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//CEMEX USA BLACK GAP WMA/ECLCC MULE DEER RESTORATION PROJECT UPDATE February 2, 2016 Mule deer numbers at Black Gap Wildlife Management Area (BGWMA) and El Carmen Land & Conservation Company-CEMEX USA (ECLCC) (adjacent property) have decreased since the late 1980s and remain relatively low compared to other areas of the Trans-Pecos, while in the past this area had some of the highest mule deer numbers in the Trans-Pecos. Obviously, drought has significant impacts on Trans-Pecos mule deer populations. However, the mule deer herd within the project area has never rebounded from the last prolonged drought of the late 1990s and early 2000s, when almost all other herds in the Trans-Pecos did. This area also received a second blow to the population with a more recent drought from 20102014, which further impacted population growth. Therefore, objectives of the mule deer restoration project are to (1) conduct a multi-year translocation project to increase the mule deer population within the BGWMA and ECLCC property long-term, (2) evaluate success of restoration effort, (3) monitor mortality and factors that affect survivability, and (4) document movements and home ranges in relation to release sites/methods (hard-release vs. soft- release) and habitat components. During February 910, 2015, we translocated 40 mule deer does from Elephant Mountain Wildlife Management Area using the helicopter net-gun method (Figure 1). Thirty four animals were collared with either GPS (16) or VHF (18) radio-collars. The soft-release method was used at BGWMA with 21 does being liberated, while 19 does were hard-released at ECLCC property. One doe died during transport to the ECLCC release site, which was radio-collared.

BLACK GAP WMA/ECLCC MULE DEER RESTORATION PROJECT UPDATE€¦ · document movements and home ranges in relation to release sites/methods (hard-release vs. soft- release) and habitat

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Page 1: BLACK GAP WMA/ECLCC MULE DEER RESTORATION PROJECT UPDATE€¦ · document movements and home ranges in relation to release sites/methods (hard-release vs. soft- release) and habitat

//CEMEX USA

BLACK GAP WMA/ECLCC MULE DEER RESTORATION

PROJECT UPDATE

February 2, 2016

Mule deer numbers at Black Gap Wildlife Management Area (BGWMA) and El Carmen Land & Conservation Company-CEMEX USA (ECLCC) (adjacent property) have decreased since the late 1980s and remain relatively low compared to other areas of the Trans-Pecos, while in the past this area had some of the highest mule deer numbers in the Trans-Pecos. Obviously, drought has significant impacts on Trans-Pecos mule deer populations. However, the mule deer herd within the project area has never rebounded from the last prolonged drought of the late 1990s and early 2000s, when almost all other herds in the Trans-Pecos did. This area also received a second blow to the population with a more recent drought from 2010–2014, which further impacted population growth.

Therefore, objectives of the mule deer restoration project are to (1) conduct a multi-year translocation project to increase the mule deer population within the BGWMA and ECLCC property long-term, (2) evaluate success of restoration effort, (3) monitor mortality and factors that affect survivability, and (4) document movements and home ranges in relation to release sites/methods (hard-release vs. soft-release) and habitat components.

During February 9–10, 2015, we translocated 40 mule deer does from Elephant Mountain Wildlife Management Area using the helicopter net-gun method (Figure 1). Thirty four animals were collared with either GPS (16) or VHF (18) radio-collars. The soft-release method was used at BGWMA with 21 does being liberated, while 19 does were hard-released at ECLCC property. One doe died during transport to the ECLCC release site, which was radio-collared.

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Figure 1. Route taken for transporting mule deer from EMWMA to BGWMA and ECLCC. Orange stars represent release sites.

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Survival Since release, estimated survival is 73% (Figure 2). Nine mortalities have occurred: 5 from mountain lion predation and 4 undeterminable causes, estimating a mortality rate of 27% (9/33). There are currently two possible mortalities that have yet to be investigated. If these two are true mortalities, then the survival rate will decrease to 67%. Figure 2. Cumulative Kaplan-Meier survival estimates of the BGWMA and ECLCC mule deer released in February 2015.

Preliminary Movements

Telemetry has been conducted >1×/week either by ground or airplane to help monitor movements and activities of the translocated mule deer. GPS radio-collars obtain locations of the mule deer’s movements every 3 hours, but this data is not accessible until the radio-collar is recovered (either after radio-collar automatically drops off the animal or if the animal dies). Obtaining locations on VHF radio-collared mule deer is either done by getting visuals or estimating locations while conducting aerial telemetry. Estimated locations of radio-collared deer (VHF and GPS) from both release sites were obtained in May (~ 3 months post-release), September (~ 7 months post-release), and January 2016 (~ 1 year post-release) during telemetry flights. In May 2015, all 19 deer from the BGWMA release were located; only 5 of the remaining 12 ECLCC deer were located (Figure 3). The 3 farthest north locations were from BGWMA deer; they were roughly 25–35 miles north of the soft-release pasture. During September 2015, 11 of 15 BGWMA deer were located and 3 of the 10 ECLCC deer were located (Figure 4). Of these deer they were either near or within the BGWMA/ECLCC boundaries. In January 2016, 13 of 14 BGWMA deer were located and 6 of the 10 ECLCC were located (Figure 5). The majority of deer located were either near or within the BGWMA/ECLCC

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Weeks Following Release

BGWMA/ECLCC Translocated Mule Deer Survival 1 Year Following Release

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boundaries with some residing in Mexico. It appears that the soft-release method decreases dispersal distances; however, even with some greater dispersal distances from the hard-released mule deer, they are finding good habitat across the landscape. We hope this will lead to better mule deer production/numbers in the future throughout an expansive area, not just the BGWMA/ECLCC complex. Figure 3. Estimated locations of radio-collared mule deer during May 1, 2015 telemetry flight.

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Figure 4. Estimated locations of radio-collared mule deer during September 21, 2015 telemetry flight.

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Figure 5. Estimated locations of radio-collared mule deer during January 2016 telemetry flights.

Of the 9 recovered radio-collars from mortalities, 3 were GPS radio-collars. Figure 6 illustrates movements of these does. White #3 and White #7 were hard-released at the ECLCC and Red #3 was soft-released at BGWMA. All 3 does moved outside of property boundaries into either private, federal (Big Bend National Park), or international (Coahuila, MX) lands. The area in Mexico is part of the CEMEX, El Carmen Project and lands are all under a conservation program.

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Figure 6. Locations of 3 GPS radio-collared does programmed to record GPS locations every 3

hours.

Population/Browse Surveys Spotlight surveys conducted at BGWMA this fall indicated a population increase from less than 300 mule deer in 2014 to about 400 in 2015. Fawn crops also increased from 32% in 2014 to 48% in 2015. In addition, several translocated does have been observed with fawns.

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Habitat evaluations conducted in 2014 and 2015 estimated that the BGWMA/ECLCC area could support significantly more deer with very low utilization rates of important shrub species eaten by mule deer. Future Management Actions We plan to translocate 60 more mule deer does this winter (February 2016) to augment the population at BGWMA/ECLCC. At least 50 more radio-collars (20 GPS and 30 VHF) will be deployed with this year’s translocation. Both GPS and VHF radio collars will continue to be used to monitor and assess survival, movements, and habitat preference. Weekly telemetry efforts will continue to be conducted over the next 1.5 years (until 2016-released GPS radio collars drop off animals in 2017). Timely investigations of each mortality will help us better understand causes of death and potential factors affecting population dynamics of the area. Data from GPS radio collars will be used to analyze finite movements (rates, patterns), travel corridors, and habitat utilization. Predator management efforts will continue to be implemented at crucial times (prior to translocation, fawning season, mountain lion depredations within immediate release) to improve survival. Continued Habitat Work In March 2015, the Texas Bighorn Society built three guzzlers on ECLCC and two on BGWMA, which all five were targeting not only bighorns, but mule deer and other wildlife. In the fall of 2015, Dallas Safari Club (DSC) and the Mule Deer Foundation (MDF) provided funding ($15,000 from DSC and $7,500 from MDF) for two additional guzzlers, one at each study site. Currently, CEMEX–ECLCC has established 23 permanent water sources distributed across the landscape, with plans to continue guzzler developments in key mule deer habitat, as well as continue habitat enhancement projects. We will also be refurbishing 13 old wildlife guzzlers and installing 2–3 new guzzlers at BGWMA. The BGWMA guzzler project was made possible through a gift of $15,000 from the MDF and Shell Petroleum Company, as well as a match of $45,000 from Texas Parks & Wildlife Department’s Pittman-Robertson funds for a total of $60,000. Thanks! Because of the many partnerships and generous donations we are making strides in bringing back mule deer numbers to levels that historically occurred throughout the lower Big Bend Region of western Texas and adjacent northern Coahuila, Mexico.