INDIRECT EFFECT OF PREDATORS ON NESTING BIRDS

• Sponsoring Institution: State Agricultural Experiment Station
• Project Status: TERMINATED
• Funding Source: STATE
• Reporting Frequency: Annual
• Accession No.: 1000553
• Project No.: UTA01126
• Project Start Date: Jul 25, 2013
• Project End Date: Jun 30, 2018

Project Director
Conover, M.

Recipient Organization
UTAH STATE UNIVERSITY
(N/A)
LOGAN,UT 84322

Performing Department
Wildland Resources

Non Technical Summary
Direct and Indirect Effects of Avian Predators on the Nesting Success of Ducks and Pheasants Justification Densities of ravens, magpies, and gulls have increased dramatically in the West during the last few decades due to changed caused by humans. Garbage dumps, road kills, and other sources of human food allow more of these birds to survive the cold winters. Evergreen trees provide warm and safe roosting sites for ravens and magpies while man-made dikes and islands provide the same for gulls. All of these birds depredate the eggs of ground-nesting birds in the spring and kill the chicks in early summer. High rates of nest depredation reduce nesting success of greater sage-grouse, pheasants, and quail in the western U.S. The last few decades has also witnessed declining populations of ground nesting birds in Utah including ducks, pheasants, and sage-grouse and sharp-tailed grouse. Aside from the direct effects of nest depredation--loss of eggs and chicks--there is an indirect effect of nest predation which may have very significant effects on bird populations. Nesting birds may avoid nesting in high quality habitat if there is evidence that predators are abundant. Thus while the physical environment may remain intact, habitat with abundant predators or habitat which bird perceive as having abundant predators may be essentially lost to nesting birds. Many people in Utah enjoy bird hunting but fewer birds also means shorter bird seasons, fewer birds bagged, and more discouraged hunters. This lack of success also impacts Utah's farmers and ranchers because many of them charge hunters a fee for access to their property and the opportunity to hunt there. Likewise, public lands are often managed to maintain or increase avian populations and high depredation rates on birds complicate this task. This lack of nesting success due to high nest depredation rates means that there will be fewer birds to hunt and lower revenues for landowners. In this study, I will examine if 1) the nesting success of game birds is lower in areas where predators are abundant, 2) game birds forego nesting in good habitat when avian predators, such as magpies, ravens, and gulls, are too abundant, and 3) if nesting birds use both direct and indirect cues of predator abundance to assess the threat posed by avian predators. Direct cues would involve seeing or hearing predators while indirect cues would involve locating habitat features that are correlated with predators. For example, birds might avoid nesting near a power line because ravens and hawks use them for perch sites when hunting. Previous Work Direct negative effects of nest depredation on nesting productivity of birds are widely recognized. Local predator densities can affect both nest-site selection and productivity of ground-nesting birds, such as prairie grouse species, farmland birds, ducks, shorebirds, and passerines Indirect effects of nest depredation occur when-- because of the presence of predators--nesting birds avoid what otherwise would be considered high quality nesting habitat. For example, Dinkins et al. (2012) found that sage-grouse avoided nesting in areas where there were high densities of ravens, black-billed magpies, golden eagles, and hawks. Availability of food for chicks and risk of predation are two factors that influence the choice of breeding habitat by birds, and actual habitat choice has often been described as a trade-off between the two. That is, avian species may not nest in habitat that would be optimal for foraging if there is a high risk of predation. Avoidance of good nesting habitat because of a risk of predation can have a dramatic effect on nest success and chick survival, and effect the growth rates of avian populations. My past research funded by the Utah Agricultural Experiment Station has focused on how nesting birds avoid mammalian predators that track their prey using olfactory cues. In addition to several peer-reviewed publications, this research led to my authoring a book (Conover 2009). Here I am proposing to focus on how nesting birds avoid avian predators that visually track their prey and whether birds avoid nesting in what otherwise would be suitable nesting habitat when avian predators are abundant.

Animal Health Component

0%

Research Effort Categories

Basic

50%

Applied

50%

Developmental

(N/A)

Classification

Knowledge Area (KA)	Subject of Investigation (SOI)	Field of Science (FOS)	Percent
135	0820	1070	100%

Knowledge Area
135 - Aquatic and Terrestrial Wildlife;

Subject Of Investigation
0820 - Wild birds;

Field Of Science
1070 - Ecology;

Keywords

avian predators

ducks

nest depredation

pheasants

predator avoidance

predator prey interactions

ravens

Goals / Objectives
Objectives This study is designed to examine the direct and indirect effects of predators on nesting ducks and pheasants. I intend to answer the following questions. Objective 1. Determine and compare nest success rates of both ducks and pheasants in areas with varying concentrations of avian predators. Objective 2a. Determine effects of California gull colonies on both duck and pheasant nest densities at varying distances for it. Objective 2 b. Determine both duck and pheasant nest densities near power lines which are used as perches by avian predators. Objective 3. Determine effect of both direct and indirect cues of predators on both duck and pheasant nest densities.

Project Methods
jective 1. Determine and compare nest success rates of both ducks and pheasants in areas with varying concentrations of avian predators. During 2013, 2014, and 2015, I will locate all nesting ducks and pheasants in each plot. I will also construct a duck pseudo-nest using the methods described below to assess nest depredation rates in each plot. Each pseudo-nest will be constructed following the style of Ruzicka and Conover (2012) and contain a single chicken egg. Each egg will be placed on a treadle that is wired to a timing device that will record the exact time the nest is depredated (Borgo and Conover 2009). The nest bowl will be constructed from dry grass in the surrounding area. Adding a pseudo-nest to each plot will increase the scientific rigor of my research because I have no control over where ducks decide to place their nests. Whenever I refer to a nest in the methods section, I mean duck nests, pheasant nests, and pseudo-nests. I have nesting data for ducks at BRMBR-West prior to the creation of the gull colony; these data include the location of nests and nest fate (Frey 2005). I will replicate this prior study by locating duck nests at BRMBR and determine their fate by using the same methods employed earlier. I will locate nests by dragging a light chain to flush incubating hens from their nests. When they do so, I will search the area where the bird flushed until its nest is found. This procedure does not destroy the nests or damage eggs because the chain passes above the nest bowl; I have used it successfully in the past to locate duck nests without any adverse impacts (Frey et al. 2003, Frey 2005, Conover et al. 2005). For each nest, I will determine the species based on the hen that was incubating the nest. I will determine the clutch size, record the location of the nest using a GPS unit, and mark the nest by placing a small marker placed 10 m due south of the nest. I will record distance from the nest to the center of the gull colony using ArcMap GIS program. I will candle the eggs to assess the age of the embryos. Nests will be checked weekly from a distance to not disturb the hen until the nest's fate is determined (i.e. the nest is abandoned, depredated, or successfully produces a chick). I will determine which predators are depredating nests by placing a Cuddeback No FlashR motion-trigged infrared camera (Cuddeback, De Pere, Wisconsin) at each nest. These miniaturized cameras have a video recording system that monitors the fate of nests. Cameras will be camouflaged so that predators cannot use them to locate nests. The camera systems are equipped with an infrared illuminator, which allows the cameras to film at night without attracting the attention of mammalian predators. I have used these cameras in the past to determine which predators depredate nests (Ruzicka and Conover 2012). At each nest, I will use a cover board to measure both vertical and horizontal concealment of the nest. The cover board is a 10 X 10 cm white square with vertical and horizontal black lines spaced 1 cm apart so that they create 100 points where the vertical and horizontal lines cross. Horizontal concealment is measured by placing the cover board in the nest bowl perpendicular to the ground and counting the number of points that are obscured from view when I look at the nest bowl from a distance of 1.5 m and at a height of 1 m. This count will be repeated four time from each of the cardinal directions; the mean of the four values will be used a measure of horizontal cover. I will measure vertical concealment by placing the cover board in the next bowl so that is parallel to the ground. I will look down at the cover board from a height of 1.5 m and record the number of points that are concealed. I will also measure the height of the tallest plant within 1 m of the nest bowl and identify it to species. I have used these measurements in the past to record the characteristics of sage-grouse nests (Conover et al. 2010, Kirol et al. 2012). I will conduct point counts during the incubation period to assess local abundance of gulls and other avian predators at each nest site. Point counts will be ten minutes in duration during which all magpies, ravens, hawks, and eagles that are either seen or heard will be counted. Point counts will be conducted weekly for four weeks beginning as soon as a nest is discovered. To avoid disturbing the incubating hen, point counts will be conducted from a point 50 m away from a nest but within line of site of it. I will use standard distance-sampling techniques to count and record distance to all gulls, ravens, magpies, and raptors observed during points. All avian predators will be identified by species. I will record the distance from the nest to where the predator was first located. I will employ a 1,500 m rangefinder RE 1500 (American Technologies Network, San Francisco, California) in conjunction with a GPS unit to estimate distances directly. I have used these point-counts surveys in the past to assess the abundance of avian predators at sage-grouse nests (Dinkins et al. 2012). I will use several comparisons to assess whether the nest success of ducks and pheasants decline in areas where predator are abundant. First, I will compare numbers of gulls, magpies, ravens, and hawks seen during point counts conducted at successful nests (i.e., those that hatched at least one chick or duckling) to the number seen at depredated nests. In BRMBR-West, I will also compare how far away successful nests and depredated nests are located from the center of the gull colony. In BRMBR-East, I will compare the distance of success nests to depredated nests to the electrical power lines. I have data on the number of duck nests along the dikes of BRMBR, their locations, and the fate of each nest prior to the establishment of the gull colony on BRMBR. Hence, I will compare the location and fate of current duck nests to the location and fate of duck nests prior to when the colony was created. Objective 2a. Determine effects of California gull colonies on both duck and pheasant nest densities at varying distances for it. Objective 2b. Determine both duck and pheasant nest densities near power lines which are used as perches by avian predators. I will use several comparisons to assess if ducks and pheasants avoid nesting in areas where avian predators are abundant. I will determine the mean number of avian predators seen during point-counts conducted in each plot. I will also determine the mean distance of all plots in BRMBR-West to the center of the gull colony and all plots in BRMBR-East to the power lines. These will serve as the independent variables. For my dependent variables, I will calculate the density of ducks nests (number/ km2), pheasant nests, and all nests for each plot. I will test the data to determine if dependent variables are correlated with any of the independent variables. Objective 3. Determine effect of both direct and indirect cues of predators on both duck and pheasant nest densities. During the fourth year of the study, I will erect an abandoned raven nest in all of the BRMBR-West plots that are furthest from the gull colony (5-10 km away) and each BRMBR-East plots farthest from the power lines (250-350 m away). Raven nests are made of sticks, and I will place one nest in the highest tree located in these plots. Gulls and hawks defecate near their nests, and their defecations (secretions really) from their caeca are similar to white wash in Hence, I will collect caecal secretions from around gull nests in the gull colony and will use these to paint the abandoned raven nest and the vegetation beneath it white.

Progress 07/25/13 to 06/30/18

Outputs
Target Audience:Utah Division of Wildlife Resources Wyoming Land Conservation Initiative Wyoming Department of Game and Fish U.S. Bureau of Land Management U.S. Bear River Migratory Bird Refuge Private landowners Changes/Problems:This project has been completed. What opportunities for training and professional development has the project provided?Two M.S. students involved in this project have graduated. Several undergraduate students, who were seeking wildlife management degrees, were employed either during the summer or school year to collect and analyze the data. How have the results been disseminated to communities of interest?Presentations and reports were given to the Utah Predator Board, Utah Chapter of the Wildlife Society, Wyoming Game and Fish, Wyoming Animal Damage Management Board, Land Conservation Initiative, and the Western Association of Fish and Wildlife Agencies. What do you plan to do during the next reporting period to accomplish the goals?This project has been completed, but I will continue to analyze data and write the results for publication in peer-reviewed manuscripts.

Impacts
What was accomplished under these goals? I located 193 duck nests; 33% were cinnamon teal nests, 44% were mallard, and 23% were gadwall based on those nests that I was able to identify to species. Most nests (61%) were depredated; 34% successfully hatched at least one egg; and 6% were abandoned by the hen. The proportion of nests that were successful did not vary by duck species. Nest location within Bear River Migratory Bird Refuge (BRMBR), date nest was located, laying date, and clutch size did not vary among duck species. For this reason, data from all duck species were combined for further analysis. Distance to the nearest gull colony or potential perch site for a raptor did not differ between successful and unsuccessful duck nests. Density of duck nests did not differ based on distance to the nearest gull colony or potential perch site. Density of duck nests and nest success rates were both higher in nesting colonies of American avocets and black stilts than elsewhere. I was able to identify 26 predators conclusively because they were photographed while depredating a duck nest. Twenty-five were raccoons, nine by skunks, one by a coyote, and one by a California gull. There was no significance difference in the location of nests depredated by each of these species within the BRMBR. I stopped collecting data for this part of the study on July 1, 2018 and am now analyzing the data. The manuscript based on these data will be submitted to a peer-reviewed publication in the future. The other parts of this research project have resulted in several peer-reviewed publications and presentations. This project resulted in additional funding of more than $200,000 dollars from the Wyoming Animal Damage Management Board and Wyoming Game and Fish. Based on my research findings, the Bear River Migratory Bird Refuge modified their strategy to manage predators.

Publications

• Type: Books Status: Published Year Published: 2015 Citation: Conover, M. R., & Vail, R. M. (2015) Human Diseases from Wildlife. Boca Raton, Florida: CRC Press.
• Type: Journal Articles Status: Published Year Published: 2014 Citation: Dinkins, J., Conover, M. R., Kirol, C. P., Beck, J. L., & Frey, S. (2014). Greater sage-grouse (Centrocercus urophasianus) select habitat based on avian predators, landscape composition, and anthropogenic features. Condor: Ornithological Applications.
• Type: Journal Articles Status: Published Year Published: 2016 Citation: Roberts, A. J., Conover, M. R., & Vest, J. L. (2016). Environmental influences on wintering duck abundance and distribution at Great Salt Lake, Utah. Western North American Naturalist, 76, 18-26.

Progress 10/01/16 to 09/30/17

Outputs
Target Audience:Target Audience Utah Division of Wildlife Resources Wyoming Land Conservation Initiative Wyoming Department of Game and Fish U.S. Bureau of Land Management U.S. Bear River Migratory Bird Refuge Private landowners Changes/Problems:I have not located enough pheasant nests to make meaningful comparisons so I have stopped this line of research. For most of the other experiments, I need to collect data during the 2018 nesting season, which extends until mid-July. This will prevent me to write all of the papers until after this project officially ends. I will still write them, but after this project has come to a close. What opportunities for training and professional development has the project provided?I mentored my graduate student Ben Dana, who is working on this project. How have the results been disseminated to communities of interest?I published eight peer-reviewed publications in scientific journals during 2017; four of them were about this project. I gave one invited seminars on this topic. What do you plan to do during the next reporting period to accomplish the goals?I plan to continue locating duck nests at the U.S. Bear River Migratory Bird Refuge during 2018. Ben Dana will start writing his thesis. I will continue to write papers about this research topic. The project will end during 2018, and I will write a final report.

Impacts
What was accomplished under these goals? I located 38 duck nests and 0 pheasant nests during 2017. Most duck nests failed to hatch. Nest cameras revealed that raccoons and skunks were responsible for almost all failed nests. I received enough funding from Wyoming Animal Damage Management Board to continue examining the impact of ravens on sage-grouse. I started an experiment using exclosures of different sizes to determine how far away a predator can detect a bird's nest. I finished an experiment to assess whether birds avoid areas in the vicinity of badger burrows or raptor nests. Tree swallows, western meadowlarks, and sharp-tailed grouse exhibited a slight tendency to avoid sites near burrows and hawk nests, but the results were not statistically significant.

Publications

• Type: Book Chapters Status: Published Year Published: 2017 Citation: Lewis, R. J., Conover, M. R. (2017). Feeding a hungry world: threats to agriculture. In William C. Pitt, James C. Beasley, and Gary W. Witner (Ed.), Ecology and Management of Terrestrial Vertebrate Invasive Species in the United States (pp. 99-105). Boca Raton, Florida: CRC Press.
• Type: Journal Articles Status: Published Year Published: 2017 Citation: Conover, M. R., Roberts, A. J. (2017). Predators, predator removal, and sage-grouse: a review. Journal of Wildlife Management, 81, 7-15.
• Type: Journal Articles Status: Published Year Published: 2017 Citation: Dinkins, J. B., Lawson, B. K., Smith, K. T., Beck, J. L., Kirol, C. P., Pratt, A. C., Conover, M. R. (2017). Quantifying overlap and fitness consequences of migration strategy with season habitat use and a conservation policy. Ecosphere, 8(10).
• Type: Journal Articles Status: Published Year Published: 2017 Citation: Frank, M., Conover, M. R. (2017). Weather and prey availability affect the timing of fall migration of eared grebes (Podiceps nigricollis) from Great Salt Lake. Wilson Bulletin of Ornithology, 129, 98-111
• Type: Journal Articles Status: Published Year Published: 2017 Citation: F. J., Conner, M., C. M. R., T. T. (2017). Comparing urban and wildland bear densities with a DNA-based capture-mark-recapture approach. Human-Wildlife Interactions, 11, 50-63.
• Type: Journal Articles Status: Published Year Published: 2017 Citation: Peebles, L. W., Conover, M. R. (2017). Sage-grouse numbers rise following raven removal. Wildlife Society Bulletin, 41, 471-478.
• Type: Journal Articles Status: Published Year Published: 2017 Citation: Peebles, L. W., Conover, M. R. (2017). Winter ecology and spring dispersal of common ravens in Wyoming. Western North American Naturalist, 77, 293-308.
• Type: Conference Papers and Presentations Status: Other Year Published: 2017 Citation: Conover, M. R., The Wildlife Society Conference on Wildlife Damage Management, "Can ground-nesting birds hide from olfactory birds?," The Wildlife Society, Orange Beach, Alabama. (2017 - Present)
• Type: Conference Papers and Presentations Status: Other Year Published: 2017 Citation: Conover, M. R., The Wildlife Society, Conference on Wildlife Damage Managment, "Human diseases from wildlife," Thje Wildlife Society, Orange Bearch, Alabama. (2017 - Present)

Progress 10/01/15 to 09/30/16

Outputs
Target Audience:Target Audience Wyoming Land Conservation Initiative Wyoming Department of Game and Fish U.S. Bureau of Land Management U.S. Bear River Migratory Bird Refuge U.S. Fish and Wildlife Service Utah Predator Board Association of Fish and Wildlife Agencies Changes/Problems:Changes/Problems My Ph.D. student, Rob Lewis, abruptly quit during the middle of fall semester. I have replaced him by hiring Ben Dana as an M.S. student starting January, 2017. I am seeking additional funding to determine what proportion of ducklings are killed by predators. What opportunities for training and professional development has the project provided?Opportunities I have recruited M.S. student, Ben Dana, to determine if sage-grouse nesting success and grouse numbers increase in areas where ravens have been removed. Two undergraduate students helped collect and analyze data. How have the results been disseminated to communities of interest?Dissemination I published seven peer-reviewed publications in scientific journals during 2016; six of them were about this project. I also gave three invited seminars on this topic, one to the Western Association of Fish and Wildlife Agencies. I also published an article in the magazine Fair Chase to inform hunters and the general public about my research. What do you plan to do during the next reporting period to accomplish the goals?Plan of Work I plan to continue locating duck and pheasant nests at the U.S. Bear River Migratory Bird Refuge during 2017. Ben Dana will continue his work with ravens in Utah, Idaho, and Wyoming. The Journal of Wildlife Management asked me during 2015 to write a review paper on the impact of predators on the nest success of grouse. This review paper has now been accepted will be published during 2017.

Impacts
What was accomplished under these goals? Accomplishments I located 55 duck nests and 2 pheasant nests during 2016. Nineteen duck nests successfully hatched. Nest cameras revealed that raccoons and skunks were responsible for almost all depredated nests. I received enough funding from Wyoming Animal Damage Management Board to continue examining the impact of ravens on sage-grouse.

Publications

• Type: Journal Articles Status: Published Year Published: 2016 Citation: Borgo, J. S., Conover, M. R. (2016). Influence of shelterbelts on success and density of waterfowl nests within the Prairie Pothole Region of North America. Waterbirds, 39, 74-79.
• Type: Journal Articles Status: Published Year Published: 2016 Citation: Borgo, J. S., Conover, M. R. (2016). Visual and olfactory concealment of duck nests: influence on nest site selection and success. Human-wildlife Interactions, 10, 110-121.
• Type: Journal Articles Status: Published Year Published: 2016 Citation: Conover, M. R., Roberts, A. J. (2016). Declining populations of greater sage-grouse: where and why. Human-wildlife Interactions, 10, 217-229
• Type: Journal Articles Status: Published Year Published: 2016 Citation: Dinkins, J. B., Conover, M. R., Kirol, C. P., Beck, J. L., Frey, S. N. (2016). Effects of common raven and coyote removal and temporal variation in climate on greater sage-grouse nesting success. Biological Conservation, 202, 50-58.
• Type: Journal Articles Status: Published Year Published: 2016 Citation: Dinkins, J. B., Smith, K. T., Beck, J. L., Kirol, C. P., Pratt, A. C., Conover, M. R. (2016). Microhabitat conditions in Wyomings Sage-grouse Core Areas: effects on nest site selection and success. PLos ONE 11(3), e0150798.
• Type: Journal Articles Status: Published Year Published: 2016 Citation: Peebles, L. W., Conover, M. R. (2016). Effectiveness of the toxicant DRC-1339 in reducing populations of common ravens in Wyoming. Wildlife Society Bulletin, 40, 281-287.
• Type: Other Status: Published Year Published: 2016 Citation: Conover, M. R., Leopold, B. B. (2016). Human-wildlife conflicts  the natural resource issue of the 21st Century. (3rd ed., vol. 32, pp. 14-15). Fair Chase.
• Type: Conference Papers and Presentations Status: Other Year Published: 2016 Citation: Presentations Shilling, M. (Guest Speaker), Carman, J. G. (Author Only), Mateo de Arias, M. (Author Only), Sherwood, D. A. (Author Only), Dwivedi, K. K. (Author Only), Srivastava, M. K. (Author Only), Lawit, S. J. (Author Only), Components of Apomixis Workshop, "Differential gene expression in diploid sexual, diploid apomictic and triploid apomictic species of Boechera," International Plant & Animal Genome XXIV Conference, San Diego, CA. (January 9, 2016 - January 13, 2016)
• Type: Conference Papers and Presentations Status: Other Year Published: 2016 Citation: Presentations Conover, M. R., "Predators, predator control, and sage-grouse," Western Association of Fish and Wildlife Agencies, Sheridan, Wyoming. (2016 - Present)
• Type: Conference Papers and Presentations Status: Other Year Published: 2016 Citation: Presentations Conover, M. R., "Protecting duck nests from predators," Bear River Migratory Bird Refuge, Brigham City, Utah. (2016 - Present)
• Type: Conference Papers and Presentations Status: Other Year Published: 2016 Citation: Presentations Conover, M. R., Wildlife Damage Management Conference, "Can birds hide from olfactory predators?," The Wildlife Society, Gatlinburg, Tennessee. (2016 - Present)

Progress 10/01/14 to 09/30/15

Outputs
Target Audience:Target Audience Wyoming Land Conservation Initiative Wyoming Department of Game and Fish U.S. Bureau of Land Management U.S. Bear River Migratory Bird Refuge U.S. Fish and Wildlife Service Changes/Problems:Changes/Problems We have received enough funding from Wyoming to expand our research to include nesting sage-grouse. What opportunities for training and professional development has the project provided?Opportunities I received enough funding to examine the impact of ravens on sage-grouse. In Wyoming, USDA Wildlife Services uses the avicide, DRC-1339, to remove ravens at landfills during winter. I have recruited a Ph.D. student, Rob Lewis, to determine if sage-grouse nesting success and grouse numbers increase in areas where ravens have been removed. How have the results been disseminated to communities of interest?Dissemination One paper on this research was just accepted by the peer-review journal, HUMAN-WILDLIFE INTERACTIONS and two others were published by WATERBIRDS. My former graduate student, Jen Borgo, is the senior author on these papers and I am the junior author. What do you plan to do during the next reporting period to accomplish the goals?Plan of Work I plan to continue locating duck and pheasant nests at the U.S. Bear River Migratory Bird Refuge during 2016. The JOURNAL OF WILDLIFE MANAGEMENT has asked me to write a review paper on the impact of predators on the nest success of grouse. I am currently writing that paper. Rob Lewis will start monitoring the number of ravens roosting in Lincoln County. During 2016, he will assess how many ravens are killed by USDA Wildlife Services and what proportion of the raven population in the county have been removed. Lek counts will be used to determine how grouse numbers change in areas where ravens have been removed and in non-removal areas.

Impacts
What was accomplished under these goals? Accomplishments I located 45 duck nests and 4 pheasant nests during 2015 on the Bear River Migratory Bird Refuge. Only five duck nests successfully hatched. Nest cameras revealed that raccoons and skunks were responsible for almost all depredated nests. Two nests were depredated by gulls. Both of these were near a colony of California gulls. I received enough funding from Wyoming Game and Fish and Wyoming Animal Damage Management Board to examine the impact of ravens on sage-grouse.

Publications

• Type: Books Status: Published Year Published: 2015 Citation: Books Conover, M. R., Vail, R. M. (2015). Human Diseases from Wildlife. Boca Raton, Florida: CRC Press.
• Type: Other Status: Published Year Published: 2015 Citation: Refereed Journal Articles Borgo, J. S. (2015). Spatio-temporal patterns in the depredation of waterfowl nests in the Prairie Potholes region, USA. Waterbirds, 38, 133-142.
• Type: Other Status: Published Year Published: 2015 Citation: Refereed Journal Articles Conover, M. R., Dinkins, J. B., Ruzicka, R. E. (2015). Consequences of hunter harvest, winter weather, and increasing population size on survival of non-migratory Canada geese in Connecticut. Journal of Wildlife Management, 79, 1239-1245.
• Type: Other Status: Published Year Published: 2015 Citation: Refereed Journal Articles Frank, M. M., Conover, M. R. (2015). Thank goodness they got all the dragons: wildlife damage management through the ages. Human-Wildlife Interactions, 9, 156-162.
• Type: Other Status: Published Year Published: 2015 Citation: Refereed Journal Articles Keough, H. L., Conover, M. R., Roberts, A. J. (2015). Factors influencing nesting success of ferruginous hawks in the Uintah Basin, Utah. Journal of Raptor Research, 49, 161-173.
• Type: Other Status: Published Year Published: 2015 Citation: Refereed Journal Articles Mabray, S. T., Conover, M. R. (2015). Microhabitat selection by greater sage-grouse hens during brood rearing. Human-Wildlife Interactions, 9, 219-228.
• Type: Other Status: Published Year Published: 2015 Citation: Refereed Journal Articles Roberts, A. J., Conover, M. R. (2015). Breeding origins of northern shovelers (Anas clypeata) wintering on the Great Salt Lake, Utah. Wilson Journal of Ornithology, 127, 233-238

Progress 10/01/13 to 09/30/14

Outputs
Target Audience: Target Audience Wyoming Land Conservation Initiative Wyoming Department of Game and Fish U.S. Bureau of Land Management U.S. Bear River Migratory Bird Refuge Utah Division of Wildlife Resources Changes/Problems: Changes/Problems Wyoming is now dispersing baits treated with DRC-1339 at landfills to remove ravens. This provides us with an opportunity to assess how effective this method is at reducing raven densities and saving sage-grouse nests from depredation. Hence, we are currently putting radio transmitters on raven so that we can assess what proportion of the raven population has been removed. This spring, we will compare the proportion removed to the number of sage-grouse attending leks. What opportunities for training and professional development has the project provided? Opportunities Wyoming Game and Fish will remove ravens during 2015 at roost sites. We will be able to use this opportunity to determine if this method is successful in reducing raven densities in the spring and whether it reduces sage-grouse nest depredation. How have the results been disseminated to communities of interest? Dissemination We gave presentations to the Utah Division of Wildlife Resources, Utah Predator Board, Wyoming Game and Fish Department, and Utah and Wyoming Chapters of The Wildlife Society. We gave a copy of our duck data to the U.S. Migratory Bird Refuge. They were surprised that 75% of their duck nests are depredated. What do you plan to do during the next reporting period to accomplish the goals? Plan of Work Obj. 1. We will assess raven, crow, magpie, hawk, and eagle numbers a random points during 2015. We will locate duck and pheasant nests and determine the proportion that are depredated. We will determine which predatory species depredated each nest by placing a camera at each nest site. Objective 2a. We will visit gull colonies at the U.S. Bear River Migratory Bird Refuge to count the number of nesting gulls. Objective 2b and 3. We will calculate how far each duck and pheasant nest is to the nearest gull colony and power line.

Impacts
What was accomplished under these goals? Accomplishments Objective 1. We assessed raven, crow, magpie, hawk and eagle numbers at 1022 random points during 2014. Of the 53 duck nests that we located, all but 13 failed due to predators. Objective 2a. We located 31 islands in U.S. Bear River Migratory Bird Refuge that contained nesting colonies of California gulls. We also located five gull colonies on islands in the Great Salt Lake and two on Neponset Reservoir in Rich County. We counted all gull nests (43,000) in these colonies using ground counts and by taking aerial photos. Objective 2b and 3. We calculated distances of each duck nest to the nearest gull colony, power line. We used these data to determine nest densities. During 2014, duck nesting success and densities were unrelated to distances to gull colonies.

Publications

• Type: Book Chapters Status: Published Year Published: 2014 Citation: Conover, M. R., Dinkins, J. B., Haney, M. J. (2014). Impacts of weather and accidents on wildlife. Wildlife Management and Conservation (pp. 144-145.). Baltimore, Maryland: The Wildlife Society and John Hopkins University Press.
• Type: Journal Articles Status: Published Year Published: 2014 Citation: Dinkins, J., Conover, M. R., Kirol, C., Beck, J., Frey, N. (2014). Greater Sage-Grouse (Centrocercus urophasianus) hen survival: effects of raptors, anthropogenic and landscape features, and hen behavior. Canadian Journal of Zoology, 92, 319-331.
• Type: Journal Articles Status: Published Year Published: 2014 Citation: Dinkins, J., Conover, M. R., Kirol, C. P., Beck, J. L., Frey, N. (2014). Greater sage-grouse (Centrocercus urophasianus) select habitat based on avian predators, landscape composition, and anthropogenic features. To appear in Condor: Ornithological Applications.
• Type: Journal Articles Status: Published Year Published: 2014 Citation: Dinkins, J. B., Conover, M. R., Mabray, S. T. (2014). Do artificial nests stimulate nest success of great sage-grouse? Human-Wildlife Interactions, 7, 299-312.
• Type: Journal Articles Status: Published Year Published: 2014 Citation: Dinkins, J. B., Conover, M. R., Kirol, C. P., Beck, J. L., Frey, S. N. (2014). Greater sage-grouse hen survival: effects of raptors, anthropogenic and landscape features, and hen behavior. Condor, 116, 629-642.
• Type: Journal Articles Status: Published Year Published: 2014 Citation: Roberts, A. J., Conover, M. R. (2014). Diet and body mass of ducks in the presence of commercial harvest of brine shrimp cycts in the Great Salt Lake. Journal of Wildlife Management, 78, 1197-1205.
• Type: Journal Articles Status: Published Year Published: 2014 Citation: Roberts, A. J., Conover, M. R. (2014). Factors influencing mortality of eared grebes during a mass downing. Wilson Journal of Ornithology, 126, 584-591.
• Type: Journal Articles Status: Published Year Published: 2014 Citation: Roberts, A. J., Conover, M. R., Luft, J., Neil, J. (2014). Population fluctuations and distribution of staging eared grebes in North America. Canadian Journal of Zoology, 91, 906-913
• Type: Journal Articles Status: Published Year Published: 2014 Citation: Roberts, A. J., Conover, M. R. (2014). Role of benthic substrate in waterfowl distribution on Great Salt Lake. Waterbirds, 37, 298-306.

Progress 07/25/13 to 09/30/13

Outputs
Target Audience: Wyoming Animal Damage Management Board Wyoming Land Conservation Initiative U.S. Bureau of Land Management Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? I am recruiting a graduate student to work on this project. How have the results been disseminated to communities of interest? Presentations about this project have been given the Utah Chapter of the Wildlife Society, Wyoming Game and Fish, and U.S. Bureau of Land Management What do you plan to do during the next reporting period to accomplish the goals? Objective 1. I will return to the same random points to count avian predators in 2014. Objective 2a. I will resurvey all gull colonies located throughout Rich, Box Elder, and Davis counties. Objectives 1, 2, and 3. I will locate pheasant and ducks nests both near and away from gull colonies and power lines. I will revisit nests after the birds have finished incubating them to determine which ones were successful (i.e. one or more eggs hatched) or unsuccessful.

Impacts
What was accomplished under these goals? Accomplishments Objective 1. I assessed abundance of avian predators (magpies, ravens, hawks, eagles) at a series of random points. In the future, USDA Wildlife Services will initiate lethal control of ravens; my baseline numbers will allow me to assess if the control efforts are successful in reducing raven populations. Objective 2a. I located and surveyed gull colonies located throughout Rich, Box Elder, and Davis counties. Objectives 2b, 2c, and 3. This project started after the 2014 nesting season so I was unable to locate pheasant and ducks nests.

Publications