42
Appendices
This plot is uniquely situated on the urbanizing interface with Lucerne Valley to the south and
the Johnson Valley Open Area to the east; the Stoddard Valley Open Area is not too distant to
the west. It occurs in one of three tortoise aggregations found in the Ord-Rodman DWMA.
Documented threats include OHV impacts, cattle trespass, bisection by a major transmission line
inside a BLM-designated utility corridor, raven predation, tortoise collection and vandalism, and
feral dogs. Proactive management prescriptions given elsewhere in this Plan call for signing
boundaries in this area, fencing portions of the cattle allotment to prevent cattle trespass,
monitoring Camp Rock Road, raven management, route reductions, restrictions to development
of new utilities, increased law enforcement, and education of Lucerne Valley residents. The
monitoring program on this and replicated plots in the region should focus on the efficacy of
these and other conservation programs implemented by the Plan. (No #)
Several BLM permanent study plots are found at the DTNA, although like other plots, they have
not been regularly funded since the early 1990's. These plots are unique in that they occur in a
relatively protected, fenced area in which densities of more than 300 tortoises per square mile
were documented in the 1970's and mid-1980's, but where present densities are substantially
lower. Monitoring of this plot provides a unique opportunity to see if tortoises can naturally
recolonize protected habitats. The fenced DTNA is surrounded by existing impacts that likely
serve as “sinks” for tortoises that are relatively protected until they venture into adjacent,
unfenced areas. Some of these uses include sheep grazing, intensive OHV use, agriculture and
wind-blown dust from the west, indirect impacts associated with mining to the north, feral dog
problems both inside and outside the DTNA, release of captive tortoises, raven predation,
intentional vandalism of tortoises, and pet collection. Monitoring efforts should consider the
efficacy of route reduction, enforcing California City’s sheep grazing policy, increased law
enforcement, feral dog management plan, raven management, and education of visitors to the
area. (No #)
This study plot is located in the Fremont Valley, which is bounded to the north by the El Paso
Mountains, to the south by the Rand Mountains, to the east by Red Mountain, and to the west by
Koehn Lake. It is very similar to the DTNA plots in terms of observable disturbances, except it
does not occur within the relative protection of a fenced area. All the programs mentioned above
for the DTNA are also intended to recover tortoises in the Fremont Valley. Unique threats
include road kill along Garlock Road, the direct and indirect effects of spreading biosolids in the
desert, noise, vibration, and mortality effects of the nearby railroad. Monitoring of the study plot
and replicated plots in the Fremont Valley should test the efficacy of conservation measures in
bolstering tortoise populations in the northwestern portion of the Fremont-Kramer DWMA.
Like DTNA and Fremont Valley, the Fremont Peak study plot has experienced recent declines in
tortoise numbers, although fewer tortoises occurred when the BLM’s study plots were first
surveyed in the 1970's. Unlike all other study plots mentioned above, the Fremont Peak plot is
characterized as a salt bush scrub community (creosote bush scrub characterizes the other plots).
Sheep grazing was removed from the area in 1991, although threats persist: natural
recolonization of a population that has nearly been extirpated, raven and canid predation, effects
of roads (several bisect the plot), and the indirect effects of Highway 395, which is located
41
Appendices
several miles to the west. Conservation measures are recommended by this Plan that would
minimize impacts associated with these and other impacts. Additionally, it is recommended that
the pilot headstarting program occur in the vicinity of this plot, so that the beneficial effects of
that program may be indirectly gauged by reviving studies on this and replicated plots within the
region. (No #)
The spatial location of the plots given above fairly well covers the Fremont-Kramer DWMA and
southern portion of the Ord-Rodman DWMA, but does not adequately represent the Superior-
Cronese or Pinto Mountain DWMAs. The Army’s National Training Center at Fort Irwin, in
conjunction with USGS, has established permanent study plots at the Goldstone Deep Space
Communications Complex, in the Alvord Mountains, and elsewhere in the Superior-Cronese
DWMA. Valuable information may be collected by continuing studies on these or other plots to
be established. (No #)
There are no permanent plots in the Pinto Mountains, although Joshua Tree National Park has
such plots nearby. (No #)
Many proactive conservation measures have been recommended that can be tracked at the study
plots given above, however it will be necessary to gauge the success and failures of specific
conservation programs for their efficacy and modification through adaptive management. Some
of these follow (No #):
Raven Management Working Group
Within Year 1
Implementation Milestone
: At which time it is formulated, the BLM shall ensure that it has
appropriate personnel committed to serve on the raven management working group. (No #)
Establish two work groups to oversee management direction, review information, coordinate
with other agencies/groups, solicit funding for implementation of specific management
measures, and distribute information/data. The work groups shall meet annually or as needed to
discuss raven management actions. One work group would be an Interagency Task Force to
coordinate implementation of the program. This group would identify specific areas where
lethal removal would be implemented using the criteria outlined above. The other would be a
technical and policy oversight team to evaluate the progress of the Plan, interpretation of data,
and recommend changes in the overall program based on scientific data. This group would help
to determine what thresholds of predation and recruitment are necessary to trigger
implementation of a cessation of lethal actions. There shall be data sharing between adjacent
bio-regional plans and resource management plans. The goals of the work groups would be to (i)
increase efficiency, effectiveness, and scientific validity of raven management in the California
deserts, and (ii) ensure that future phases are developed and implemented in accordance with
results of research and monitoring outlined above. (DT-38)
The Implementation Team shall facilitate issuance of applicable salvage permits, of as long a
duration as possible, to participating utility companies to enable them to remove raven nests
from transmission lines and other facilities. (No #)
40
Appendices
Reduce the population density of ravens and number of birds that may take tortoises by reducing
the availability to ravens of solid wastes at sanitary landfills. Reduce raven access to organic
wastes at landfills: (i) ensure effective cover of waste multiple times each day (either <
six (6)
inches cover or complete cover of garbage with tarps temporarily), (ii) erect coyote-proof
fencing, (iii) render raven-proof all sources of standing water at the landfill, and (iv) keep truck
cleaning areas and temporary storage facilities clean and free from organic wastes and standing
water. (DT-30)
Reduce the availability to ravens of organic wastes outside of landfills. Take the following
steps: (i) Encourage the use of self-closing trash bins at transfer stations and roadside rest stops,
and behind restaurants, gas stations, and grocery stores; use raven-proof garbage drums at houses
and other facilities; and avoid use of plastic bags for street-side pick up in residential areas; (ii)
Encourage livestock operators to reduce availability of cattle feed, carcasses, afterbirths, and
insects at feedlots and dairy farms; (iii) Use public education and other means to reduce the
number of citizens who purposely feed ravens or who inadvertently do so by leaving pet food out
where ravens can easily access it; and (iv) clean up illegal dump sites that contain organic
wastes. These educational efforts should include, but not be limited to, business and agriculture.
(DT-31)
Reduce the population density of ravens and number of birds that may take tortoises by reducing
the availability of water to ravens while being mindful of the needs of other species. (DT-33)
Reduce the impact ravens have on tortoise populations at specific locations by removing raven
nests. Remove raven nests (i) in specific areas where raven predation is high and tortoise
populations are targeted for special management, and (ii) do so during the egg-laying phase of
the raven’s breeding cycle. Any nestlings found should be euthanized using standard humane
measures. (DT-34)
Avoid constructing new nesting structures and reduce the number of existing nesting structures
in areas where natural or anthropogenic substrates are lacking. Reduce availability of nesting
sites by observing the following. (i) Within and adjacent to DWMAs, prevent the construction of
new structures (e.g., power towers, telephones, billboards, cell phone towers, open warehouses
or shade towers, etc.) where alternative natural nesting substrates (e.g., Joshua trees, cliffs) do
not already exist within approximately 2 miles. (ii) If they must be built, design such structures
in such a way as to prevent ravens from building nests on them. (DT-35)
Remove unnecessary towers, abandoned buildings, vehicles, etc., within tortoise management
areas that may serve as nesting substrates unless natural structures are in abundance. (DT-35)
Remove ravens that are known to prey on tortoises. Selectively shoot individual ravens in areas
of high tortoise predation. Ravens will be shot by rifle or shotgun if they show a likelihood of
preying on tortoises (e.g., tortoise shells showing evidence consistent with raven predation found
beneath or within approximately 1 mile a nest or perch). Ravens will be trapped and humanely
euthanized where shooting is not possible (e.g., on powerlines or in residential areas) or
38
Appendices
unsuccessful. Young ravens found in nests of removed adults will be euthanized humanely if
they can be captured safely. Poisoning with DRC-1339 or other appropriate agent may be used
against targeted ravens in these limited areas if it is shown by results of the research proposals
discussed below to be safe for other animals. Poisoned carcasses will be removed if they can be
located. (L-1)
Facilitate recovery of critically threatened tortoise populations by removing ravens from specific
areas where tortoise mortality from several sources is high, raven predation is known to occur,
and the tortoise population has a chance of benefitting from raven removal. Remove all ravens
foraging within specific areas (e.g., Desert Tortoise Research Natural Area, DWMAs, pilot
headstarting sites, etc.) of historically high tortoise mortality and raven predation, particularly
where demographic analyses indicate that juvenile survivorship has been unusually low. Ravens
will be shot by rifle or shotgun if they are found foraging, hunting, roosting, or nesting within
0.5 miles of the specific targeted area. Where shooting is not possible (e.g., on powerlines or in
recreation and residential areas), ravens will be poisoned (if shown by the research programs
recommended below to be safe) or trapped and humanely euthanized. Young ravens found in
nests of removed adults will be euthanized humanely if they can be captured safely. (L-2)
Determine behavior and ecology of ravens as they pertain to predation on tortoises. Data will be
collected by direct observations, radio tracking, diet analysis, wing tagging, and non-invasive
behavioral manipulations. (R1)
Conduct regional surveys of the California deserts to locate and map ravens and their nests and
communal roosts. Inventories would include private and public lands. Project proponents and
other interested parties would contribute funds to a coordinated surveying program that would
concentrate both on specific sites and broad regional patterns. (R2)
Methods will be developed, tested, and implemented to determine effectiveness of and need for
raven removal efforts for enhancing recruitment rates of juvenile desert tortoises into adult age-
classes. (R-3)
Determine efficacy and cost of shooting as a method of eliminating raven predation and
increasing tortoise survival. Data have already been collected and partially analyzed. (R-4)
Determine if eating hard-boiled eggs may adversely impact animals other than ravens laced with
the avicide DRC-1339. (R-5)
An experiment should be conducted concerning methyl anthranilate (a non-toxic, grape-flavored
food additive, but it is disliked by several species of birds) to determine if: (i) ravens are repelled
by the chemical; (ii) it can be applied efficiently at landfills and other raven concentration sites,
and on sources of water used by ravens (e.g., septage ponds, stock tanks, etc.); (iii) its repeated
application prevents ravens from using the resource (e.g., garbage, water, etc.), and (iv) if
methiocarb (Avery et al. 1993, Conover 1984), carbachol (Avery and Decker 1994, Nicolaus et
al. 1989) or other compounds work better than methyl anthranilate. (R-6)
39
Appendices
Determine if: (i) raven dependence on human-provided perches and nest sites aids hunting,
nesting, and overall survival; (ii) modifying raven perches, roost sites, and nest sites on a
localized basis is an effective way of reducing raven predation on tortoises; and (iii) removal of
raven nests early in the breeding cycle will prevent ravens from renesting in that season. (R-7)
Determine: (i) if live trapping is a cost effective means of catching ravens, (ii) the relative
effectiveness of different live trapping techniques, (iii) where ravens can be relocated practically
and legally, and (iv) if relocated ravens will return to the capture site or other desert tortoise
habitat. (R-8)
Develop a demographic model of raven populations to predict the effect various management
alternatives might have on raven populations. (R-9)
Determine the extent ravens use commercial and municipal compost piles, then develop and test
modifications to composting practices to make them inaccessible to ravens if a problem exists.
Develop and test other methods to prevent ravens from accessing food and waste items. (R-10)
Determine whether availability to ravens of anthropogenic sources of water could be reduced by
modifying sewage and septage containment practices in three possible ways: (i) covering the
water, (ii) altering the edge of the pond with vertical walls, (iii) placing monofilament line or
screening over the entire pond or (iv) adding methyl anthranilate, or other harmless taste
aversive chemicals to standing water sources. Emphasis should be placed on the reduction of
water availability during the spring, when ravens are nesting, and summer, when water demands
for ravens are high but natural sources are low. (R-11)
Monitor both raven status and effectiveness of management actions at reducing predation rates
on juvenile tortoises. (DT-39)
Revegetation
Within Year 2
Implementation Milestone
: Within two years of incidental take authorization, the
Implementation Team shall see that a standard, programmatic revegetation plan is developed and
available to project proponents who are required to revegetate pipelines and other areas as a
result of other plan prescriptions. (No #)
The following guidelines are recommended for revegetation in DWMAs: Revegetation is the
means by which (a) soil surfaces are stabilized (wind and water erosion control); (b) future
vehicle use is minimized or eliminated in areas to be revegetated; (c) future vehicle use is
minimized or eliminated for travel from the right-of-way into adjacent, undisturbed areas
(minimize impacts associated with increased or new access); (d) the spread of exotic weeds is
curtailed; and ultimately (e) habitat for the target species (desert tortoise in this case) is restored
(see success criteria discussion given in Section 3.3.4). (DT-11)
A standardized revegetation plan should be developed by the Implementation Team or its
appointee and applied equitably throughout DWMAs.A technical advisory team of regulatory
42
Appendices
personnel, restoration experts, knowledgeable utilities personnel, and others should be assembled
to devise and write the revegetation plan. (DT-11)
Silver Lakes Association
Within Year 1
Implementation Milestone
: Within one year of incidental take authorization, the Implementation
Team shall initiate a meeting with the Silver Lakes Association to determine the best way to
minimize impacts of that community to the adjacent DWMA. (DT-22)
Within Year 2
Implementation Milestone
: Within two years of incidental take authorization, following
discussions with the Silver Lakes Association, the Implementation Team shall implement
protective measures identified during those discussions. Follow-up studies and/or monitoring
will be implemented as per the schedule identified during discussions. (DT-22)
The Plan proposes that a working group be established by the Implementation Team to work
with the Silver Lakes Association and others to minimize the OHV impacts associated with that
community on the Fremont-Kramer DWMA, which occurs immediately to the west. Potential
solutions include installing a fence line along the western boundary of the community or
developing an intensive educational program to minimize and eventually eliminate the impact.
The efficacy of either of these approaches must be monitored and adaptive management applied.
(DT-22)
Tortoise: Disease
Within Year 1
Implementation Milestone
: Within one year of incidental take authorization, the Implementation
Team shall designate one or more of its members to interface with the Management Oversight
Group, most likely in the capacity of MOG Techincal Advisory Committee (MOG TAC)
member, and continue to be involved, particularly with regards to disease research. (DT-16)
Disease research is encouraged, and coordination between the Implementation Team and the
appropriate MOG contact should be maintained. Any breakthrough relative to disease
management should be incorporated into the West Mojave Plan through adaptive management
provisions. (DT-16)
At this time, the Plan relies on the Implementation Team adopting disease monitoring protocols
as they are identified and endorsed by pertinent experts and, likely, the Management Oversight
Group. (DT-17)
Tortoise: Disposition
During the Life of the Plan
Implementation Milestone
: The Implementation Team shall consider the need to establish
tortoise translocation areas if tortoises displaced as a result of plan implementation are not
accommodated through identified translocation guidelines. (No #)
19
Appendices
If the Implementation Team determines that the above [tortoise disposition] scenarios are not
accommodating all wild tortoises removed from impact zones where there is permanent loss of
habitat, then it should consider establishing translocation sites into which animals can be placed.
(No #)
Weeds
Within Year 2
Implementation Milestone
: Within two years of incidental take authorization, the
Implementation Team shall meet with appropriate weed management groups to begin
discussions of funding, coordinating, encouraging, implementing, and facilitating weed
abatement/management programs that contribute to the conservation of plant or animal species
covered by the Plan. (DT-40)
The Implementation Team will cooperate with known weed abatement specialists and
organizations (including the Kern County Weed Management Agency, the Mono/Inyo Weed
Management Area, the Mojave Weed Management Area, and the California Exotic Pest Plant
Council) to fund, coordinate, encourage, implement, and facilitate weed abatement/management
programs that contribute to the conservation of plant or animal species covered by the Plan. (DT-
40)
Documents you may be interested
Documents you may be interested