Daily Rules, Proposed Rules, and Notices of the Federal Government
The coordinates or plot points or both from which the maps for this critical habitat designation were generated are included in the administrative record and are available on our Internet site (
The critical habitat areas we are designating in this rule constitute our current best assessment of the areas that meet the definition of critical habitat for Riverside fairy shrimp. We are designating:
• Approximately 466 acres (ac) (189 hectares (ha)), in 2 subunits, as critical habitat in Ventura County.
• Approximately 396 ac (160 ha), in 4 subunits, as critical habitat in Orange County.
• Approximately 862 ac (348 ha), in 7 subunits, as critical habitat in San Diego County.
In total, we are designating approximately 1,724 ac (698 ha) as critical habitat for this species. We are also:
• Exempting 1,988 ac (804 ha) from critical habitat designation in Orange County and San Diego County.
• Excluding 1,259 ac (510 ha) from critical habitat designation in Orange County, Riverside County, and San Diego County.
It is our intent to discuss in this final rule only those topics directly relevant to the revision of critical habitat for the Riverside fairy shrimp under the Act (16 U.S.C. 1531
The Riverside fairy shrimp was listed as an endangered species on August 3, 1993 (58 FR 41384). For a history of Federal actions prior to 2001, please refer to the September 21, 2000, proposed critical habitat rule (65 FR 57136). On May 30, 2001, we published a final rule designating critical habitat for the Riverside fairy shrimp (66 FR 29384). On November 6, 2001, the Building Industry Legal Defense Foundation, Foothill/Eastern Transportation Corridor Agency, National Association of Home Builders, California Building Industry Association, and Building Industry Association of San Diego County filed a lawsuit in the U.S. District Court for the District of Columbia challenging the
On April 27, 2004, we again proposed to designate critical habitat for the Riverside fairy shrimp (69 FR 23024). The final critical habitat rule was published in the
(1) We added updated information on the general impacts of climate change and its potential impacts to Riverside fairy shrimp in the
(2) We added a discussion to the
Regardless of the occupancy status (documented or presumed; pre- or post-listing) of each unit, in Table 1 of the March 1, 2012, publication (77 FR 12543), we provided our justification for determining why these areas are essential for the conservation of the species under section 3(5)(A)(ii) of the Act. For those units for which we lack data confirming occupancy at the time of listing, we are alternatively designating them under section 3(5)(A)(ii) because they are essential for the conservation of Riverside fairy shrimp and a designation limited to areas confirmed to be occupied at the time of listing would be inadequate to ensure the conservation of the species. We provide further explanation of our method and rationale for defining critical habitat boundaries in the
(3) Based on a public comment, we updated the name of the vernal pool complex at Marine Corps Air Station (MCAS) Miramar from “AA 1-7, 9-13 East Miramar (Pool 10) (AA1 East)” to its recommended name “East Miramar (AA1 South + Group) (Pool 4786; previously Pool 12).”
(4) In the proposed revised critical habitat rule, Table 4 incorrectly identified 6 ac (3 ha) of land in Subunit 4c as State-owned. The land is actually owned by the North [San Diego] County Transit District. Table 3 in this final revised rule has been updated to show the correct land ownership.
(5) We are now excluding lands owned by the Department of Homeland Security (DHS) in Subunit 5b (29 ac (12 ha)) and a portion of the lands in Subunit 5h (11 ac (4 ha)) from this final critical habitat designation based on national security. This exclusion is consistent with the exclusion of DHS lands in our previous final critical habitat rule published April 12, 2005 (70 FR 19154), due to national security concerns related to the operation and maintenance of the Border Infrastructure System (BIS).
In our proposed revised critical habitat rule published June 1, 2011 (76 FR 31686), we sought comments on whether or not these Federal lands should be considered for exclusion under section 4(b)(2) of the Act for national security reasons, whether such exclusion is or is not appropriate, and whether the benefits of excluding any specific area outweigh the benefits of including that area as critical habitat and why. On October 16, 2012, DHS commented that designation of these lands could interfere with U.S. Customs and Border Patrol Protection activities along the border and urged exclusion of the lands for national security reasons. Based on the national security importance of DHS maintaining access to these border areas, the Secretary is exercising his discretion to exclude lands owned by DHS in this final critical habitat rule. Details on our rationale can be found in the “Exclusions Based on National Security Impacts” section below.
(6) In the June 1, 2011, proposed revised rule, we stated that we were considering excluding lands owned by or under the jurisdiction of the Orange County Central-Coastal Natural Community Conservation Plan/Habitat Conservation Plan (NCCP/HCP), the Orange County Southern Subregion HCP, the Western Riverside County MSHCP, City of Carlsbad Habitat Management Plan (HMP) under the San Diego Multiple Habitat Conservation Program (MHCP), and County of San Diego Subarea Plan under the MSCP. We have now made a final determination that the benefits of exclusion outweigh the benefits of inclusion of lands covered by these plans. Therefore, the Secretary is exercising his discretion to exclude approximately 89 ac (36 ha) covered by the Orange County Central-Coastal NCCP/HCP, 233 ac (94 ha) covered by the Orange County Southern Subregion
Critical habitat is defined in section 3 of the Act as:
(1) The specific areas within the geographical area occupied by the species, at the time it is listed in accordance with the Act, on which are found those physical or biological features
(a) Essential to the conservation of the species and
(b) Which may require special management considerations or protection; and
(2) Specific areas outside the geographical area occupied by the species at the time it is listed, upon a determination that such areas are essential for the conservation of the species.
Conservation, as defined under section 3 of the Act, means to use and the use of all methods and procedures that are necessary to bring an endangered or threatened species to the point at which the measures provided pursuant to the Act are no longer necessary. Such methods and procedures include, but are not limited to, all activities associated with scientific resources management such as research, census, law enforcement, habitat acquisition and maintenance, propagation, live trapping, and transplantation, and, in the extraordinary case where population pressures within a given ecosystem cannot be otherwise relieved, may include regulated taking.
Critical habitat receives protection under section 7 of the Act through the requirement that Federal agencies ensure, in consultation with the Service, that any action they authorize, fund, or carry out is not likely to result in the destruction or adverse modification of critical habitat. The designation of critical habitat does not affect land ownership or establish a refuge, wilderness, reserve, preserve, or other conservation area. Such designation does not allow the government or public to access private lands. Such designation does not require implementation of restoration, recovery, or enhancement measures by non-Federal landowners. Only where a landowner requests Federal agency funding or authorization for an action that may affect a listed species or critical habitat would the consultation requirements of section 7(a)(2) of the Act apply.
Under the first prong of the Act's definition of critical habitat, areas within the geographical area occupied by the species at the time it was listed are included in a critical habitat designation if they contain physical or biological features (1) which are essential to the conservation of the species and (2) which may require special management considerations or protection. For these areas, critical habitat designations identify, to the extent known using the best scientific and commercial data available, those physical or biological features that are essential to the conservation of the species (such as space, food, cover, and protected habitat). In identifying those physical or biological features within an area, we focus on the principal biological or physical constituent elements (primary constituent elements (PCEs) such as roost sites, nesting grounds, seasonal wetlands, water quality, tide, soil type) that are essential to the conservation of the species. PCEs are those specific elements of the physical or biological features that provide for a species' life-history processes and are essential to the conservation of the species.
Under the second prong of the Act's definition of critical habitat, we can designate critical habitat in areas outside the geographical area occupied by the species at the time it is listed, upon a determination that such areas are essential for the conservation of the species. For example, an area currently occupied by the species but that was not occupied at the time of listing may be essential to the conservation of the species and may be included in the critical habitat designation. We designate critical habitat in areas outside the geographical area occupied by a species only when a designation limited to its range would be inadequate to ensure the conservation of the species.
Section 4 of the Act requires that we designate critical habitat on the basis of the best scientific and commercial data available. Further, our Policy on Information Standards Under the Endangered Species Act (published in the
When we are determining which areas should be designated as critical habitat, our primary source of information is generally the information developed during the listing process for the species. Additional information sources may include the recovery plan for the species, articles in peer-reviewed journals, conservation plans developed by States and counties, scientific status surveys and studies, biological assessments, other unpublished materials, or experts' opinions or personal knowledge.
Habitat is dynamic, and species may move from one area to another over time. We recognize that critical habitat designated at a particular point in time may not include all of the habitat areas that we may later determine are necessary for the recovery of the species. For these reasons, a critical habitat designation does not signal that habitat outside the designated area is unimportant or may not be needed for recovery of the species. Areas that are important to the conservation of the species, both inside and outside the critical habitat designation, will continue to be subject to: (1) Conservation actions implemented under section 7(a)(1) of the Act, (2) regulatory protections afforded by the requirement in section 7(a)(2) of the Act for Federal agencies to ensure their actions are not likely to jeopardize the continued existence of any endangered or threatened species, and (3) the prohibitions of section 9 of the Act if actions occurring in these areas may affect the species. Federally funded or permitted projects affecting listed species outside their designated critical habitat areas may still result in jeopardy findings in some cases. These protections and conservation tools will continue to contribute to recovery of this species. Similarly, critical habitat designations made on the basis of the best available information at the time of designation will not control the direction and substance of future recovery plans, habitat conservation plans (HCPs), or other species conservation planning efforts if new information available at the time of these planning efforts calls for a different outcome.
Our analyses under the Act include consideration of ongoing and projected changes in climate. The terms “climate” and “climate change” are defined by the Intergovernmental Panel on Climate Change (IPCC). The term “climate” refers to the mean and variability of different types of weather conditions over time, with 30 years being a typical period for such measurements, although shorter or longer periods also may be used (IPCC 2007a, p. 78). The term “climate change” thus refers to a change in the mean or variability of one or more measures of climate (e.g., temperature or precipitation) that persists for an extended period, typically decades or longer, whether the change is due to natural variability, human activity, or both (IPCC 2007a, p. 78).
Scientific measurements spanning several decades demonstrate that changes in climate are occurring, and that the rate of change has been faster since the 1950s. Examples include warming of the global climate system, and substantial increases in precipitation in some regions of the world and decreases in other regions. (For these and other examples, see IPCC 2007a, p. 30; and Solomon
Scientists use a variety of climate models, which include consideration of natural processes and variability, as well as various scenarios of potential levels and timing of GHG emissions, to evaluate the causes of changes already observed and to project future changes in temperature and other climate conditions (for example, Meehl
Various changes in climate may have direct or indirect effects on species. These effects may be positive, neutral, or negative, and they may change over time, depending on the species and other relevant considerations, such as interactions of climate with other variables (for example, habitat fragmentation) (IPCC 2007b, pp. 8-14, 18-19). Identifying likely effects often involves aspects of climate change vulnerability analysis. Vulnerability refers to the degree to which a species (or system) is susceptible to, and unable to cope with, adverse effects of climate change, including climate variability and extremes. Vulnerability is a function of the type, magnitude, and rate of climate change and variation to which a species is exposed, its sensitivity, and its adaptive capacity (IPCC 2007a, p. 89; see also Glick
Global climate projections are informative, and, in some cases, the only or the best scientific information available for us to use. However, projected changes in climate and related impacts can vary substantially across and within different regions of the world (for example, IPCC 2007a, pp. 8-12). Therefore, we use “downscaled” projections when they are available and have been developed through appropriate scientific procedures, because such projections provide higher resolution information that is more relevant to spatial scales used for analyses of a given species (see Glick
Documentation of climate-related changes that have already occurred in California (Croke
In southern California, climatic variables affecting vernal pool habitats are most influenced by distance from the coast, topography, and elevation (Bauder and McMillian 1998, p. 64). As presence and persistence of Riverside fairy shrimp appear to be associated with precipitation patterns, draw-down factors, and other regional climatic factors, including aridity (Eriksen and Belk 1999, p. 71), the likely impacts of climate change on ecological processes for Riverside fairy shrimp are most closely tied to availability and persistence of ponded water during the winter and spring. Vernal pools are particularly sensitive to slight increases in evaporation or reductions in rainfall due to their relative shallowness and seasonality (Field
Additionally, localized climate-related changes may alter the temporal
As discussed above, climate projections produced through Climate Wizard predict a decrease in annual rainfall by 2050. For a species that depends on long-term filling of vernal pools, any decrease in rainfall amount could affect the persistence of the species and the quality of available habitat. However, such projections are not straightforward, because filling of vernal pools may also depend on local watershed characteristics not directly related to annual rainfall. Additionally, the climate projections do not take storm events into account that could provide for filling of vernal pools. Therefore, designation of a wide variety of vernal pool habitat types is necessary to buffer against the projected future impacts of climate change. We find the designation herein provides for the array of habitat to provide for the conservation of the species.
In accordance with section 3(5)(A)(i) and 4(b)(1)(A) of the Act and regulations at 50 CFR 424.12, in determining which areas within the geographical area occupied by the species at the time of listing to designate as critical habitat, we consider the physical or biological features essential to the conservation of the species and which may require special management considerations or protection. These include, but are not limited to:
(1) Space for individual and population growth and for normal behavior;
(2) Food, water, air, light, minerals, or other nutritional or physiological requirements;
(3) Cover or shelter;
(4) Sites for breeding, reproduction, or rearing (or development) of offspring; and
(5) Habitats that are protected from disturbance or are representative of the historical, geographical, and ecological distributions of a species.
We derive the specific physical or biological features essential for the Riverside fairy shrimp from studies of this species' habitat, ecology, and life history as described in the Critical Habitat section of the proposed rule to designate critical habitat published in the
Riverside fairy shrimp require vernal pool habitat to grow and reproduce. Their life cycle requires periods of inundation as well as dry periods (Ripley
Intact vernal pool hydrology (including the seasonal filling and drying down of pools) is the essential feature that governs the life cycle of the Riverside fairy shrimp. An intact hydrological regime includes seasonal hydration (during most but not all years) followed by drying out of the substrate to promote overwintering of cysts and provide conditions for a viable cyst bank for the following season. Proper timing of precipitation and the associated hydrological and soil processes in the upland watershed contribute to the provision of space for growth and normal behavior. Seasonal filling and persistence of the vernal pool are necessary for cyst hatching and successful reproduction of Riverside fairy shrimp (see “Sites for Breeding, Reproduction, and Rearing (or Development) of Offspring”, below).
To maintain high-quality vernal pool ecosystems, the vernal pool basin (a specific vernal pool and surrounding landscape) or complex and its upslope watershed (adjacent vegetation and upland habitat) must be available and functional (Hanes and Stromberg 1998, p. 38). Adjacent upland habitat supplies important hydrological inputs to sustain vernal pool ecosystems. Protection of the upland habitat between vernal pools within the watershed is essential to maintain the space needs of Riverside fairy shrimp and to buffer the vernal pools from edge effects. Having the spatial needs that create pools of adequate depth also supports the temporal needs of Riverside fairy shrimp, as deep pools provide for inundation periods of adequate length to support the entire life-history function and reproductive cycles necessary for Riverside fairy shrimp.
Vernal pools generally occur in complexes, which are defined as two or more vernal pools in the context of a larger vernal pool watershed. The local watershed associated with a vernal pool complex includes all surfaces in the surrounding area that flow into the vernal pool complex. Within a vernal pool complex, vernal pools are hydrologically connected to one another within the local geographical context. These vernal pool complexes may connect by either surface or subsurface flowing water. Pools and complexes are dependent on adjacent geomorphology and microtopography for maintenance of their unique hydrological conditions (Service 1998a, p. 23). Water may flow over the surface from one vernal pool to another (over-fill or overbanking), throughout a network of swales or low-point depressions within a watershed. Due to an impervious clay or hardpan layer, water can also flow and collect below ground, such that the soil remains saturated with water. The result of the movement of water through vernal pool systems is that pools fill and hold water continuously for a number of days, weeks, or months following the initial rainfall (Hanes
Impervious subsurface layers of clay or hardpan soils, combined with flat to gently sloping topography, inhibit rapid infiltration of rainwater and result in ponded water in vernal pools (Bauder and McMillian 1998, pp. 57-59). These soils also act as a buffer that moderates the water chemistry and rate of water loss to evaporation (Zedler 1987, pp. 17-30). In Ventura County, soil series known to support Riverside fairy shrimp include, but are not limited to, the Azule, Calleguas, Cropley, and Linne soil series. In Orange County, soils series include the Alo, Balcom, Bosanko, Calleguas, Cieneba, Myford, and Soper soil series. In western Riverside County, vernal pool habitat known to support Riverside fairy shrimp includes the Altamont, Auld, Bosanko, Cajalco, Claypit, Murrietta, Porterville, Ramona, Traver, and Willows soil series. In San Diego County, vernal pool habitat known to support Riverside fairy shrimp includes the Diablo, Huerhuero, Linne, Placentia, Olivenhain, Salinas, Stockpen, and Redding soil series. Soil series data are based on 2008 Soil Survey Data and are available online at:
Many fairy shrimp species are filter feeders with a diet that consists mostly of algae, bacteria, and other microorganisms (Parsick 2002, pp. 37-41, 65-70). In a natural vernal pool setting, these food items are readily available. Typically, an undisturbed, intact surface and subsurface soil structure (not permanently altered by anthropogenic land use activities such as deep, repetitive discing or grading), and the associated hydrogeomorphic processes within the basin and upland watershed, are necessary to provide food, water, minerals, and other physiological needs for Riverside fairy shrimp. Water temperature, water chemistry, and length of time that vernal pools are inundated are the important factors in the hatching and temporal appearance of Riverside fairy shrimp (Gonzalez
Ponding of vernal pool habitat (water) also provides cover and shelter for Riverside fairy shrimp. During the period when these habitats are inundated, water plays an important role in providing the necessary aquatic environment (shelter) for the fairy shrimp to complete its life-history requirements. Without water to protect them from desiccation, fairy shrimp would be unable to hatch, grow, mature, reproduce, and disperse within the vernal pool habitat (Helm 1998, p. 136; Service 1998a, p. 34; Eriksen and Belk 1999, pp. 71, 105). Additionally, the wet (ponding) period excludes plant and animal species that are exclusively terrestrial, providing a level of shelter from predation and competition for the fairy shrimp, which are adapted to short-lived, ephemeral wetland habitats.
The undisturbed soil bank also provides cover and shelter for fairy shrimp cysts during the draw-down period of the vernal pool habitat. The drying phase allows reproductive cysts to overwinter, as they lay dormant in the soil. Basin soils provide cover and shelter to Riverside fairy shrimp as the vernal pool dries out (Simovich and Hathaway 1997, p. 42; Eriksen and Belk 1999, p. 105). By maintaining the population in a dormant state, reproductive cysts and the undisturbed soil in which they rest protect Riverside fairy shrimp from predators and competitors during the vernal pool dry period. Cyst dormancy is an important life-history adaptation for surviving arid phases, and is important for synchronizing life cycles in unstable and ephemeral wetland habitats (Belk and Cole 1975, pp. 209-210). Like the wet period exclusion of terrestrial plants, the draw-down period excludes species that are exclusively aquatic (such as fish), providing shelter for specially adapted Riverside fairy shrimp.
Mature Riverside fairy shrimp are typically observed from mid-March through April (Eng
Because the length of time that pools remain filled in vernal pool ecosystems is highly variable, Riverside fairy shrimp have become adapted to some degree of unpredictability in their habitat (Eriksen and Belk 1999, pp. 104-105) and to a system where the requisite conditions are transitory. Depending on rainfall and environmental conditions, a vernal pool may fill and recede numerous times. Often, the pool may evaporate before Riverside fairy shrimp are able to mature and reproduce (Ripley
Researchers have found that only a small proportion of Riverside fairy shrimp cysts in the cyst bank hatch each time the vernal pool fills. Therefore, if the pool dries before the species is able to mature and reproduce, there are still many more cysts left in the soil that may hatch the next time the pool fills (Simovich and Hathaway 1997, p. 42). Simovich and Hathaway (1997, pp. 40-43) referred to this as bet-hedging and concluded that it allows fairy shrimp, including Riverside fairy shrimp, to survive in an unpredictable environment. Bet-hedging ensures that some cysts will be available for hatching when the vernal pools hold water for a period long enough for Riverside fairy shrimp to complete their entire life cycle. Thus, reproductive output is spread over several seasons for small aquatic crustaceans, such as fairy shrimp, living in variable environments. Allowing conditions within the above parameters to occur on a natural basis is essential for the survival and conservation of Riverside fairy shrimp.
Pools that support Riverside fairy shrimp are generally found in flat or moderately sloping areas, primarily in annual, disturbed (such as grazed or deep disced) grassland and chaparral habitats. The majority of complexes and pools that currently support Riverside fairy shrimp have experienced some level of disturbance, primarily from agriculture, cattle, and OHV activity.
Estimates of the historical distribution of Riverside fairy shrimp suggest that 90 to 97 percent of vernal pool habitat has been lost in southern California (Mattoni and Longcore 1997, pp. 71-73, 86-88; Bauder and McMillan 1998, p. 66; Keeler-Wolf
The conservation of Riverside fairy shrimp is dependent on several factors including, but not limited to, maintenance of areas (of sufficient size and configuration to sustain natural ecosystem components, functions, and processes) that provide appropriate inundation and ponding durations, natural hydrological regimes and appropriate soils, intermixed wetland and upland watershed, connectivity among pools within geographic proximity to facilitate gene flow among complexes, and protection of existing vernal pool composition and structure.
In a few locations, two species of fairy shrimp—San Diego fairy shrimp and Riverside fairy shrimp—are known to co-occur (Hathaway and Simovich 1996, p. 670). However, where these species do co-occur, they rarely have been observed to coexist as adults (Hathaway and Simovich 1996, p. 670). San Diego fairy shrimp are usually found earlier in the season than Riverside fairy shrimp, due to the Riverside fairy shrimp's slower rate of development (Hathaway and Simovich 1996, p. 675). Maturation rates are responsible for the sequential appearance of the species as adults in pools where they co-occur (Hathaway and Simovich 1996, p. 675). Neither species is found in the nearby desert or mountain areas, as temperature has been shown to play an important role in the spatial and temporal appearance of fairy shrimp.
Under the Act and its implementing regulations, we are required to identify the physical or biological features essential to the conservation of Riverside fairy shrimp in areas occupied at the time of listing, focusing on the features' primary constituent elements. Primary constituent elements are those specific elements of the physical or biological features that provide for a species' life-history processes and are essential to the conservation of the species.
Based on our current knowledge of the physical or biological features and habitat characteristics required to sustain the species' life-history processes, we determine that the primary constituent elements specific to Riverside fairy shrimp are:
(1) Ephemeral wetland habitat consisting of vernal pools and ephemeral habitat that have wet and dry periods appropriate for the incubation, maturation, and reproduction of the Riverside fairy shrimp in all but the driest of years, such that the pools:
(a) Are inundated (pond) approximately 2 to 8 months during winter and spring, typically filled by rain, and surface and subsurface flow;
(b) Generally dry down in the late spring to summer months;
(c) May not pond every year; and
(d) Provide the suitable water chemistry characteristic