Progress 07/01/12 to 06/30/15
Outputs
Target Audience:Our target audiences were interested sportsmen, research scientists, and biologists from Nevada and other agencies charged with managing popualtions of migratory ungulates, especially mule deer. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?We trained multiple undergraduate students as technicans and provided experience with capture and handling of wild ungulates in addition to learning rigorous methods for data collection in the field. Those student participated in everything from capture and handling of mule deer to collection of samples, radio tracking, and performing necropsies in the field. How have the results been disseminated to communities of interest?We have given multiple talks at public and professional meetings including the American Society of Mammalogists and The Wildlife Society as well as presentation before the Nevada Board of Wildlife Commissioners and other sportsman's organizations. What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
Data collection was completed. the graduate student is currently writing and analyzing data, while concurrently working for Nevada department of Wildlife. Since the graduate student was employed by NDOW, producing products has slowed a bit. We are still working on those data, however, and we hope to have papers submitted within the next few months. The student has given multiple professional presentations on this research to the public and at scientific meetings.
Publications
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Progress 10/01/13 to 09/30/14
Outputs
Target Audience: State willdife agencies including Nevada Department of Wildlife, who will use the information obtained from this research to improve population management of migratory mule deer in the Great Basin Ecosystem. In addition, the target audience is federal land management agencies that manage lands that are traversed and are critical pathways to migratory ungulates and the mining industry to provide information on corridors used by mule deer in association with mining activities adjacent or encompasing migratory corridors. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided? We provided several opportunities for training and professional development including: 1 masters level graduate student, 1 PhD level graduate student, two seasonal field techninicans from the University of Nevada -Reno, and multiple undergraduate training and volunteer experiences for students in the Natural Resources and Environmental Sciences Program. How have the results been disseminated to communities of interest? The Western Section of the Wildlife Society Annual Meeting in Reno, NV January 2014. We have presented results to NGO's including Nevada Bighorns Unlimited, Nevada Land Trust, and various public media outlets. Nevada Department of Wildlife is currently using data collected during this project to improve management of mule deer herds as well as in association with mitigation efforts with the mining industry relative to migratory corridors used by mule deer. What do you plan to do during the next reporting period to accomplish the goals? Those data will be critical to the identification of important migratory corridors and the specific habitat variables important for mule deer in those ranges. The models and output maps derived from these analyses will be helpful to management agencies that are tasked with determining crucial levels of habitat importance and delineating migratory corridors of these migratory ungulates. Additionally, the final data collected from GPS collars will be used to produce resource selection functions (RSFs) to further identify critical components of mule deer migration habitats and potential impediments to connectivity.
Impacts
What was accomplished under these goals?
We have radio-collared approximately 600 mule deer distributed across several study areas throughout Nevada to monitor and determine causative agents for declines in mule deer populations related to nutrition, environmental conditions, habitat use, migration, dispersal, and predation in adult and juvenile mule deer. The preliminary results from this study has contributed to the better understanding of landscape scale habitat alterations in the form of mining developments, wildfire disturbance, and urban encroachment as well as our better understanding of mitigation measures to alleviate these disturbances. The research we have conducted on mule deer during 2013 and 2014has direct management implications on the health and nutritional condition of mule deer herds across the state. We have collected nutritional information on > 500 mule deer in 3 major study areas across the state. We continue to collect fine-scale movement data on > 300 adult mule deer in three study areas across Nevada. Energetics modeling will be included upon final acquisition of GPS collar information. We continue to monitor and quantify predation and other related causes of mule deer population declines by investigating > 135 mortality events during 2013 and 2014.
Publications
- Type:
Journal Articles
Status:
Awaiting Publication
Year Published:
2015
Citation:
Blum, ME, KM Stewart, and C Schroeder. 2015. Effects of large scale gold mining on migratory behavior of a large herbivore. Ecosphere. In Press.
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Progress 01/01/13 to 09/30/13
Outputs
Target Audience: Nevada Department of Wildlife - Biologists Carl Lackey, Jeremy Lutz, Caleb McAdoo, Mike Cox (we provided survival data and estimates for population modeling) NGOGroups - Nevada Bighorns Unlimited (provided additional funding, used our research progress report in monthly newsletter) Nevada Lands Trust (We provided input on wildlife migration corridors in Carson Range for land trust project) Federal Land Management Agencies - Bureau of Land Management, USDA Forest Service PublicOutreach - Tahoe Quarterly popular article http://tahoequarterly.com/2014/01/nevada-california-deer-herd-at-a-crossroads/ Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided? We provided several opportunities for training and professional development including: 1 masters level graduate student, 1 PhD level graduate student, two seasonal field techninicans from the University of Nevada -Reno, and multiple undergraduate training and volunteer experiences for students in the Natural Resources and Environmental Sciences Program. We also hosted a workshop for training and development in the modeling and analysis of movement data using advanced statistical packages. How have the results been disseminated to communities of interest? We have provided several outlets to disseminate information collected as part of this study. We have presented results at both regional and national professional conferences including: 1)The Wildlife Society Annual meeting October 2013 Milwaukee, WI, 2) American Society for Mammalogists 93rd Annual meeting June 2013 Philadelphia, PA, 3) 10th Biennial Deer and Elk Workshop, May 2013, Missoula, MT4) The Western Section of the Wildlife Society Annual Meetingin Reno, NV January 2014. Wehave presentedresults to NGO's including Nevada Bighorns Unlimited, NevadaLand Trust,and various public media outlets. What do you plan to do during the next reporting period to accomplish the goals? We will use movement data derived from GPS-satellite collars as well as VHF collars to determine the migratory status, survival rates,and to estimate seasonal migration distances in each population of mule deer. Additional analyses will attempt to parse out the remaining variation by including more specific individual covariates related to body condition including Normalized Difference Vegetation Index (NDVI) and average previous snow depth in each study area as contributing factors. In addition to collecting GPS fixes, these collars also have the ability to detect differences in activity rate (foraging activity vs. resting bouts) even when animals are not making large movements. Those activity monitors detect changes in activity by recording the angle of the collar every 15 minutes. By summarizing this activity data on a daily basis, we can infer and quantify relative time spent doing various activities and report an activity budget. Those data will be used to parameterize a model estimating energetic costs of migration for different migration strategies. In addition to analyzing movement data for energetic models, we will use Brownian BridgeMovementModels (Sawyer et al 2009) toidentifyseasonal habitat use, transitional ranges, and stop-over sites using the original approach developed byHorne et al. (2007). Those data will be critical to the identification of important migratory corridors and the specific habitat variables important for mule deer in those ranges. The models and output maps derived from these analyses will be helpful to management agencies that are tasked with determining crucial levels of habitat importance and delineating migratory corridors of these migratory ungulates. Additionally, the final data collected from GPS collars will be used to produce resource selection functions (RSFs) to further identify critical components of mule deer migration habitats and potential impediments to connectivity.
Impacts
What was accomplished under these goals?
We have radio-collared approximately600 mule deer distributed across several study areas throughout Nevada to monitor and determine causative agents for declines in mule deer populations related to nutrition, environmental conditions, habitat use, migration, dispersal, and predation in adult and juvenile mule deer. The preliminary results from this study has contributed to the better understanding of landscape scale habitat alterations in the form of mining developments, wildfire disturbance, and urban encroachment as well as our better understanding of mitigation measures to alleviate these disturbances. Juvenile survival varied markedly across study areas and between years. In general juvenile survival was about 20-35% higher during winter 2012 when compared to winter 2011 in all study areas. Winter conditions for capture year 2013 were harsh in the eastern and central regions and juvenile survival in those study areas were significantly lower, which likely is a reflection of these cold temperatures and poor winter foraging conditions for juvenile mule deer. Overall, male survival was significantly lower than for females across all study areas and years. The preliminary results from our known-fate survival analysis indicated that juvenile survival is strongly influenced by body condition, sex, and the severity of winter conditions between January and April. Animals in poor body condition were less likely to survive than animals in good body condition across all three study areas and for both adult and juvenile marked individuals. We also used previous summer precipitation as an index to forage quality however, this covariate did not enter the top competing models for survival in this population. We think that the variation in body condition that is highly influencing survival rate is largely accounting for most of the variation in forage quality, thus previous summer precipitation cannot fully explain that increased body condition. Alternatively, we may not be accounting for other sources of variation in forage conditions such as degraded ranges in some areas, or the influence of snow conditions on summer ranges in previous years. In addition to body condition and winter severity, migrations distance also contributed to the explained variation in survival. The primary source of mortality were “unknown” fates largely due to difficulty in accessing mortalities in a timely manner, and difficulty in differentiating between scavenging event and true sources of mortality. Of the mortality sources known or “likely to have occurred” the primary cause of mortality was predation by mountain lions or coyotes (which were lumped into predation events overall). Predation accounted for between 19.8% and 29.8% of the mortalities we collected depending on study area. In general, the Carson study area exhibited higher rates of human-caused mortality attributed to road-kills or other injuries sustained compared to other study areas. We attribute this in large part to the high degree of fragmentation occurring on winter and summer ranges through increased human development of landscapes and increases in urban and tourism traffic to the Tahoe Basin and Carson City Areas. The number of deer exhibiting a strong migratory pattern varied distinctly in each study area. In general, mule deer in the Ruby Mountain study area were highly migratory with about 85% of radio-collared mule deer making at least one long-distance movement between their winter and summer ranges . Deer in the Simpson Park study tended to exhibit a resident strategy through 2012, while deer in the Carson Range exhibited a mixed strategy of resident and migratory behaviors. We hypothesize that extremely mild winter weather conditions during 2012 may explain the differences in migratory patterns and resulting mixed migration strategy of this deer herd. We will continue to monitor and analyze the movement data as we collect the final year of GPS collar data transmissions. The research we have conducted on mule deer during 2013 has direct management implications on the health and nutritional condition of mule deer herds across the state. We have collected nutritional information on > 500 mule deer in 3 major study areas across the state. We continue to collect fine-scale movement data on > 300 adult mule deer in three study areas across Nevada. Energetics modeling will be included upon final acquisition of GPS collar information. We continue to monitor and quantify predation and other related causes of mule deer population declines by investigating > 135 mortality events during 2013.
Publications
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