Conservation and Ecology of Mammals VI

Contributed Paper
ROOM: Room 220 – Ruidoso
SESSION NUMBER: 96
 

1:10PM Elk Selection for Vacant Predator Niches Favors Coexistence with Wolves And Cougars in Northern Yellowstone National Park.
Michel T. Kohl; Toni K. Ruth; Daniel R. Stahler; Mathew C. Metz; Douglas W. Smith; Daniel R. MacNulty
Most prey living in natural systems cope with multiple predators. These predators often hunt in different places or at different times, limiting prey escape options, and leading to questions about how prey manage conflicting predation pressures. Here we tested the hypothesis that differences in the spatial distribution and timing of predator activity provided vacant predator niches that serve as refugia for prey in a multi-predator environment. For example, cursorial predators may hunt in open areas during day whereas ambush predators hunt in forested areas at night. Thus, prey could select for risky places during the safe times provided by lulls in predator activity. We tested for this potential predator avoidance mechanism by quantifying adult female elk (n = 27) habitat selection in northern Yellowstone National Park within the first decade following wolf reintroduction (2000-2004). Wolves were crepuscular hunters that killed elk in flat, open areas, whereas cougars were nocturnal hunters that killed elk in rough, forested areas. This created two vacant predator niches (open-night and forested-day) that elk regularly utilized. Elk selected for the open-night niche when wolf activity was low, and for the forested-day niche when cougar activity was low. Although prey commonly use space and time to manage predation risk, this is the first study to identify how prey integrate these axes to simultaneously avoid multiple predators. Given that resource partitioning is common in predator communities, this avoidance mechanism may occur in a variety of ecological contexts. Moreover, theory predicts that increased predator diversity will improve ecological function. However, the ability of behaviorally-sophisticated prey to navigate multi-predator landscapes may minimize predation risk and its cascading ecological effects. Thus, our results suggest that a prey’s ability to exploit vacant predator niches may be an important process to consider when predicting the effects of predator reintroduction or recovery on ecosystems.
1:30PM The Jaguar in El Cielo Biosphere Reserve, Tamaulipas, Mexico
Rogelio Carrera-Trevino; Ivan Lira-Torres; Luis Martinez-Garcia; Martha Lopez-Hernandez
Information on the ecology of jaguars (Panthera onca) in “El Cielo” Biosphere Reserve in Tamaulipas, Mexico is scant and limited to anecdotic records in a handful publications. The objectives of our study were to: a) determine population density and structure of jaguars, b) compare their activity patterns with that of pumas (Puma concolor), c) ascertain potential prey relative abundance, and d) evaluate local resident’s perception on loss of domestic animals due to jaguar predation. Between April 2013 and April 2014 we conducted camera trapping with a total sampling effort of 8,580 camera trap days. Besides, we completed 136 semi-structured interviews among local residents to gather information on domestic animal losses attributed to jaguars and other carnivores. We identified eight different jaguar individuals during a complete year of camera-trapping, composed of four adult females, one juvenile female, two adult males and one juvenile male. We estimated a jaguar density of 5.9±1.3 jaguars/100km². Activity patterns for jaguars and pumas were similar as both were nocturnal and crepuscular in nature. The most abundant potential prey species for jaguars in the study site were Crax rubra, Cuniculus paca, Mazama temama, Odocoileus virginianus and Didelphis virginiana; while the rarest were Mephitis macroura and Procyon lotor. Interview results suggested that chickens, dogs, and house cats were the most consumed domestic animals from all reported losses by local residents (n=107). This study represents the first attempt to describe jaguar ecology in “El Cielo” Biosphere Reserve; however, there is a need of additional monitoring efforts to determine the current status of jaguars in a larger area in order to establish conservation strategies. Finally, this jaguar population may have an important role in maintaining the species in the Sierra Madre Oriental biological corridor connecting populations in Nuevo Leon and San Luis Potosí states in Northeastern Mexico.
1:50PM Fear of the Human “Super Predator” Reduces Feeding Time in a Large Carnivore
Justine A. Smith; Justin Suraci; Michael Clinchy; Ayana Crawford; Devin Roberts; Liana Zanette; Chris Wilmers
Large carnivores’ fear of the human “super predator” has the potential to alter their feeding behavior and result in human-induced trophic cascades. However, it has yet to be experimentally tested if large carnivores perceive humans as predators and react strongly enough to have cascading effects on their prey. We conducted a predator playback experiment exposing pumas to predator (human) and non-predator control (frog) sounds at puma (Puma concolor) feeding sites to measure immediate fear responses to humans and the subsequent impacts on feeding. We found that pumas fled more frequently, took longer to return, and reduced their overall feeding time by more than half in response to hearing the human “super predator”. Combined with our previous work showing higher kill rates of deer in more urbanized landscapes, this study reveals that fear is the mechanism driving an ecological cascade from humans to increased puma predation on deer. By demonstrating that the fear of humans can cause a strong reduction in feeding by pumas, our results support that non-consumptive forms of human disturbance may alter the ecological role of large carnivores.
2:10PM Habitat Use Patterns of Mountain Lions in Relation to Behavioral State: Implications for Connectivity
Laura C. Gigliotti; Marc R. Matchett; David Jachowski
Movement patterns and resource selection can be strongly influenced by the behavioral state of an animal. Changes in behavioral state can result in changes in habitat requirements; therefore, understanding habitat use during all behavioral states is important for management decisions. Mountain lions (Puma concolor) have experienced large-scale range contractions historically, but are beginning to recolonize much of their former range. Dispersal is critical in connecting current mountain lion populations and serves as a means of range expansion. We studied habitat use of GPS-collared mountain lions in the Charles M. Russell National Wildlife Refuge in the Northern Great Plains of Montana in relation to behavioral state. We identified dispersing individuals by calculating the total distance moved from the core of the Refuge. For both dispersing and non-dispersing individuals, we identified behavioral phases using behavioral change point analysis, and we classified each phase as nomadic or localized using net-squared displacement. We compared habitat selection between the different phases using step selection functions that included several environmental covariates. Dispersing mountain lions used areas of coniferous forest during nomadic phases and formed temporary home ranges during dispersal in riparian areas. For both nomadic and localized states, dispersing mountain lions selected areas near forested land. However, dispersing individuals had a large preferred range of distances to forested areas (0 – 7000 m) during nomadic periods, whereas temporary home ranges during dispersal were located closer to forests (< 1000 m). Non-dispersing mountain lions used rugged, low elevation areas containing coniferous forest during nomadic phases, and selected for deciduous forests and riparian areas during localized phases. Our results indicate differences in habitat use based on the behavioral state of mountain lions, and suggest that future models predicting connectivity of mountain lion populations could be improved by incorporating differences in habitat use based on behavioral phase.
2:30PM A Novel Application of Dynamic Occupancy Models with False Positive Errors to Quantify the Seasonal Use of Sugarcane Farmlands in Northern India by Tigers
Rekha Warrier; Barry R. Noon
Land-use change around protected areas (PAs) can significantly impact species conservation outcomes. This is especially true in the case of the Tiger (Panthera tigris), an endangered and wide-ranging large carnivore. Extant tiger populations predominantly occur within human dominated landscapes in India. These landscapes are characterized by the presence of tigers beyond PA boundaries where favorable land-uses provide resources and dispersal opportunities. Since conservation endeavors are myopically focused on PAs, tigers in these landscapes are additionally at threat from land-use alterations occurring outside PAs. A holistic conservation strategy therefore should also entail an understanding of the dependence of tigers on the larger landscape that PAs are embedded in and devising policies to prevent land-use alterations in these areas. We conducted occupancy surveys within 1200 sq.km. of matrix habitats separating two tiger reserves in the CTL. Sugarcane cultivation is the dominant land-use in the matrix of the CTL, followed by human settlements and riparian areas. Tiger presence-absence data were generated within ninety, 2.6 sq. km grid cells by interviewing farm owners resident within these cells, conducting tiger pug-mark surveys and using camera traps. We corrected for both false positive and false negative errors in these data to estimate dynamic habitat use probabilities of tigers. Preliminary results indicate high probability of false positive errors in interview data and high but seasonal use of sugarcane farmlands by tigers (Psi0=0.623 ; Se=0.06). Analyses are ongoing to determine the effects of specific spatial and temporal correlates on habitat use, habitat colonization and extinction probabilities of tigers. Results from this study will help in the formulation of a comprehensive land-use policy to complement ongoing tiger conservation efforts in the CTL.
2:50PM Refreshment Break
3:20PM Estimating Detection of Prey Items in Bobcat Diet Using an Occupancy Framework
Summer D. Higdon; Dana J. Morin; Jennifer L. Holub; David M. Montague; Michael L. Fies; Lisette P. Waits; Marcella J. Kelly
Many studies seek to understand bobcat diet ecology both individually and in the context of sympatric predator species. However, the value of diet information is dependent on accuracy. While some studies evaluate the impact of bias due to scat misidentification, few have assessed the effect of imperfect detection of diet contents on study results. We evaluated bobcat diet ecology in western Virginia and determined detection probabilities of diet items. We collected bobcat scat samples between June 2011 and May 2013 across all seasons using 16 established 5-km transects. We confirmed scat identifications genetically. To determine detection rates of diet items, we divided each scat sample into 5 approximately equal subsamples. We then identified diet contents and recorded diet items as present (1) or absent (0) in each subsample. For each scat, we evaluated detection probability for diet items by dividing the number of subsamples with the diet item present by the total number of subsamples (5). We also used an occupancy modeling framework to determine if the presence of one item in the diet influenced the detection of other diet items. White-tailed deer, birds, lagomorphs, voles, squirrels, mice and rats, and mast were the most common diet items found in bobcat samples. All diet items had imperfect detection probabilities, with lagomorphs having the highest detection probability (p = 0.84) and mice and rats having the lowest detection probability (p = 0.4077). We did not find any associations among diet items. Our results suggest traditional approaches to evaluating diet using scat may underestimate some items that are difficult to detect. In future studies, we suggest subsampling a subset of scats to determine detection probabilities, which can then be used to estimate uncertainty across all scat samples and provide a more accurate understanding of diet ecology.
3:40PM Landscape And Habitat Use for a Large Carnivore in the City: Use and Selection for Mountain Lions Around Los Angeles
Seth P. D. Riley; John F. Benson; Jeffrey A. Sikich
Although some species of wildlife can adapt to and even thrive in urbanized areas, many species are rare or absent there. Large carnivores have some of the largest spatial requirements of any animal, and they have generally been thought to be incompatible with cities. However, in and around Los Angeles, the second largest metropolitan area in the U.S., mountain lions (Puma concolor) still persist despite the significant challenges. At Santa Monica Mountains National Recreation Area, we have been studying the behavior, ecology, and conservation of mountain lions since 2002. Here we analyze mountain lion landscape use and selection across the complex urban landscape of southern California using more than 125,000 GPS locations from 30 collared animals over 14 years. In general, mountain lions were rarely in developed areas, as their home ranges consisted on average of just 3% urban and 10% unnatural areas (urban plus “altered open” areas such as golf courses, low density residential areas, landscaped parks, etc.). However, there was significant variation between age and sex classes, and between individuals. Adult females had the smallest percentage of urbanized areas, at 0.8%, whereas subadult males had the highest, at 3.6%. Two adult males, P22 and P41, lived in highly circumscribed parklands, and they had some of the smallest adult male home ranges (24 and 54 km2) ever documented, and in our study by far the greatest use of urban areas, at 17.4%, and unnatural areas, at 26.4%. Interestingly, patterns of resource selection were different, in that all age-sex classes strongly selected areas near urbanization, with the exception of adult males, which strongly selected chaparral and riparian woodland areas. Subadults and females may be taking advantage of deer presence near developed areas while avoiding adult males. These results have important implications for mountain lion conservation and management in urban landscapes.
4:00PM Feeding Ecology of Neotropical Jaguars: New Perspectives from Next-Generation Sequencing
Claudia Wultsch; Marta DeBarba; Lisette P. Waits; Howard Quigley; Marcella J. Kelly; Konstantinos Krampis
Landscape scale diet assessments of top predators can provide a powerful means of studying their ecology and monitoring availability of food resources across human-impacted landscapes. Jaguars (Panthera onca), the largest felids in the Western hemisphere, are apex and keystone predators, greatly impacting ecological communities. Jaguars are skillful hunters that opportunistically feed on a wide range of prey species, requiring standardized methodologies with a high taxonomic resolution to capture the whole dietary breadth. This study combines noninvasive genetic sampling and high-throughput taxon identification (i.e. DNA metabarcoding) using DNA extracted from field-collected fecal samples, an universal vertebrate primer to amplify mitochondrial 12S gene fragments (100bp) of prey DNA, and a blocking olinucleotide specifically designed to prevent DNA amplification of the host, jaguar. Specifically, our research objectives are to describe the composition of jaguar diet and characterize predator-prey relationships across multiple study sites in Belize, Central America representing different ecosystems with varying degrees of human impact, habitat loss, and degradation. We analyzed 287 jaguar fecal samples, and our results are consistent with previous jaguar diet studies, indicating that jaguar feeding habits are complex and change across different habitats and levels of human disturbance. However, the high-throughput sequencing and DNA metabarcoding approaches have improved our ability to provide accurate taxonomic identification of highly diverse diets, also detecting digested and rare prey items. By studying dietary food habits of these elusive top predators, we gain a better understanding of the ecology of near-threatened jaguars, and also gather valuable baseline data on regionally important prey species and complex tropical food webs, supporting conservation and management efforts with the goal to preserve ecosystem structure and functioning.
4:20PM Foraging Behavior of Coyotes Under Intraguild Predation Risk by Cougars: an Experimental Approach
Julie K. Young; Peter Mahoney
When mesopredators encounter carcasses belonging to a dominant apex predator, they must balance degrees of risk associated with detection against loss of fitness-enhancing benefits from kleptoparasitism. Subordinate predators may behaviorally mediate risk by restricting activity to low-risk times of day, increasing latency to consume caches to reduce encounter risk, or increasing vigilance behavior while at cached items. Alternatively, subordinate predators may spatially avoid risk altogether but also lose access to the resource. We tested whether a subordinate predator modified behavior or avoided risk when encountering large, cached prey items of a dominant predator by experimentally placing carcasses with and without cougar (Puma concolor) scat and urine and measured coyote (Canis latrans) use and behavior via camera traps. In our study system, cougars killed coyotes both as prey and in defense of cached prey, providing in excellent system to evaluate the influence of risks and rewards on foraging behavior of a subordinate predator. We found no effect of cougar scent on the latency to detection (Odds Ratio = 0.85, p = 0.70) nor time from first discovery to contact/feeding (Odds Ratio = 0.86, p = 0.85) on the carcasses. Coyotes spent 143% (p < 0.001) more time exhibiting vigilance behavior and 46% (p = 0.18) less time feeding when in the presence of cougar treatments once a carcass was located. Coyotes also spent 10% (p = 0.02) less time in a vigilance state in the cover of darkness. Yet, we found no support for an increase in the frequency of specific vigilance behaviors between treatments. Our results strongly indicate that coyotes are willing to capitalize on risky subsidies in the form of cougar caches and balance risk by increasing the duration and not the frequency of vigilant behavior. These findings improve our understanding of how subordinate predators co-occur with dominant predators.
4:40PM Threats to Fishing Cats and Smooth Coated Otters in Godavari Mangroves
Srikanth Mannepuri; Ananth Reddy
Godavari mangroves are a mangrove wetland in India’s Andhra Pradesh state and covers an area of 371 square km and nestling on the deltaic branch of river Godavari at Kakinada bay. These Mangroves might be supporting the largest number of Fishing Cats and Smooth-coated Otter in the East – Coast of India. As per the Forest Department census records, there is a deep decline (>75%) in the population of both the species during last one decade. Fishing cat (Prionailurus viverrinus) and smooth coated (Lutrogale perspicillata) are listed as vulnerable by IUNC. Our objective was to document the various threats faced by the fishing cats and smooth coated otters in this region. During 2014 -2017, initially we conducted indirect questionnaire survey and scientific survey in mangroves adjoining 42 villages. According to the questionnaire survey results the people in the mangrove adjoining villages are mostly depended on mangroves for wood and ichthyofaunal species. The southern part of mangroves are surrounded by commercial aqua ponds. The major diet of fishing cat and smooth coated otter comprises of fish, so we conducted scientific survey around the aqua ponds in 17 villages and found plenty of otter spraints and fishing cat scats near the aqua ponds based on repeated observations we placed hideouts at these areas and documented the kills of fishing cats and otters by electric snaring and hunting. After harvesting the aqua ponds fish farmers are releasing the untreated waters in to the mangrove creeks that pollutes the mangrove ecosystem where these threatened species are living. According to the 3 years study results Habitat loss, animal and human conflict, poaching and hunting are the major threats to mangrove mammals. We started an NGO called Guardians of earth foundation through this we are trying to protect these threatened species by creating awareness in people.

 

Contributed Paper
Location: Albuquerque Convention Center Date: September 27, 2017 Time: 1:10 pm - 5:00 pm