1092 TRANSMITTER EFFECTS ON MOURNING DOVES

Physiological effects ofradiotransmitters on mourning doves

John H. Schulz, Joshua J. Millspaugh, Brian E. Washburn,AlexJ. Bermudez, James L. Tomlinson, Tony W. Mong,

and Zhuoqiong He

Abstract It is critical to understand how radiotransmitters and their attachment techniquesimpact marked individuals. Many studies of transmitter effects assess only overt, dele-terious effects. However, physiological effects caused by attachment techniques mightcompromise the integrity of resulting information. Our objectives, therefore, were toassess the efficacy of subcutaneous implants and determine the physiological effectson mourning doves (Zenaida macroura) using heterophihlymphocyte (H:L) ratios, andfecal glucocorticoid measures. We conducted 2 trials with 60 mourning doves; 1 insummer-autumn (trial #1) and 1 in autumn-winter (trial #2). For each trial we assigned1 5 male and 15 female doves to either a subcutaneous implant treatment or a controlgroup. During the 2 trials, we observed no differences in body masses, H:L ratios orfecal corticosterone levels between mourning doves with subcutaneous implants andthe control group. Given the ultimate use of the information obtained from telemetryprojects and cost of the resulting initiatives, expenditures associated with rigorousexperimental evaluations can only improve the basis of reliable knowledge used inmaking resource management decisions.

Key words fecal corticosterone, heterophihlymphocyte ratio, Missouri, mourning dove,radiotelemetry, subcutaneous implant, transmitter attachment, Zenaida macroura

Although it has been >40 years since the devel- have a thorough understanding of how transmittersopment of wildlif e radiotelemetry, there continues and their attachment techniques impact theto be uncertainty about the effects of transmitters marked individual and the resulting information,on individually marked birds and its effects on the Attempts to evaluate transmitter effects oftenresulting information. Given this uncertainty, have focused on measuring overt responses such asnumerous methods have been developed for changes in behavior (Hooge 1991, Brook and Clarkattaching radiotransmitters to birds (Kenward 2002, Jones et al. 2002), nest attendance or aban-2001, Naef-Daenzer et al. 2001,Withey et al: 2001). donment (Morris and Burness 1992, Stafford et al.Each transmitter attachment technique, however, is 2002), or differences in growth and body massa compromise between minimizing potential nega- (Ewing et al. 1994, Hubbard et al. 1998). Othertive effects of carrying the transmitter and maxi- transmitter evaluations have examined recapturedmizing transmitter retention. Thus, it is critical to individuals for transmitter or harness-related

Address for John H. Schulz: Missouri Department of Conservation, Resource Science Center, 1110 South College Avenue, Colum-bia, MO 65201, USA; e-mail: John.H.Schulz@mdc.mo.gov. Address for Joshua J. Millspaugh, Brian E. Washburn, and Tony W.Mong: Department of Fisheries and Wildlife Sciences, University of Missouri, 302 Anheuser-Busch Natural Resources Building,Columbia, MO 65211, USA; present address for Washburn: United States Department of Agriculture, Animal and Plant HealthInspection Service, 6100 Columbus Avenue, Sandusky, OH 44870, USA. Address for Alex J. Bermudez: University of Missouri,Veterinary Medicine Diagnostic Laboratory, Columbia, MO 65211, USA. Address for James L. Tomlinson: University of Missouri,Veterinary Medical Teaching Hospital, Columbia, MO 65211, USA. Address for Zhuoqiong He: University of Missouri, StatisticsDepartment, Columbia, MO 65211, USA.

Wildlife Society Bulletin 2003, 33(3):1092-1100 Peer refereed

Transmitter effects on mourning doves • Schulz ct al. 1093

lesions (Olsen et al. 1992, Guillemette et al. 2002),necropsied individuals in experimental laboratorytrials (Korschgen et al. 1996; Schulz et al. 1998,2001), or examined differences in demographiccharacteristics of treatment and control groups(Naef-Daenzer et al. 2001). However, subtle physio-logical effects caused by attachment techniquesalso may compromise the resulting information.For example, the release of stress hormones (e.g.,glucocorticoids) may influence animal behavior(Millspaugh and Washburn 2004). Therefore, evalu-ations of transmitter impacts should considerparameters such as physiological effects of thetransmitter that might not be overtly obvious.

Traditionally, physiological measures of stresshave involved invasive methods that require animalcapture and restraint; e.g., blood collection to mon-itor changes in CO2 production (Gessaman andNagy 1988), heterophil:lymphocyte ratios (Schulzet al. 1998,Vleck et al. 2000), and changes in plasmacorticosterone levels (Roy and Woolf 2001).Capture, restraint, and blood collection can com-promise an accurate assessment of stress (Hamiltonand Weeks 1985, Le Maho et al. 1992), althoughsuch measures are still useful for studies evaluatingadrenal responsiveness to capture. Measurement offecal glucocorticoid metabolite concentrations,however, provides a non-invasive alternative todirect blood collection for avian plasma corticos-terone analysis (Wasser et al. 2000, Ludders et al.2001, Suedkamp Wells et al. 2003). Recently, aradioimmunoassay procedure to quantify fecal glu-cocorticoid metabolites in mourning dove(Zenaida macroura) feces has been developedand validated (Washburn et al. 2003).

This study represents the third of 3 independent,but linked, investigations attempting to build reli-able knowledge (Romesburg 1981, Morrison et al.2001) about the effects of attaching and carryingradiotransmitters using mourning doves as themodel. The first study showed no difference in het-erophil:lymphocyte (H:L) ratios between a controlgroup of mourning doves and a group with subcu-taneous implants with external antennas; however,a group with intra-abdominal implants and externalantennas showed significantly higher H:L ratios at 1week and 10 weeks post-treatment (Schulz et al.1998). The second study showed that subcuta-neous implants were superior to glue attachmentbased on retention time, and superior to harnessesbased on pathological effects (Schulz et al. 2001).Although both studies showed that subcutaneous

implants were a tractable transmitter attachmenttechnique, neither conducted surgical proceduresunder field conditions and the birds had limitedmobility due to experimental constraints of cagesize. Thus, our objectives in this study were to testthe efficacy of conducting subcutaneous implantsurgeries under field conditions and determine thephysiological effects of subcutaneously implantedradiotransmitters on captive wild mourning doveskept in cages allowing limited flight using fecal glu-cocorticoid assays and H:L ratios.

Study area and methodsStudy animals

From July 2000-April 2001, we captured wildmourning doves in central Boone County, Missouri(38° 54' N, 92° 18' W) with modified Kniffin traps(Reeves et al. 1968) baited with white millet and sun-flower seeds. We transported captured doves to theUniversity of Missouri's Baskett Wildlif e Research andEducation Area (BWREA; 38° 45' N, 92° 12'W), fittedthem with individually numbered aluminum legbands, and placed each bird in large outside pens(Mong et al. 2002) with <20 doves per pen. Genderinitially was determined based on external plumagecharacteristics (Schulz et al. 1995) and confirmedlater by internal examination of the gonads at the endof the study. Mourning doves had reached adult pre-basic molt by the start of the experiment and were allconsidered adults. After a >6-week period to accli-mate the doves to captivity, we placed doves individ-ually in 1 of 60 large outside cages (244 x 183 x 183cm; Mong et al. 2002). We fed birds a mixed grain dietconsisting of sorghum grains, wheat, corn, oats, andsunflower seed; we provided food and water ad libi-tum. Although the cages used in our experimentwere considerably larger than those used in eitherSchulz et al. (1998) or Schulz et al. (2001), movementof the birds was still limited. We acknowledge that anexperimental design using cages allowing moreextended flight (e.g.,free-flying wild conditions) mayhave provided different results.

We conducted 2 trials of the experiment with 60mourning doves in each; 1 trial was conducted insummer-autumn (trial #1; July 2001-October2001) and 1 during autumn-winter (trial #2;October 2001-January 2002). For each trial we ran-domly assigned 15 male and 15 female mourningdoves to either receive a subcutaneous implantwith an external antenna or act as a control with noimplant or surgery.

1094 Wf/tfiifr 21 in* H»2-I mo

Blood and fecal samplingWe collected blood and fecal samples to deter-

mine H:L ratios and fecal glucocorticoid metabolitelevels as independent measures of physiologicalstress. We collected blood samples during 8 ses-sions for each of the 2 trials; 6,4, and 2-weeks pre-treatment, 1-2 days prior to application of treat-ments, and 1-2 days post-treatment, 2, 4, and 6weeks post-treatment. We collected fecal samples<8 hrs prior to blood collection. Because fecal sam-ples could be collected without handling thedoves, we collected more fecal than blood samples.For trial #1 we collected fecal samples during 12sessions; 6, 5,4, 3, and 2 weeks, and 1-2 days priorto application of treatments, 1-2 days post-treat-ment, 1,2,3,5, and 6 weeks post-treatment. For trial#2 we collected fecal samples during 14 sessions; 6,5, 4, 3, 2, and 1 •wee k pretreatment, 1-2 days pre-treatment, 1-2 days post-treatment, 1, 2, 3,4, 5, and6 weeks post-treatment.

We also measured body mass during each bleed-ing session using an electronic balance (Model #V-1200, Acculab, Newtown, Penn.). We measuredbody mass during 8 sessions for each of the 2 trials;6, 4, 2 weeks pretreatment, and 1-2 days prior toapplication of treatments, 1-2 days post-treatment,2,4, and 6 weeks post-treatment.

During each bleeding session, we collected <0.3cc of blood from each dove (Clipsham 1991,Jenkins 1997) and made 2 blood smears. After col-lecting blood, we made smears, air-dried them,stained each with Wright-Giemsa stain at the labo-ratory (University of Missouri Veterinary MedicalDiagnostic Laboratory, Columbia, Mo.), and exam-ined them under a light microscope (Schulz et al.1998, 2001). The same person read all slides. Weidentified cells using standard avian guidelines, andon each slide heterophils and lymphocytes werecounted until the cumulative total was 100 cells(Campbell 1988).

Fecal sample preparation and assaysWe collected fresh fecal material (<1 hr old) from

the sides of the pens. We froze fecal samples at-20°C within 10 minutes of collection. We placedfrozen fecal samples into a lyophilizer (Freeze-drySpecialties, Inc. Osseo, Minn.) for 24 hours. Next,we sifted samples through a stainless steel mesh toremove large particles and thoroughly mixed eachsample. We extracted fecal glucocorticoid metabo-lites from feces using a modification ofSchwarzenberger et al. (1991). We placed dried

feces in a test tube with 2.0 mL of 90% methanoland vortexed the sample for 30 minutes. We cen-trifuged samples at 500x g for 20 minutes, saved thesupernatant, and stored at -84°C until assayed. Weused I125 corticosterone radioimmunoassay (RIA)kits (ICN #07-120103, ICN Biomedicals, Costa Mesa,Calif.) previously validated for use in mourningdoves (Washburn et al. 2003) to quantify glucocor-ticoid metabolite concentrations. We analyzed fecalsamples in 10 assays, with each assay including allthe samples from an individual bird. We followedthe ICN protocol for the I125 corticosterone RIA,except that we halved the volume of all reagents.

Surgical proceduresSubcutaneous transmitters were similar to those

used by Schulz et al. (1998) and Schulz et al. (2001).They weighed 3.2-3.6 g with a 15-cm antenna anda 0.53-mm outside diameter and contained a ther-mistor regulating the transmitter pulse rate by tem-perature (Model 386, Advanced Telemetry Systems,Isanti, Minn.).

Surgeries were conducted outdoors under acanopy using an elevated portable table coveredwith disposable absorbent towel (Versi-Dry™,Nalgene Products, Rochester, N.Y.). One of the 2veterinary surgeons conducted the surgical proce-dures during the first trial, and one during the sec-ond trial; an additional person was needed forassisting with anesthesia during each trial. Weplaced doves on an electrical heating pad duringthe winter trial to help doves maintain body tem-perature while anesthetized. After completion ofthe surgery, doves were immediately returned totheir respective cages, and post-operative care con-sisted of observation without any special holding,restraint, or analgesic agents.

We performed necropsies at the end of each 6-week post-treatment period similar to Schulz et al.(1998) and Schulz et al. (2001). We examined tissuesections from all treatment birds for tissue inflam-mation and bacterial infection.

Statistical analysesWe used 3 separate repeated measures of analy-

sis of variance (ANOVA; GLM; SAS Institute 1990)to evaluate differences in post-treatment bodymass changes (e.g., differences in successive sam-pling periods) by treatment and gender, post-treat-ment changes in log-transformed H:L ratios bytreatment and gender, and the reciprocal transfor-mations of fecal glucocorticoid metabolites by

Transmitter effects on mourning doves • Schul/ el al. 1095

treatment and gender. Because we held captivemourning doves in outdoor cages on a rural facili-ty, we experienced several predation episodes dur-ing the summer and winter trials, and some dovesdied during anesthesia-surgery. Thus, some datafrom our doves were censored where repeatedmeasurement analysis was used (11 doves fromtrial #1 and 1 from trial #2); the distribution of age,gender, and treatment of these unrelated mortali-ties did not affect our results. We examined alltests of significance at a = 0.05, and all means arepresented+standard error.

ResultsImplant surgeries

During our 2 trials, we surgically implanted 65subcutaneous radiotransmitters with externalantennas in mourning doves; 34 procedures duringtrial #1 and 31 during trial #2. During trial #1, 4doves died due to anesthetic complications duringor shortly after the surgical process.

Summer post-surgery evaluationsDuring the summer (trial #1), 1 dove expelled its

implanted transmitter between the surgery and the2-day post-treatment evaluation; 29 transmittersremained implanted for the remainder of the trial.During the post-surgery evaluation 2 days afterimplantation, we observed 28 doves with the trans-mitter located in the thoracic inlet and 1 dove withthe transmitter adjacent to the surgical site; loca-tions of transmitters remained the same for theremainder of the trial. Also, during our 2-day post-surgery evaluation, we observed 26 surgical sitesthat were unremarkable; 3 had partially dehisced.After 2 weeks, we observed 28 doves with unre-markable surgical sites; 1 site remained partiallydehisced. During subsequent 4-week and 6-weekevaluations we observed that the partially dehisceddove continually showed secondary healing at thesurgical site. Antenna exit sites were unremarkablefor all doves during the entire summer trial. Whennecropsies were conducted, we observed no com-plications with the transmitters in the thoracicinlet; we observed 26 (90%) doves with unremark-able subcutaneous antenna tracts and 3 (10%) with<2 cm of mild inflammation.

During trial #1 we found no differences betweenpretreatment and post-treatment body masschanges by gender CF6i35 = 1.12, Pillai's trace =0.161, P = 0.373), treatment (F655 = 0.72, Pillai's

trace = 0.110, P = 0.636), or gender x treatment(̂ 6,35 = 0.170, Pillai's trace = 0.226, P = 0.218).Within trial #1, there were differences among datacollection sessions as the captive birds gained massas summer progressed into autumn (/^ 43 = 22.69,Pillai's trace=0.6l3,^<0.0001). There were no sig-nificant interactions with data collection sessions(e.g., session x gender; all P>0.5). Pathologicalexaminations of implanted mourning doves duringnecropsy were unremarkable, and no histopatholo-gy samples were necessary.

Winter post-surgical evaluationsDuring the winter (trial #2), 1 dove expelled its

transmitter between the 2-day and 2-week post-treatment evaluation; 29 transmitters remainedimplanted for the remainder of the trial. During the2-day post-surgery evaluation, we observed 11doves with their transmitter located in the thoracicinlet and 19 with the transmitter located adjacentto the surgical site. During the 2-week post-surgeryevaluation, however, we observed all 29 transmit-ters located in the thoracic inlet; locations of trans-mitters remained the same for the remainder of thewinter trial. We observed that all surgical sites andantenna exit sites were unremarkable during theentire winter trial. During necropsies, we observedno complications with the transmitters in the tho-racic inlet; 26 (90%) doves had unremarkable sub-cutaneous antenna tracts and 3 (10%) with <2 cmof mild inflammation.

During trial #2 we observed differences amongdata collection sessions as all captive birds gainedmass during the post-treatment period (F^ ̂ 2 =108.54, Pillai's trace = 0.862, P<0.0001). We alsoobserved a treatment effect where implanted dovesweighed slightly more than doves in the controlgroup during the post-treatment period (F451 =12.35, Pillai's trace = 0.492,JP<0.0001). There was asignificant session x treatment interaction {F^ 52 =3.64, Pillai's trace = 0.174, P=0.018). We observedno differences in mass change with repeated meas-ure analysis between gender (^4^ = 1.35, Pillai'strace = 0.095, P=0.266), gender x treatment (F4 51 =2.09, Pillai's trace = 0.l4l,P=0.096), session x gen-der (F3 52 = 1.69, Pillai's trace = 0.089, P= 0.181), orsession x gender x treatment (F552=1.21, Pillai'strace = 0.065,P=0.317). Pathological examinationsof implanted mourning doves during necropsywere unremarkable, and no histopathology sampleswere necessary.

1096 soih-n liuiivttn iw*. .WVIO«>2-I 100

Female Female

Figure 1. Heterophihlymphocyte (H:L) ratios (mean + SD) forfemale (A) and male (B) captive mourning doves receiving sub-cutaneously implanted transmitters and a control group duringsummer/fall 2001 (trial #1).

Figure 2. HeterophiHymphocyte (H:L) ratios (mean ± SD) forfemale (A) and male (B) captive mourning doves receiving sub-cutaneously implanted transmitters and a control group duringfall/winter 2001 (trial #2).

H:L ratios and fecal corticosteroneRepeated measurement analysis of the post-treat-

ment changes in H:L ratio showed no differencesbetween or within subject effects during trial #1(all />>0.09). During trial #2, however, we observeddifferences between gender x treatment (F^5Q =2.67, Pillai's trace = 0.176, P=0.043) and session xgender x treatment (F351 = 2.88, Pillai's trace =0.145, -P = O.O45). During trial #1, average femaleH:L ratios for implant doves were higher during the6-week pretreatment period compared with dovesin the control group, and remained higher duringthe post-treatment period (Figure la); average maleH:L ratios during trial #1 showed no pattern (Figure\b). During trial #2, there were no differences (allP>0.10) or patterns in H:L ratio changes forfemales (Figure 2a); however, H:L ratios for maledoves in control and implant groups showed grad-ual increases as winter progressed during trial #2(Figure 2b).

During trial #1, we observed no differences withbetween subject effects in fecal corticosterone lev-els (all P>0.08); however, we observed a differenceamong data collection sessions as the trial pro-gressed (̂ 5 36= 10.89, Pillai's trace = 0.602, P<0.0001) (Figure 3a, b). During trial #2 we observedno differences with between or within subjecteffects in fecal corticosterone levels (all P>0.10)(Figure 4a, b).

DiscussionResults from the last of our 3 investigations

attempting to build reliable knowledge(Romesburg 1981, Morrison et al. 2001) about theeffects of attaching and carrying radiotransmittersindicated that subcutaneous transmitters withexternal antennas are a tractable research fieldtechnique for mourning doves. During 2 inde-pendent trials, 1 in summer and 1 in winter, we

60

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Transmitter effects on mourning doves • Schulz ct al. 1097

/ ^ Female

J, Tl l l

1 2 3 4 5 6 7 8 9 10 11 12

Session

Male

5 6 7 8 9

Session

10 11 12

Figure 3. Fecal glucocorticoid metabolite (FECAL CORTICOS-TERONE) concentrations (mean ± SD) for female (A) and male(B) captive mourning doves receiving subcutaneously implant-ed transmitters and a control group during summer/fall 2001(trial #1).

60

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1 2 3 4 5 6 7 8

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Figure 4. Fecal glucocorticoid metabolite (FECAL CORTICOS-TERONE) concentrations (mean + SD) for female (A) and male(B) captive mourning doves receiving subcutaneously implant-ed transmitters and a control group during fall/winter 2001(trial #2).

observed no differences in body masses, H:L ratios(Figures 1-2), or fecal corticosterone levels (Figures3-4) between mourning doves with subcutaneousimplants and a control group.

This study is unique because we evaluated phys-iological stress related to the implanted transmit-ters using 2 independent measures (i.e., H:L ratiosand fecal corticosterone levels). H:L ratios havebeen successfully used to measure physiologicalstress in previous avian research projects (Schulz etal. 1998,Vleck et al. 2000, Schulz et al. 2001). Fecalcorticosterone, however, provides a noninvasivedata collection tool (Washburn et al. 2003) com-pared to H:L ratios or direct measures of blood cor-ticosterone levels which can compromise an accu-rate assessment of stress (Hamilton and Weeks1985, Le Maho et al. 1992).

Our results indicated that implanting radiotrans-mitters, although a relatively simple surgical proce-

dure, requires considerable experience and prepa-ration compared to attaching harness or glue-ontransmitters. Before other researchers considerusing subcutaneous transmitter implants for anavian field research project, we recommend thatinvestigators conduct >20 procedures under realis-tic field conditions and obtain training from aboard-certified veterinary surgeon and anesthesiol-ogist. Although training and start-up costs associat-ed with using implanted radiotransmitters in fieldsettings may be higher compared to traditionalexternal transmitter attachment, we believe theextra effort and costs are minor compared to theoverall project cost and the ultimate use of theinformation collected from the marked animals.The extra expenditures usually involve one-timeequipment purchases (e.g., a portable anesthesiamachine [~$2,500 U.S.]).

Unlike Schulz et al. (2001) where all 40 subcuta-

1 098 Wildlife Society Bulletin 2005. 33(3): 1092-1100

Radiograph showing the location of the radio transmitter in thethoracic inlet and the subcutaneous transmitter antenna.

neous transmitters remained implanted, weobserved 1 dropped transmitter during each trialrepresenting 3-4% of our entire marked sample.The occurrence of dropped transmitters in thisstudy is likely more representative of what could be

expected in field application of the technique,especially when birds are released directly into thewild immediately after surgery. Although droppedtransmitters represent a loss of valuable informa-tion, other studies using subcutaneous implantshave reported rates as high as 10.6% for scaup(Aythya affinis; Brook and Clark 2002). However,retention rates for subcutaneous implants are sub-stantially greater compared to 38.5% for glueattachment and 74.4% for double-wing loop har-nesses (Schulz et al. 2001). Other avian researchershave reported 100% transmitter loss for glue-ontransmitters at 8-12 days post-attachment (Masseyet al. 1988).

Unlike previous investigations evaluating trans-mitter effects, results from our 3 studies incremen-tally showed the 1) development and physiologicalevaluation of the transmitter attachment techniquewith 200 individuals (Schulz et al. 1998), 2) experi-mental comparison of the new technique to exist-ing traditional methodology using 195 birds (Schulzet al. 2001), and with this study, 3) independentreplication of the experiment in the out-of-doorsusing multiple and independent measures of stresswith 2 different trials during different seasons with120 doves. Independent replication of studies eval-uating transmitter effects is critical if a completeassessment of deleterious impacts on the resultingdemographic estimates or behavioral characteris-tics will be achieved (Guillemette et al. 2002). Webelieve this step-wise thought process provides atemplate for evaluating the impact of transmitterson almost any bird species. The need for this typeof rigorous evaluation is critical when placed in thecontext of endangered species recovery, or speciesmanagement where large-scale habitat activities arederived from data obtained from avian telemetrystudies (e.g., the North American Bird ConservationInitiative, and United States federal farm bill legisla-tion). Although numerous attempts have beenmade to evaluate transmitter effects with varyingdegrees of success, we recommend that researchersassume that any radio attachment technique mayhave an impact, measurable or immeasurable.

Based on our results and experience, we urgecaution and restraint when conductingradiotelemetry studies to obtain estimates of demo-graphic characteristics to be used in further popu-lation or habitat models that, in turn, will be used tosolicit funding for a range of avian managementactivities. Given the ultimate use of the informationobtained from avian telemetry field projects and

Transmitter cffcLts on mourn ing doves • Schulz cl al. 1099

the cost of the resulting initiatives, research timeand costs associated with rigorous testing can onlyimprove the basis of the reliable knowledge(Romesburg 1981) used in avian population andhabitat management.

Acknowledgments. Doves used in experimentswere collected and held under a United States Fishand Wildlif e Service scientific collection permit(MB841083-1) and maintained in accordance withUniversity of Missouri animal care and use proto-cols (Protocol Reference no. 3624). Funding forthis study was provided by 2001 Webless MigratoryGame Bird Research Program (United States Fishand Wildlif e Service and the United States Geologi-cal Survey-Biological Resources Division), MissouriDepartment of Conservation-ConservationResearch Center (Federal Aid in Wildlif e Restora-tion Project W-13-R-56), University of Missouri(Department of Fisheries and Wildlif e Sciences; Vet-erinary Medical Teaching Hospital; Veterinary Diag-nostic Laboratory), and Advanced Telemetry Sys-tems (Isanti, Minnesota). We also thank X. Gao forhelpful comment? on this manuscript.

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John H. Schulz (photo) is resource scientist for the MissouriDepartment of Conservation, and is primarily involved withmourning dove research geared toward improving regional andnational dove harvest management decisions. John received hisB.S. and M.A. in biology from Minnesota State University (for-merly Mankato State University). He is a member of TheWildlife Society (TWS), a past-president of the Missouri TWSChapter, and past-president of the TWS North Central Section.Joshua J. (Josh) Millspaugh is an assistant professor of wildlifeconservation at the University of Missouri (MU). Prior to join-ing the MU faculty, Josh was a postdoctoral researcher in theSchool of Fisheries at the University of Washington (UW). Joshreceived his Ph.D. in wildlife science from the UW, his M.S.from South Dakota State University, and his B.S. from SUNYCollege of Environmental Science and Forestry (SUNY-ESF). Hisresearch focuses on the design and analysis of radiotrackingstudies, large-mammal ecology and management, and therefinement and application of non-invasive hormone assays inwildlife conservation. Brian E. Washburn is a research biologistwith USDA, Wildlife Services, National Wildlife ResearchCenter, Ohio Field Station in Sandusky. Previously, Brian was apostdoctoral Fellow in the Department of Fisheries and WildlifeSciences at MU. He received his B.S. from SUNY-ESF, his M.S.from Pennsylvania State University, and his Ph.D. from theUniversity of Kentucky. His research interests include wildlifenutrition and physiology, restoration of native ecosystems, andforest and grassland habitat management. Alex J. Bermudezreceived his B.S. in biology from Bates College in Lewiston,Maine, M.S. in veterinary medical science from the Universityof Illinois, and a Doctorate of Veterinary Medicine from theUniversity of Illinois. He is a board-certified poultry veterinari-an, an associate professor of veterinary pathobiology at theUniversity of Missouri-Columbia, and serves as the avianpathologist at the Veterinary Medical Diagnostic Laboratory.James L. (Jim) Tomlinson received a B.S. and D.V.M. from the

University of Minnesota and a Masters of Veterinary Sciencefrom the University of Saskatchewan. Jim is a diplomate of theAmerican College of Veterinary Surgeons and is currently a fullprofessor of surgery at the University of Missouri-Columbia'sCollege of Veterinary Medicine. Tony W. Mong received a B.S.in wildlife and fisheries from the University of Missouri-Columbia, and an M.S. from Kansas State University. Currently,Tony is a research specialist for the University of Missouri'sDepartment of Fisheries and Wildlife, working on a long-termmourning dove field project using subcutaneously implantedtransmitters. Zhuoqiong He received her B.S. in mathematicsand an M.S. in applied mathematics from the Hunan University,China, and an M.S. in applied statistics and a Ph.D. in statisticsfrom Purdue University. She worked as a wildlife biometricianfor the Missouri Department of Conservation for 6 years, and iscurrently an associate professor of statistics in the Departmentof Statistics, University of Missouri-Columbia.

Associate editor: Applegate