The Ecology of Wild Turkey Foraging in Pacific Northwest Ecosystems

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AN ABSTRACT OF THE THESIS OF

Sara Tondee Evans-Peters for the degree of Master of Science in Wildlife Sciences presented on September 13, 2013.

Title: The Ecology of Wild Turkey (Meleagris gallopavo) Foraging in Pacific Northwest Ecosystems

Abstract approved:

______

Bruce D. Dugger

Abstract

Wild turkeys (Meleagris gallopavo) were first successfully introduced into Oregon and

Washington in the 1960s; the population has grown in size and expanded in distribution to a point

where it provides an important recreational hunting opportunity in both states that generates

significant funds for habitat conservation and contributes financially to local economies. Wild

turkeys are not native to Oregon or Washington leading some to question if turkeys should be

actively managed as a game bird. While no detrimental effects of turkeys have been documented

in either state, there has been virtually no research on the biology and ecology of turkeys in

Oregon and Washington to contribute information that aids in managing the species and informing the debate about managing for the persistence of a non-native species. In this thesis, I quantify the diet of turkeys in Oregon and Washington and determine if wild turkeys are endozoochorously dispersing the seeds of plants they consume. Contributing information about the basic biology of turkeys could aid management and help contribute to a mechanistic understanding of how turkeys might help shape ecosystem structure and function. I characterized the diet of wild turkeys in Oregon and Washington by examining the crops of hunter harvested and collected turkeys (n = 536) during three time periods (fall-winter, spring and summer) from four geographic regions during 2009-2011. I compared diet composition among regions and

between seasons at both a broad categorical level (i.e., fruits, leaves, flowers, invertebrates and

underground plant parts) and at the level of individual taxa. Based on previous research, I

predicted that consumption of leaves, flowers, and invertebrates would be higher in spring and

consumption of fruits would be highest in fall in all regions, but specific taxa that comprised each

broad category of food would vary among regions. I detected 123 plant and 35 invertebrate taxa

in turkey crops. Consistent with my prediction, wild turkeys consumed significantly more fruits

in fall/winter and more leaves and flowers in the spring; contrary to my prediction, invertebrate

consumption was higher in fall-winter for three of the four regions. Grasses (Poaceae) were the

most common leafy material consumed in all regions during both fall-winter and spring and the

most common fruits consumed in all regions during both seasons except in one region, in spring,

where oak acorns (Quercus sp.) dominated the diet. Within the grass family, wheat (Triticum sp.)

was the most abundant seed in all regions in fall-winter and the most abundant seed in 2 regions

in spring while corn (Zea sp.) was the most abundant seed in the remaining regions in spring.

The only other plant families that comprised >5% of aggregate percent dry mass within regions

(all food categories combined) included Rosaceae, Pinaceae, Fagaceae and Asteraceae in fall-

winter and Fabaceae, Fagaceae, Asteraceae, Pinaceae, and Ranunculaceae in spring.

Grasshoppers (Acrididae) were the most abundant invertebrate taxa in fall-winter while snails

(Gastropoda) were the most abundant invertebrate in spring. Aggregate percent dry mass of food

items differed by season for each region and differed among regions when analyzed by season.

Within each region, numerous taxa were unique and indicative of season (range: 2-18) but fewer

taxa were indicative of region (range: 0-9) indicating there was more variation in diet between

seasons than among regions. To examine dispersal capabilities, we recovered seeds contained

within wild turkey feces (30 feces/sample, n = 50 samples) during the fall-winter between 2009 and 2011. Twenty-two taxa of seeds were found intact and 9 of those were viable (41%) based on tetrazolium testing. Viability ranged from 2-70%, Fabaceae sp. (pea family) had the highest

viability (70%) followed by Toxicodendron sp. (poison oak-ivy, 24.5%) and Symphoricarpos sp.

(snowberry, 11.6%); the viability of the remaining 6 taxa was below 10%. The majority of seed taxa present in wild turkey diet in Oregon and Washington were not represented in fecal samples indicating turkeys destroy the majority of taxa consumed during the digestive process. Though wild turkeys appear to be primarily a seed predator, I found they are successfully dispersing

14.5% of the seed taxa identified in the diet. Most taxa identified in the diet and fecal samples were identified to family and there are natives and non-native species within those families. My results do not conclusively document any direct or indirect impacts of turkeys on native plants or wildlife, but do provide a baseline for considering impacts and future information needs.

The Ecology of Wild Turkey (Meleagris gallopavo) Foraging in Pacific Northwest Ecosystems

Sara Tondee Evans-Peters

A THESIS

submitted to

Oregon State University

in partial fulfillment of the requirements for the degree of

Master of Science

Presented on September 13, 2013

Commencement June 2014

Master of Science thesis of Sara Tondee Evans-Peters presented on September 13, 2013.

APPROVED:

______

Major Professor, representing Wildlife Science

______

Head of the Department of Fisheries and Wildlife

______

Dean of the Graduate School

I understand that my thesis will become part of the permanent collection of Oregon State

University libraries. My signature below authorizes release of my thesis to any reader upon request.

______

Sara Tondee Evans-Peters, Author

ACKNOWLEDGMENTS

Though my name appears solely on the cover of this document, a great many people have contributed to its production. I owe my gratitude to the combined force of all those people that made this project possible and to them I credit my graduate experience; an incredible adventure that changed the trajectory of my life forever.

In the course of my fieldwork, data analysis and manuscript preparation, there are always a few people whose contributions make the work more robust and the endeavor more rewarding.

My deepest gratitude is to my advisor, Dr. Bruce Dugger. I have been amazingly fortunate to have an advisor who gave me the freedom to explore on my own and at the same time guidance to recover when I took steps in the wrong direction. Bruce taught me how to question assumptions and express ideas. His patience and encouragement helped me overcome many crisis situations and I will always look to him as mentor and friend. I also thank my committee members Dr. Clinton Epps and Dr. Richard Halse; Dr. Epps for his contributions to sample collections and Dr. Halse for his countless hours, patience and support with plant identification and botanical expertise. Numerous other faculty and staff within the Oregon State family helped me along the way, and I would especially thank Dr. Bruce McCune for statistical advice and Dr.

Darrell Ross for his assistance with invertebrate identification. Sample processing was a large component of this project and it took a small army of dedicated individuals to accomplish this task. I thank my technicians: Cameron King, Trevor Fox, Allison Field, Kerstin Beerweiler,

Tucker Doyle and Erin Harrington. I would especially like to thank Cameron King for his technical assistance with plant identification and for helping me work out the kinks of the project during its early stages. His dedication to the project and his independent critical thinking allowed me to focus on other tasks with little oversight.

The continued support of the Dugger Lab, past and present, has been instrumental in this project. Thank you to Lance Wyss, Blake Barbaree, Gary Ivey, Erin Harrington and Kevin

Buffington for their support and contributions in the course of my fieldwork, data analysis and thesis preparation and thank you Chris Malachowski for assisting with data analysis and thesis preparation. Lastly, I express utmost gratitude to Dr. Anne Mini not just for her unwavering academic, technical and emotional support but most importantly, her friendship.

Funding for my project was provided by Oregon Department of Fish and Wildlife,

Washington Department of Fish and Wildlife, the United States Forest Service and Department of

Fish and Wildlife at Oregon State University. I also thank Oregon Hunters Association, the

National Wild Turkey Federation, Ifish.net and Strand Outdoors for supporting project awareness and facilitating sample collections. I express gratitude to the many state district biologists and staff for their time, knowledge and assistance facilitating sample collection throughout this project including Dave Budeau, Mick Cope, Tom Lum, Steve Denney, Jeremy Thompson, Joey

McCanna, Nick Leonetti, Michael Moore, Richard Green, Vince Oredson, Brandon Reishus,

Mark Vargas, Sue VanLeuven and all the other state agency staff from across Oregon and

Washington that made this project possible. Additionally, I would like to thank Monty Gregg and

Bill Otani, U.S. Forest Service.

This project was a collaborative effort that relied on the hunters of Oregon and

Washington. I thank each and every sportsman and woman for the time and effort they spent to remove, store and submit crops for this project. This project would not have been successful without the assistance of each and every individual hunter. Additionally, many folks from local

OHA and NWTF chapters came together to get the word out and facilitate collection efforts. I would specifically like to thank Joe Ricker, Fred Walasavage and Bill Littlefield (OHA) and Kurt

Beckely and Ron Smallwood (NWTF).

Volunteers made this project possible and I would especially like to thank Dave Kruse and Larry Walker. Both Dave and Larry put in countless hours collecting, storing, packaging and delivering fecal samples and I would also like to thank their families for putting up with those

samples filling up the freezers throughout the fall and winter. Additionally, Dave and Larry supported the project by collecting and submitting crop samples for the diet study.

I dedicate this thesis to my niece, Avery Marie Giesler Paroulek; may you grow to become a strong, intelligent and gentle woman. I am indebted to my parents Ben and Suzanne

Paroulek, who provided me with unconditional encouragement and support though my educational career and, more importantly, throughout my life. Specifically, thank you to my mother for instilling me with a strong work ethic and goal oriented mentality and to my father for awarding me a sense of inquisitiveness and deep appreciation for all of nature’s wonders. I would also like to thank my brother, Matthew Paroulek, for technical ArcGIS support, editing skills and overall support through the times when I was physically away from the support system at OSU. As always, huge thanks to my girls, Maggie Staley and Shawna Giesler for their continued interest in my scientific endeavors and rambling.

Most importantly, I would like to thank my husband, Graham Evans-Peters, for turning a small academic adventure into a life-changing event. Your encouragement, assistance, love and support carried me through graduate school and made even the toughest times seem like small speed bumps.

CONTRIBUTION OF AUTHORS

Dr. Bruce Dugger assisted with all aspects of this study, therefore his input and recommendations are tremendously appreciated. Dr. Richard Halse assisted in plant identification and expertise in plant systematics.

TABLE OF CONTENTS

Page

1. INTRODUCTION …………………………………………...... 1

GENERAL INTRODUCTION …………………………………..……...... 1

STUDY AREA ………………………………….………………...... 4

LITERATURE CITED …………………………………………...... 8

2. REGIONAL AND SEASONAL VARIATION IN WILD TURKEY DIET COMPOSITION (Meleagris gallopavo) IN OREGON AND WASHINGTON…………... 11

INTRODUCTION ….……………………………………..………………….. 11

METHODS …..………………………………………….……………………. 13

Sample Collection and Processing……………………...... 13

Statistical Analysis……………………………………...... 15

RESULTS…...…………………………………………………………...... 16

Major Food Types……………………………………………………... 17

Taxonomic Composition of the Diet…….………………………..…… 17

DISCUSSION ………………………………………………………………… 39

Major Food Types……………………………………………………... 39

Taxonomic Composition of the Diet…………….………...………..…. 41

MANAGEMENT IMPLICATIONS …………………………………………. 44

LITERATURE CITED ………………………………………………..……… 47

3. SEED DISPERSAL BY WILD TURKEYS (Meleagris gallopavo) IN OREGON AND WASHINGTON ……………………………...………………………………………… 51

INTRODUCTION ……………………………………………………….…… 51

METHODS …………………………………………………………..……….. 53

TABLE OF CONTENTS (Continued)

Page

Sample Collection and Processing………………………………..….... 53

Statistical Analysis………………………….…………………………. 54

RESULTS …………………………………………………………..………… 56

DISCUSSION …………………………………………………………..…….. 62

MANAGEMENT IMPLICATIONS ……………………………………….… 65

LITERATURE CITED ………………………………………………..……… 67

4. SYNTHESIS: CONNECTING WILD TURKEY (Meleagris gallopavo) FORAGING AND SUBSEQUENT SEED DISPERSAL…………………………….…...... 71

LITERATURE CITED …………………………………...…………………... 75

5. COMPREHENSIVE LITERATURE CITED …………………………………………... 76

6. APPENDICES …………………………………………………………………………... 85

LIST OF FIGURES

Figure Page

Figure 1.1. Study regions for wild turkey crop and fecal collections during fall-winter, 7 spring and summer of 2009-2011 in Oregon and Washington……………………………..

Figure 3.1. Total number of viable seeds recovered from 1,500 wild turkey fecal samples in Oregon and Washington in the fall and winter of 2009-2010 and 2010-2011 in 4 regions. Number heading each column is the percent of seeds that were viable. NR = Northern Rockies-Plateau Region in northeast Washington; CF = Eastern Cascade Foothills Region in south-central Washington and north-central Oregon; BM = Blue Mountain-Plateau Region in northeast Oregon and southeast Washington and KM = 60 Klamath Mountain Region in southwestern Oregon……………………………………….

Figure 3.2. Relationship between seed mass (g) and seed viability for seeds recovered from 1,500 wild turkey fecal samples in Oregon and Washington in the fall and winter of 2009-2010 and 2010-2011 (Pearson’s correlation coefficients, r = 0.71, P = 0.03). If Fabaceae sp. is excluded from the analysis then percent viability is more correlated with 61 seed mass (r = 0.81, P = 0.01)……………………………………………………………...

Figure 3.3. Relationship between seed viability (%) and percent neutral detergent fiber (NDF) of seeds recovered from 1,500 wild turkey fecal samples in Oregon and Washington in the fall and winter of 2009-2010 and 2010-2011 (Pearson’s correlation 66 coefficients: r = 0.99, P < 0.001)…………………………………………………………...

LIST OF TABLES

Table Page

Table 2.1. Sample sizes of wild turkey crops collected in Oregon and Washington between 2009 and 2011 during 3 seasons (fall-winter: 22 September through March 19, spring: 20 March through 19 June and summer: 20 June through September 21) summarized by region* and collection year. Summer collection only occurred in the KM 21 region……………………………………………………………………………………….

Table 2.2. Mean aggregate percent dry mass of foods consumed by wild turkeys (mean ± SE) in Oregon and Washington between 2009 and 2011 during 2 seasons (fall-winter: 22 22 September through March 19 and spring: 20 March through 19 June) in 4 regions*……...

Table 2.3. Mean aggregate percent dry mass of foods consumed in the fall and winter (22 September through March 19) by wild turkeys (mean ± SE) in Oregon and Washington by region* between 2009 and 2011 (n = 221). Only foods that comprised greater than 1% of the overall mean are included. Foods less than 0.1% are listed as trace “tr”. 23 ………………………………………………………………………………………...

Table 2.4. Mean aggregate percent dry mass of foods consumed in spring (20 March through 19 June) by wild turkeys (mean ± SE) in Oregon and Washington by region* between 2009 and 2011 (n = 239). Only foods that comprised greater than 1% of the 25 overall mean are included.…...……………………………………………………………..

Table 2.5. Percent occurrence of foods consumed in the fall and winter (22 September through March 19) by wild turkeys in Oregon and Washington by region* between 2009 27 and 2011 (n = 221). Only foods that occurred in over 1% of the all samples are included.

Table 2.6. Percent occurrence of foods consumed in spring (20 March through 19 June) by wild turkeys (mean ± SE) in Oregon and Washington by region* between 2009 and 30 2011 (n = 239). Only foods that occurred in over 1% of the all samples are included……

Table 2.7. Foods consumed by wild turkeys indicative of 4 regions* in Oregon and Washington between 2009 and 2011 within 2 seasons (fall-winter: 22 September through March 19 and spring: 20 March through 19 June). Taxa displayed had observed indicator 32 values (IV) with p-values <0.05……………………………………………………………

Table 2.8. Foods consumed by wild turkeys indicative of 3 seasons (fall-winter: 22 September through March 19, spring: 20 March through 19 June and summer: 20 June through September 21) within 4 regions* in Oregon and Washington between 2009 and 33 2011. Taxa displayed had observed indicator values (IV) with p-values <0.05.………….

LIST OF TABLES (Continued)

Table Page

Table 2.9. Mean aggregate percent dry mass of foods consumed by wild turkeys (mean ± SE) in the Northern Rockies-Plateau (NR) region, northern Washington (Pend Oreille, Stevens, Ferry, Lincoln and Spokane Counties) during the fall-winter (22 September through March 19) and spring (20 March through 19 June) between 2009 and 2011 (n = 35 135 crops). Only foods that comprised greater than 1% of the annual mean are included..

Table 2.10. Mean aggregate percent dry mass of foods consumed by wild turkeys (mean ± SE) in the Eastern Cascade Foothills (CF) region, south-central Washington (Skamania and Klickitat Counties) and north-central Oregon (Hood River, Wasco, Sherman and Gilliam Counties), during the fall-winter (22 September through March 19) and spring (20 March through 19 June) between 2009 and 2011 (n = 61 crops). Only foods that 36 comprised greater than 1% of the annual mean are included…………………......

Table 2.11. Mean aggregate percent dry mass of foods consumed by wild turkeys (mean ± SE) in the Blue Mountains-Plateau (BM) region, northeast Oregon (Morrow, Umatilla, Union, Wallowa, Grant and Baker Counties) and southeast Washington (Walla Walla, Columbia, Garfield, and Asotin Counties), during the fall-winter (22 September through March 19) and spring (20 March through 19 June) between 2009 and 2011 (n = 114 37 crops). Only foods that comprised greater than 1% of the annual mean are included…….

Table 2.12. Mean aggregate percent dry mass of foods consumed by wild turkeys (mean ± SE) in the Klamath Mountains (KM) region, southwestern Oregon (Douglas, Jackson, Josephine, and Coos Counties) during the fall-winter (22 September through March 19), spring (20 March through 19 June) and summer (20 June through September 21) between 2009 and 2011 (n = 180 crops). Only foods that comprised greater than 1% of the annual 38 mean are included.…...………………………………………………………………..……

Table 3.1. Percent occurrence of seed recovered from wild turkey fecal samples collected at 50 sites, in 4 regions* throughout Oregon and Washington in the fall and winter of 2009-2010 and 2010-2011 (22 September through March 19). Percent 58 occurrence was calculated as the percentage of samples that contained each taxa......

Table 3.2. Viability of seeds recovered from wild turkey fecal samples collected in Oregon and Washington in the fall and winter (22 September through March 19) of 59 2009-2010 and 2010-2011. Tetrazolium (TZ) testing was used to estimate viability……..

LIST OF APPENDICES

Appendix Page

Appendix I. Wild turkey crop and esophagus removal and submittal procedure for crops 86 collected from Oregon Department of Fish and Wildlife and Washington Department of Fish and Wildlife staff and for advertisement purposes…………………………………….

Appendix II. Mean aggregate percent dry mass of foods consumed by wild turkeys (mean ± SE) in Northeast Washington (Pend Oreille, Stevens, Ferry, Lincoln and Spokane Counties) during the fall-winter (22 September through March 19) and spring (20 March through 19 June) between 2009 and 2011. Foods less than 0.1% are listed as trace 87 “tr”…………………………………………………………………………………………...

Appendix III. Mean aggregate percent dry mass of foods consumed by wild turkeys (mean ± SE) in the Blue Mountains-Plateau region (BM) south-central Washington (Skamania and Klickitat Counties) and north-central Oregon (Hood River, Wasco, Sherman and Gilliam Counties), during the fall-winter (22 September through March 19) and spring (20 March through 19 June) between 2009 and 2011. Foods less than 0.1% are 91 listed as trace “tr”......

Appendix IV. Mean aggregate percent dry mass of foods consumed by wild turkeys (mean ± SE) in northeast Oregon (Morrow, Umatilla, Union, Wallowa, Grant and Baker Counties) and southeast Washington (Walla Walla, Columbia, Garfield, and Asotin Counties), during the fall-winter (22 September through March 19) and spring (20 March through 19 June) between 2009 and 2011. Foods less than 0.1% are listed as trace 94 “tr”…………………………………………………………………………………………...

Appendix V. Mean aggregate percent dry mass of foods consumed by wild turkeys (mean ± SE) in southwestern Oregon (Douglas, Jackson, Josephine, and Coos Counties) during the fall-winter (22 September through March 19) and spring (20 March through 19 June) between 2009 and 2011. Foods less than 0.1% are listed as trace 98 “tr”…………………………………………………………………………………………...

Appendix VI. Native Oregon and Washington plants that provide forage for wild turkeys as determined by this study and past wild turkey diet studies (reviewed in Schemnitz 1956, Schorger 1966, Korschgen 1967, Eaton 1992, Hurst 1992). Location provides guidance for recommended planting; east of Cascade Mountains (E) versus west 103 (W)…………………………………………………………………………………………..

Appendix VII. Foods consumed by wild turkeys in Oregon and Washington between 2009 and 104 2011………………………………………………………………………………………….

Appendix VIII. Sampling protocol for collection, storage, and shipment of wild turkey 109 (Meleagris gallopavo) fecal samples………………………………………......

THE ECOLOGY OF WILD TURKEY (Meleagris gallopavo) FORAGING IN PACIFIC NORTHWEST ECOSYSTEMS

Chapter 1

GENERAL INTRODUCTION

Wild turkeys (Meleagris gallopavo, hereafter turkeys) are endemic to North America, and are an important game bird species whose population and distribution have undergone significant changes since Europeans settled the continent. Turkeys historically occurred in 39 states (Kennamer et al. 1992), but unregulated harvest and deforestation caused declines in turkey populations and by 1920 turkeys were eliminated from 18 of the original 39 states. During the early 1950’s regulated harvest and transplanting efforts resulted in the reestablishment of turkeys to their historic range and expansion into many states that did not originally support turkeys including Oregon and Washington (Leopold 1944, Aldrich and Duvall 1955, Kennamer et al.

1992). Today there is estimated to be over 7 million wild turkeys in North America that occur in

all U.S. states, except Alaska, southern Canada and central Mexico (Eaton 1992).

The use of intensive management practices, including active trap and translocation

programs, helped turkeys increase and spread throughout Oregon and Washington (ODFW 2004,

WDFW 2005a). Though many attempts were made to introduce turkeys to the Pacific Northwest

beginning in the late 1800’s, the first successful introduction occurred in 1960 and 1961

(Kennamer et al. 1992). At several sites east of the Cascades, 114 wild trapped Merriam’s

turkeys from New Mexico, Arizona and Colorado were released in Oregon and Washington

resulting in a naturally reproducing population (ODFW 2004, WDFW 2005a, Kennamer et al.

1992). Continued introductions and population supplementation over the next 30 years helped

turkeys reach present population levels. Currently, three subspecies of wild turkey occur in

Oregon and Washington: Rio Grande (M.g. intermedia), Merriam’s (M.g. merriami) and Eastern

(M.g. silvestris), and hybridization frequently occurs east of the Cascades between the Merriam’s

and Rio Grande subspecies (ODFW 2004, WDFW 2005a). Today, turkeys occur in 35 of 36 2

counties in Oregon and 30 of 39 counties in Washington (ODFW 2004, WDFW 2005a). No current population estimates are available for Oregon or Washington but data from harvest reports suggest populations are increasing (ODFW 2004, 2011; WDFW 2005a, 2011). As turkey populations increased so did hunting opportunities; consequently, both states have active turkey management programs (ODFW 2004, WDFW 2005a).

Management of turkey populations in the Pacific Northwest provides significant recreational opportunities for hunters, generates additional revenue for habitat management, and provides economic benefit for Oregon and Washington communities. The first official fall hunting season in Washington and Oregon occurred in 1965; Oregon opened a spring hunt the following year and Washington followed suit in 1970. Spring turkey hunters in Washington spent a total of $9,394,000 in 2003 generating $495,000 in state tax revenue and $493,000 in turkey license and tag sales (Southwick Associates 2003). In 2011, 14,675 people hunted turkey in the fall in Washington supporting state wildlife programs and local economies. Consequently, as public interest and hunting opportunities have increased, the interest in turkey population and habitat management has increased.

Despite their benefits to recreational hunters and local communities, turkeys are not native to Oregon or Washington; thus, some have questioned the value of maintaining turkey populations in either state. No detrimental biological effects of turkeys have been documented since the establishment of turkeys in Oregon and Washington, but no research has looked for possible impacts. While many non-native species do not have obvious detrimental environmental effects or may even facilitate facultative relationships with native species (Rodriguez 2006,

Foster and Robinson 2007, NISC 2008, Davis et al. 2011), reducing the abundance and distribution of non-native species in the Pacific Northwest, the U.S. and worldwide is a major conservation objective because nonnative species can cause interactions that cascade through ecosystems with negative consequences (NISC 2008, Clavero et al. 2009, Mac Nally et al. 2012, 3

Simberloff et al. 2012). Understanding how wild turkeys fit into northwest ecosystems is the first

step to understanding their role in shaping ecosystem structure and function.

One way turkeys can influence ecosystem structure and function is through their foraging

behavior. Foraging may have an impact via three principle mechanisms. First, turkeys might

compete with native species for food sources or may impact plant and animal populations through

direct predation. Wild turkey diet has been extensively researched across the U.S. but in over 170

studies reviewed (reviewed in Schemnitz 1956, Schorger 1966, Korschgen 1967, Eaton 1992,

Hurst 1992), only two occurred in Oregon or Washington and they lacked the scope needed to

draw strong inferences (Mackey 1981, Wengert et al. 2009). Second, turkeys may disperse the

seeds of native or exotic plants through their droppings, which may cause landscape level

changes in plant population and community dynamics (Howe and Miriti 2004). Wild turkeys

consume many of the same fruits and seeds as other established avian dispersers (Krefting and

Roe 1949, Mueller and van der Valk 2002, Wongsriphuek et al. 2008, Brochet et al. 2010), but very little research has looked at wild turkeys as a potential dispersal vector (Wald et al. 2005).

Third, turkey foraging behavior such as scratching can influence local habitat conditions that may affect subsequent germination and growth of plants (Moore and Wein 1977, Rinkes and

McCarthy 2007). Turkeys often scratch the ground to uncover food, which removes leaf litter that may inhibit seedling recruitment by altering local soil conditions (Rinkes and McCarthy

2007).

My thesis research explores the role wild turkeys play in Oregon and Washington. In

Chapter 2, I quantify the diet and compare diet composition of turkeys among four regions in

Oregon and Washington. In Chapter 3, I determine if wild turkeys are endozoochorously dispersing plant seeds by identifying and testing the viability of seeds recovered from turkey fecal matter. Chapter 4 synthesizes information from Chapters 2 and 3 to better understand the role of wild turkeys in Pacific Northwest ecosystems by linking consumption and dispersal of native and nonnative taxa. 4

STUDY AREA

My study was conducted within four distinct regions in Oregon and Washington that all contain

high density turkey populations (Fig. 1; ODFW 2004, 2011; WDFW 2005a, 2011). Within those

ecoregions, I targeted game management units that had high hunter effort and success in order to

maximize sampling efficiency. Each region was representative of different Level III Ecoregions

as classified by the Environmental Protection Agency (EPA; Omemik 1987).

Northern Rockies-Plateau Region (NR) region is located in Northeast Washington and includes Pend Oreille, Stevens, Ferry, Lincoln and Spokane Counties. According to harvest trend data from 1991 to 2010 the turkey population has increased in all counties in the region, most prominently in Steven County (WDFW 2005a, WDFW 2011). The NR region includes the northern portion of the Columbia Plateau, mostly consisting of Channeled Scabland and Loess

Islands Level IV Ecoregions, and a large portion of the Canadian Rocky Mountains Ecoregion

(Omernik 1987). The Canadian Rocky Mountain Ecoregion in Washington is made up primarily of the Selkirk Mountains and is dominated by grasslands, dense coniferous forests and riparian woodlands. Low elevation forests are comprised mostly of ponderosa pine (Pinus Ponderosa),

Douglas-fir (Pseudotsuga menziesii), western red cedar (Thuja plicata) and hemlock (Tsuga sp.) with an understory dominated by devils club (Oplopanax horridus) and lady fern (Athyrium sp.;

Omemik 1987, NRCS 2012).

The Eastern Cascade Foothills (CF) region includes south-central Washington (Skamania and Klickitat Counties) and north-central Oregon (Hood River, Wasco, Sherman and Gilliam

Counties). This region contains large tracks of Oregon white oak woodlands, a priority habitat listed by WDFW (WDFW 2005b). The CF region encompasses the Cascades, the Eastern

Cascades Slopes and Foothills and the Columbia Plateau Ecoregions (Omemik 1987). The northern portion of the Eastern Cascades Slopes and Foothills supports open woodlands of ponderosa pine (Pinus ponderosa) and Douglas-fir forests interspersed with Oregon white oak 5

(Quercus garryana). The understory is dominated by bluebunch wheatgrass (Pseudoroegneria spicata), Idaho fescue (Festuca idahoensis), bitterbrush (Purshia tidentata), Oregon grape

(Mahonia aquifolium) and snowberry (Symphoricarpos sp.; Omemik 1987, NRCS2012). The

Columbia Plateau Ecoregion contains the upland of the plateau and the Columbia River Basin watershed system. It is characterized as a shrub-steppe habitat consisting of arid sagebrush steppe and open grasslands (Omemik 1987). Sagebrush and bunchgrass association are prominent and dominant plants include bluebunch wheatgrass, Idaho fescue, Wyoming big sagebrush (Artemisia tridentata subsp. wyomingensis), basin big sagebrush (Artemisia tridentata subsp. tridentata) and sandberg bluegrass (Poa secunda). Nonnative cheatgrass (Bromus tectorum) covers much of the landscape (Omemik 1987, NRCS 2012). Large riverine systems including the Klickitat, White Salmon, Hood River and Deschutes feed the Columbia creating numerous riparian corridors dominated by dwarf hardwoods. A large portion of the region is in private grazing and farming with major crops consisting of fruit trees, vineyards, winter wheat, alfalfa and barley (NRCS 2006).

The Blue Mountains-Plateau (BM) region includes northeast Oregon (Morrow, Umatilla,

Union, Wallowa, Grant and Baker Counties) and southeast Washington (Walla Walla, Columbia,

Garfield, and Asotin Counties). The BM region borders the CF region to the west and is also a part of the Columbia Plateau Ecoregion. In the west the region is dominated by shrub steppe grasslands and big sage brush with bluebunch wheatgrass and Idaho fescue grasslands (Omemik

1987). Major agricultural crops include wheat, barley, alfalfa, hay, lentils and vineyards (NRCS

2006). In the eastern section of the region is the Blue Mountain Ecoregion. The Strawberry and

Blue Mountains along with the Snake River and Hells Canyon create diverse habitat types comprised of mixed coniferous forests, dominated by ponderosa pine and Douglas-fir with an understory dominated by snowberry at the lower elevations. The Blue Mountain Ecoregion is characterized by grasslands that support bluebunch wheatgrass, pinegrass (Calamagrostis rubescens), bluegrass (Poa sp.), Idaho fescue, basin wildrye (Elymus sp.), juniper (Juniperus sp.) 6

and numerous species of sagebrush. Forests are dominated by ponderosa pine, western larch

(Larix occidentalis) and Douglas-fir. Riparian corridors often support snowberry, black cottonwoods (Populus trichocarpa), Himalayan blackberry (Rubus armeniacus), black hawthorn

(Crataegus douglasii), alder (Alnus sp.), western chokecherry (Prunus virginiana), willow (Salix sp.), serviceberry (Amelanchier sp.) and thimbleberry (Rubus parviflorus; Omemik 1987, NRCS

2012).

The Klamath Mountains (KM) region is located in southwestern Oregon (Douglas,

Jackson, Josephine, and Coos Counties) and covers a variety of habitat types ranging from the

Pacific Coast to the Cascade Mountains. Ecoregions include the Coast Range to the west, the

Klamath Mountains/California High North Coast though the center, and the Cascades Ecoregions.

The Siskiyou-Trinity range runs from the center of Douglas County, through Jackson County and into northern California and is dominated by Douglas fir, ponderosa pine, sugar pine (Pinus lambertiana), incense cedar (Calocedrus decurreus), white fir (Abies concolor) and Pacific madrone (Arbutus menziesii). Poison oak (Toxicodendron diversilobum), snowberry, Oregon grape, manzanita (Arctostaphylos sp.), Ceanothus sp. and rose (Rosa sp.) characterize the understory. Oak woodlands consisting of Oregon white oak, California black oak (Quercus kelloggii) and canyon live oak (Quercus chrysolepis) are interspersed throughout the region along with grasslands supporting mostly fescues (Festuca sp.), bluegrasses, bromes (Bromus sp.) and wild oats (Avena fatua; Omemik 1987, NRCS 2012). Land uses include mostly timber production, grazing and agriculture dominated by fruit crops, irrigated pasture and grain (NRCS

2006).

Northern Rockies Plateau (NR)

Eastern Cascade Foothills (EC)

Klamath Mountains Blue Mountains (KM) Plateau (BM)

Figure 1.1 Study regions for wild turkey crop and fecal collections during fall-winter, spring and summer of 2009-2011 in Oregon and Washington.

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Foster, J. T., and S. K. Robinson. 2007. Introduced birds and the fate of Hawaiian rainforests. Conservation Biology 21:1248-1257.

Howe, H. F., and M. N. Miriti. 2004. When seed dispersal matters. Bioscience 54:651-660.

Hurst G. A. 1992. Foods and Feeding. Pages 66-83 in J. G. Dickson, editor. The Wild Turkey Biology and Management. Stackpole Books, Mechanicsburg, Pennsylvania, USA.

Kennamer, J. E., M. Kennamer, and R. Brenneman. 1992. History. Pages 6-17 in J. G. Dickson, editor. The Wild Turkey Biology and Management. Stackpole Books, Mechanicsburg, Pennsylvania, USA.

Korchgen, L. J. 1967. Feeding habits and food. Pages 137-198 in O. H. Hewitt, editor. The Wild Turkey and its Management. The Wildlife Society, Washington, D.C., USA.

Krefting, L. W., and E. I. Roe. 1949. The role of some birds and mammals in seed germination. Ecological Monographs 19:269-286.

Leopold, A. S. 1944. The nature of heritable wildness in turkeys. Condor 46:133-197.

MacNally, R., M. Bowen, A. Howes, C. A. McAlpine, and M. Maron. 2012. Despotic, high- impact species and the subcontinental scale control of avian assemblage structure. Ecology 93:668-678.

Mackey, D. L. 1981. Habitat use by broods of Merriam’s turkeys in south-central Washington. Thesis, Washington State University, Pullman, Washington, USA.

Moore , J. M., and R. W. Wein 1977. Viable seed populations by soil depth and potential site recolonization after disturbance. Canadian Journal of Botany 55:2412-2408.

Mueller, M. H., and A. G. van der Valk. 2002. The potential role of ducks in wetland seed dispersal. Wetlands 22:270-278. 9

Natural Resources Conservation Service [NRCS]. 2006. Major land resource area explorer. http://www.cei.psu.edu/mlra/. Accessed 10 June 2012.

Natural Resources Conservation Service [NRCS]. 2012. PLANTS Database. http://plants.usda.gov/java/.http:/. Accessed 20 August 2012.

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Omernik, J. M. 2004. Perspectives on the nature and definition of ecological regions. Environmental Management 34(Supplement 1):S27-S38.

Oregon Department of Fish and Wildlife [ODFW]. 2004. Wild Turkey Management Plan. Oregon Department of Fish and Wildlife, Salem, Oregon, USA.

Oregon Department of Fish and Wildlife [ODFW]. 2005. Oregon Invasive Species Action Plan. Oregon Department of Fish and Wildlife, Salem, Oregon, USA.

Oregon Department of Fish and Wildlife [ODFW]. 2006. Oregon Conservation Strategy. Oregon Department of Fish and Wildlife, Salem, Oregon, USA.

Oregon Department of Fish and Wildlife [ODFW]. 2011. Oregon Upland Game Bird Harvest 1993-2011. Upland Game Division. http://www.dfw.state.or.us/resources/hunting/upland_bird/harvest/docs/1993- 2011_upland_harvest.pdf. Accessed 10 June 2011.

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Schemnitz, S. D. 1956. Wild turkey food habits in Florida. Journal of Wildlife Management 20:132-137.

Schorger, A. W. 1966. The wild turkey: its history and domestication. University of Oklahoma Press, Norman, Oklahoma, USA.

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Southwick Associates. 2003. The 2003 Economic Contributions of Spring Turkey Hunting. Fernandina, Florida, Prepared for National Wild Turkey Federation, Edgefield South Carolina, USA.

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REGIONAL AND SEASONAL VARIATION IN WILD TURKEY (Meleagris gallopavo) DIET

COMPOSITION IN OREGON AND WASHINGTON

Chapter 2

DIET COMPOSITION

Wild turkeys (Meleagris gallopavo) occur throughout much of the United States, including areas outside their historic range, and are a target species for management in most states (Wunz 1992).

Turkeys were introduced to the Pacific Northwest in the late 1800’s and by 1960 naturally reproducing populations became established east of the Cascade Mountain range in both Oregon and Washington (ODFW 2004, WDFW 2005a). Throughout the next three decades active introduction and transplant programs, as well as natural immigration from Idaho, increased the density and distribution of turkey populations across both states (ODFW 2004, WDFW 2005a).

Turkeys provide significant recreational opportunities for hunters, generate additional revenue for habitat management, and provide economic benefit for Oregon and Washington communities

(Southwick Associates 2003). As public interest and hunting opportunities increase, there is a growing desire for enhanced turkey population and habitat management. Understanding baseline information on how wild turkeys fit into Pacific Northwest ecosystems is central to making informed management decisions.

Wild turkey food habits have been extensively researched across much of the contiguous

United States but there is a lack of data from the Pacific Northwest (reviewed in Schemnitz 1956,

Schorger 1966, Korschgen 1967, Eaton 1992, Hurst 1992). In over 170 wild turkey diet studies reviewed, only two occurred in Oregon or Washington (Mackey 1981, Wengert et al. 2009).

Mackey (1981) collected 35 wild turkey crops from Klickitat County, WA. Though useful, the sample size and geographic coverage was small. Wengert et al. (2009) opportunistically collected 435 fecal samples from a more diverse geographic area in central Oregon but there was no accounting for interdependence of samples, and the microhistological analysis used to identify 12

diet items under estimates soft, easily digestible foods (Holechek 1982, Rumble and Anderson

1996, Litvaitis 2000).

Recently, because of an increased concern regarding the impact of non-native species, questions have been raised about the possible ecological impacts of wild turkey foraging on native plant, insect, reptile and amphibian populations. Many of the sensitive, threatened and endangered plants and invertebrates listed in Oregon and Washington (WDFW 2005a, ODFW

2006, NRCS 2012) include species that are similar to taxa found in the diet of turkeys outside the

Pacific Northwest (reviewed in Schemnitz 1956, Schorger 1966, Korschgen 1967, Eaton 1992,

Hurst 1992). Turkeys are known as generalist foragers that consume an array of plant and animal

matter that is representative of annually, seasonally and regionally abundant foods.

Wild turkey diet varies seasonally due to changes in availability of food items and

variation in the nutritional requirements of turkeys throughout their annual cycle (Hengal 1990,

York and Schemnitz 2003, Restani et al. 2009, Stearns 2010). Wild turkey diet can be broken

into 5 major food categories that include fruits and seeds (reproductive plant bodies and the ovary

that encloses them), leaf material, simple flowers and flower heads, underground vegetative

structures (roots, bulbs and tubers) and animals (invertebrates and vertebrates). Coinciding with

seasonal availability, wild turkeys consume more leaf material in the spring and summer and

more fruits and seeds in the fall and winter (reviewed in Schemnitz 1956, Schorger 1966,

Korschgen 1967, Eaton 1992, Hurst 1992). Invertebrate consumption has also been shown to

increase in the spring, corresponding to increased availability and potentially related to the high

protein requirements of females during the breeding period. While these patterns are useful for

developing general predictions about turkey diets in the Pacific Northwest they do not provide

specific information on diet composition of wild turkeys in the Oregon and Washington.

In this chapter, I quantify the diet of wild turkeys in the Pacific Northwest to answer the

following questions regarding diet composition. First, does aggregate percent dry mass of food

types (fruits, leaf, flower, invertebrates and underground plant parts) vary between seasons (fall- 13

winter vs. spring)? I predicted that based on turkey diet elsewhere in the US, their diet in Oregon and Washington would be dominated by green leaf material, flower heads and invertebrates in the spring and fruits in the fall and winter and that those patterns would be similar among regions within the states. Second, how does the composition of the specific foods in the diet vary among regions and seasons? I expected to see differences among regions in which specific foods were dominant or unique in the major diet categories reflecting regional and seasonal availability and abundance.

METHODS

Sample Collection and Processing

I characterized the diet of turkeys by examining the crops of harvested and collected turkeys during three time periods; fall-winter (2009-10 and 2010-11), spring (2009, 2010 and 2011) and summer (2010 and 2011) from four regions: the Northern Rockies-Plateau (NR), the Blue

Mountains-Plateau (BM), the Eastern Cascade Foothills (CF) and the Klamath Mountains

(KM; Fig. 1.1). The seasons correspond with general patterns of food abundance in the environment and the annual cycle of the turkey. The fall-winter period (22 September through

March 19) corresponds with flocking behavior by non-breeding turkeys and could be a period of resource limitation increasing the likelihood of competition with other wildlife species. Spring

(20 March through 19 June) coincides with the onset of breeding, a period when females require increased protein and calcium consumption to facilitate egg formation (Gill 2007). Summer (20

June through September 21) is a period of high dietary protein requirement by poults and is a season underrepresented in turkey foraging literature (reviewed in Schemnitz 1956, Schorger

1966, Korschgen 1967, Eaton 1992, Hurst 1992).

I solicited hunter harvested crops by contacting individual hunters though targeted mailings, personal contact, web advertisement and hunting and conservation organizations. I distributed an information packet to a sample of fall and spring hunters in both states that 14

included a project overview and instructions on crop removal and submittal (Appendix I). Digital

links were also made available to promote project awareness. In Oregon, all fall turkey tag

permit holders were contacted prior to the start of the hunting season. No mailing occurred in the

spring because there was no mandatory reporting for turkey harvest therefore targeting a specific

group of hunters was not feasible. In Washington, hunters were contacted if they possessed a fall

turkey tag permit within a study area and had successfully harvested a turkey in both the two

previous years. Washington hunters were solicited through e-mail contact and received a digital

information packet similar to the Oregon mailing. I also distributed crop collection and removal

information to Oregon Department of Fish and Wildlife (ODFW) and Washington Department of

Fish and Wildlife (WDFW) staff. Additionally, the National Wild Turkey Federation (NWTF)

and the Oregon Hunters Association (OHA) promoted project awareness at state and local chapter

meetings. The project was also advertised on Ifish, a hunting and fishing web forum. Crops were

removed, labeled, frozen, and submitted to regional and state offices. All samples were then

mailed or transported to the ODFW’s Wildlife Population Lab located at the South Willamette

Watershed district office in Adair, Oregon.

With the assistance of state agency staff, we also collected turkeys using shotguns and

rifles to supplement hunter crop donations. Fall-winter collection occurred mainly outside

designated hunting seasons. State hunting regulations in Oregon and Washington only allow for

take of male turkey in the spring, therefore, collecting activities in spring targeted females to

supplement the sample of male crops submitted by hunters. Summer collections were restricted

to the KM Region. To increase the likelihood of obtaining birds with full crops, turkeys were

collected in the evening before they returned to roost sites or while birds were actively foraging.

Sex of birds collected was determined using plumage patterns (Lewis 1967) and age was

determined by general primary molt patterns (retention, shape, and barring of the 10th primary;

Healy and Nenno 1980). In the field, I removed crops and transported samples on ice to prevent further fermentation of contents. 15

In the lab, I thawed samples to room temperature and used a scalpel to make an incision in the crop and esophagus to remove contents for processing. I suspended samples in water baths to remove soft material. Then I washed samples through a series of mesh sieves (2mm, 500µm, and 350µm) and resuspended the retained material in water baths to separate all remaining items.

I identified all animals and plant material to order, family, genus or species level. Samples were labeled, dried to constant mass at 60°C and weighed to the nearest 0.0001 g. Crops that contained less than 0.25g total dry mass were considered empty and removed from analyses.

Statistical Analysis

I first calculated frequency of occurrence for each food in the diet as the percentage of all crops that contained a food, regardless of mass. The unit for statistical analyses was aggregate percent dry mass, which was calculated as the food item mass (g) divided by the total mass of the food items within a single crop. Mean aggregate percent dry mass was calculated as food item mass averaged across all birds. An arcsine square root transformation was used to reduce skewness and influence of dominant species, improve homogeneity of variance and create a normal distribution of food type proportions (McCune and Grace 2002, Ramsey and Schafer 2002).

Means and standard errors of non-transformed data are reported to make results easier to interpret

(Vest and Conover 2011).

I used a MANOVA to test my prediction that major diet composition would vary between seasons but not necessarily regions. For that analysis, food items were grouped in five broad categories: fruit (true seeds, achenes, true berries, drupes, pomes, accessory and aggregate fruits), leaf (broadleaf, conifer, succulent, true grasses, sedge, rush leaves but excludes bulb scales), flower (simple flowers, inflorescences and composite flower heads), underground plant part (roots, tubers and bulbs), invertebrates and miscellaneous. Miscellaneous (misc.) includes all other leftover food materials that were either too small for identification or did not fit into the categories previously listed (i.e., animal feed and human foods). I used individual turkey crops as sample units to determine the relationship between dependent variables (proportion of fruits, 16

leaf, flowers, underground plant parts and invertebrates) and explanatory variables (region,

season and year and their two-way interactions). Wilks’ lambda test criterion was used to

simultaneously evaluate the effects of explanatory variables on diet composition (Ramsey and

Schafer 2002). If the MANOVA indicated significant effects of explanatory variables (P <

0.05), univariate analysis of variance (ANOVA) was used to compare how aggregate percent dry

mass of food type varied with the explanatory variables (Ramsey and Schafer 2002).

A community analysis was conducted to compare seasonal differences in diet

composition within each region and regional differences in diet composition within each season.

I used multi-response permutation procedures (MRPP; Mielke 1984) in PC-ORD (v. 6.0;

McCune and Mefford 2011) with Sørenson distance measure to test the null hypothesis of no

difference in diet composition between season and region. Incorporating all food items in the

diet into statistical tests, such as MRPP, provides a finer resolution to understanding differences

and similarities in wild turkey diet. MRPP provides both a test statistic based on distribution

assumptions (i.e., a p-value) and a measure of the effect size. The effect size, denoted by an A-

value, describes the within-group homogeneity and ranges from 0 to 1, with 0 being that all items in the group are identical. In community ecology, it is common for the A-value to be below 0.1 and still be statically significant, while an A-value of 0.3 is considered high and denotes very distinct groupings. All unknowns within each food category were combined. Finally, I conducted indicator species analyses (ISA; Dufrêne and Legendre 1997) to identify taxa that were characteristic of a group when MRPP tests indicated a difference in diet composition. I report significant indicator values (IV; P ≥ 0.05).

RESULTS

I collected 536 crops from wild turkeys between the spring of 2009 and the summer of 2011; 33 were not processed due to decomposition, 28 were empty, and 13 were from outside the designated study regions, which left 462 crops available for analysis (Table 2.1). A total of 158 17

foods were detected in crops: 123 plant and 35 invertebrate taxa, 104 from the fall-winter season,

100 from spring and 39 from summer. Additionally, of 123 plant taxa, turkeys consumed more

than 1 structural part of 25 taxa (e.g., ranunculus leaf, seed and flower). Mean taxa richness per

crop was 6.5 ± 0.18, varying from 7.1 ± 0.27 in fall-winter to 6.0 ± 0.75 in spring and 5.41 ± 0.36

in summer). Mean alpha diversity was not significantly different between seasons (F2,428 = 2.55,

P = 0.11) or among regions (F3,428 = 2.41, P = 0.07).

Major Food Types

Overall, fruits constituted 54.7% of the aggregate percent dry mass in the diet followed by leaf

(26.0%), flower (5.8%), invertebrates (5.5%) and underground plant parts (1.9%). The combination of fruits, leaf, and flowers comprised greater than 82% of the aggregate percent dry mass diet for all regions in both seasons (Table 2.2). The composition of major food types in the

turkey diet included a significant season and region interaction (MANOVA, Wilks' λ = 0.93,

F18,1185 = 3.56, P = 0.03). For all regions, the biomass of fruits in the diet was greater in fall-

winter than spring (ANOVA, F1,424 = 52.9, P < 0.001) and the biomass of flowers (F1,424 = 16.4, P

< 0.001) and leaf (F1,424 = 35.2, P < 0.001) was greatest in spring (Table 2.2). Turkeys consumed

more invertebrates in the spring in the NR region but more in the fall-winter in all other regions

(ANOVA, invertebrates, F3,424 = 3.1, P = 0.02). The biomass of underground plant parts in the diet did not vary between seasons (F1,424 = 1.9, P = 0.17). Due to the seasonal differences in diet, the MRPP analyses to compare taxonomic composition among regions were conducted separately for each season and comparisons between seasons were conducted within regions.

Taxonomic Composition of the Diet

Grasses (Poaceae) were the most common leafy material consumed in all regions during both fall-

winter (Table 2.3) and spring (Table 2.4) and the most common fruits consumed in all regions

during both seasons except the CF in spring, where oak acorns (Quercus sp.) dominated the diet

(Table 2.4). Within the grass family, wheat (Triticum aestivum) was the most abundant seed in

all regions in fall-winter and the most abundant seed in the NR and BM regions in spring; corn 18

(Zea mays) was the most abundant seed in the CF and KM regions in spring. Other seed taxa that

comprised >5% of the diet in spring included bristlegrass (Setaria sp.; CF), cockspur grass

(Echinochloa sp.; KM), and oat (Avena sp.; NR and BM). The only other plant families that comprised >5% of aggregate percent dry mass (all food categories combined) included Rosaceae

(NR, CF, and BM), Pinaceae (NR, CF, and BM), Fagaceae (CF and KM) and Asteraceae (KM) in fall-winter and Fabaceae (NR, BM and KM), Fagaceae (CF), Asteraceae (NR, CF), Pinaceae

(BM), and Ranunculaceae (BM) in spring. Grasshoppers (Acrididae) were the most abundant invertebrate taxa in fall-winter comprising between 2.5 to 6.2 of aggregate percent dry mass

(Table 2.3), while snails (Gastropoda) were the most abundant invertebrate in spring but never

exceeded 3% aggregate dry mass (Table 2.4).

Some foods were frequently consumed but did not significantly contribute to the overall biomass in the diet. In fall-winter, snowberry (Symphoricarpos spp.), plum (Prunus spp.) and knotweed (Polygonum spp.) fruits occurred in over 10% of crops but constituted <1% aggregate dry mass. In spring, buttercup (Ranunculus sp.), dandelion (Taraxacum offinale), and starwort

(Stellaria sp.) flowers occurred in over 10% of crops but comprised less than 5% aggregate dry mass (Table 2.6). Both in spring and fall-winter, beetles (Coleoptera sp.), spiders (Araneida sp.)

and ants, bees and wasps (Hymenoptera sp.) occurred in >10% of crops (Table 2.5 and 2.6). In

fall-winter, invertebrates in larval and chrysalis stages were frequently consumed (6.8%, Table

2.5) while pill bugs (Armadillidiidae sp.) were frequently consumed in spring (7.5%, Table 2.6).

The specific taxa that comprised the diet of wild turkeys differed among regions in both fall (MRPP, A = 0.03, P < 0.001) and spring (MRPP, A = 0.04, P < 0.001). In fall-winter, the

KM region had the most distinctive diet with seven foods identified by the indicator species analysis (Table 2.7), but of those only sunflower (Helianthus sp.) and oak acorns comprised >5%

of the diet (Table 2.3). Species that were both indicative and comprised >5% aggregate dry mass

of diet in other regions in fall included Pinaceae seed in the NR region, hawthorn berries

(Crataegus spp.) in the BM region and bristlegrass seed in the CF region. Diet composition was 19

less distinctive among regions in spring than fall-winter (Table 2.7) with no taxa identified as

indicative of the BM region and only sunflower seed (NR region), acorns (CF region) and corn

(KM region) being both distinctive and comprising >5% of the diet in the other regions (Table

2.4).

Diet composition also differed between seasons in all regions (MRPP: NR, A = 0.05, P <

0.001; CF, A = 0.06, P < 0.001; BM, A = 0.02, P < 0.001; KM, A = 0.12, P < 0.001). In the NR region the three most dominant foods in the fall-winter were grass leaf, pine seed and wheat seed

(Table 2.9), whereas the three most abundant foods in spring were grass leaf, wheat seed and

buttercup leaf (40.9%). Eight taxa were indicative of the fall-winter (Table 2.8) although only

pine seed and hawthorn berries contributed greater than 5% dry mass to the diet (Table 2.9).

Buttercup seed, leaf and flowers constituted 11.7% of the diet and were indicative of spring in the

region. Knotweed seed constituted only 1.2% of the fall-winter diet but it occurred in 37.7% of crops.

In the CF region the three most dominant foods in the fall-winter were wheat, bristlegrass

and acorn seed while acorns, grass leaf and bulbous bluegrass bulbs (Poa bulbosa) were the most

common food items in spring (Table 2.10). Six food items were indicative of the fall-winter

although only wheat, bristlegrass and pine seed contributed over 5% dry mass to the diet (Table

2.10). In spring, although starwort flowers were indicative and occurred in 25% of crops, they

only contributed 3% dry mass to the diet (Table 2.8 and 2.10). Although acorn was indicative of

spring, it comprised a large percentage of the diet in both seasons (Table 2.8; spring 27.7%, fall-

winter 8.9%).

In the BM region grass leaf and wheat seed was abundant in both seasons as well as

hawthorn berries in fall-winter and clover leaf in spring. Oat and pine seed comprised almost 5%

of the diet in both seasons making them relatively important but not indicative of either season.

Only 4 foods were indicative of season denoting many common foods between seasons (Table 20

2.8). Buttercup and starwort flowers were unique, important and frequently occurred in the

spring contributing over 10% dry mass to the diet (Table 2.4, 2.8 and 2.11).

In the KM region numerous foods were indicative of seasons (Table 2.8; fall-winter n =

18, spring n = 7, summer n = 7). The most dominant foods in fall-winter were grass leaf, acorns

and wheat seed although sunflower seed and cockspur grass seed and Acrididae (namely grasshoppers) each also contributed over 5% dry mass to the diet (Table 2.12). Brome (Bromus

sp.), sunflower and poison oak-ivy seed all occurred in over 20% of crops. In spring the most

abundant foods were grass leaf, corn and clover leaf, which combined, contributed to over 35% of

the diet. No other single food type was indicative and comprised over 5% of spring diet but

starwort and chickweed flowers occurred in 21.9% of crops. In summer, turkeys consumed more

fruit-seed and invertebrates and less leaf and flowers than in any other season. Summer diet was dominated by grass leaf and seed, blackberries (Rubus spp.), manzanita berries (Arctostaphylos spp.), grasshoppers and snails (Table 2.12).

Table 2.1. Sample sizes of wild turkey crops collected in Oregon and Washington between 2009 and 2011 during 3 seasons (fall-winter: 22 September through March 19, spring: 20 March through 19 June, and summer: 20 June through September 21) summarized by region* and collection year. Summer collection only occurred in the KM region.

Region NR CF BM KM Total 2010 2011 2010 2011 2010 2011 2009 2010 2011 Fall- Winter 33 42 11 19 56 33 0 11 16 221 Spring 41 19 12 19 8 17 30 36 57 239 Summer 0 0 0 0 0 0 0 14 16 30

Table 2.2. Mean aggregate percent dry mass of foods consumed by wild turkeys (mean ± SE) in Oregon and Washington between 2009 and 2011 during 2 seasons (fall-winter: 22 September through March 19 and spring: 20 March through 19 June) in 4 regions*.

Season Food Type Region Fall-Winter Spring Annual Mean Leafa NR 16.5 ± 0.9 34.4 ± 5.1 23.5 ± 2.4 CF 10.9 ± 0.7 27.6 ± 1.6 19.1 ± 1.1 BM 23.5 ± 1.3 56.2 ± 3.9 29.7 ± 2.4 KM 14.1 ± 0.6 31.9 ± 0.9 28.7 ± 0.8 Combined 18.2 ± 1.9 34.2 ± 2.4 26.0 ± 1.6 Fruit-seedb NR 69.0 ± 3.6 42.0 ± 3.2 58.6 ± 4.5 CF 70.9 ± 5.8 43.5 ± 7.3 57.4 ± 5.0 BM 66.1 ± 3.9 23.0 ± 8.4 57.9 ± 3.9 KM 65.4 ± 6.9 43.3 ± 3.6 47.7 ± 3.2 Combined 67.7 ± 2.3 41.2 ± 2.7 54.7 ± 1.9 Flowerc NR 2.8 ± 2.1 6.2 ± 2.6 4.1 ± 1.7 CF 0.2 ± 0.1 14.0 ± 4.3 7.0 ± 2.3 BM 0.3 ± 0.2 11.0 ± 5.7 2.4 ± 1.9 KM 4.2 ± 2.3 10.6 ± 2.2 9.3 ± 1.8 Combined 1.6 ± 0.6 10.1 ± 1.5 5.8 ± 0.8 Invertebrate NR 3.1 ± 0.9 9.8 ± 3.4 5.7 ± 1.1 CF 9.0 ± 4.1 5.3 ± 2.3 7.2 ± 2.6 BM 5.2 ± 1.7 1.9 ± 1.8 4.6 ± 1.4 KM 9.5 ± 4.8 4.2 ± 1.2 5.3 ± 1.4 Combined 5.5 ± 1.1 5.4 ± 1.1 5.5 ± 0.8 Root-bulbd NR 0.5 ± 0.2 3.0 ± 2.0 1.5 ± 1.0 CF 3.0 ± 2.3 8.1 ± 4.8 5.5 ± 3.1 BM 1.7 ± 1.2 3.5 ± 3.3 2.0 ± 1.5 KM 2.5 ± 2.5 0.1 ± 0.1 0.6 ± 0.5 Combined 1.6 ± 0.4 2.1 ± 0.8 1.9 ± 0.5 Miscellaneouse NR 8.1 ± 1.2 4.6 ± 0.8 6.6 ± 0.9 CF 6.0 ± 4.1 1.5 ± 0.9 11.0 ± 1.1 BM 3.2 ± 0.9 4.4 ± 1.5 3.4 ± 0.9 KM 4.3 ± 1.9 9.9 ± 1.5 8.2 ± 0.9 Combined 5.4 ± 0.7 7.0 ± 1.1 6.1 ± 0.7

* The Northern Rockies-Plateau Region (NR) is located Northeast Washington, the Eastern Cascade Foothills Region (CF) includes south-central Washington and north-central Oregon, the Blue Mountain-Plateau Region (BM) includes northeast Oregon and southeast Washington and the Klamath Mountain Region (KM) is located in southwestern Oregon. a Includes broadleaf, conifer, succulent, true grasses, sedge, rush leaves but excludes bulb scales b Includes true fruits, seeds, achenes, true berries, drupes, pomes, accessory and aggregate fruits c Includes simple flowers, inflorescences and composite flower heads d Includes roots, bulb and tubers and connected bulb scales e Includes items too small for identification, animal feed and human foods

Region Overall Taxa NR CF BM KM Mean LEAFa Poaceae Unknown 11.9 ± 2.5 5.9 ± 1.9 17.3 ± 3.2 8.9 ± 3.4 12.8 ± 1.6 Fabaceae Trifolium 2.8 ± 0.9 4.1 ± 2.8 4.2 ± 1.8 0.3 ± 0.2 3.2 ± 0.8 Other 1.8 ± 0.7 0.9 ± 0.4 2.0 ± 0.4 4.9 ± 2.1 2.2 ± 0.5 Subtotal 16.5 ± 0.9 10.9 ± 0.7 23.5 ± 1.3 14.1 ± 0.6 18.2 ± 1.9 FRUIT-SEEDb Poaceae Triticum 11.1 ± 3.0 13.2 ± 5.4 8.3 ± 2.6 7.2 ± 4.0 9.8 ± 1.7 Avena 5.0 ± 1.9 0.5 ± 0.4 5.5 ± 2.0 4.1 ± 3.5 4.5 ± 1.1 Zea 2.1 ± 0.9 8.6 ± 4.2 2.7 ± 1.4 4.8 ± 3.2 3.5 ± 0.9 Setaria 1.1 ± 0.9 9.8 ± 4.9 0.9 ± 0.9 0.4 ± 0.4 2.1 ± 0.8 Echinochloa 0.2 ± 0.1 3.7 ± 2.4 1.2 ± 1.2 5.1 ± 3.1 1.7 ± 0.7 Bromus 1.0 ± 0.7 Tr 2.4 ± 1.2 0.8 ± 0.4 1.4 ± 0.5 Secale 0.0 0.0 3.1 ±1.8 0.0 1.2 ± 0.7 Unknown 6.2 ± 2.0 3.5 ± 2.8 4.2 ± 1.7 1.5 ± 1.0 4.5 ± 1.1 Other 3.2 ± 1.6 1.9 ± 1.1 4.7 ± 1.9 2.3 ± 1.1 3.4 ± 1.2 Rosaceae Crataegus 5.3 ± 1.9 0.7 ± 0.7 10.4 ± 2.5 0.0 6.1 ± 1.2 Prunus 1.9 ± 1.1 2.5 ± 1.4 2.0 ± 1.0 1.7 ± 1.0 1.9 ± 0.6 Rosa 3.6 ± 1.8 0.4 ± 0.4 2.9 ± 1.5 0.0 2.4 ± 0.6 Pinaceae Unknown 14.4 ± 3.1 6.4 ± 3.3 5.5 ± 2.1 tr 8.0 ± 1.5 Fagaceae Quercus 0.6 ± 0.6 8.9 ± 4.0 0.0 12.5 ± 5.5 3.0 ± 1.0 Asteraceae Helianthus 1.5 ± 0.8 0.4 ± 0.3 0.0 6.1 ± 3.4 1.4 ± 0.6 Ericaeae Arctostaphylos tr 0.0 3.5 ± 1.6 1.1 ± 1.0 1.5 ± 0.6 Polygonaceae Rumex 1.2 ± 1.0 4.1 ± 3.4 1.0 ± 0.6 0.0 1.3 ± 0.6 Fabaceae Unknown 1.6 ± 1.2 0.5 ± 0.3 0.7 ± 0.7 2.6 ± 2.6 1.6 ± 0.5 Unknown Seed 2.8 ± 1.4 1.9 ± 1.1 3.5 ± 1.7 0.7 ± 0.3 2.6 ± 0.8 Other 6.2 ± 1.7 3.9 ± 0.9 3.6 ± 1.0 14.5 ± 3.9 5.8 ± 0.8 Subtotal 69.0 ± 3.6 70.9 ± 5.8 66.1 ± 3.9 65.4 ± 6.9 67.7 ± 2.3 FLOWER Subtotal 2.8 ± 2.1 0.2 ± 0.1 0.3 ± 0.2 4.2 ± 2.3 1.6 ± 0.6 ROOT-BULBd Subtotal 0.5 ± 0.2 3.0 ± 2.3 1.7 ± 1.2 2.5 ± 2.5 1.6 ± 0.4 INVERTEBRATE Orthoptera Acrididae 2.5 ± 0.9 4.2 ± 2.9 3.3 ± 1.2 6.2 ± 3.6 3.5 ± 0.8 Other 0.6 ± 0.2 4.8 ± 3.4 1.9 ± 0.5 3.3 ± 1.9 2.0 ± 0.8 Subtotal 3.1 ± 0.9 9.0 ± 4.1 5.2 ± 1.7 9.5 ± 4.8 5.5 ± 1.1 FEED 1.0 ± 0.7 0.0 0.1 ± 0.1 0.0 0.4 ± 0.3 MISC.e 7.1 ± 1.4 6.0 ± 4.1 3.1 ± 0.9 4.3 ± 1.9 5.0 ± 0.7

Table 2.3 (Continued) * The Northern Rockies-Plateau Region (NR) is located Northeast Washington, the Eastern Cascade Foothills Region (CF) includes south-central Washington and north-central Oregon, the Blue Mountain-Plateau Region (BM) includes northeast Oregon and southeast Washington and the Klamath Mountain Region (KM) is located in southwestern Oregon. a Includes broadleaf, conifer, succulent, true grasses, sedge, rush leaves but excludes bulb scales b Includes true fruits, seeds, achenes, true berries, drupes, pomes, accessory and aggregate fruits c Includes simple flowers, inflorescences and composite flower heads d Includes roots, bulb and tubers and connected bulb scales e Includes items too small for identification

Region Overall Taxa NR CF BM KM Mean LEAFa Poaceae Unknown 16.2 ± 3.7 17.4 ± 5.6 31.7 ± 8.3 13.4 ± 2.1 16.3 ± 1.8 Fabaceae Trifolium 3.6 ± 1.5 4.0 ± 3.2 9.3 ± 5.1 8.7 ± 1.7 6.9 ± 1.2 Ranunculaceae Unknown 4.1 ± 2.6 0.5 ± 0.4 2.7 ± 2.5 1.8 ± 0.8 2.2 ± 0.8 Other 10.5 ± 2.6 5.7 ± 0.9 12.5 ± 3.2 8.0 ± 2.1 8.8 ± 1.9 Subtotal 34.4 ± 5.1 27.6 ± 1.6 56.2 ± 3.9 31.9 ± 0.9 34.2 ± 2.4 FRUIT-SEEDb Poaceae Zea 5.3 ± 2.8 6.7 ± 3.4 0.4 ± 0.4 13.3 ± 2.6 9.4 ± 1.7 Triticum 14.2 ± 4.4 1.7 ± 1.6 9.4 ± 6.5 3.2 ± 1.2 6.2 ± 1.4 Avena 2.6 ± 1.8 Tr 4.8 ± 4.8 1.0 ± 0.6 1.6 ± 0.7 Sorghum 0.9 ± 0.7 1.5 ± 1.5 0.0 1.7 ± 0.7 1.3 ± 0.5 Echinochloa 0.1 ± 0.1 0.0 0.0 2.1 ± 1.0 1.2 ± 0.6 Unknown 2.1 ± 2.0 0.8 ± 0.5 1.2 ± 0.9 3.5 ± 1.4 3.4 ± 0.9 Other 1.2 ± 1.0 0.2 ± 0.1 0.1 ± 0.1 5.9 ± 2.2 3.9 ± 1.0 Fagaceae Quercus 0.0 27.7 ± 7.6 0.8 ± 0.8 3.6 ± 1.4 5.7 ± 1.4 Asteraceae Helianthus 5.6 ± 2.3 0.0 0.0 1.2 ± 0.7 1.8 ± 0.7 Other tr 1.4 ± 1.4 0.1 ± 0.1 2.7 ± 0.5 1.1 ± 0.6 Fabaceae Unknown 1.6 ± 1.1 0.0 0.1 ± 0.1 2.9 ± 1.2 1.9 ± 0.7 Pinaceae Unknown 3.9 ± 2.3 0.6 ± 0.5 5.1 ± 4.4 0.3 ± 0.2 1.6 ± 0.7 Other 4.5 ± 1.7 2.9 ± 2.1 1.0 ± 0.3 1.9 ± 3.2 2.1 ± 0.7 Subtotal 42.0 ± 3.2 43.5 ± 7.3 23.0 ± 8.4 43.3 ± 3.6 41.2 ± 2.7 FLOWERc Asteraceae Taraxacum 3.1 ± 2.0 5.5 ± 3.6 0.5 ± 0.5 1.9 ± 1.0 2.6 ± 0.8 Other 0.2 ± 0.1 1.2 ± 1.0 0.0 2.1 ± 0.9 1.4 ± 1.0 Ranunculaceae 1.0 ± 0.8 0.5 ± 0.2 5.4 ± 3.8 3.4 ± 1.1 2.6 ± 0.7 Caryophyllaceae Stellaria tr 3.0 ± 1.7 4.8 ± 4.6 0.6 ± 0.3 1.2 ± 0.5 Other 1.9 ± 0.8 3.8 ± 1.2 0.3 ± 0.3 2.6 ± 1.1 2.3 ± 0.6 Subtotal 6.2 ± 2.6 14.0 ± 4.3 11.0 ± 5.7 10.6 ± 2.2 10.1 ± 1.5 ROOT-BULBd Poaceae Poa bulbosa 2.7 ± 2.0 7.8 ± 4.5 tr 0.1 ± 0.1 2.0 ± 0.9 Other 0.3 ± 0.3 0.3 ± 0.4 3.5 ± 3.3 0.0 0.1 ± 0.1 Subtotal 3.0 ± 2.0 8.1 ± 4.8 3.5 ± 3.3 0.1 ± 0.1 2.1 ± 0.8 INVERTEBRATE Gastropoda Unknown 0.7 ± 0.7 2.8 ± 2.6 1.0 ± 1.0 1.0 ± 0.4 1.2 ± 0.5 Other 9.1 ± 3.4 2.5 ± 0.6 0.9 ± 0.6 3.2 ± 1.1 4.2 ± 1.0 Subtotal 9.8 ± 3.4 5.3 ± 2.3 1.9 ± 1.8 4.2 ± 1.2 5.4 ± 1.1 FEED 1.6 ± 1.6 0.0 0.0 2.2 ± 7.0 1.6 ± 0.7 e MISC. 3.0 ± 1.7 1.5 ± 0.9 4.4 ± 1.5 7.7 ± 1.3 5.4 ± 0.8

Table 2.4 (Continued) * The Northern Rockies-Plateau Region (NR) is located Northeast Washington, the Eastern Cascade Foothills Region (CF) includes south-central Washington and north-central Oregon, the Blue Mountain-Plateau Region (BM) includes northeast Oregon and southeast Washington and the Klamath Mountain Region (KM) is located in southwestern Oregon. a Includes broadleaf, conifer, succulent, true grasses, sedge, rush leaves but excludes bulb scales b Includes true fruits, seeds, achenes, true berries, drupes, pomes, accessory and aggregate fruits c Includes simple flowers, inflorescences and composite flower heads d Includes roots, bulb and tubers and connected bulb scales e Includes items too small for identification

Table 2.5. Percent occurrence of foods consumed in the fall and winter (22 September through March 19) by wild turkeys in Oregon and Washington by region* between 2009 and 2011 (n = 221). Only foods that occurred in over 1% of the all samples are included. Region Taxa NR CF BM KM Overall LEAFa Poaceae Unknown 85.7 89.7 82.6 82.8 85.1 Fabaceae Trifolium 36.4 37.9 23.6 31.0 31.2 Vicia 2.6 3.4 3.5 13.8 4.5 Unknown 0.0 0.0 1.2 6.9 1.4 Pinaceae Unknown 14.3 13.8 10.4 17.2 13.1 Apiaceae Daucus 1.3 3.4 4.7 13.8 4.5 Asteraceae Taraxacum 6.5 0.0 4.7 0.0 4.1 Lactuca 5.2 0.0 3.5 3.4 3.6 Polygonum Rumex 1.3 0.0 3.5 3.4 2.3 Unknown Leaf 44.2 48.3 45.3 44.8 45.2 FRUIT-SEEDb Pinaceae Pseudotsuga menziesii 1.3 6.9 7.0 3.4 4.5 Unknown 37.7 24.1 18.6 6.9 24.4 Poaceae Triticum 23.4 37.9 14.0 31.0 22.6 Avena 18.2 6.9 14.0 13.8 14.8 Bromus 9.1 13.8 10.5 24.1 12.2 Zea 10.4 20.7 8.1 17.2 11.8 Echinochloa 3.9 13.8 3.5 13.8 6.8 Setaria 6.5 20.7 1.2 3.4 5.9 Poa bulbosa 1.3 3.4 4.7 3.4 3.2 Avena sativa 1.3 3.4 5.8 0.0 3.2 Avena fatua 3.9 6.9 0.0 0.0 2.7 Achnatherum 5.2 0.0 2.3 3.4 3.2 Sorghum 2.6 3.4 0.0 6.9 2.3 Hordeum 1.3 3.4 2.3 0.0 2.3 Vulpia 0.0 6.9 1.2 3.4 1.8 Alopecurus 1.3 0.0 3.5 0.0 1.8 Secale 0.0 0.0 3.5 0.0 1.4 Poa 1.3 0.0 1.2 3.4 1.4 Bromus tectorum 1.3 0.0 2.3 0.0 1.4 Aegillops cylindrica 0.0 0.0 3.5 0.0 1.4 Unknown 19.4 20.6 17.4 10.1 18.1 Rosaceae Crataegus 15.6 3.4 29.1 0.0 17.6 Prunus 14.3 17.2 10.5 20.7 14.5 Rosa 5.2 0.0 11.6 0.0 6.8 Rosa canina 1.3 3.4 5.8 0.0 3.2 Caprifoliaceae Symphoricarpos 18.2 6.9 17.4 20.7 16.7 Polygonaceae Rumex 11.7 10.3 5.8 0.0 7.7

Table 2.5 (Continued) Region Taxa NR CF BM KM Overall LEAFa Rumex acetosella 0.0 0.0 3.5 0.0 1.4 FRUIT-SEEDb Polygonaceae Unknown 26.0 20.7 11.6 0.0 16.7 Asteraceae Helianthus 7.8 6.9 1.2 20.7 6.8 Madia 0.0 27.6 1.2 3.4 4.5 Taraxacum 2.6 0.0 1.2 0.0 1.4 Unknown 3.9 0.0 3.5 13.8 4.5 Toxicodendron Unknown 2.6 13.8 1.2 20.7 5.9 Fagaceae Quercus 1.3 20.7 0.0 17.2 5.4 Ericaeae Arctostaphylos 1.3 0.0 8.1 10.3 5.0 Vaccinium 2.6 6.9 2.3 3.4 3.2 Arbutus 0.0 0.0 0.0 13.8 1.8 Boraginaceae Lithospermum 5.2 3.4 2.3 3.4 3.6 ruderale Unknown 2.6 0.0 1.2 0.0 1.4 Fabaceae Unknown 6.5 3.4 2.3 6.9 4.5 Apiaceae Daucus 1.3 3.4 0.0 10.3 2.6 Anthriscus caucalis 1.3 0.0 0.0 10.3 1.8 Cyperaceae Carex 1.3 6.9 1.2 0.0 1.8 Ranunculaceae Unknown 0.0 0.0 3.5 0.0 1.4 Equisetaceae Equisetum 0.0 0.0 2.3 3.4 1.4 Unknown 39.0 37.9 36.0 34.5 37.5 FLOWERc Asteraceae Taraxacum 10.4 13.8 4.7 10.3 8.6 Tragopogon 3.9 6.9 4.7 0.0 4.0 Cichorieae 3.9 0.0 1.2 6.9 2.7 Lactuca 2.6 3.4 2.3 0.0 2.3 Brassicaceae Draba verna 2.6 0.0 0.0 3.4 1.4 Solanaceae Unknown 2.6 3.4 0.0 0.0 1.4 Unknown Flower 3.9 0.0 3.5 0.0 2.7 ROOT-BULBd Poaceae Poa bulbosa 16.9 31.0 7.0 10.3 14.0 Melica bulbosa 6.5 6.9 11.6 3.4 8.1 Trifolium Trifolium 3.9 0.0 1.2 3.4 2.3 subterraneum Unknown Tuber 5.2 6.9 15.1 13.8 10.4 Bulb 0.0 13.8 4.7 3.4 4.1 INVERTEBRATE Orthoptera Acrididae 20.8 31.0 30.2 27.6 26.7 Gryllidae 2.6 0.0 2.3 0.0 1.8 29

Table 2.5 (Continued) Region Taxa NR CF BM KM Overall INVERTEBRATE Araneida Unknown 10.4 24.0 5.8 10.3 10.4 Hemiptera Pentatomidae 3.9 3.4 2.3 3.4 3.2 Unknown 3.9 13.8 1.2 13.8 5.4 Coleoptera Curculionidae 7.9 3.4 3.5 0.0 4.5 Carabidae 2.6 0.0 3.5 10.3 3.6 Coccinella 3.9 0.0 1.2 6.9 2.7 septempunctata Gastrophysa cyanea 3.9 3.4 0.0 3.4 2.3 Cicindelindae 0.0 0.0 3.5 0.0 1.4 Tenebrionidae 1.3 6.9 1.2 0.0 1.8 Lucanidae 0.0 3.4 3.5 0.0 1.8 Anatis rathvoni 0.0 0.0 3.5 0.0 1.4 Hymenoptera Formicidae 5.2 6.9 3.5 3.4 4.5 Vespidae 2.6 0.0 0.0 3.4 1.4 Ichneumonidae 2.6 3.4 0.0 0.0 1.4 Unknown 1.3 10.3 1.2 3.4 2.7 Gastropoda Unknown 2.6 10.3 2.3 6.9 4.1 Mantodea Mantidae 3.9 10.3 0.0 3.4 3.2 Oligochaete Unknown 0.0 10.3 0.0 13.8 3.2 Diptera Unknown 1.3 3.4 4.7 3.4 3.2 Diplopoda Unknown 1.3 3.4 2.3 3.4 2.3 Isopoda Armadillidiidae 0.0 3.4 3.5 3.4 2.3 Unknown Larva-Chrysalis 2.6 6.9 11.9 3.4 6.8 Unknown Invertebrate 15.6 6.9 19.8 6.9 14.9 FEED 2.6 0.0 1.2 0.0 1.4 SHOT 7.8 3.4 5.8 3.4 5.9

Table 2.6. Percent occurrence of foods consumed in spring (20 March through 19 June) by wild turkeys (mean ± SE) in Oregon and Washington by region* between 2009 and 2011 (n = 239). Only foods that occurred in over 1% of the all samples are included. Region Taxa NR CF BM KM Overall LEAFa Poaceae Unknown 74.0 71.4 90.0 80.7 78.8 Fabaceae Trifolium 32.0 17.9 30.0 56.1 42.9 Vicia 4.0 7.1 5.0 14.0 9.9 Asteraceae Taraxacum 10.0 10.7 10.0 15.8 13.2 Ranunculaceae Ranunculus 14.0 10.7 5.0 12.2 11.8 Pinaceae Unknown 8.0 3.6 0.0 9.6 7.5 Unknown Leaf 64.0 57.1 50.0 52.3 55.7 FRUIT-SEEDb Poaceae Zea 16.0 10.7 5.0 29.8 21.7 Triticum 24.0 7.1 10.0 12.3 14.1 Sorghum 10.0 3.6 0.0 10.5 8.5 Poa 6.0 10.7 0.0 9.6 8.0 Echinochloa 2.0 0.0 0.0 7.9 4.7 Avena 8.0 3.6 0.0 3.5 4.2 Alopecurus 0.0 0.0 0.0 6.1 3.3 Bromus 0.0 0.0 0.0 2.6 1.4 Avena fatuca 0.0 0.0 0.0 2.6 1.4 Unknown 6.0 28.6 0.0 29.7 23.6 Ranunculaceae Ranunculus A 10.0 10.7 0.0 13.2 10.8 Ranunculus B 2.0 0.0 0.0 1.8 1.4 Fagaceae Quercus 0.0 39.3 5.0 6.1 9.0 Asteraceae Helianthus 14.0 0.0 0.0 4.4 5.7 Taraxacum 0.0 0.0 5.0 9.6 5.7 Madia 2.0 3.6 0.0 0.9 1.4 Unknown 4.0 7.1 0.0 3.5 3.8 Pinaceae Unknown 10.0 3.4 10.0 2.6 5.2 Equisetaceae Equisetum 6.0 3.6 0.0 0.9 2.4 Junceae Juncus 0.0 0.0 0.0 3.5 1.9 Berberidaceae Berberis 0.0 0.0 0.0 3.5 1.9 Ericaeae Unknown 0.0 0.0 0.0 2.6 1.4 Caprifoliaceae Symphoricarpos 4.0 0.0 0.0 0.9 1.4 Polygonaceae Unknown 0.0 3.6 0.0 1.8 1.4 Fabaceae Unknown 2.0 0.0 0.0 1.8 1.4 Boraginaceae Lithospermum 2.0 3.6 0.0 0.9 1.4 ruderale Apiaceae Daucus 2.0 0.0 0.0 1.7 1.4 Rubiaceae Galium 0.0 0.0 0.0 2.6 1.4 Unknown Seed 18.0 17.9 10.0 13.2 14.6 31

Table 2.6 (Continued) Region Taxa NR CF BM KM Overall FLOWER Ranunculaceae Ranunculus 16.0 21.4 30.0 20.2 20.3 Asteraceae Taraxacum 18.0 17.9 5.0 21.9 18.9 Tragopogon 0.0 3.6 0.0 2.6 1.9 Unknown 4.0 3.6 0.0 3.5 3.3 Caryophyllaceae Stellaria 4.0 25.0 15.0 12.3 12.3 Cerastium 4.0 3.6 0.0 9.6 6.6 Holosteum 2.0 3.6 0.0 0.9 1.4 umbellatum Brassicaceae Draba verna 2.0 3.6 0.0 1.8 1.9 Idaha scapigera 2.0 3.6 0.0 0.9 1.4 Unknown 0.0 0.0 0.0 2.6 1.4 Liliaceae Calochortus 0.0 3.6 0.0 1.8 1.4 Unknown 2.0 7.1 5.0 3.5 3.8 Portulacaceae Claytonia 2.0 7.1 5.0 0.0 1.9 Unknown 4.0 7.1 0.0 0.0 1.9 Unknown Flower 6.0 3.6 5.0 7.9 6.6 ROOT-BULBd Poaceae Poa bulbosa 20.0 25.0 15.0 5.2 12.2 INVERTEBRATE Coleoptera Diabrotica 0.0 0.0 0.0 18.4 9.9 undecimpuntata Elateridae 10.0 14.3 0.0 6.1 7.5 Coleoptera 10.0 17.9 0.0 4.4 7.5 Carabidae 4.0 3.6 0.0 1.7 2.4 Araneida Unknown 4.0 14.3 0.0 10.5 8.5 Isopoda Armadillidiidae 4.0 14.3 0.0 8.8 7.5 Gastropoda Unknown 2.0 10.7 5.0 9.6 7.5 Hymenoptera Formicidae 2.0 10.7 0.0 7.9 6.1 Ichneumonidae 4.0 7.1 0.0 0.0 1.9 Unknown 4.0 3.6 0.0 2.6 2.8 Orthoptera Acrididae 4.0 3.6 0.0 6.1 4.7 Oligochaete Unknown 4.0 10.7 0.0 4.4 4.7 Diplopoda Unknown 10.0 0.0 0.0 3.5 4.2 Hemiptera Pentatomidae 2.0 7.1 0.0 1.8 2.4 Unknown 0.0 10.7 0.0 2.6 2.8 Diptera Unknown 2.0 3.6 0.0 0.9 1.4 Unknown Larva-Chrysalis 0.0 3.6 5.0 0.9 1.4 Unknown 4.0 14.3 10.0 20.2 14.6 FEED 2.0 0.0 0.0 3.5 2.4 SHOT 2.0 3.4 0.0 1.8 1.9

Season Food Type Taxa Common Name Region IV P-value Fall- Fruit- Seedb Pinaceae Pine NR 20.3 0.01 Winter Madia Tarweed CF 26.8 <0.01 Setaria Bristlegrass CF 16.2 <0.01 Vulpia Fescue CF 6.1 0.04 Crataegus Hawthorn BM 18.1 <0.01 Helianthus Sunflower KM 13.8 <0.01 Arbutus Madrone KM 13.8 <0.01 Asteraceae Unknown aster KM 11.3 0.03 Daucus Wild carrot KM 10.0 <0.01 Anthriscus caucalis Bur chervil KM 9.7 <0.01 Toxicodendron Poison oak-ivy KM 9.5 0.02 Quercus Acorn KM 9.3 0.02 Root-Bulbd Poa bulbosa Bulbous CF 18.9 <0.01 bluegrass Spring Fruit-Seedb Helianthus Sunflower NR 12.4 0.02 Quercus Acorn CF 28.4 <0.01 Zea Corn KM 21.1 0.03 Flowerc Stellaria Starwort CF 21.4 0.01 Invertebrate Diabrotica undecimpuntata W. spotted KM 18.4 0.01 cucumber beetle Hemiptera True bug CF 10.2 0.01

Table 2.8. Foods consumed by wild turkeys indicative of 3 seasons (fall-winter: 22 September through March 19, spring: 20 March through 19 June and summer: 20 June through September 21) within 4 regions* in Oregon and Washington between 2009 and 2011. Taxa displayed had observed indicator values (IV) with p-values <0.05.

Region Season Taxa Common Name Plant parta IV P-value NR Fall-winter Unknown Seed Fruit 32.0 <0.01 Pinaceae Pine Fruit 30.3 <0.01 Polygonaceae Knotweed Fruit 27.3 <0.01 Symphoricarpos Snowberry Fruit 17.3 0.01 Crataegus Hawthorn Fruit 16.9 <0.01 Prunus Plum Fruit 15.6 0.01 Rumex Dock Fruit 11.7 0.03 Acrididae Grasshopper Invertebrate 16.5 0.03 Spring Unknown Leaf Leaf 49.7 <0.01 Ranunculus Buttercup Leaf 14.0 <0.01 Ranunculus Buttercup Seed 12.2 <0.01 Ranunculus Buttercup Flower 16.0 <0.01 Elateridae Click beetle Invertebrate 10.0 <0.01 Diplopoda Millipede Invertebrate 9.4 0.02 CF Fall-winter Triticum Wheat Fruit 32.8 0.01 Madia Tarweed Fruit 26.4 0.01 Pinaceae Pine Fruit 21.5 0.04 Setaria Bristlegrass Fruit 20.7 0.02 Prunus Plum Fruit 17.2 0.05 Acrididae Grasshopper Invertebrate 30.8 <0.01 Spring Quercus Acorn Fruit 29.0 0.05 Stellaria Starwort Flower 25.0 0.01 Ranunculus Buttercup Flower 21.4 <0.01 BM Fall-winter Crataegus Hawthorn Fruit 29.1 0.02 Acrididae Grasshopper Invertebrate 30.2 0.02 Spring Ranunculus Buttercup Flower 30.0 <0.01 Stellaria Starwort Flower 14.9 0.01 KM Fall-winter Daucus Wild carrot Leaf 13.8 <0.01 Fabaceae Pea Leaf 6.9 0.04 Unknown Seed Fruit 21.9 <0.01 Bromus Brome Fruit 20.7 <0.01 Symphoricarpos Snowberry Fruit 20.4 <0.01 Zea Corn Fruit 20.4 0.03 Helianthus Sunflower Fruit 16.4 0.01 Prunus Plum Fruit 15.7 <0.01 Arctostaphylos Manzanita Fruit 13.8 <0.01 Arbutus Madrone Fruit 13.8 <0.01 Quercus Acorn Fruit 13.5 0.01 Toxicodendron Poison oak-ivy Fruit 13.1 0.01 Asteraceae Aster Fruit 11.5 0.02 Avena Oat Fruit 11.5 0.05 Anthriscus caucalis Bur chervil Fruit 10.3 0.01 Daucus Wild carrot Fruit 8.8 0.04 Acrididae Grasshopper Invertebrate 26.6 <0.01 34

Table 2.8 (Continued) Region Season Taxa Common Name Plant parta IV P-value KM Fall-winter Carabidae Ground beetle Invertebrate 8.4 0.04 KM Spring Trifolium Clover Leaf 41.3 <0.01 Unknown Leaf Leaf 29.8 0.04 Ranunculus Buttercup Fruit 13.2 0.03 Ranunculus Buttercup Flower 19.3 0.01 Stellaria Starwort Flower 12.3 0.04 Diabrotica W. spotted Invertebrate 15.7 0.04 undecimpuntata cucumber beetle Hemiptera Stink bug Invertebrate 11.1 0.03 Rubus Blackberry Fruit 50.3 <0.01 Madia Tarweed Fruit 10.0 0.01 Vulpia Fescue Fruit 9.7 0.02 Achnatherum Needlegrass Fruit 9.0 0.03 Vicia Vetch Flower 13.6 <0.01 Vespidae Wasp Invertebrate 9.3 0.02 Chrysomelidae Leaf beetle Invertebrate 6.6 0.04 * The Northern Rockies-Plateau Region (NR) is located Northeast Washington, the Eastern Cascade Foothills Region (CF) includes south-central Washington and north-central Oregon, the Blue Mountain-Plateau Region (BM) includes northeast Oregon and southeast Washington and the Klamath Mountain Region (KM) is located in southwestern Oregon. a Includes broadleaf, conifer, succulent, true grasses, sedge, rush leaves but excludes bulb scales b Includes true fruits, seeds, achenes, true berries, drupes, pomes, accessory and aggregate fruits c Includes simple flowers, inflorescences and composite flower heads d Includes roots, bulb and tubers and connected bulb scales

Table 2.9. Mean aggregate percent dry mass of foods consumed by wild turkeys (mean ± SE) in Northeast Washington (Northern Rockies-Plateau [NR] region: Pend Oreille, Stevens, Ferry, Lincoln and Spokane Counties) during the fall-winter (22 September through March 19) and spring (20 March through 19 June) between 2009 and 2011 (n = 135 crops). Only foods that comprised greater than 1% of the annual mean are included.

Season Annual Food Type Taxa Fall-Winter Spring Mean LEAFa Poaceae Unknown 11.9 ± 2.5 16.2 ± 3.7 13.5 ± 2.1 Fabaceae Trifolium 2.8 ± 0.9 3.6 ± 1.5 3.1 ± 0.8 Ranunculaceae Unknown 0 10.5 ± 2.6 1.6 ± 1.0 Other 1.8 ± 0.7 4.1 ± 2.6 5.3 ± 1.2 Subtotal 16.5 ± 0.9 34.4 ± 5.1 23.5 ± 2.4 FRUIT-SEEDb Poaceae Triticum 11.1 ± 3.0 14.2 ± 4.4 12.3 ± 2.5 Avena 5.0 ± 1.9 2.6 ± 1.8 4.1 ± 1.4 Zea 2.1 ± 0.9 5.3 ± 2.8 3.4 ± 1.2 Unknown 6.2 ± 2.0 2.1 ± 2.0 4.4 ± 1.3 Other 5.5 ± 1.6 2.2 ± 1.1 4.6 ± 1.8 Pinaceae Unknown 14.4 ± 3.1 3.9 ± 2.3 10.4 ± 2.2 Rosaceae Crataegus 5.3 ± 1.9 0 3.2 ± 1.2 Prunus 1.9 ± 1.1 0 1.1 ± 0.7 Rosa 3.6 ± 1.8 0 2.2 ± 1.2 Asteraceae Helianthus 1.5 ± 0.8 5.6 ± 2.3 2.9 ± 1.0 Fabaceae Unknown 1.6 ± 1.2 1.6 ± 1.1 1.6 ± 0.9 Polygonaceae Rumex 1.2 ± 1.0 0 1.1 ± 0.6 Unknown Seed 2.8 ± 1.4 0.2 ± 0.1 1.8 ± 0.8 Other 6.8 ± 1.9 4.6 ± 1.6 5.5 ± 1.2 Subtotal 69.0 ± 3.6 42.0 ± 3.2 58.6 ± 4.5 c FLOWER Asteraceae Taraxacum 0.4 ± 0.4 3.1 ± 2.0 1.5 ± 0.8 Centaurea 2.0 ± 1.5 0 1.3 ± 0.9 Other 0.4 ± 0.1 3.1 ± 1.7 1.3 ± 0.7 Subtotal 2.8 ± 2.1 6.2 ± 2.6 4.1 ± 1.7 ROOT-BULBd Poaceae Poa bulbosa 0.2 ± 0.1 2.7 ± 2.0 1.2 ± 0.8 Other 0.3 ± 0.2 0.3 ± 0.3 0.3 ± 0.2 Subtotal 0.5 ± 0.2 3.0 ± 2.0 1.5 ± 1.0 INVERTEBRATE Orthoptera Acrididae 2.5 ± 0.9 1.0 ± 0.9 1.9 ± 0.6 Other 0.6 ± 0.2 8.8 ± 2.3 3.8 ± 1.3 Subtotal 3.1 ± 0.9 9.8 ± 3.4 5.7 ± 1.1 FEED 1.0 ± 0.7 1.6 ± 1.6 1.2 ± 0.8 MISC.e 7.1 ± 1.4 3.0 ± 1.7 5.4 ± 1.1 a Includes broadleaf, conifer, succulent, true grasses, sedge, rush leaves but excludes bulb scales b Includes true fruits, seeds, achenes, true berries, drupes, pomes, accessory and aggregate fruits c Includes simple flowers, inflorescences and composite flower heads d Includes roots, bulb and tubers and connected bulb scales e Includes items too small for identification 36

Table 2.10. Mean aggregate percent dry mass of foods consumed by wild turkeys (mean ± SE) in the Eastern Cascade Foothills (CF) region, south-central Washington (Skamania and Klickitat Counties) and north-central Oregon (Hood River, Wasco, Sherman and Gilliam Counties), during the fall-winter (22 September through March 19) and spring (20 March through 19 June) between 2009 and 2011 (n = 61 crops). Only foods that comprised greater than 1% of the annual mean are included.

Season Annual Food Type Taxa Fall-Winter Spring Mean LEAFa Poaceae Unknown 5.9 ± 1.9 7.4 ± 5.6 11.5 ± 3.0 Fabaceae Trifolium 4.1 ± 2.8 4.0 ± 3.2 4.0 ± 2.1 Other 0.9 ± 0.4 6.2 ± 1.9 3.6 ± 1.0 Subtotal 10.9 ± 0.7 27.6 ± 1.6 19.1 ± 1.1 FRUIT-SEEDb Poaceae Zea 8.6 ± 4.2 6.7 ± 3.4 7.7 ± 2.9 Triticum 13.2 ± 5.4 1.7 ± 1.6 7.6 ± 3.0 Setaria 9.8 ± 4.9 0 5.0 ± 2.5 Echinochloa 3.7 ± 2.4 0 1.9 ± 1.2 Other 2.5 ± 1.3 2.1 ± 1.5 4.1 ± 1.2 Fagaceae Quercus 8.9 ± 4.0 27.7 ± 7.6 18.2 ± 4.4 Pinaceae Unknown 6.4 ± 3.3 0.6 ± 0.5 3.4 ± 1.7 Polygonaceae Unknown 2.2 ± 1.6 0.3 ± 0.3 1.3 ± 0.8 Rumex 4.1 ± 3.4 <0.1 2.1 ± 1.8 Rosaceae Prunus 2.5 ± 1.4 0 1.3 ± 0.7 Unknown Seed 1.9 ± 1.1 0.3 ± 0.1 1.0 ± 0.6 Other 2.5 ± 1.1 2.1 ± 1.1 1.9 ± 1.2 Subtotal 70.9 ± 5.8 43.5 ± 7.3 57.4 ± 5.0 FLOWERc Asteraceae Taraxacum 0.1 ± 0.1 5.5 ± 3.6 2.8 ± 1.8 Caryophyllaceae Stellaria 0 3.0 ± 1.7 1.5 ± 0.8 Other <0.1 2.1 ± 1.6 1.0 ± 1.1 Other 0.1 ± 0.1 3.4 ± 1.2 1.7 ± 1.0 Subtotal 0.2 ± 0.1 14.0 ± 4.3 7.0 ± 2.3 ROOT-BULBd Poaceae 1.0 ± 0.8 7.8 ± 4.5 4.4 ± 2.3 Other 2.0 ± 0.9 0.3 ± 0.4 1.1 ± 0.2 Subtotal 3.0 ± 2.3 8.1 ± 4.8 5.5 ± 3.1 INVERTEBRATE Orthoptera Acrididae 4.2 ± 2.9 <0.1 2.1 ± 1.5 Coleoptera Lucanidae 2.7 ± 2.7 0 1.4 ± 1.4 Gastropoda Unknown 0.1 ± 0.1 2.8 ± 2.6 1.4 ± 1.3 Other 2.0 ± 1.1 2.5 ± 0.6 3.3 ± 0.6 Subtotal 9.0 ± 4.1 5.3 ± 2.3 7.2 ± 2.6 MISC.e 6.0 ± 4.1 1.5 ± 0.9 3.8 ± 1.6 a Includes broadleaf, conifer, succulent, true grasses, sedge, rush leaves but excludes bulb scales b Includes true fruits, seeds, achenes, true berries, drupes, pomes, accessory and aggregate fruits c Includes simple flowers, inflorescences and composite flower heads d Includes roots, bulb and tubers and connected bulb scales e Includes items too small for identification 37

Table 2.11. Mean aggregate percent dry mass of foods consumed by wild turkeys (mean ± SE) in the Blue Mountains-Plateau (BM) region, northeast Oregon (Morrow, Umatilla, Union, Wallowa, Grant and Baker Counties) and southeast Washington (Walla Walla, Columbia, Garfield, and Asotin Counties), during the fall-winter (22 September through March 19) and spring (20 March through 19 June) between 2009 and 2011 (n = 114 crops). Only foods that comprised greater than 1% of the annual mean are included.

Season Annual Food Type Taxa Fall-Winter Spring Mean LEAFa Poaceae Unknown 17.3 ± 3.2 31.7 ± 8.3 20.0 ± 3.0 Fabaceae Trifolium 4.2 ± 1.8 9.3 ± 5.1 5.2 ± 1.7 Other 2.0 ± 0.4 15.2 ± 2.9 4.5 ± 2.2 Subtotal 23.5 ± 1.3 56.2 ± 3.9 29.7 ± 2.4 FRUIT-SEEDb Poaceae Triticum 8.2 ± 2.6 9.4 ± 6.5 8.4 ± 2.4 Avena 5.5 ± 2.0 4.8 ± 4.8 5.4 ± 1.8 Secale 3.1 ± 1.8 0 2.5 ± 1.5 Zea 2.7 ± 1.4 0.4 ± 0.4 2.2 ± 1.2 Bromus 2.4 ± 1.2 0 1.9 ± 1.0 Alopecurus 1.5 ± 1.1 0 1.2 ± 0.9 Poa 1.3 ± 0.8 0 1.0 ± 0.6 Unknown 4.2 ± 1.7 1.2 ± 0.9 3.6 ± 1.4 Other 4.1 ± 1.7 0.1 ± 0.1 1.1 ± 0.9 Rosaceae Crataegus 10.4 ± 2.5 0 8.4 ± 2.0 Rosa 2.9 ± 1.5 0 2.3 ± 1.2 Prunus 2.0 ± 1.0 0 1.6 ± 0.8 Pinaceae Unknown 5.5 ± 2.1 5.1 ± 4.4 5.4 ± 1.9 Ericaeae Arctostaphylos 3.5 ± 1.6 0 2.8 ± 1.3 Unknown Seed 3.5 ± 1.7 1.0 ± 0.9 3.0 ± 1.4 Other 5.3 ± 2.1 1.0 ± 0.9 4.6 ± 1.4 Subtotal 66.1 ± 3.9 23.0 ± 8.4 57.9 ± 3.9 FLOWERc Ranunculaceae Unknown 0 5.4 ± 3.8 1.0 ± 0.7 Caryophyllaceae Stellaria 0 4.8 ± 4.6 1.0 ± 0.9 Other 0.3 ± 0.2 0.8 ± 0.6 0.4 ± 0.1 Subtotal 0.3 ± 0.2 11.0 ± 5.7 2.4 ± 1.9 ROOT-BULBd 1.7 ± 1.2 3.5 ± 3.3 2.0 ± 1.5 INVERTEBRATE Orthoptera Acrididae 3.3 ± 1.2 0 2.7 ± 1.0 Unknown Larva- 1.6 ± 1.1 0.4 ± 0.4 1.4 ± 0.9 Chrysalis Other 0.3 ± 0.1 1.5 ± 1.1 0.5 ± 0.2 Subtotal 5.2 ± 1.7 1.9 ± 1.8 4.6 ± 1.4 MISC.e 3.2 ± 0.9 4.4 ± 1.5 3.4 ± 0.9 a Includes broadleaf, conifer, succulent, true grasses, sedge, rush leaves but excludes bulb scales b Includes true fruits, seeds, achenes, true berries, drupes, pomes, accessory and aggregate fruits c Includes simple flowers, inflorescences and composite flower heads d Includes roots, bulb and tubers and connected bulb scales e Includes items too small for identification 38

Season Annual Food Type Taxa Fall- Winter Spring Summer Mean LEAFa Poaceae Unknown 8.9 ± 3.4 13.4 ± 2.1 8.7 ± 2.1 11.9 ± 1.5 Fabaceae Trifolium 0.3 ± 0.2 8.7 ± 1.7 0.4 ± 0.1 5.9 ± 1.2 Ranunculaceae Unknown 0.1 ± 0.1 1.8 ± 0.8 <0.1 1.2 ± 0.5 Other 4.8 ± 2.3 8.0 ± 2.1 0.2 ± 0.1 6.1 ± 1.1 Subtotal 14.1 ± 0.6 31.9 ± 0.9 9.3 ± 0.4 25.1 ± 1.1 FRUIT-SEEDb Poaceae Zea 4.8 ± 3.2 13.3 ± 2.6 0 9.7 ± 1.9 Triticum 7.2 ± 4.0 3.2 ± 1.2 4.2 ± 2.3 4.1 ± 1.1 Echinochloa 5.1 ± 3.1 2.1 ± 1.0 0 2.3 ± 0.9 Poa 0.1 ± 0.1 2.5 ± 1.1 0.1 ± 0.1 1.7 ± 0.7 Sorghum 1.6 ± 1.5 1.7 ± 0.7 0 1.4 ± 0.5 Avena 4.1 ± 3.5 1.0 ± 0.6 0 1.4 ± 0.7 Unknown 2.0 ± 1.1 5.2 ± 1.5 31.3 ± 6.2 9.1 ± 1.7 Other 1.3 ± 0.6 1.7 ± 0.7 4.9 ± 1.1 1.9 ± 0.5 Fagaceae Quercus 12.5 ± 5.5 3.6 ± 1.4 0 4.5 ± 1.3 Fabaceae Unknown 2.6 ± 2.6 2.9 ± 1.2 0 2.3 ± 0.9 Asteraceae Helianthus 6.1 ± 3.4 1.2 ± 0.7 <0.1 1.8 ± 0.8 Ericaeae Arctostaphylos 1.1 ± 1.0 <0.1 5.8 ± 3.4 1.2 ± 0.6 Rosaceae Rubus 0.3 ± 0.3 0 22.0 ±5.6 3.8 ± 1.1 Other 16.6 ± 2.5 4.9 ± 1.2 2.2 ± 0.7 6.4 ± 1.2 Subtotal 65.4 ± 6.9 43.3 ± 3.6 70.4 ± 3.1 51.6 ± 2.9 Flowerc Asteraceae Taraxacum 0.3 ± 0.3 1.9 ± 1.0 1.9 ± 0.9 1.7 ± 0.7 Ranunculaceae Unknown <0.1 3.4 ± 1.1 0 2.2 ± 0.8 Other 3.9 ± 1.6 3.7 ± 1.9 0.1 ± 0.1 5.0 ± 1.8 Subtotal 4.2 ± 2.3 10.6 ± 2.2 2.0 ± 0.9 8.1 ± 1.2 ROOT-BULBd 2.5 ± 2.5 0.1 ± 0.1 0.8 ± 0.6 0.6 ± 0.5 INVERTEBRATE Gastropoda Unknown 3.1 ± 3.1 1.0 ± 0.4 8.1 ± 3.9 2.6 ± 0.9 Orthoptera Acrididae 6.2 ± 3.6 <0.1 6.9 ± 3.6 2.2 ± 0.9 Other 0.2 ± 0.1 3.2 ± 1.1 0.2 ± 0.1 2.2 ± 0.8 Subtotal 9.5 ± 4.8 4.2 ± 1.2 15.2 ± 6.6 7.0 ± 1.9 FEED 0 2.2 ± 0.9 0 1.5 ± 0.8 MISCe 4.3 ± 1.1 7.7 ± 2.0 2.3 ± 0.5 6.1 ± 0.9 a Includes broadleaf, conifer, succulent, true grasses, sedge, rush leaves but excludes bulb scales b Includes true fruits, seeds, achenes, true berries, drupes, pomes, accessory and aggregate fruits c Includes simple flowers, inflorescences and composite flower head d Includes roots, bulb and tubers and connected bulb scales e Includes items too small for identification 39

DISCUSSION

This is the largest, most temporally and spatially diverse study to examine the diet of wild turkeys in the Pacific Northwest and provides quantitative information on how wild turkeys fit into native ecosystems in the region. Past descriptions of diet composition have provided baseline information on wild turkey diet but this analysis specifically highlights seasonal and regional differences and measures the exclusiveness of species to each season and region. Consistent with the geographic and seasonal breadth of the study design, I identified a high number of taxa in the diet of wild turkeys. I detected 123 plant taxa including 34 families and 90 genera of plants, and

35 invertebrate taxa. This level of diversity is similar to past turkey diet studies of similar sample size (Dalke et al. 1942, Korschgen 1973, Litton 1977). Similar taxa were identified in this study as in past diet studies in Oregon (Wengert et al. 2009) and Washington (Mackey 1981) but this study had a higher diversity (n = 21 taxa, Mackey 1981; n = 94 taxa, Wengert et al. 2009).

Though sampling multiple seasons and regions may increase the number of taxa observed, my taxonomic identification erred on being cautious. Conservative identification to family or genus rather than species results in a lower number of observed taxa but minimizes identification mistakes. For example, there are numerous widespread native and non-native varieties of hawthorn in Oregon and Washington. Systematic diagnostic keys require leaf blade edge and stamen counts, but turkeys consumed only the berries leaving identification, without genetic confirmation, difficult.

Major Food Types

As I predicted, there were consistent seasonal trends among study regions in the percent composition of major food types in the diet of wild turkeys. Turkeys consumed 46.8% more leaf,

84.2% more flowers, and 39.1% less fruit in the spring than fall-winter. These patterns are consistent with past wild turkey food habit studies across the US (reviewed in Schemnitz 1956,

Schorger 1966, Korschgen 1967, Eaton 1992, Hurst 1992). Past studies often group disparate parts of a plant (e.g., leaf and fruits) together when reporting diet information, but nutritional 40

content varies among parts of a plant. For example, the protein content of green vegetation (25.9-

41.5%) is high compared to seeds (6.6-14.1%, Ely and Raveling 2011), while the lipid content of seeds (24.9% crude lipid, Leif and Smith 1993) is generally higher than green vegetation (4.4%,

Leif and Smith 1993) or specifically grass leaf (1.2% crude fat, Budeau et al. 1991).

Additionally, the way turkeys forage on plants can have different impacts on plant performance like growth and reproduction (Kaspari 1990, Robbins 1983). Given these considerations, I recommend flowers, green browse, fruits, and underground portions of plants be reported separately in future studies of turkey diet.

In three of the four study regions, percent composition of invertebrates in the diet of turkeys was higher in the fall-winter than spring, which was contrary to my prediction. In this study, female turkeys only accounted for 11% of spring samples therefore we did not have enough sex specific data to test for diet shifts attributable to reproduction. With a sample heavily weighted towards males, it is probable that increased protein needs of females were not represented. Additionally, the fall-winter season included late summer months, when invertebrates in the Pacific Northwest are still abundant (Haggard and Haggard 2006). Most wild turkey diet studies have found invertebrates most prevalent in spring (reviewed in Schemnitz

1956, Schorger 1966, Korschgen 1967, Eaton 1992, Hurst 1992), but studies in mild climates such as South Carolina, Texas and New Mexico have found higher percent invertebrates fall

(Baughman and Guynn 1993, York and Schemnitz 2003, Peterson 2007). Mild climates and sampling in September and October when temperatures were still high throughout Oregon and

Washington (NOAA 2013) likely means invertebrates are available longer into the fall and therefore more abundant in the diet. Percent invertebrates in the diet decreased thoughout the fall-winter season (Evans-Peters, unpublished data). In the NR region invertebrate consumption was substantially higher in spring. This may be because male and female turkeys in colder climates where snow pack is high, such as northeast Washington, tend to remain at lower 41

elevations even in spring (Hurst 1992) and invertebrate abundance has been shown to be higher at

lower elevations (Straw et al. 2009).

No vertebrates were detected in any turkey collected within our study regions. One western fence lizard (Sceloporus occidentalis) was found in a crop submitted from a turkey collected near Bend, Oregon. The Pacific Northwest supports a number of threatened and endangered reptiles and amphibians that could be preyed on by turkeys. A comprehensive review of turkey diet studies found that fragments of amphibian and reptiles occurred in 15 of 45,363 food habit samples reviewed between 1941 and 1996 (WDFW 2005a). Herptiles are most active in the spring and early fall (Csuti et al. 1997) when many of my turkeys were collected. Given my relatively large sample size (n = 536) I would expect the frequency of occurrence to be larger than 1 if turkeys were commonly foraging on vertebrates. Although Central Oregon (i.e., the

Bend area) was not included within my study it borders the Eastern Cascade Foothills and the

Blue Mountain Level III ecoregions (Omemik 1987) and both ecoregions were included in my study (Ch. 1, Fig. 1.1). Thus, I would not expect that the occurrence of vertebrates in the diet around Bend to substantially differ in regions in eastern Oregon and Washington that I did sample. The abundance of amphibians is substantially higher west of the Cascade Mountains. I collected 175 samples west of the Cascades and no vertebrates detected in the diet (Csuti et al.

1997).

Taxonomic Composition of the Diet

Though diet composition of wild turkeys differed regionally and seasonally, some taxa were common in the diet in all regions throughout the year. Most notably, the leaves and fruits of plants in the grass family (Poaceae) were the most abundant foods consumed in all regions and seasons, ranging from 28.3-50.3% aggregate dry mass in the diet. This pattern is common across the range of wild turkeys (reviewed in Schemnitz 1956, Schorger 1966, Korschgen 1967, Eaton

1992 and Hurst 1992). The ubiquity of Poaceae in the diet precluded them from being highlighted by the MRPP and ISA analyses, which emphasized identifying differences in diet 42

composition. Within Poaceae, cultivated seeds including, wheat, oat, corn, and rye constituted

17-19.0% of the overall diet. Though the protein content of cultivated grass seeds is relatively low (corn: 8.8-8.9%, Joyner et al. 1987, Ely and Raveling 2011) it is easily digestible and carbohydrate rich making it a dependable food source (Petrie et al. 1998).

Turkeys in all regions consumed clover more than any other broadleaf and consumption was highest in spring. Clovers are protein and mineral rich and unlike grasses they retain high digestibility as a plant ages because there is a continual generation of new leaves from stolons.

Conversely, the digestibility of grasses declines with plant age (Soegaard 1994). The favorable digestive characteristics of clover make it among the most common plants recommended for creating and improving wildlife habitat (NRCS 2006). Clovers may be especially valuable for females when protein needs for reproduction are high, especially during early spring in climates where temperatures freeze and invertebrates are generally not abundant (Sinclair and Chown

2005).

Hypotheses to explain regional and seasonal differences in diet composition include differences in regional and seasonal food availability, seasonal changes in turkey habitat use, and changes in nutritional needs of turkeys throughout their annual cycle. The common seed consumed varied among regions consistent with major differences in plant composition among regions. Thus, acorns were most abundant in the CF and KM regions where oak woodlands predominate while pine seeds were most abundant in the NR region. In the CF region bristlegrass and fescue seed and bulbous bluegrass bulbs also constituted a significant percentage of the diet indicative of open grasslands associated with the Columbia Plateau (Küchler 1964). Turkeys in the BM region consumed significantly more berries, specifically hawthorn, than in any other region. While various species of native and non-native hawthorn occur throughout both states,

Douglas’ hawthorn (Crataegus douglasii), a native species, is common and widespread east of the Cascade Mountains and likely the main species of hawthorn in the BM region. In the KM region, numerous common understory shrubs including blackberry, poison oak, snowberry, 43

manzanita and madrone, and acorns were represented in the diet (Appendix V) indicative of the

Oregon white oak -poison oak and Oregon white oak-western serviceberry-snowberry habitats as

defined by Thelineus (1968).

Fleshy fruits, namely berries, were abundant in each region but the dominant genera

varied (NR, hawthorn and rose (Rosa sp.); CF, poison oak-ivy and plum (Prunus sp.); BM, hawthorn and snowberry; KM, madrone and plum). Fleshy fruit seeds are high in dietary lipids

(Snow and Snow 1988) and pulp is high in dietary carbohydrates and thus is known to be important to migratory fattening in many birds (Bairlein 2002). Fleshy fruits are only available for short periods and decompose rapidly compared to seeds, which are readily available on the landscape and often consumed by turkeys at varying stages of maturity. In this study, turkeys were found to occasionally consume extremely large quantities of fleshy fruits (rosehips 50.5g,

manzanita 76.6g, hawthorn 58.8g). Therefore, turkeys may consume large amounts of fleshy

fruits when given the opportunity regardless of region.

Snails were a common invertebrate in the spring diet in all regions. Snails constituted

1.2% of the overall diet (range 0.7 ± 0.7 to 2.8 ± 2.6), but females consumed more (4.7%) than

males (0.06%). One female crop contained over 25g of snails, suggesting they will consume

large quantities when available. Female wild turkeys require increased protein and calcium to

facilitate egg formation and land snail shells significantly aid in egg shell formation due to the

high levels of calcium (Pattee and Beasom 1981, Hurst 1992, Gill 2007). Consistent with this

explanation, one study found that female turkeys in the process of laying eggs consumed nine

times more snails than pre-laying and post-laying females (Beasom and Patee 1978) and snails

have been found to contribute more than 50% of the diet of some females when they were laying

eggs (Sterns 2010).

In contrast to spring, Orthoptera (grasshoppers and crickets) were the most common taxa

consumed during fall in all regions. My results are consistent with past findings (reviewed in

Schemnitz 1956, Schorger 1966, Korschgen 1967, Eaton 1992, Hurst 1992). Most grasshoppers 44

and crickets congregate on vegetation that is still green in the late summer and early fall, though

some Northwest species (Arphia conspersa, orange-winged grasshopper) ears in the late spring

(Haggard and Haggard 2006). Large invertebrates that congregate may be a profitable food

source especially in the early fall when juveniles are actively foraging with adults in large flocks

(Hurst 1992).

Seasonal differences in foods consumed may reflect seasonal patterns in habitat use. For

example, in fall-winter wild turkeys in all regions increased consumption of forest associated

fruits (e.g., pine, manzanita, hawthorn, snowberry; Appendix II-IV) consistent with a decrease in

use of open areas and an increase in use of forested habitat types. In eastern portions of the

turkey’s distribution, this pattern is prevalent from Virginia to Texas (Speake et al. 1975,

Kennamer et al. 1980, Campo 1983). In areas with harsher winter conditions, represented by much of eastern Oregon and Washington, turkeys winter at low elevations and move to higher elevation sites for breeding, nesting and brood rearing (ODFW 2004). In NE Washington (NR region) the decreased consumption of lowland grass species in the spring (e.g., brome, bristlegrass, Achnatherum sp. [needlegrass]; Appendix II) may be representative of the change of habitat types. In contrast, in climates with mild winter conditions, such as in southwest Oregon

(KM region), differences in diet may be more representative of seasonally abundant foods because turkeys often spend the entire year within the same general area (ODFW 2004).

MANAGEMENT IMPLICATIONS

Our methods prohibited us from identifying all foods found in turkey crops to species. If I had identified all foods to the species level, now subtle regional differences in diet may have become more pronounced. In cases where a genus contains native, rare, and exotic species, such resolution may be needed if the objective is to determine the effects of wild turkey foraging on plant population demographics; however, it is likely not necessary for understanding how turkeys forage to meet their nutritional needs. I also lacked data comparing males and females, but I 45

hypothesize such data would only reveal differences in the relative consumption of various taxa

but would not reveal entirely different species of foods in the diet.

My results identify plants and invertebrates that are commonly consumed by turkeys,

providing guidelines for turkey habitat management. Findings from this study reaffirm that wild

turkeys are flexible in their diet consuming a large number of plant and invertebrate taxa.

However, important foods varied by region and could serve to guide habitat management. I

recommend planting a combination of large seed producing pines (e.g. ponderosa pine [Pinus

ponderosa], Douglas-fir), native fruit producing hardwoods (e.g. oaks, Oregon crab apple [Malus

fusca], choke cherry [Prunus virginiana], Indian plum [Oemleria cerasifomis]), shrubs that

provide ample berries (e.g. snowberry, poison oak, hawthorn), large seed producing grasses (e.g.

Idaho fescue [Festuca idahoensis], California brome [Bromus carinotus], blue wildrye [Elymus

glaucus], Indian ricegrass [Achnatherum hymenoides]) native grasses that remain green

throughout the year and a combination of broad leaf plants such as clovers and buttercups

(Appendix VI).

Wild turkeys rarely consume vertebrates in the Pacific Northwest. Data were not

collected in Western Washington or Northwest Oregon but most amphibian and reptiles that occur in that region have distributions that extend south into the KM region and east into the CF region (Csuti et al. 1997). The low occurrence of reptiles and amphibians in the diet is consistent with past turkey diet studies and provides evidence that while turkeys do eat vertebrates, they are a very small component of their overall diet.

I did not detect any threatened or endangered species in the diet of wild turkeys in

Oregon and Washington but some plant taxa in the diet were only identified to family or genus, some of which contained species of concern. For example, turkeys in all regions consumed flowers of mariposa lilies (Calochortus sp.). In Oregon there are seven mariposa lilies that are listed as state endangered, threatened or candidate species (NRCS 2012). Though lilies did not contribute to large percentage of the diet (0.06-0.5% aggregate dry mass in spring), they occurred 46

in as much as 5% of the crops collected during spring. Additionally, Owyhee clover (Trifolium owyheense), bartonberry (Rubus bartonianus) and Southern Oregon buttercup (Ranunculus austrooreganus) are all listed as threatened and sensitive Oregon plants (NRCS 2012) and though these species were not detected in the diet, plants in those genera were abundant in the diet suggesting they would likely be consumed by turkeys.

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SEED DISPERSAL BY WILD TURKEYS (Meleagris gallopavo) IN OREGON AND

WASHINGTON

Chapter 3

SEED DISPERSAL

Seed dispersal is an important life history adaptation in plants (Fuentes 2000, Ellis 2005, Orrock et al. 2006, Pollux et al 2005). Dispersal contributes to seed survival at the individual plant level

(Bossard 1991, Rey and Alcantara 2000, Gosper et al. 2005): genetic heterogeneity at the plant population level (Furnier et al. 1987, Jordano and Godoy 2000, Godoy and Jordano 2001), and species composition at the community level (Ellis 2005, Orrock et al. 2006, Pollux et al 2005).

To enhance dispersal many species of plants have evolved to use birds as agents of seed dispersal

(Howe and Smallwood 1982, Fleming and Kress 2011).

There is considerable variability in how seeds survive passage through the gut of birds.

Plant species from like habitats with comparable seed properties respond differently to gut passage through the same bird species (Mueller and van der Valk 2002, Soons et al. 2008,

Traveset et al. 2008, Wongsriphuek et al. 2008, Figuerola et al. 2010). Similarly, seeds of a single plant survive differently when digested by different bird species (Figuerola et al. 2002,

Santamaria et al. 2002, Twigg 2009, Figuerola et al. 2010). Subtle differences in seed properties such as seed coat thickness, lignon content and size and physiologic differences among avian dispersers such as gut retention time, proventriculus pH and gizzard size have significant influences on dispersal (reviewed in Traveset 1998). While some patterns are emerging, it is impossible to predict seed fate by seed properties alone, thus more work is needed across a broader range of avian taxa to develop a clearer understanding of the role birds play in seed dispersal.

Research on birds as seed dispersers has disproportionately focused on tropical frugivores

(Levey et al. 2002, Dennis et al. 2007, Forget et al. 2011) and Anseriformes (van Leeuwen et al. 52

2012, Clausen et al. 2002, Figuerola and Green 2002), leaving some orders of granivorous birds, such as Galliformes, understudied. Galliformes are distributed worldwide, occupy diverse habitats and their diet includes a large percentage of fruit and seed throughout the year (Bent

1932, Eaton 1992). Additionally, many species of Galliformes have been intentionally introduced around the world to support recreational hunting. In the United States there are 18 native species of gallinaceous birds plus another eight species that have been introduced (Eaton

1992). The wild turkey is native to the US but has been introduced outside its native range.

Quantifying the ability of galliformes to disperse seeds of native and exotic plant species is one way of considering the impact of species introductions on ecosystem structure and function

(Howe and Mitri 2004, Gosper et al. 2005).

Research indicates seeds can pass through the digestive system of gallinaceous birds intact (Krefting and Roe 1949, Cole et al. 1995, Penner et al. 1999). Limited studies have identified successful endozoochory by upland birds including ring-necked pheasant (Phasianus colchicus; Krefting and Roe 1949, Cole et al. 1995), chuckar (Colchicus alectoris; Cole et al.

1995), ruffed grouse (Bonasa umbellus; Penner et al. 1999) and northern bobwhite (Colinus viginianus; Krefting and Roe 1946). Conversely, few to no seeds were recovered from California quail (Callipepla californica; Bossard 1991), sharp-tailed grouse (Tympanuchus phasianellus) and wild turkeys (Wald et al. 2005). Simply determining if seeds can pass through the digestive system intact does not quantity the percent of seed recovered or the quality (i.e. seed viability and survival) of that seed. Further research on gallinaceous birds is needed to understand their ecological significance as seed dispersers.

Wild turkeys have large, muscular gizzards designed to mechanically digest seeds, yet given the substantial quantities of seed they consume in fall and winter, they may be important dispersal vectors (reviewed in Schorger 1966, Korschgen 1967, Hurst 1992, Ch. 2). As an introduced game bird in the Pacific Northwest, wild turkeys are of particular interest as they could be performing an ecosystem service by dispersing native plant seeds or conversely, 53

facilitating the spread of non-native plants. There is an abundance of non-native plants in Pacific

Northwest ecosystems that turkeys may encounter. If turkeys co-evolved with non-natives plants

within their respective historic ranges we may expect prior mutualistic relationships to enhance

present dispersal capability. Alternatively, native plant seeds may be less able to survive

digestion, limiting dispersal. The only study to date found that seeds of leafy spurge (Euphoribia

esula) did not survive passage through the gut of turkeys (Wald et al. 2005).

In this chapter, I test if wild turkeys serve as dispersers of plant seed by documenting

species recovered from fecal matter collected in Oregon and Washington. I predicted that few to

no seed would be excreted intact and a small percent would be viable. Additionally, I test how

seed size is associated with seed viability hypothesizing if that large seeds survive gut passage the

likelihood of them being viable is high.

METHODS

I recovered seeds contained within wild turkey fecal samples that had been collected from four

regions in Oregon and Washington, the Northern Rockies-Plateau (NR), Eastern Cascade

Foothills (CF), the Blue Mountains-Plateau (BM), and the Klamath Mountains (KM; Fig. 1.1).

Samples were collected during during 2009-2010 and 2010-2011 the fall-winter period (22

September through March 19) when mature seed was most prevalent in the environment and

when turkeys are most commonly consuming seeds (reviewed in Schorger 1966, Korschgen

1967, Hurst 1992, Ch. 2).

Sample Collection

Fecal samples were collected during a series of one-day trips to various locations in the study regions. During a collection trip, an observer(s) would find a flock of turkeys either while feeding during the day or at a roost in the morning or evening and collect between 30 to 50 fresh feces that were individually placed in labeled freezer bags, transported and cold stored at 4°C or frozen until further processing. Fecal samples were considered fresh if they were soft, moist and 54

dark brown to green in color, usually having white near the tips. Most collection trips were

conducted by volunteers who had been recruited with help from Oregon and Washington’s state

wildlife agencies and the National Wild Turkey Federation. Volunteers received a protocol

explaining fecal sample collection, data sheets and a box of supplies for sampling, and training

from me, via phone (Appendix VIII). Data reported here come from feces gathered during 50 collection trips (NR, n = 16; CF, n = 9; BM, n = 14; KM, n = 10).

In the lab, I processed 30 randomly selected fecal samples from each collection trip after discarding fecal samples that were not whole, potentially contaminated, decomposed, discolored and/or dry to reduce external influences on seed viability. All fecal samples were carefully examined and seeds that appeared to be adhered to the exterior of any feces were removed prior to processing. I gently filtered individual fecal samples through a series of mesh sieves (2mm,

500µm, and 350µm) to separate excreted hard mast, soft mast, succulent material and animal matter. Intact seed retained by sieves was removed and separated from inflorescence by hand.

Seeds were identified to family, genus or species using standard references (Hitchcock and

Cronquist 1973) and the personal experience of R. Halse, curator of the herbarium at Oregon

State University. However, not all seeds could be identified and these were reported as unknown. In situations where there were multiple unknown species in a sample (clearly different, but not identifiable), I report multiple unknowns. Seeds were air dried and cold stored at 4°C.

Statistical Analysis

My final sample included 1,500 feces (30 fecal samples from each of 50 trips). To avoid pseudoreplication of samples collected on a single trip (e.g., multiple feces collected from the same turkey or turkeys within a flock foraging together on the same items), the sample unit for summarizing data was the collection trip (n = 50). For summarizing seed abundance, a sample was defined as the mean number of seeds that were recovered from 30 feces collected during that trip. I calculated percent occurrence as the percentage of samples that contained a species of seed. 55

I combined seeds by species into composite samples for viability testing. Up to 200

intact seeds per species (range = 10-200) were taken to Oregon State University’s Seed

Laboratory for tetrazolium (TZ) testing to estimate the percent of seeds excreted that were viable

(DeVlaming and Proctor 1968, Moore 1985, Mueller and van der Valk 2002). The viability test

differentiated live from dead tissues of the seed embryo on the basis of dehydrogenase enzyme

activity and is a surrogate measure for germination (DeVlaming and Proctor 1968, Moore 1985).

In contrast to seed germination, viability tests can be performed regardless of seed dormancy

levels (Marrero et al. 2007). Viability tests generally overestimate germination rates (Kulik and

Yaklich 1979, Kolasinska et al. 2000); however, I lacked information on the germination

conditions required by most plant taxa in our sample to conduct meaningful germination

experiments. Seed viability was calculated as the percentage of recovered seed that was viable.

All means are reported ± SE.

To assess if seed size was related to viability, I measured seed length, width and height

(to 0.001mm) and mass (0.0001g) on 20 dried seeds from each taxa/species group that were

found in the fecal samples (Soons et al. 2008). Seeds were obtained from wild turkey crops

collected in the fall of 2009 and 2010 (Ch. 2) because sample sizes for the majority of seeds

removed from fecal samples were small and seed characteristics may have been altered during

passage through the gastrointestinal track. Seed volume was calculated from seed length, width

and height measurements by using the equation appropriate for the closest matching geometrical

shape of each seed (i.e. ellipsoid, cylinder, pyramid or irregular prism; Soons et al. 2008). Seed

density was then calculated from volume and mass metrics. To test for differences between seed

size characteristics and percent viability, I conducted correlation analyses using Pearson’s

correlation coefficients (R™; Ramsey and Schafer 2002, Soons et al. 2008). Seed mass and volume were highly correlated (r = 0.95). Both metrics were used to examine relationships because each metric has been found as a significant contributor to successful seed passage

(Traveset et al. 2001, Soons et al. 2008). Seed metrics were log transformed to reduce skewness, 56

improve homogeneity of variance and create a normal distribution. An outlier analysis was used

to identify influential data points based on Cooks Distance, studentized residuals and covariance

ratios (Ramsey and Schafer 2002).

RESULTS

Intact seed was found in 28% of individual feces and 62% of the collection trips; percent

occurrence varied by region being highest in the KM region (90%) followed by the BM region

(79%), the NR region (56%) and the CF region (20%). I recovered 17 identifiable taxa and 4

distinct unknown taxa. The mean number of taxa per sample varied by region (Fig. 3.1; F3,27 =

5.5, P < 0.01) and was highest in the BM region (n = 3.8) followed by the KM region (n = 3.3), the NR region (n = 1.1), and the CF region (n = 0.6). While some taxa were common in samples

(Symphoricarpos sp., 36%; Crataegus sp., 18%; Arctostaphylos sp., 16%), 4 taxa each only occurred in 1 sample (Table 3.1). Regional variation in percent occurrence was high for most

species (i.e. Arctostaphylos sp.). Additionally, unidentified seed was found in 42% of the

samples.

A total of 14,137 seeds were recovered from 31 samples. The most abundant seed recovered was Eragrostis sp., where 9,818 seeds were recovered from one sample, followed by

Symphoricarpos sp. (n = 773 seeds). Excluding the sample which contained Eragrostis sp., I recovered the most seed from the KM region (n = 2,642 seeds), followed by the BM region (n =

1,253 seeds), the NR region (n = 256 seeds), and the CF region (n = 177 seeds). Symphoricarpos sp. was the most abundant seed recovered in the NR region (n = 61 seeds), Echinochloa sp. in the

CF region (n = 52 seeds), Eragrostis sp. (n = 9,810 seeds) followed by Rubus sp. (n = 329 seeds) in the BM region and Arctostaphylos sp. (n = 612 seeds) in the KM region. Based on studentized residuals, Cook’s distance and covariance ratios the sample containing 9,818 Eragrostis sp. seeds was identified as an outlier and removed from all mean seed estimates. The mean number of seeds recovered per sample was 86 ± 23 (n = 50 samples). In samples where seed was recovered, 57

mean seeds per sample was 140 ± 29 and varied by study region (F3,27 = 6.8, P < 0.001; KM, n =

293.6 ± 60.8; BM, n = 113.8 ± 35.5; CF, n= 69 ± 30; RM, n = 28.4 ± 7.9). The mean number of

seeds recovered per feces per sample was 3.0 ± 0.8 (n = 50 samples).

I had 22 taxa of seed tested for viability including 4 unknown taxa; for 9 taxa at least one

seed was viable (41%; Table 3.2). Viability ranged from 2-70% and was highest in the Fabaceae

(pea family, 70%) followed by Toxicodendron sp. (poison oak-ivy, 24.5%) and Symphoricarpos

sp. (snowberry, 11.6%). The viability of the remaining 6 taxa was below 10% (Table 3.2). While

the seeds of some viable taxa were abundant (Fig. 3.1; Symphoricarpos sp., Echinochloa sp.,

Toxicodendron sp.) some viable seed occurred rarely in low numbers (Fig. 3.1; Chenopodium sp.,

Amaranthus sp., Fabaceae sp.).

Percent viability was not correlated with seed volume (r = 0.55, P = 0.13) but was positively correlated with seed mass (Fig 3.2; r = 0.71, P = 0.03). Based on studentized residuals,

Cook’s distance and covariance ratios, Fabaceae sp. was identified as an outlier. Excluding

Fabaceae sp. from the analysis (n = 10 seeds, viability = 70%), percent viability was more

strongly correlated with seed mass (Fig. 3.2; r = 0.81, P = 0.01) though was still not significantly

correlated with volume (r = 0.67, P = 0.07).

Table 3.1. Percent occurrence of seed recovered from wild turkey fecal samples collected at 50 sites, in 4 regions* throughout Oregon and Washington in the fall and winter of 2009-2010 and 2010-2011 (22 September through March 19). Percent occurrence was calculated as the percentage of samples that contained each taxa.

Mean Percent Taxa Name Common Name Region Occurrence NR CF BM KM Fabaceae Pea Family 0 0 0 20 4 Toxicodendron Poison oak-ivy 0 0 29 20 12 Symphoricarpos Snowberry 38 0 64 30 36 Polygonum Knotweed 6 10 14 10 10 Amaranthus Pigweed 13 0 0 10 6 Rubus Blackberry 0 0 43 0 12 Vaccinium Blueberry 0 0 29 0 8 Chenopodium Goosefoot 0 0 0 10 2 Echinochloa Cockspur grass 0 20 0 10 6 Apiaceae Carrot 0 0 21 30 12 Arctostaphylos Manzanita 6 0 0 70 16 Asteraceae Aster 0 0 0 20 4 Crataegus Hawthorn 0 20 50 0 18 Epilobium Willowherb 0 0 0 10 2 Panicum Panicgrass 0 0 29 0 8 Ranunculus Buttercup 0 0 0 20 4 Eragrostis Lovegrass 0 0 7 10 4 Unknown A 0 0 0 10 2 Unknown B 13 0 7 20 10 Unknown C 0 0 0 30 6 Unknown D 0 0 0 10 2 Unknown E 6 0 7 0 4 Other Unknown 25 0 79 60 42 Total percentage of samples with seed 56 20 79 90 62

* NR = Northern Rockies-Plateau Region in northeast Washington; CF = Eastern Cascade Foothills Region in south-central Washington and north-central Oregon; BM = Blue Mountain- Plateau Region in northeast Oregon and southeast Washington and KM = Klamath Mountain Region in southwestern Oregon.

Table 3.2. Viability of seeds recovered from wild turkey fecal samples collected in Oregon and Washington in the fall and winter (22 September through March 19) of 2009-2010 and 2010- 2011. Tetrazolium (TZ) testing was used to estimate viability.

Total Seeds Percent Taxa Name Common Name Recovered No. Tested Viable Fabaceae Pea Family 10 10 70.0 Toxicodendron Poison oak-ivy 119 100 24.5 Symphoricarpos Snowberry 773 100 11.6 Polygonum Knotweed 273 100 7.0 Amaranthus Pigweed 79 25 5.0 Rubus Blackberry 329 200 4.5 Vaccinium Blueberry 213 100 4.2 Chenopodium Goosefoot 51 50 3.9 Echinochloa Cockspur grass 284 100 2.0 Apiaceae Carrot 111 50 0.0 Arctostaphylos Manzanita 615 200 0.0 Asteraceae Aster 42 42 0.0 Crataegus Hawthorn 294 100 0.0 Epilobium Willowherb 118 50 0.0 Panicum Panicgrass 111 50 0.0 Ranunculus Buttercup 79 50 0.0 Eragrostis Lovegrass 9818 100 0.0 Unknown A 367 100 0.0 Unknown B 107 100 0.0 Unknown C 36 34 0.0 Unknown D 13 13 0.0 Unknown E 12 12 0.0

900

800 11.6%

700

600 KM 500 BM 400 4.5% CF 2.0% 300 7.0% 4.2% NR 200 24.5% Number ofNumber seeds 5.0% 100 3.9% 70.0%

Figure 3.1. Total number of viable seeds recovered from 1,500 wild turkey fecal samples in Oregon and Washington in the fall and winter of 2009-2010 and 2010-2011 in 4 regions. Number heading each column is the percent of seeds that were viable. NR = Northern Rockies- Plateau Region in northeast Washington; CF = Eastern Cascade Foothills Region in south-central Washington and north-central Oregon; BM = Blue Mountain-Plateau Region in northeast Oregon and southeast Washington and KM = Klamath Mountain Region in southwestern Oregon.

80.0 All data points Fabaceae 70.0 Fabaceae spp. removed 60.0

50.0

40.0

Percent Viability Percent 30.0

20.0

10.0

0.0 0.0000 0.0050 0.0100 0.0150 0.0200 0.0250 0.0300 Mean Seed Mass (g)

Figure 3.2. Relationship between seed mass (g) and seed viability for seeds recovered from 1,500 wild turkey fecal samples in Oregon and Washington in the fall and winter of 2009-2010 and 2010-2011 (Pearson’s correlation coefficients; r = 0.71, P = 0.03). If Fabaceae sp. is excluded from the analysis then percent viability is more correlated with seed mass (r = 0.81, P = 0.01).

DISCUSSION

This is the first field study to investigate the capacity of wild turkeys to disperse seeds of a broad range of plants. A diet study (Ch. 2) identified the seeds of 62 taxa of plants in my study regions in Oregon and Washington. I found 22 taxa of seed in feces and 9 of those were viable when tested with tetrazolium suggesting turkeys are not a common dispersal vector for the majority of plant seeds they consume. Consistent with that interpretation, intact seed occurred less frequently in individual wild turkey fecal samples (28%) compared to waterfowl (66%), a taxa considered important as seed disperser (Traveset 1998). However when comparing seeds collected from feces of wild birds (i.e. not from controlled feeding trials), the mean number of viable seeds per feces was higher for turkeys (0.12) than waterfowl (0.03; Mueller and van der Valk 2002). Data for turkeys and waterfowl suggest that even birds specialized for feeding on seeds may be important seed dispersers for some plants.

Despite low diversity and a small number of viable seeds recovered, given the size of the turkey population and the quantity of seeds birds consume, the number of seeds dispersed may be considerable. For example, assuming there are 40,000-50,000 turkeys in Oregon (D. Budeau per. comm.), turkeys are dispersing 0.12 viable seeds/feces and defecating 5.1 times/day (Jenson

2003) that equates to 24,480 to 30,600 viable seeds being dispersed across the state, each day, throughout the fall and winter. If turkeys dispersed that amount of seed through the fall-winter sampling period (179 days) then 4.4-5.5 million viable seeds would be dispersed each year in

Oregon. Snowberry was common in the KM region (n = 582 seeds) and had a high percent viability (11.6%). In the KM region, 300 fecal samples were collected (10 samples of 30 feces each), therefore on average, there were 0.23 viable Symphoricarpos sp. seeds/feces. Therefore, extrapolated out over the season (179 days) that equates to 205 Symphoricarpos sp. seeds being successfully dispersed by each turkey in that region.

Of the taxa found viable, most were only identified to genus. Snowberry

(Symphoricarpos sp.), blueberry (Vaccinium sp.) and poison oak-ivy (Toxicodendron sp.) are 63

genera that mainly contain native species in Oregon and Washington while blackberry (Rubus

sp.) cockspur grass (Echinochloa sp.), pigweed (Amaranthus sp.), knotweed (Polygonum sp.) and

goosefoot (Chenopodium sp.) are dominated by upland nonnative species. Himalayan blackberry

(Rubus armeniancus) is the only species classified as a noxious weed in Oregon and Washington

(NWCB 2013, ODA 2013) that could have occurred in my samples.

Seed mass, but not volume, was positively correlated with viability. Some research on waterfowl shows that small seeds, measured by volume (Soons et al. 2008), diameter (Figuerola et al. 2010) or length (Mueller and van der Valk 2002, Brochet et al. 2010), are retrieved in greater numbers and often germinate better (though see Traveset et al. 2001, Traveset and Verdu

2002,Wongsriphuek et al. 2008). In agreement with my findings, others have found that if a large seed is excreted intact, the likelihood of it being viable is relatively higher than for a smaller seed

(Mueller and van der Valk 2002, Traveset et al. 2001, Traveset and Verdu 2002). The discrepancies among studies may be because some used a relatively small number of species per study; most have used fewer than ten species while only two exceeded 20 (DeVlaming and

Proctor 1968, n = 23; Traveset et al. 2001, n = 5; Mueller and van der Valk 2002, n = 8; Soons et al. 2008, n = 23; Wongsriphuek et al. 2008, n = 10, Figuerola et al. 2010, n = 4; Brochet et al.

2010, n = 8). Using small samples sizes to make broad generalizations about linear relationships may be difficult in only a small amount of variation is captured by the data. Meta data analyses suggest small seeds have lower viability than large seeds with similar seed properties (Traveset and Verdu 2002), although small seeds are often retrieved in greater numbers and thus may be represented in greater numbers (Casper et al. 2012).

Seed properties, rather than seed size and mass, may better predict seed survival. It is likely that the toughness of the seed (size, seed coat thickness, permeability and lignin content) dictates seed survival (Traveset 1998). Percent natural detergent fiber (NDF) is often used as a measure of seed toughness because it is an important structural component of the seed coating

(Wongsriphuek et al. 2008). While my sample size was small, the viability for 5 seeds recovered 64

from turkey fecal samples was directly correlated with NDF (Fig. 3.3; Pearson’s correlation

coefficients, r = 0.99, P < 0.001; NDF data taken from Habeck 1991, Wongsriphuek et al. 2008,

Shaw et al. 2010). Thus, a metric that measures overall seed toughness, such as NDF, may

explain variability among seed taxa in viability. I agree with Casper et al. (2012), who suggested

that to generate a better understanding avian plant dispersal relationships, the effect of seed size should be isolated from seed property metrics in future experiments.

Seeds excreted by wild turkeys had lower viability than the same genus of seeds excreted

by waterfowl, suggesting turkeys are less effective seed dispersers than waterfowl when directly

comparing across taxa. Specifically, the viability of Polygonum sp. (turkey 7.0% vs. waterfowl

34.1 ± 2.2%), Echinochloa sp. (turkey 2.0% vs. waterfowl 53.2 ± 0.2%), Chenopodium sp.

(turkey 3.9% vs. waterfowl 22.4 ± 1.7%) and Amaranthus sp. (turkey 5.0% vs. waterfowl 75.0 ±

0%) was lower after passage through turkeys than for mallard (Anas platyrhynchos; DeVlaming

and Proctor 1968, Mueller and van der Valk 2002) or teal (A. crecca L.; Brochet et al. 2010).

Additional comparisons were not possible because of variation in methods among papers

(germination experiments vs. Tetrazolium testing). Assuming the proper germination conditions to provide seeds is known and if seed quality is high, then Tetrazolium testing and germination trials results should be similar (Moore 1985) but it is difficult to meet perfect germination conditions for each species of seed recovered. Standardized methods should be a focus of future research, and I recommend tetrazolium testing be performed on excreted seed in future research in addition to germination trails following methodology by Brochet et al. (2010).

Although the amount of fecal samples collected was large (n = 1,500 feces) the number

of sampling locations was comparatively small (n = 50), thus there are likely species of seed being dispersed by turkey that did not occur in our samples. However, our data provide a useful baseline for generally considering how turkeys fit into Pacific Northwest ecosystems.

MANAGEMENT IMPLICATIONS

I provide evidence that wild turkeys are dispersing the seeds of 9 taxa of plants in the Pacific

Northwest. Wild turkeys are likely dispersing poison oak-ivy, snowberry and blueberry seeds in

Oregon and Washington and species in these genera are mostly native to the region. The extent

this alters the dispersal capabilities of these plants will depend on factors including movement

distances of turkeys relative to other possible dispersal vectors for these plants. Species in the genus Echinochloa are non-native to the U.S. but are not typically of management concern because they are not considered noxious in most areas and are known to provide wildlife forage through abundant seed production (NWCB 2013, ODA 2013). Seeds of species within the

Polygonaceae family are being dispersed and there are three species of Japanese knotweeds

(Fallopia sachalinensis, Polygonum polystachyum and Fallopia japonica) classified as noxious weeds (NWCB 2013, ODA 2013). However, in this study, the size of seeds recovered from

turkeys is not indicative of these species of knotweeds (R. Halse pers comm.). Turkeys are

dispersing the seed of Himalayan blackberry (Rubus armeniancus), a noxious weed (NWCB

2013, ODA 2013), but blackberry seeds are consumed by many birds and the species is already ubiquitous in both states where the physical environment supports blackberry. I found no evidence that turkeys are dispersing the seeds of other taxa listed by the state of Oregon or

Washington as a noxious weed (NWCB 2013, ODA 2013). The most direct way to test for the ability of turkeys to disperse the seed of a specific plant is to conduct controlled feeding trials.

45 Toxicodendron 40

35 Percent NDF Percent

30 Polygonum Chenopodium 25

Echinochloa 20 Crataegus 15 0 5 10 15 20 25 Percent Viability

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CONNECTING WILD TURKEY (Meleagris gallopavo) FORAGING AND SUBSEQUENT

SEED DISPERSAL

Chapter 4

SYNTHESIS

Questions about the possibility for turkeys to impact local flora and fauna in Oregon and

Washington were one motivation for initiating this research project. It was beyond the scope of my research to test that idea directly; rather, my goal was to fill in basic information needs that

could help managers as they consider turkey management in Oregon and Washington. My

research fills the gap in our understanding of wild turkeys in the Pacific Northwest by quantifying

the diet of turkey and their subsequent ability to disperse seeds. My results do not conclusively

document any direct or indirect impacts of turkeys on native plants or wildlife, but do provide a

baseline for considering impacts and future information needs.

The overlap in diet between turkeys and native wildlife is one condition necessary for

competition between species to occur. Turkey diet overlaps considerably with blue grouse

(Dendragapus sp.) and ruffed grouse (Bonasa umellus; Crawford 1986), Western gray squirrel

(Sciurus griseus; Ryan 1995), and black-tailed and mule deer (Odocoileus hemionus; Hanley

1997). However, simply documenting an overlap in diet is not strong evidence that turkeys are

competing with these species for food (Schoener 1982). My data on the diet of turkeys provide a

starting point by identifying diet overlap between turkeys and specific native species, which could

serve as a basis for follow up research if there were concerns about the possibility of competition

between turkeys and a specific native species.

Turkeys may consume native species listed as threatened, endangered, or of concern.

Predation on vertebrates in my study was rare, being documented only once. It is impossible to

prove a negative, but the accumulation of data from this study and many previous studies on the

diet of turkeys (reviewed in Schemnitz 1956, Schorger 1966, Korschgen 1967, Eaton 1992, Hurst

1992) suggests that turkeys should not be considered a high priority threat to endangered 72

vertebrates in Oregon and Washington. In Oregon alone, there are many state and federally listed

invertebrate similar to taxa detected in the diet in this study (n =38 land snails, Stylommatophora;

n = 15 beetles, Coleoptera; n = 29 true bugs, Hemiptera; n = 9 bees, Hymenoptera; n = 20

butterflies, Lepidoptera, n = 2 dragonflies, Odonata and n = 1 grasshopper, Chlealtil aspasma).

Additionally, turkeys consumed unidentified invertebrates in the larval and chrysalis stages of

development. Species identification of invertebrates was outside the scope of this project,

therefore direct impacts to specific invertebrate populations are unknown, but samples were

retained for future identification. I recommend that future research focus more specifically on the

impact of turkey foraging on invertebrate populations.

I did not detect any threatened or endangered species in the diet of wild turkeys in

Oregon and Washington but some plant taxa in the diet were only identified to family or genus,

some of which contained species of concern. For example, turkeys in all regions consumed

flowers of mariposa lilies (Calochortus sp.). In Oregon there are 7 mariposa lilies that are listed

as state endangered, threatened or candidate species (NRCS 2012). Although lilies did not

comprise a large percentage of the diet (0.06-0.5% aggregate dry mass in spring), they occurred

in over 5% of the crops collected during spring. Additionally, there are numerous other state

threatened, endangered and sensitive plants (Astragalus sp., n = 23; Carex sp., n = 28;

Delphinium sp., n = 3; Draba sp., n = 3; Eriogonum sp., n = 4; Lomatium sp., n = 10; Microseris sp., n = 3; Poa sp., n = 3; Ranunculus sp., n = 2; Rubus n = 2; Trifolium sp., n = 4; Vaccinium myrtilloides; Claytonia lanceolata; Galium kamtschaticum) that were common genera consumed by turkeys in this study, although the impact of any possible consumption is unknown.

The majority of seed taxa present in wild turkey diet in Oregon and Washington were not represented in fecal samples. Of the 62 taxa of seed identified in the diet, 22 taxa were recovered in fecal samples. More taxa would likely be recovered if we had processed a larger sample of feces; however, some taxa common in the diet were not found in feces. For example, there were

20 genera of Poaceae seed detected in the diet, totaling 19.0% aggregate dry mass of the fall- 73

winter diet, but the seed of only one Poaceae taxa (Echinochloa sp.) was found intact and viable

in fecal samples. This indicates that most taxa of grasses consumed are likely destroyed in the

digestive process. Other common seeds consumed that comprised over 5% aggregate dry mass or

occurred in more than 5% of diet samples that were not detected in fecal samples include

Pinaceae, Asteraceae, Ranunculaceae, Boraginaceae, and Apiaceae.

Although wild turkeys appear to be primarily a seed predator, viable seed was recovered

for 9 of the 62 seed taxa detected in the diet (14%; Appendix II-V, Table 3.3). Seed dispersal

capabilities do not differ appreciably between individual birds of the same species (Traveset

1998); therefore if turkeys consume the fruits of plants that were found viable in this study, they

will likely successfully disperse that seed, regardless of region. Of the 9 taxa recovered, 5

(Fabaceae, Toxicodendron sp., Symphoricarpos sp., Vaccinium sp. and Echinochloa sp.) were

represented in the diet in all regions thus it is likely those taxa are being dispersed in all regions

even though they were not detected in the fecal samples. Similarly, even though the 4 remaining

taxa (Polygonum sp., Amaranthus sp., Rubus sp. and Chenopodium sp.) were only represented in

the diet in some regions, it is possible that all turkeys would consume them if encountered and

subsequently disperse the seed. For example, blackberry (Rubus sp., 4.5% viable) comprised

22.0% of the summer diet in Southern Oregon but did not occur in fecal samples collected from

this region (KM region, Table 2.12 and 3.3). Because physiology of wild turkeys does not differ

between regions, it is likely that turkeys in Southern Oregon are dispersing viable Rubus sp. seed.

Fecal sampling and crop collection occurred concurrently throughout the fall-winter

season but average dates of collection were separated by over 1 month. Some seeds may mature

earlier in the season, thus there may be taxa being dispersed that were underrepresented or not

detected in this study. The average day of crop collection was November 9th (day 312.8 ± 3.0) compared to the average day of fecal collections, December 22nd (day 256.3 ± 4.4) which may

result in differences in taxa represented in the diet and taxa represented in fecal samples. For

example, in Southern Oregon (KM region) 49% of seeds recovered were snowberry (n = 582 74

seeds) although snowberry comprised less than 0.1% of the fall-winter diet in Southern Oregon suggesting snowberry may be passed at a disproportionately higher rate, over represented in fecal samples or underrepresented in the diet (Appendix II-V, Table 3.3).

Most taxa identified in the diet and fecal samples were identified to family and there are natives and non-native species within those families. Multiple native raspberry, thimbleberry, salmonberry and native blackberry species occur in the Pacific Northwest but Himalayan blackberry (R. armeniancus) is listed as a noxious weed and is prevalent in both states (NWCB

2013, ODA 2013). Rubus seed recovered from fecal samples was 4.5% viable, and contributed to large portions of the diet in some seasons (summer, 22% aggregate dry mass); thus, it is likely turkeys are dispersing Himalayan blackberry as well as native Rubus species. Conversely, numerous seeds of hawthorn (Crataegus sp., n = 294) were recovered from fecal samples, but

none were viable (Table 3.3). Oregon and Washington have native hawthorn species but one

non-native, singleseed hawthorn (C. monogyna), is a growing management concern (ODFW

2006). Hawthorn fruit was the most common flesh fruit consumed in the NR and BM regions,

thus turkeys appear to be solely a predator of hawthorn seed. A next step in understanding the

impacts of wild turkey seed dispersal effectiveness would be to determine species-specific

relationships by performing feeding trials using a variety of native and introduced plants of

management concern.

I did not consider all mechanisms that turkey foraging behavior could impact ecosystem

structure in this thesis. For example, turkey foraging behavior can influence local habitat

conditions that may affect subsequent germination and growth of plants (Moore and Wein 1977,

Rinkes and McCarthy 2007). Controlled experiments designed to test this mechanism would add

to our understanding of turkeys in Pacific Northwest ecosystems. 75

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