LEAD DEPOSITION DUE TO MOURNING DOVE HUNTING AT TWO CONSERVATION AREAS IN PLATTE COUNTY, MISSOURI Name omitted αPark University and βMissouri Department of Conservation Abstract Mourning doves (Zenaida macroura) are abundant and widespread throughout the United States. Long-term declines in several upland game bird populations have caused wildlife managers to increase other hunting opportunities (e.g. mourning doves), especially on public lands near urban population areas. Lead shot toxicity in game birds was first recognized more than a century ago. This study was conducted to summarize data collected by the Missouri Department of Conservation on managed mourning dove hunts on the Platte Falls (PFCA) and Guy B. Park (GBPCA) conservation areas in Platte County, Missouri from 1997 through 2007. Each opening day of dove season, hunters were asked to fill out a card with various personal information, hunting times and success, and ammunition characteristics; they were asked to deposit these cards in drop boxes at designated parking areas. Time afield, harvest rates, and lead deposition rates were estimated using data that was collected. At PFCA, we estimated 309.68 pounds of lead was deposited annually on the 60 acres of managed dove fields each opening day of dove season. At GBPCA, 11.44 pounds of lead was deposited annually on about 8 acres of managed land. This is a minimal estimate; true annual lead deposition rates are probably several times higher due to several factors: data collected only during opening day of dove season, an unknown percentage of hunters do not report hunting activity, other small game hunting takes place on these areas, and reliability of self-reported data from hunters. Lead Deposition Guy B. Park CA Platte Falls CA Acres managed for doves 8 60 Pounds of lead/year 11.44 309.68 Pellets/acre/year* 9381 33859 Pellets/foot2/year* 0.215 0.777 *assumes 410 pellets per 1-ounce load of #8 shot Table 1. Platte Falls Conservation Area Opening Day of Dove Season Statistics Year # Hunters # Doves Harvested Average Time in Field Average Doves/Hunter Average Lead Deposited (lb) 1997 127 1424 N/A 11.21 534.00 1998 328 656 2.00 246.00 1999 241 662 2.75 248.25 2000 132 528 5.28 198.00 2001 165 559 3.39 209.63 2002 39 225 5.76 84.38 2003 171 1159 6.80 434.63 2004 87 712 2.82 8.18 267.00 2005 99 871 2.58 8.80 326.63 2006 224 1701 2.91 7.59 637.88 2007 196 587 2.90 2.99 220.13 164.45 825.82 2.80 5.89 309.68 http://www.dnr.sc.gov/news/Yr2006/april10/Dove.jpg Discussion GBPCA has less acreage managed for hunting and is a smaller, less known conservation area. As active dove management began only in 2004 and there is less room for hunters, less dove hunting is done there. Weather, day of the week, and number of doves locally all play a role in the number of hunters and doves harvested each opening day of dove season. It is unknown what percentage of hunters fill out cards. A notable percentage of hunters do not self-report, therefore the number of hunters, number of doves harvested, and lead deposition rates are probably underestimated. Lead deposition rates were measured using data that was collected. Many of the assumptions are conservative. For PFCA and GBPCA, we estimated 310 and 11 pounds of lead was deposited on and near managed dove fields each year just opening day of dove season. This only represents opening day dove hunters, not other small game hunters that use these two areas throughout the year. http://aliciagoranson.blogspot.com/2006/02/mourning-dove.html Study Areas PFCA—Platte Falls Conservation Area 1 mile east of Platte City, MO 60 acres of managed dove fields GBPCA—Guy B. Park Conservation Area 5 miles north of Platte City, MO 8 acres of managed dove fields Methods Opening day of dove season only Each hunter asked to fill out a information card name number of doves harvested time period they hunted shots fired doves crippled shot size and weight Drop boxes at designated parking lots Data entered into Excel for analysis Lead deposition estimation hunters reported 6 shots per bird harvested assuming 1 ounce of lead per shotshell lead calculated by the following equation: estimated lbs. of lead = (birds harvested * 6 shots)/16 Courtesy of Rio Ammo Management Recommendations Collection of additional data on survey cards Soil sampling of managed dove fields Mandatory check stations? entrance survey exit surveys expensive & labor intensive hunter dissatisfaction with time/effort Mandatory steel (nontoxic) shot? Field management to reduce lead exposure rotation of fields deep disking Table 2. Guy B. Park Conservation Area Opening Day of Dove Season Statistics Year # Hunters # Doves Harvested Average Time in Field Average Doves/Hunter Average Lead Deposited (lb) 2004 6 12 3.25 N/A 4.50 2005 9 28 3.44 3.11 10.50 2006 16 55 2.34 20.63 2007 10 27 3.60 2.70 10.13 10.25 30.5 3.16 3.08 11.44