal San Diego County have demonstrated species losses related to habitat fragmentation and isolation. Soulé et al. (1988) found very high rates of extinction in a study of the distribution of "chaparral-dependent" native birds (the analysis included coastal sage scrub species) in isolated canyon habitat fragments. Soulé et al. (1988) attributed this loss to the focal species' generally low vagility and inability to traverse urban environments. Similarly, Soulé et al. (1992) found that fragmentation caused rapid extinctions with predictable sequences of species loss in a suite of species including plants, birds, and rodents in coastal sage scrub habitat. Bolger et al. (1997) found fewer rodent species in fragments isolated for longer periods of time and at greater isolation distances in coastal San Diego County. Lower arthropod diversity was also observed by Bolger et al. (2000) in older and smaller habitat fragments in the same region.

Wildlife connections also likely play a critical role in sustaining "metapopulations," which are characterized as local populations of the same species that are partially isolated but connected by pathways for dispersal (immigration/emigration) (Levins 1969). Local populations within a metapopulation are subject to stochastic events, and they fluctuate depending on the rate of dispersal between the local populations and the local rate of extinction. Patches subject to local extirpations may be recolonized by dispersal from other source patches, provided that habitat connectivity remains for the species. Truly or functionally isolated local populations risk permanent extinction by a variety of causes, including simple population dynamics, loss of genetic integrity, or stochastic environmental impacts.

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FIGURE 1

Regional Map6552-01

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FIGURE 2

Vicinity Map6552-01

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SOURCE: USGS 7.5 Minute Series San Luis Rey Quadrangle.

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FIGURE 3

Project Overview Map

College and Cannon High School Project Wildlife Movement Study

SOURCE: SanGIS, 2008; DigitalGlobe, 2008

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Natural environments are typically heterogeneous and form a mosaic across a landscape. Plant community distributions, in particular, follow distinct patterns based on abiotic conditions (e.g., soil, slope aspect, elevation) and biotic conditions (e.g., competition, soil microbial ecology, parasitism). Terrestrial wildlife species typically occupy favorable patches within a landscape matrix and may move between patches through less favorable habitats. However, terrestrial wildlife species are more likely to follow pathways between habitat patches that contain elements of their preferred habitat (Rosenberg et al. 1997). Disjunct habitat patches that are used by terrestrial wildlife to negotiate through landscape mosaics have been likened to "stepping-stones," and some researchers (e.g., Bennet 2003) have suggested that, in some cases and for some species, stepping-stone habitat is as effective as continuous corridors are. However, such stepping-stone patches must be traversable and must not be behaviorally limiting to the species. Behavior has been shown to be a primary condition that determines the propensity of a particular species to utilize a habitat linkage or corridor. Such limitations include movement behavior, environmental cues (e.g., olfactory cues), perceived risk of predation, susceptibility to disturbance, and human activity (e.g., Aars and Ims 1999; Brinkerhoff et al. 2005; Fernandez-Juricic et al. 2005). For example, individuals may traverse relatively long distances across generally unsuitable but natural habitat, but behaviorally will avoid crossing paved and unpaved roads (see Trombulak and Frissell 2000 for a review of the ecological effects of roads). Therefore, for a habitat linkage or corridor to function properly, it must not pose physical or behavioral obstacles to the movement behavior of a particular species. Additionally, the rate of animal movement through a landscape matrix may depend on the quality of habitat for that species (Rosenberg et al. 1997). Terrestrial wildlife tend to move more slowly through areas with higher-quality habitat components than through those areas with lower-quality habitat components. Risk of predation, disturbance, and human activity are also limiting factors for species movement and dispersal.

There is a distinction between short-term individual movements (such as foraging within an organism's home range), long-term dispersal (one-time emigration and immigration events between populations), and migration (seasonal or periodic movements). Corridors and habitat linkages may allow for both long- or short-term movements, dispersal, and migration, depending on the life history requirements and the ability of a particular species to travel through a landscape (also called its vagility). The habitat requirements that allow for dispersal and migration likely are similar, the difference being that dispersal is usually a one-way movement related to emigration/immigration, and migration is a seasonal or periodic movement (Lincoln et al. 1998).


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Wildlife Landscape Habitat Linkages

Landscape habitat linkages (or simply linkages) are relatively large open space areas that contain natural habitat and provide connection between at least two larger adjacent open spaces that can provide for both diffusion and dispersal of many species. Linkages can form contiguous tracts of habitat when adjacent to other open space areas. Large open space networks can be formed in this way to connect and conserve habitat through entire regions (Bennett 2003).

Linkages can form large tracts of natural open space, serving both as "live-in" or "resident" habitat and as connections to the larger landscape (e.g., large core habitat areas). Linkages are capable of sustaining certain communities of species in self-contained, functioning ecosystems, thus supporting both plant and animal populations and allowing for gene flow through diffusion of populations over a period of generations, as well as allowing for jump dispersal between neighboring habitats. Linkages may vary in their function depending on the species, serving more as landscape-scale dispersal corridors than habitat for larger or more vagile species, particularly those with large home ranges such as mountain lions. Linkages are, nonetheless, capable of supporting at least a portion of the populations of these larger or more vagile species. Linkages may also serve as migratory routes for ungulates, for example, and thus provide a more natural and sustainable landscape environment for large predators and their prey compared to wildlife corridors through which species are expected to move quickly.

Wildlife Corridors

Rosenberg et al. (1995) distinguish between habitat and wildlife corridors. Habitat provides for the life history components of survivorship, reproduction, and movement. Wildlife corridors are linear landscape elements that provide for species movement and dispersal between two or more habitats but do not necessarily contain sufficient habitat for all life history requirements of a species, particularly reproduction (Rosenberg et al. 1995, 1997). For this reason, while corridors may provide for dispersal of most species, they may not provide for diffusion of populations over a longer time scale. The main prerequisite for corridors is that they increase animal movement between habitat patches. The mechanisms related to the efficacy of corridors are varied and species-specific (Soulé and Gilpin 1991; Beier and Loe 1992; Rosenberg et al. 1995; Haddad and Tewksbury 2005A). Additionally, even if the corridor itself does not provide habitat functions, it is expected to at least maintain plant and animal populations, gene flow between the constituent subpopulations, and biodiversity (Haddad 1999). This ebb and flow of genetic diversity should occur if organisms are traversing corridors that physically connect geographically patchy populations (Beier and Loe 1992). Corridors thus provide physical conduits for maintaining specific genetic diversity, species richness, and community integrity. However, corridors may also connect population sources to "sink habitat" that can result in the net reduction of a


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population; in other words, the sink habitat either does not support the full life history of the species, or populations are more vulnerable to risk factors.

Wildlife Crossings

Wildlife crossings are locations where wildlife must pass through physically constrained environments (e.g., roads, development) during movement within home ranges or during dispersal or migration between core areas of suitable habitat. Development and roads may transect or interrupt an existing natural crossing, creating dangerous or impassable barriers that impede the natural movement of a species and possibly expose it to higher risks of injury and mortality from adverse human interactions, such as increased vehicle collisions at roadways where no safe wildlife passage is provided (Meese et al. 2007).

When designing wildlife crossings, it is important to identify the natural passageways that target animals use to locate crossings. Often, artificial crossings are seldom used by wildlife when a more natural alternative or previously used crossings still exist. For example, Tull and Krausman (2001) found that, while 22% of radio-collared mule deer locations were in a designed crossing of a canal, there were indications that the deer crossed at other points along the canal. Tull and Krausman (2001) attributed the other crossings to the absence of significant urbanization along the canal and suggested that, as development encroached along the canal, the designed crossing would become more important.

Post-development drainages are typical pathways for wildlife movement across roads, although they are not the only pathways used. Structures where roads and drainages intersect are often constricted or confined in some way and provide funnel points for movement, such as road undercrossings, space beneath bridges, or pathways through large culverts. Wildlife crossings are used differently or at different frequencies, depending on the species and the conditions at the crossing. Although most existing structures, such as culverts or bridges under roads, were not originally designed to accommodate wildlife passage, they can be retrofit or redesigned to encourage wildlife use by restoring or maintaining native vegetation and "soft-bottom" natural substrates within the crossing, allowing natural lighting, using fences to guide larger species toward the crossing, locating crossings at pre-existing animal passages, and improving habitat adjacent to the crossing to provide cover and protection for wildlife (Carr et al. 2003; Meese et al. 2007). Some recommended design standards for different kinds of wildlife crossings are available from Ruediger and DiGiorgio (2007), as summarized in Table 1.


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Table 1 Crossing Structure Type and Size: Recommendations for Different Species1

Crossing Structure Round Culvert

Concrete Box Culvert

Multi-Plate Steel Arch

Open-Space Bridge, Bridge

Extension Overpass

Black bear 10'+ 10'+ h × 20'+ w 10'+ h × 20'+ w 10'+ h × 20'+ w 75'+ w Mountain lion 10'+ 10'+ h × 20'+ w 10'+ h × 20'+ w 10'+ h × 20'+ w 75'+ w Bobcat 48"+ 48"+ h × 48"+ w structures for larger

animals will be adequate for smaller animals

structures for larger animals will be adequate for smaller animals


Coyote 48"+ 48"+ h × 48"+ w structures for larger animals will be adequate for smaller animals



Small carnivores: badger, raccoon, skunk, weasel, and fox. Also accommodates smaller mammals, reptiles, and amphibians

36"+ 36"+ structures for larger animals will be adequate for smaller animals



Deer 10'+ 10'+ h × 20'+ w 10'+ h × 20'+ w 10'+ h × 20'+ w 75'+ w Key: Adequate for Passage Best for Passage 1 Adapted from Ruediger and DiGiorgio (2007). "Information in this table was established from current studies, including recommendations

from biologists and engineers with extensive wildlife crossing experience. This table is a general guide to designing and choosing appropriate structures for many target species. Other factors, such as terrain, engineering feasibility, cost, and site-specific conditions are always a consideration. The table is meant only as a broad guideline to assist in the selection of wildlife crossings." (Ruediger and DiGiorgio 2007).

Although there are some general recommendations for the dimensions of crossing structures, as shown in Table 1, the specific factors that contribute most to the effectiveness and design criteria of structures used as wildlife crossings, such as bridges and box culverts, are still under debate. Among these factors, in addition to structural dimensions, are the use of fencing, existing landscapes, proximity to natural habitat edges and water features, the probability of human disturbance, and the intended species. Views differ regarding the most effective placement of wildlife crossings and whether structural features or location and landscape features are more important in determining ultimate success.

Several studies have shown that structural dimensions beyond the height and width of the crossing and related factors play primary roles in the success of providing adequate wildlife crossings between habitat fragmented by roads and highways. Reed et al. (1975) found openness to be a significant factor in determining relative effectiveness of structures in terms of use by


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deer and other species. In this study, the openness factor (or index) was a structural variable used as a measurement of ambient light in a structure and was calculated by the following equation: width times height divided by length (in meters) (Reed et al. 1975). Later studies also applied the openness index as one measurement for the effectiveness of wildlife movement at highway underpasses. For example, Donaldson (2005) found that the length of a structure should be short enough to result in an openness factor of at least 0.25 to discourage white-tailed deer from turning around at structure crossings. This study also determined that effective underpasses were easily accessible with level approaches and had clear lines of site to habitats on the far side (Donaldson 2005). Another study determined that use of crossing structures by raccoons and domestic cats and dogs was positively correlated with passage length, while use by mule deer was negatively correlated with the same factor (Ng et al. 2004). The importance of structural dimensions has been illustrated for both large predator and prey species. In Banff National Park, structural dimensions, including openness and width, were determined to be most significant only for ungulates while playing a less significant attribute for carnivores (Clevenger and Waltho 2000). However, later studies indicated structural passage by grizzly bears, wolves, elk, and deer to be strongly influenced by wildlife crossings that were high, wide, and short in length, and that black bears and cougars favored more constricted crossing structures (Clevenger and Waltho 2003).

Others have argued against the ultimate value that structural dimensions hold with respect to wildlife crossings. Many studies have identified several other factors as the most significant in contributing to the effectiveness of crossing structures. Beier and Loe (1992) have emphasized that the critical features of a wildlife corridor are not physical traits, such as its length or width or vegetation, but rather how well a particular piece of land fulfills several functions, including allowing wide-ranging animals to travel, migrate, and meet mates; plant propagation; genetic interchange; movement of populations due to environmental changes and natural disasters; and allowing recolonization of habitats from which populations have been locally extirpated. Beier and Loe (1992) argue that these functions (rather than some minimum width) should be used to evaluate the suitability of land as a wildlife corridor. The Ng et al. (2004) study, discussed above, also identified correlations with several other factors. Coyote use of wildlife crossings showed a significant positive correlation with human activity and a negative correlation with developed habitat. For bobcats, the relationship between passage use and percentage of natural habitat was positive (Ng et al. 2004). Riley et al. (2006) contend that, to counteract genetic isolation, corridors across freeways could conceivably include more natural habitat so that home ranges could extend across freeways and rates of genetic exchange might be increased. Several studies have also indicated that fencing plays a significant factor in determining success. Although some species may use underpass or overpass systems without fences, some form of fencing does appear to be necessary for most species (Jackson and Griffin 2000). Ungulates commonly seek to


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avoid underpasses and will generally use them only if other access across the highway is barred (Ward 1982).

While the debate about the efficacy of wildlife crossings continues, at least three concepts are clear: (1) Protecting suitable habitat in the vicinity of crossing points is especially important; (2) consideration must be given to passage dimensions (Ng et al. 2004); and (3) if fence and passage systems are not designed for use by a broad range of wildlife, a project that facilitates passage for one species might constitute an absolute barrier for another (Jackson and Griffin 2000).

2.0 PROJECT SETTING

The wildlife movement Study Area (Study Area) for the College and Cannon High School Project is located in Carlsbad, California (Figure 1). The site is located within the San Luis Rey U.S. Geological Survey 7.5 minute quadrangle, Township 12 South, Range 4 West Section 3 (Figure 2). The proposed high school is located at the intersection of College Boulevard and Cannon Road; 33° 9'19.98"N, 117°17'11.27"W. The Study Area includes: the proposed high school location, Calavera Conservation Area to the north and east of the proposed high school location, Conservation Areas (specifically the intersection of El Camino Real and Cannon and to the north and south of Carlsbad Village Drive), and the surrounding roads (Cannon Road, College Boulevard, Carlsbad Village Drive, Tamarack, El Camino Real, Glasgow Drive and Harwich Drive) (Figure 3). These areas supported active trails that were used by the general public and were not marked with “No Trespassing” signage. The majority of the Study Area falls within the Conservation Areas.

3.0 METHODS AND SURVEY CONDITIONS

3.1 Literature Review

Prior to conducting the wildlife movement study, previous reports regarding wildlife movement and road-kills within and adjacent to the Study Area were reviewed. The literature reviewed included:

(a) Road-kill Potential on El Camino Real, along Robertson Ranch Southern Boundary (Merkel & Associates, Inc. 2007)

The report by Merkel & Associates, Inc. (2007) documents the results of a one-day site visit to assess potential wildlife movement within the area northwest of the Cannon Road and El Camino Real intersection. During the construction of Robertson Ranch, Preserve Calavera raised concerns that construction could potentially be increasing road-kill in the area. The site visit determined that the likely cause of road-kill in the area is due to lack of fencing along the


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northern side of El Camino Real. This report concluded that wildlife traveling from the Agua Hedionda Creek corridor, via box culverts under Cannon Road, and across the undeveloped area to El Camino Real are trying to get to the Agua Hedionda corridor located on the other side of the road. Wildlife crossing the road encounter a chain link fence and therefore must cross back over the road or attempt to go around. Although there is a culvert under El Camino Real that leads to the Agua Hedionda corridor, there is no method of funneling the wildlife through the corridor. The report also concluded that the potential increases of road-kill in the area are seasonal and not related to the construction of Robertson Ranch. The report recommends installing a fence along the northern side of El Camino Real.

(b) Report on Road-kill at El Camino Real and Cannon Road (Preserve Calavera 2007)

Preserve Calavera disputed the idea in the Merkel & Associates report (2007) that wildlife were using the box culverts under Cannon Road to travel from the Agua Hedionda Creek corridor to the undeveloped area at the intersection of Cannon Road and El Camino Real (Preserve Calavera 2007). In their assessment of wildlife movement, they concur that installing a fence along the northern side of El Camino Real would keep wildlife off the road and facilitate movement through the existing culvert.

(c) Final New High School at Cannon and College Environmental Impact Report (Carlsbad Unified School District 2008)

In December 2008, the Carlsbad Unified School District submitted a Final Environmental Impact Report (FEIR) for the New High School Project (Carlsbad Unified School District 2008). In this FEIR, the school district addresses comments on the Draft Environmental Impact Report (DEIR) from various entities. Several comments in the DEIR concerning the wildlife movement within and surrounding the proposed school site prompted the school district to further examine the topic in the FEIR. In reference to potential project impacts along Agua Hedionda Creek and Calavera Creek, the report concludes that the proposed project will not result in significant impacts to these wildlife corridors.

(d) Comments on FEIR Carlsbad High School and Wildlife Movement Corridor (Preserve Calavera 2009)

Preserve Calavera responded to the FEIR and disputed the School District’s claims that the area surrounding the proposed project is not a significant wildlife movement corridor (Preserve Calavera 2009). In this response, Preserve Calavera references the City of Carlsbad Habitat Management Plan (HMP) and the Robertson Ranch EIR, both of which identify the area in


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question as a significant wildlife corridor. The response identifies areas where they believe the FEIR is lacking: failure to identify wildlife undercrossing of College Boulevard; failure to identify existing conditions resulting in high rate of road-kill in the project area; and failure to comply with HMP conditions. Preserve Calavera requested that the following actions be taken: conduct a wildlife corridor study and assess existing and future impacts; install speed bumps and wildlife crossing signage; and add all of the edge effect mitigation measures from the Multiple Habitat Conservation Program (MHCP) and HMP.

3.2 Field Reconnaissance

Wildlife movement data was collected through a combination of sampling techniques: track surveys, remotely triggered camera surveys, and road-kill surveys. Each technique provided a unique way to obtain data on the distribution of mammal, and to a lesser degree, avian species within the Study Area and to document movement through the proposed high school location and surrounding areas. Incidental occurrences of special-status wildlife observed within the Study Area were also recorded.

In addition to the studies outlined below, wildlife biologist Brock Ortega performed a reconnaissance-level survey of the vicinity to note potential constraints and opportunities related to wildlife movement in the area.

3.2.1 Road-kill Survey

Road-kill surveys took place primarily along College Boulevard, Carlsbad Village Drive, Tamarack Avenue, El Camino Real, and Cannon Road at appropriate road segments within the Study Area (Figure 4). Each road within the Study Area was divided into one-tenth-mile segments to provide for more accurate mapping. All segments were surveyed on a daily basis before peak traffic periods (i.e., before 0830 hours on weekdays) for a period of 2.5 weeks (19 days). Road-kill surveys did not take place January 20–22 due to heavy rain. When road-kill was encountered, the following data was collected: road segment, species, apparent direction of travel, estimated age of kill, and age class of species. Surveys were conducted by driving the alignment at speeds no more than 25 mph and slower where safely feasible, while searching for any road-kill. Once road-kill was detected and location was marked on the map and the biologist filled out a data sheet once they were able to safely pull over.

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FIGURE 4

Road Kill Survey Area


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3.2.2 Track Survey

Two methods were used to conduct the track surveys; set scent stations and pedestrian trail surveys. Nine scent stations were set-up throughout the Study Area adjacent to drainages or other constraining areas that lead to or away from potential crossing locations or pinch-points in the landscape (Figure 5). Stations were set on dirt roads, paths, or adjacent bare dirt areas. Each station consisted of a one-meter circular plot of finely sifted gypsum and a rock, placed in the middle of the station that was baited with an artificial scent lure (Gusto) and a can of cat food. Wildlife traveling within the vicinity of the scent station were lured to the station by the artificial scent and bait placed on a rock. As an animal walked up to the scented rock, their tracks were captured in the gypsum surrounding the rock. The tracks were then identified to species and, if possible, direction of travel was determined. Each station was mapped using Global Positioning System (GPS). Scent stations were set-up and checked three times during the study. Rain throughout the week of January 18 reduced the number of scent station visitations.

Trails throughout the non-developed portions of the Study Area, including the Calavera Conservation Area, were walked to locate mammal tracks, direction of travel and scat (Figures 6 and 7). The small portion of the CNLM Conservation Area located at the intersection of El Camino Real and Cannon Road were included in the tracking survey because previous studies had indicated that coyotes travel through this area and there have been records of coyote road-kills at this intersection (Preserve Calavera 2009). All locations were mapped using GPS.

3.2.3 Camera Study

Five remotely triggered cameras were distributed throughout the Study Area in drainages or other constraining areas that lead to or away from potential crossings (Figure 8). Scent lures were placed opposite of the camera to attract wildlife moving through the area to the camera location. This was not anticipated to bias the results of the study by artificially drawing species in—this simply attracted proximate animals long enough to ensure that a good photo was taken of them. Cameras were left in place for 3 weeks (21 days) and were checked once a week to ensure they were functioning properly, replace batteries, and download images. Each pass of an animal through the field of the infrared heat sensor or motion sensor triggered the camera. Date and time of the pass were recorded on each photo. Camera locations were mapped using GPS. During the


6552-01 20 April 2010

second week of the study, cameras 3 and 5 were stolen. For one of the cameras (3), the perpetrator left the memory card so those images were able to be downloaded.

3.3 Survey Limitations

The wildlife movement study was conducted during the winter months when most wildlife is less active and only for a very brief period of time. It is best to conduct these types of studies over a cross section of seasons throughout a year because some species are much more detectable during the period when they are rearing young (spring/summer) or when young are leaving their parents home range to establish home ranges of their own (fall). Some smaller and medium sized species become more active and less secretive when raising young (e.g., gray fox). Other species with larger home ranges are more likely to be “captured” when the study takes place over a longer time period.

Reptile detections would have been greatly reduced by the cooler temperatures during the study period. Documentation of avian movement is difficult to obtain through the methods used here. For those types of studies, radio or GPS tags, or banding is the best method. These methods were biased toward detection of mammalian movement through the landscape.

1

2

3

4

5

6

7

8

9

FIGURE 5

Track Surveys - Scent Station Locations


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Scent Station Locations

SOURCE: DigitalGlobe, 2008


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CARLS BAD VILLAGE DR

CANNON RD

E L CAMINO REAL

CO

LLEGE

BLTAMAR A C K

AV

FIGURE 6

Track Survey - Trail Overview and Species Locations


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Special Status Species Survey Locations

California gnatcatcher

Northern harrier

White-tailed kite

red-tailed hawk

Coyote scat

Coyote Track

Survey Route

Inset Area

See Figure 7for Inset Area


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EL CAMINO REAL

CA

NN

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3-45

6

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FIGURE 7

CNLM Conservation Area


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Cameras (#)

Coyote scat

Coyote Track

Opossum Track

Raccoon Track

Scent Station (#)

Wildlife Areas

SOURCE: SanGIS 2008; DigitalGlobe 2008


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EL CAMINO REAL

CARLSBAD VILL AGE DR

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FIGURE 8

Camera Locations


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4.0 RESULTS OF SURVEYS

4.1 Road-Kill Survey

Over the course of 3 weeks, three road-kill incidents were observed; two along El Camino Real and one along College Boulevard (Table 2, Figure 4). The first road-kill incident appears to have occurred prior to the initiation of the wildlife corridor study. The rabbit (Sylvilagus bachmani) found along El Camino Real at segment ECR5 was observed on the first day of the study and had already begun decomposing. A second rabbit was observed on College Boulevard at segment CB9. The good condition of the animal, and lack of observation during the previous day’s survey, indicated that the incident had occurred within the last 24-hour period. The third road-kill incident, an immature red-shouldered hawk (Buteo lineatus), was observed along El Camino Real at segment ECR18. This hawk was found on the shoulder of the north side of El Camino Real and may have been traveling northeast. No other road-kill incidents were observed during the surveys. The speed limit along College Boulevard is 45 mph and the speed limit for El Camino Real is 55 mph.

Table 2 Road-kill Survey Results

Date Time Conditions Results

1/11/10 6:45–8 a.m. Clear, 55F, 0 mph winds ECR5: very old rabbit on north side of road

1/12/10 6:15–7:15 a.m. Foggy, 60F, 0 mph winds ECR5: very old rabbit on north side of road

1/13/10 6:15–7:15 a.m. Foggy, drizzle, 60F, 0 mph winds ECR5: very old rabbit on north side of road

1/14/10 6:30–7:30 a.m. Sunny, 60F, 0 mph winds n/a


1/16/10 8–9 a.m. Sunny, 65F, 0 mph winds n/a

1/17/10 8–9 a.m. Sunny, 65F, 0 mph winds n/a

1/18/10 6:30–7:30 a.m. Overcast, rain, 58F CB9: rabbit on west side of road traveling east

1/19/10 6:15–7:30 a.m. Overcast, rain, 58F n/a

1/20/10 n/a n/a Raining, no survey 1/21/10 n/a n/a Raining, no survey 1/22/10 n/a n/a Raining, no survey 1/23/10 9–10 a.m. Overcast, 60F n/a

1/24/10 9–10 a.m. Sunny and clear, 60F n/a

1/25/10 7:30–8:30 a.m. Sunny and clear, 55F, 0 mph winds n/a


1/27/10 6:30–7:45 a.m. Sunny, 55F, 0 mph winds ECR18: Red-shouldered hawk, immature, on shoulder of north side of road, potentially

traveling northeast 1/28/10 6:30–7:30 a.m. Sunny, 55F, 0 mph winds ECR18: Red-shouldered hawk

1/29/10 6:30–7:30 a.m. Sunny, 55F, 0 mph winds ECR18: Red-shouldered hawk


6552-01 30 April 2010

4.2 Track Surveys

4.2.1 Scent Station Surveys

Six wildlife species tracks were observed within the scent stations: coyote (Canis latrans), raccoon (Procyon lotor), domestic dog (Canis lupus familiaris), ground squirrel (Spermophilus beecheyi), crow (Corvus brachyrhynchos), and brush rabbit. Table 3 summarizes the results of the scent station survey.

Table 3 Scent Station Survey Results

SESSION 1 – 1/14/10 Station Species Direction of travel

1 Raccoon West (W) Coyote Unknown

2 Raccoon Northwest (NW)

3 Coyote Scat 4 Domestic dog n/a 5 Domestic dog n/a 6 Coyote Unknown


Table 3 (Continued)

6552-01 31 April 2010


Raccoon East (E) Ground squirrel Unknown 1

Coyote E 2 No tracks or scat n/a 3 Domestic dog n/a 4 Domestic dog n/a

Coyote W 5

Coyote South (S) 6 Coyote W 7 No tracks or scat n/a

Crow Unknown 8

Ground squirrel Unknown 9 Rabbit North (N) and S


Coyote E 1

Coyote Southwest (SW) 2 Raccoon Unknown 3 No tracks or scat n/a 4 Domestic dog n/a 5 Domestic dog n/a 6 No tracks could be identified n/a

Coyote S 7

Ground squirrel SW Coyote N

8 Ground squirrel N

9 Coyote Unknown

4.2.2 Trail Surveys

Trail surveys focused on the non-developed areas within and adjacent to the proposed high school site. The areas surveyed include: Calavera Conservation Area and CNLM conservation areas located north of the intersection of El Camino Real and Cannon Road, and a section north of Carlsbad Village Drive near scent station 7 (Figures 6 and 7).


6552-01 32 April 2010

Calavera Conservation Area

The majority of trails within the park and adjacent Calavera Conservation Area are compacted and heavily influenced by human activity. Several dogs were observed unleashed and running freely within the open space. Recreational bicycling throughout this area occurs with frequency and many of the secondary trails off of the main trails are often used by bikes. All of these trails are potentially used by wildlife. Human and domestic dog influences within this area limited the ability to detect wildlife tracks as much of the area was disturbed by frequent foot and bicycle traffic. Only one set of coyote tracks was observed at the eastern side of the park. From the orientation of the tracks, it appears that the coyote was traveling south along a trail. Coyote scat was detected at four locations within this area (Figure 6).

CNLM Conservation Area: El Camino Real / Cannon Road

The small portion of the Conservation Area at the intersection of El Camino Real and Cannon Road was also surveyed for mammal signs (tracks and scat) (Figure 7). The topography of this area appears to have been modified in the recent past. There are several sets of sprinklers within the open space which indicate that the area is being restored. Very little native vegetation occurs within this area, and total vegetation cover is less than 10%. Several coyote tracks were observed within the open space at the intersection of El Camino Real and Cannon Road. As shown in Figure 7, the abundance of tracks indicates that coyotes frequent this area and use it to travel from one open space to another. Other tracks observed within this area included, raccoon, opossum (Didelphis virginiana), rabbit, and domestic dog.

Carlsbad Village Drive Conservation Area

The third area surveyed is located near scent station 7 to the north and south of Carlsbad Village Drive (Figure 6). The open space to the south of Carlsbad Village Drive is surrounded by a metal welded bar fence and the only access is through a locked gate and marked with “No Trespassing” signage; therefore, this area was not surveyed. This portion of the Study Area is not a part of the Conservation Area managed by CNLM. Half of the area located to the north of Carlsbad Village Drive is used as a dog park and the other half consists of dense riparian habitat leading to chaparral. The two sides of Carlsbad Village Drive may be connected by a culvert, but one could not be located during the survey. The northern area is heavily influenced by humans and domestic dogs, thus making tracking difficult. No scat or tracks were observed within the park. To assist in determining if wildlife used this area, a scent station (7) was set-up within the northern open space, away from the designated trails. The results of the scent station tracking can be found in Table 3.


6552-01 33 April 2010

4.3 Camera Study

Five remotely triggered cameras were distributed throughout the Study Area in drainages or other constraining areas that lead to or away from potential wildlife movement areas (Figure 8). Two wildlife species were detected within the vicinity of the camera locations: coyote and rabbit. Abundant human and domestic dog use was also documented. A summary of wildlife-related picture, date, and time along with species and direction of travel is summarized in Table 4 and example photos are included on Figure 9a and 9b. Based on coloration differences in their tails, it appears that there were at least three individual coyotes documented during this study and that one (identified by the white tail tip) was photographed by cameras 1 and 5, documenting that they do move from the 400-foot-wide strip near College Boulevard and Carlsbad Village Drive to, and through, the 100-foot-wide strip south of Cannon Road.

Table 4 Camera Survey Results

Camera Date Time Species Direction of Travel 1/23/10 10:44 p.m. Coyotes (2) Northwest (NW)

1 1/27/10 6:07 p.m. Coyote NW

2 1/29/10 4:23 a.m. Rabbit unknown 3 n/a n/a No wildlife photos n/a 4 n/a n/a No wildlife photos n/a

1/11/10 12:29 p.m. Coyote Southwest (SW) 1/15/10 2:07 a.m. Coyote SW 1/15/10 2:08 a.m. Same coyote as above, came back

to smell lure SW

1/15/10 2:10 a.m. Same coyote as above SW 1/15/10–1/27/10 various Rabbits SW, Northeast (NE),

West (W) 1/26/10 4:37 a.m. Coyote NE

5

1/28/10 4:09 a.m. Coyote NE

4.4 Special-status Biological Resources

Special-status species anecdotally detected during this study are described below.

4.4.1 Special-status Wildlife

During the surveys, all wildlife observed within the Study Area were recorded. A complete list of wildlife can be found in Appendix A. Three special-status bird species were observed within the Study Area: northern harrier (Circus cyaneus; a California Department of Fish and Game


6552-01 34 April 2010

[CDFG] Species of Concern), white-tailed kite (Elanus leucurus; a CDFG Protected Species), and the federally listed threatened coastal California gnatcatcher (Polioptila californica californica). In addition, a red-tailed hawk nest was observed within the sycamore trees in the Conservation Area. The locations of these species can be found on Figure 8.

4.4.2 Wildlife Corridors and Habitat Linkages

CNLM Conservation Area: El Camino Real / Cannon Road

There are four potential crossings within this portion of the Conservation Area that can be utilized by wildlife to access surrounding open spaces. A set of three box culverts, which run under Cannon Road approximately 70 feet north of the intersection with El Camino Real, connect this area to the trail behind a large concrete wall. The concrete wall runs parallel to Cannon Road and ends where Cannon Road intersects with College Boulevard. There is an additional wall that separates the trail from Agua Hedionda Creek. Another large culvert, under El Camino Real, connects this area to the riparian habitat south of El Camino Real. A large pool of standing water is located at the northern entrance of this culvert. Just to the west of culvert there is a trail that heads from the area upslope, to either the road, or agricultural fields northwest of El Camino Real. There is also a paved access road, adjacent to the trail, from El Camino Real to the area which may funnel wildlife to and from the area. An additional paved access road coming from the Robertson Ranch development south to the open space, may also funnel wildlife from the open space to and from Cannon Road. Based on coyote track locations and directions within the open space, it appears that coyotes are traveling from the Robertson Ranch paved road and the box culverts located under Cannon along the northern edge of the open space, south to the trail and up to either El Camino Real or the agricultural fields. This potential movement is shown in Figure 10.


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1

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FIGURE 10

Wildlife Movement and Barriers


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Potential Wildlife Movement Routes

Concrete Culvert (1 and 2)

Barrier Type

3-strand wire fence

4’ chain link fence

4-stand wire fence

5’ chain link fence

5’ metal bar fence

6’+ block wall

split rail/3-strand wire fence

Steep Slopes


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5.0 DISCUSSION

Based on the literature review and conservation planning efforts, it is apparent that in general, there is concurrence that wildlife move through the Study Area. In addition to the literature and data provided here, noting use by coyotes, the CNLM biologist has observed mule deer use near College Boulevard, west of the High School site. This study provided very little data, other than road-killed rabbit at two locations and a few coyote detections; however, this is not unexpected given the brief timeframe and seasonal constraints of the study. We do know that urban-adapted top-level predators (coyotes) and herbivores (mule deer) use the large block of non-developed land that occupies the area anchored by the Calavera Hills & Robertson Ranch Habitat Conservation Area and includes the proposed High School site, proposed Cannon Road extension, and other private parcels. Since there are relatively few physical constraints to movement in this area, they are free to move throughout the landscape of this block, constrained only by resources and conspecific territories. For nearly all potentially occurring medium and large mammals (i.e., grey fox, bobcat, coyote, mule deer), the block provides enough area to form complete home ranges for individuals. When medium and large wildlife move into or out of this block and other large blocks in the region (e.g., lagoons, Camp Pendleton, Lake Hodges areas), they must pass through a variety of smaller and constrained areas as highlighted in Figures 10 and 11. A discussion of each reach of potential connection areas is in Table 5.

Table 5 Potential Wildlife Connections Within the Study Area

Figure 11 Identifier

Minimum Width1 Length2 Comments3

A 158 1,733 There are no barriers to movement through this area. A 3-strand wire fence separates the habitat from adjacent roads. Other fencing separates the habitat from adjacent homes. Provides connections to northern open space.

B 793 2,269 There are no barriers to movement through this area. A split-rail and 3-strand wire fence separate the habitat from the adjacent road. Provides connections to northern open space.

C 236 1,510 There are no physical barriers, though there is a steep slope in the middle which might restrict wildlife use to a degree. Provides a connection between Areas A and B.

D 403 2,988 There is an approximately 5-foot-tall metal bar fence with approximate 5-inch gaps between the bars. There are also numerous gaps below the fence that would allow coyotes and smaller wildlife through, but would prohibit mule deer from crossing through. It is unlikely that mule deer would get through this area without difficulty. It is likely that any that made it to this area would backtrack to the north. This Area leads to Area J, which is constrained by 5-foot-tall chain link fencing with apparently few gaps. Wildlife using this would also need to cross Carlsbad Village Drive.


Table 5 (Continued)

6552-01 42 April 2010



E 236 1,381 This narrow connection has no barriers until it reaches Area J, where a 5-foot tall chain link fence occurs effectively blocking the route. Additionally, wildlife using Area E would need to cross Tamarack Avenue.

F 162 1,287 There are no movement constraints other than slightly steeper slopes. Wildlife moving here would need to cross College Boulevard.

G 445 3,259 There are no barriers to movement other than 3-strand wire fences. These should pose no constraint to any of the species which might use this area. Wildlife using this Area would need to cross College Boulevard and Glasgow Drive. This serves as the main connection between the Conservation Area and open space to the north. It has been shown to convey coyote.

H 422 1,405 There are no barriers to movement other than a 4-strand wire fence. Wildlife using this Area would need to either cross over College Boulevard or use Culvert 1. It is unlikely that species would use Culvert 1 unless they are directed there by directional fencing. Species now probably cross at grade. Directional fencing between Area H and Area I would help avoid road-kill in this area.

I 141 3,746 This area has been shown to be used by coyotes and likely is capable of conveying bobcat as well. In its current state, it is constraining to wildlife movement along its length and at the intersection of Cannon Road and El Camino Real, but they do use it. There are opportunities to enhance its effectiveness by (1) filling the gap in the wall between Cannon Road and the Area at Windfall Way, (2) removing the block wall between the north fork of Agua Hedionda Creek and the open areas south of the Cannon Road block wall, thereby making a wider habitat swath usable to wildlife and freeing movement along the creek, and (3) ensuring that wildlife can make it under the El Camino Real underpass without needing to swim.

J 679 1,663 This area is currently constrained by the 5-foot-tall chain link fence. It appears that there are few gaps in this fence that could allow wildlife to cross through. There is an opportunity to enhance the overall connectivity between the lagoons by opening up this fence at strategic locations, or adopting a more wildlife friendly fence design (e.g., 3-strand wire or split rail). However, wildlife would still need to cross Tamarack Avenue.

K 92 2,445 Area K runs along the south fork of Agua Hedionda Creek through a mobile home park. At the time of the review there were numerous migratory ducks present in the creek. The area appears to be surprisingly buffered from the adjacent development and probably supports movement of coyote. There are no direct barriers to movement.

L 303 1,686 An approximate 4-foot tall chain link fence occurs along El Camino Real and this probably forms a formidable barrier to most wildlife. There are occasional gaps or breaks in the fence, but until wildlife locate the gaps, they are at increased risk of being hit by cars. An


Table 5 (Continued)

6552-01 43 April 2010



opportunity to increase movement would to either replace the chain link with 3-strand wire fencing (but this might increase road kill), or provide an undercrossing culvert at this location and install direction fencing to it on the north side of El Camino Real. As indicated earlier, there is a significant amount of coyote activity concentrated at the northwestern corner of El Camino Real and Cannon Road.

M 512 3,693 Wildlife using this area might be constrained by 4-foot-tall chain link fencing along Cannon Road. Additionally, wildlife would need to cross Frost Avenue to get through Area N. Replacing the chain link fencing with 3-strand wire fencing, would help but this might increase road-kill and given the configuration of Area M and N and reduced connection to the larger Conservation Area to the northeast, it is probably not advisable.

N 546 1,955 Area N has poor connectivity to Area O and the larger Conservation Area to the northeast, but does serve to connect Areas I and K to Area L by allowing wildlife to cross under Cannon Road. Opportunities to enhance wildlife movement would involve ensuring that wildlife do not need to swim to get under Cannon road.

O n/a n/a While on an aerial map it appears that there might be connection opportunities in this area, there is a very steep slope, non-native vegetation, and proximate residences in the area that would likely preclude use by most wildlife. If they did make it across El Camino Real and through this area, then they have a short route to Area L and the lagoon.

1 Narrowest width in feet 2 Length of entire segment in feet 3 Refer to Figure 10 for barrier type representation

Despite the limited data gathered through this study, the documented movement of coyote through the constrained linkage “I” to larger blocks of habitat to the north, indicates that this area is one of the key movement areas for wildlife in the vicinity to get to/from more coastal habitat blocks to other lands to the east or north. Constrained linkages “F” and “H” would also be important.

With the proposed high school site, wildlife movement may be further constrained through the area and may be blocked entirely with the development of the planned roadway extension if considerations are not made to facilitate wildlife movement. Recommendations are provided below to facilitate or improve wildlife movement through the Study Area given existing and potential future constraints. The locations of these recommendations are depicted on Figure 12.

1. Remove bar fence along Carlsbad Village Drive (Area D) and replace with 3-strand wire fencing or provide gaps for mule deer-sized wildlife to pass through


6552-01 44 April 2010

2. Remove the chain link fencing along Tamarack Avenue (Areas E and J) and replace with 3-strand wire fencing, or provide gaps for large wildlife to pass through

3. Install directional fencing, i.e., 5-foot-tall chain link fencing, along the east side of Cannon Road between the culvert and the metal bar fencing to the north and south to crossing Area I to the south so that wildlife are forced to use the culvert instead of making risky at-grade crossings over Cannon Road

4. To improve the functionality of Area I, it is recommended that the block wall along Cannon Road, be extended to fill the gap at Wind Trail Way and that the block wall between the open area south of Cannon Road and the north fork of Agua Hedionda Creek be removed so that wildlife are not forced to choose between a sparsely vegetated route or a rip-rapped, flooded route, but instead have the entire complement to use while moving between Agua Hedionda Lagoon and open space to the north

5. Replace the chain link fencing along El Camino Real (west of Cannon Road) and Cannon Road (south of El Camino Real) with post and rail, 3-strand wire, or other open fencing option to better allow wildlife to cross into habitat, OR a better option would be to install a culvert under El Camino Real (west of Cannon Road) to provide better and safer access for wildlife to Area L. If the latter option is chosen, then directional fencing on either side of El Camino Real would be necessary

6. Ensure that wildlife have dry-ground options when trying to cross under the bridges at El Camino Real and Cannon Road. These are situated where Agua Hedionda Creek connects to Agua Hedionda Lagoon and appear to be constrained by inundation

7. When constructing the new proposed high school, it will be necessary to ensure that wildlife can still move around the school after hours to get to and through the Agua Hedionda Creek system. Although chain link fencing or walls may be preferred to prevent human access into adjacent open space areas around the school, these fence/wall types are not permeable for wildlife and are not recommended. Permeable fencing (i.e., post and rail, 3-strand wire, or other open fencing) is considered sufficient to prevent convenient human access and set boundaries while continuing to allow wildlife movement, and this fencing type is recommended in areas of the school site abutting open space areas.

8. Construction of the Cannon Road extension should include appropriately sized culverts (i.e., suitable for use by mule deer) with directional fencing to allow wildlife to move through the open-space landscape

In addition to these specific recommendations, several road crossing areas with no existing undercrossings were identified in this study. For this study area and the type and density of wildlife species moving through the area, signage, lighting, speed bumps, or other traffic control


6552-01 45 April 2010

measures would either not be considered highly effective and/or would not be practical. The school district may consider implementing a driver education program for parents and student drivers to make them more aware of potential wildlife crossing areas.

In conclusion, though this study was conducted for a brief period of time and during the least optimal season, it is apparent that larger wildlife use the area and likely move through the larger blocks of habitat to other open space to the north and southwest. Installation of the proposed school and road extensions will need to be carefully designed in order to not further impede wildlife movement through the area. A number of recommendations were made which might enhance wildlife movement through the area. Some of these may not be practical depending on property ownership, easements, fencing restrictions, etc., but these form a basis by which to begin discussion with appropriate parties.


6552-01 46 April 2010


L NO

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FIGURE 11

Linkage Constraint Levels


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See Table 5 in Report

Constraints

Large habitat block

Low linkage constraint level

Medium linkage constraint level

High linkage constraint level

X


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FIGURE 12

Recommendations for Wildlife Movement Facilitation and Improvements


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Drainage Improvements

Fence Modification

Fence Installation

Wall Removal

Site Recommendations


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6.0 LITERATURE CITED

Aars, J., and R.A. Ims. 1999. "The Effect of Habitat Corridors on Rates of Transfer and Interbreeding between Vole Demes." Ecology 80:1648–1655.

Beier, P., and S. Loe. 1992. "A Checklist for Evaluating Impacts to Wildlife Movement Corridors." Wildlife Society Bulletin 20:434–440.

Bennett, A.F. 2003. Linkages in the Landscape: The Role of Corridors and Connectivity in Wildlife Conservation. World Conservation Union.

Bolger D.T., T.A. Scott, and J.T. Rotenberry. 1997. "Breeding Bird Abundance in an Urbanized Landscape in Coastal Southern California." Conservation Biology 11:406–421.

Brinkerhoff, R.J., N.M. Haddad, and J.L. Orrock. 2005. "Corridors and Olfactory Predator Cues Affect Small Mammal Behavior." Journal of Mammalogy 86:662–669.

Carlsbad Unified School District. 2008. Final New High School at Cannon and College Environmental Impact Report. Prepared by The Planning Center. December 2008.

Carr, T., R. Dacanay, K. Drake, C. Everson, A. Sperry, and K. Sullivan. 2003. Wildlife Crossings: Rethinking Road Design to Improve Safety and Reconnect Habitat. Portland State University Planning Workshop.

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APPENDIX A List of Wildlife Observed

Within Study Area

APPENDIX A List of Wildlife Observed Within Study Area

6552-01 A-1 April 2010

WILDLIFE SPECIES – VERTEBRATES BIRDS

ACCIPITRIDAE – HAWKS Accipiter cooperii – Cooper's hawk Buteo jamaicensis – red-tailed hawk Buteo lineatus – red-shouldered hawk Circus cyaneus – northern harrier Elanus leucurus – white-tailed kite

AEGITHALIDAE – BUSHTITS Psaltriparus minimus – bushtit

COLUMBIDAE – PIGEONS AND DOVES Zenaida macroura – mourning dove

CORVIDAE – JAYS AND CROWS Aphelocoma californica – western scrub-jay Corvus brachyrhynchos – American crow

CHARADRIIDAE – PLOVERS Charadrius vociferus – killdeer

CUCULIDAE – CUCKOOS AND ROADRUNNERS Geococcyx californianus – greater roadrunner

EMBERIZIDAE – `BUNTINGS AND SPARROWS Pipilo crissalis – California towhee Passerculus sandwichensis – Savannah sparrow Zonotrichia leucophrys – white-crowned sparrow

FALCONIDAE – FALCONS Falco sparverius – American kestrel

FRINGILLIDAE – FINCHES Carpodacus mexicanus – house finch

APPENDIX A (Continued)

6552-01 A-2 April 2010

ICTERIDAE – BLACKBIRDS AND ORIOLES Agelaius phoeniceus – red-winged blackbird Molothrus ater – brown-headed cowbird Sturnella neglecta – western meadowlark

LARIDAE – GULLS AND TERNS Larus californicus – California gull

MIMIDAE – THRASHERS Toxostoma redivivum – California thrasher

PARULIDAE – WOOD WARBLERS Geothlypis trichas – common yellowthroat

SCOLOPACIDAE – SANDPIPERS Tringa semipalmata – willet

SYLVIIDAE – GNATCATCHERS Polioptila californica – California gnatcatcher

TIMALIIDAE – LAUGHING THRUSH AND WRENTIT Chamaea fasciata – wrentit

TROCHILIDAE – `HUMMINGBIRDS Calypte anna – Anna's hummingbird

TYRANNIDAE – TYRANT FLYCATCHERS Sayornis nigricans – black phoebe Sayornis saya – Say's phoebe Tyrannus verticalis – western kingbird

TROGLODYTIDAE – WRENS Cistothorus palustris – marsh wren Thryomanes bewickii – Bewick's wren

MAMMALS

CANIDAE – WOLVES AND FOXES * Canis lupus familiaris – domestic dog Canis latrans – coyote


6552-01 A-3 April 2010

DIDELPHIDAE – NEW WORLD OPOSSUMS * Didelphis virginiana – Virginia opossum

LEPORIDAE – HARES AND RABBITS Sylvilagus bachmani – brush rabbit

PROCYONIDAE – RACCOONS AND RELATIVES Procyon – - common raccoon

SCIURIDAE – SQUIRRELS Spermophilus beecheyi – California ground squirrel

* signifies introduced (non-native) species


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Documents

CarlsbadHSCorridorReport Final April 2010 · College and Cannon Carlsbad High School Site Wildlife Movement Study 6552-01 1 April 2010 1.0 INTRODUCTION The Carlsbad Unified School